Polyphenylene sulfide film, polyphenylene sulfide film roll, metallized film composed of same, current collector foil, electrode plate, and secondary battery

A polyphenylene sulfide film with controlled elongation rates and crystallinity addresses in-plane uniformity issues, improving processability and adhesion, reducing wrinkles and cracks during metal layer formation.

WO2025142679A1PCT designated stage expired Publication Date: 2025-07-03TORAY INDUSTRIES INC
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Patent Information

Application Number
PCT/JP2024/044761
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2023-12-25
Filing Date
2024-12-18
Publication Date
2025-07-03

AI Technical Summary

Technical Problem

Existing polyphenylene sulfide films exhibit issues with in-plane uniformity of dimensional changes and handleability during processing steps such as metal layer formation and electrode formation, leading to wrinkles and cracks.

Method used

A polyphenylene sulfide film with specific elongation rates, crystallinity, and dielectric properties, along with controlled elongation rates and elastic moduli, is developed to enhance processability and uniformity, ensuring minimal dimensional changes and improved adhesion with metal layers.

Benefits of technology

The film exhibits improved processability by reducing wrinkles and cracks during metal layer formation, maintaining excellent adhesion and uniformity, and enhancing the stability of electrode material layers.

✦ Generated by Eureka AI based on patent content.

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Patent Text Reader

Abstract

Disclosed is a polyphenylene sulfide film wherein the elongation rate in the width direction at 230°C is 0.0% or more and 13.0% or less as measured by thermomechanical analysis, and the difference between the maximum value and the minimum value among the elongation rates in the longitudinal direction, the 45° direction, the width direction and the 135° direction at 150°C is 1.6% or less. Also disclosed is a film roll which is obtained by winding a polyphenylene sulfide film which has a width of 700 mm or more. Also disclosed are: a metallized film and current collector foil, each of which is obtained by providing a metal layer on at least one surface of the polyphenylene sulfide film; an electrode plate which is obtained by forming an electrode material layer on the surface of the current collector foil; and a secondary battery which uses the electrode plate. The present invention provides a polyphenylene sulfide film which has excellent processability.
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Description

Polyphenylene sulfide film, polyphenylene sulfide film roll, and metallized film, current collecting foil, electrode plate, and secondary battery made thereof

[0001] The present invention relates to a polyphenylene sulfide film, a polyphenylene sulfide film roll, and a metallized film, a current collecting foil, an electrode plate, and a secondary battery made thereof.

[0002] Polyphenylene sulfide films have excellent heat resistance, hydrolysis resistance, flame retardancy, chemical resistance, electrical insulation, and other characteristics, and are particularly suitable for use in electrical and electronic equipment, machine parts, and automobile parts.

[0003] Taking advantage of its heat resistance and chemical resistance, polyphenylene sulfide films have been used as dielectrics in film capacitors, and in recent years, they have been increasingly used as battery components, such as current collector foils for lithium-ion batteries. To be suitable for these applications, they must have excellent processability as a substrate to prevent problems such as wrinkles and cracks during processing steps such as metal layer formation and electrode formation. Examples of polyphenylene sulfide films with excellent processability include a polyphenylene sulfide film that is resistant to breakage and perforation (Patent Document 1), a polyphenylene sulfide film with excellent adhesiveness (Patent Documents 2 and 3), and a polyphenylene sulfide film with excellent dimensional stability (Patent Document 4).

[0004] International Publication No. 2022 / 004414 JP 2019-89317 A JP 2016-69445 A JP 2008-202127 A

[0005] However, while polyphenylene sulfide film has a fairly good processability, there is room for improvement in the in-plane uniformity of dimensional change, and there is also room for improvement in the handleability as a product that requires processing such as metal layer formation and electrode formation.

[0006] An object of the present invention is to provide a polyphenylene sulfide film that is excellent in processability.

[0007] To solve the above problems, the present invention has the following configurations. [1] A polyphenylene sulfide film containing a polyphenylene sulfide resin as a main component, wherein the polyphenylene sulfide film has a width direction elongation of 0.0% to 13.0% at 230°C as measured by thermomechanical analysis (TMA), and the difference between the maximum and minimum elongations in the longitudinal direction, 45° direction, width direction, and 135° direction at 150°C as measured by TMA is 1.6% or less. [2] The polyphenylene sulfide film according to [1], wherein the change in width direction elongation measured by TMA is 0.0% to 8.0% in the range from 150°C to 230°C. [3] The polyphenylene sulfide film according to [1] or [2], wherein the elongations in the longitudinal direction, 45° direction, width direction, and 135° direction at 230°C as measured by TMA on a film sample cut into 50 mm x 50 mm pieces in the longitudinal and width directions are all 0.0% to 9.0%. [4] The polyphenylene sulfide film according to any one of [1] to [3], having a crystallinity of 29% or more and 40% or less as determined from the enthalpy of heat of fusion measured using a differential scanning calorimeter (DSC). [5] The polyphenylene sulfide film according to any one of [1] to [4], wherein, when the film is subjected to a tensile test at room temperature of 23°C, the stress F2 at an elongation of 2% and the stress F5 at an elongation of 5% satisfy the following formula in the longitudinal direction: 36.0 [MPa] < F5 - F2 ≦ 54.0 [MPa]. [6] The dielectric constant ε' in the longitudinal direction measured using a molecular orientation meter MD [7] The polyphenylene sulfide film according to any one of [1] to [5], wherein the storage modulus E' at 90°C in the longitudinal direction is measured using a dynamic mechanical analyzer (DMA) under the conditions of a measurement temperature of 25°C to 200°C, a heating rate of 2°C / min, a frequency of 1 Hz, and a displacement of 10 μm. MD90 [GPa] and longitudinal storage modulus E' at 100 ° C. MD100 The polyphenylene sulfide film according to any one of [1] to [6], wherein the ratio of [GPa] satisfies the following relationship: 0.93≦E′ MD100 / E' MD90≦0.98 [8] The polyphenylene sulfide film according to any one of [1] to [7], having a crystallization temperature Tcc of 136°C or higher and 155°C or lower as measured using a differential scanning calorimeter (DSC). [9] The polyphenylene sulfide film according to any one of [1] to [8], having a content of the polyphenylene sulfide resin of more than 98% by mass and 100% by mass or lower, based on the mass of all components constituting the polyphenylene sulfide film.

[10] The polyphenylene sulfide film according to any one of [1] to [9], having a melt flow rate of 40 g / 10 min or higher and 100 g / 10 min or lower, measured under conditions of a temperature of 315.6°C and a load of 5000 g.

[11] The polyphenylene sulfide film according to any one of [1] to

[10] , having a thickness of 1 μm or higher and 30 μm or lower.

[12] A metallized film obtained by providing a metal layer on at least one surface of the polyphenylene sulfide film according to any one of [1] to

[11] .

[13] A current collector foil obtained by providing a metal layer on at least one surface of the polyphenylene sulfide film according to any one of [1] to

[11] .

[14] An electrode plate obtained by forming an electrode material layer on the surface of the current collector foil according to

[13] .

[15] A secondary battery using the electrode plate according to

[14] .

[16] A polyphenylene sulfide film roll having a width of 700 mm or more, which is made by winding a film containing polyphenylene sulfide as a main component, wherein a film sample cut into 50 mm x 50 mm pieces in the longitudinal and width directions of the film roll is measured by thermomechanical analysis (TMA) at Point A, which is 50 mm from one end toward the center, and at Point B, which is 50 mm from the other end toward the center, and the width direction elongation at 230°C is 0.0% to 13.0%, and the difference between the maximum and minimum elongation in the longitudinal, 45°, width, and 135° directions at 150°C measured by TMA is 1.6% or less.

[17] The polyphenylene sulfide film roll according to

[16] , wherein the difference between the elongation in the 45° direction at 230°C at Point A and Point B, which are measured by TMA, is 1.2% or less, and the difference in the elongation in the 135° direction at 230°C is 1.2% or less.

[18] The polyphenylene sulfide film roll according to

[16] or

[17] , wherein the change in widthwise elongation measured by TMA at points A and B in the range of 150°C to 230°C is 0.0% or more and 8.0% or less.

[19] The polyphenylene sulfide film roll according to any one of

[16] to

[18] , wherein the difference between the maximum and minimum longitudinal tensile modulus in the film width direction, measured by the following measurement method, over a 700 mm width centered at the center of the film width direction is 5 MPa or more and 60 MPa or less. (Measurement Method) A polyphenylene sulfide film roll is cut out at 100 mm intervals over the 700 mm width centered at the center of the film width direction, and the longitudinal tensile modulus is measured at eight locations in the width direction with a test length of 100 mm and a pulling speed of 200 mm / min, and the difference between the maximum and minimum longitudinal tensile modulus in the width direction is determined.

[20] The polyphenylene sulfide film roll according to any one of

[16] to

[19] , having a film thickness of 1 μm or more and 30 μm or less.

[21] A metallized film roll obtained by providing a metal layer on at least one surface of the polyphenylene sulfide film roll according to any one of

[16] to

[20] .

[22] A current collecting foil roll obtained by laminating a metal layer on at least one surface of the polyphenylene sulfide film roll according to any one of

[16] to

[20] .

[23] An electrode plate roll obtained by forming an electrode material layer on the surface of the current collecting foil roll according to

[22] .

[24] A polyphenylene sulfide film roll having a width of 700 mm or more, which is made by winding up a film containing polyphenylene sulfide as a main component, wherein samples of 50 mm x 50 mm cut out in the longitudinal and width directions of the film roll at point A, which is 50 mm from one end toward the center, and point B, which is 50 mm from the other end toward the center, are measured by thermomechanical analysis (TMA) and the elongation in the width direction at 230°C is 0.0% or more and 13.0% or less, and the difference in the elongation in the 45° direction at 230°C at point A and point B is 1.2% or less, and the difference in the elongation in the 135° direction at 230°C, as measured by TMA, is 1.2% or less.

[0008] According to the present invention, a polyphenylene sulfide film having excellent processability can be provided.

[0009] The polyphenylene sulfide of the present invention refers to a polymer in which 95 mol % or more of the repeating units are composed of structural units represented by the structural formula of Chemical Formula 1 below. When the ratio of such components is 95 mol % or more, preferably 97 mol % or more, it is possible to suppress a decrease in the crystallinity, softening point, etc. of the polymer and to maintain heat resistance, dimensional stability, mechanical properties, electrical insulation, etc. The polyphenylene sulfide of the present invention may be copolymerized with metaphenylene sulfide units, biphenylene sulfide units, biphenylene ether sulfide units, biphenylene sulfone sulfide units, biphenylene carbonyl sulfide units, naphthalene sulfide units, etc., represented by the structural formula of Chemical Formula 2 below, in an amount not exceeding 5 mol %.

[0010]

[0011]

[0012] The polyphenylene sulfide may contain a copolymerizable sulfide bond-containing unit as a repeating unit as long as it does not adversely affect the elongation of the film of the present invention. The copolymerization method of the polymer may be random or block type.

[0013] In the polyphenylene sulfide film of the present invention, when the mass of all components constituting the polyphenylene sulfide film is taken as 100 mass%, it is preferable that more than 98 mass% but not more than 100 mass% is polyphenylene sulfide resin. When the entire polyphenylene sulfide film is taken as 100 mass%, the content of a resin composition other than polyphenylene sulfide (resin composition (A)) is preferably less than 2 mass%, more preferably less than 1 mass%, and even more preferably substantially absent. By keeping the content of resin composition (A) less than 2 mass%, it is possible to prevent the resin composition (A) from acting on and modifying polyphenylene sulfide during resin melting in an extruder in the film-forming process, thereby preventing the generation of foreign matter in the film and impairing quality.

[0014] The film of the present invention contains polyphenylene sulfide as a main component. Here, when all components constituting the film are taken as 100 mass %, the film is considered to be a "film containing polyphenylene sulfide as a main component" when the film contains more than 50 mass % but not more than 100 mass % of polyphenylene sulfide.

[0015] The polyphenylene sulfide resin constituting the polyphenylene sulfide film of the present invention preferably has a melt flow rate of 40 g / 10 min to 100 g / 10 min, more preferably 50 g / 10 min to 80 g / 10 min, measured at a temperature of 315.6°C and a load of 5,000 g. If the melt flow rate is less than 40 g / 10 min, the viscosity may be too high and melt extrusion or biaxial stretching may be impossible, while if it exceeds 100 g / 10 min, film tearing may occur during longitudinal and transverse stretching or re-stretching.

[0016] The polyphenylene sulfide film of the present invention preferably contains particles to enhance the lubricity of the film. The type of particles that can be used is any particle that does not adversely affect the elongation of the film of the present invention. One type of particle may be used alone, or two or more types may be used in combination. Among the particles, calcium carbonate particles are preferred because of their good dispersibility in the polyphenylene sulfide film.

[0017] The average particle size of the particles is preferably 0.1 μm or more and 10 μm or less. By setting the average particle size to 10 μm or less, more preferably 5 μm or less, and even more preferably 2 μm or less, the film surface protrusions are prevented from becoming large, and the film can be suitably used without impairing the properties of the metal layer when it is formed. By setting the average particle size to 0.1 μm or more, it is possible to prevent the slipperiness of the film surface from being deteriorated, which can cause scratches during film transport or processing, thereby deteriorating the quality of the film.

[0018] The average particle diameter of the particles refers to the number average particle diameter D obtained by exposing particles by removing polyphenylene sulfide from a polyphenylene sulfide film using a plasma low-temperature ashing method (PR-503 model, manufactured by Yamato Scientific), observing the particles with a transmission electron microscope (TEM H7100, manufactured by Hitachi, Ltd.), connecting the particle images (shades of light caused by the particles) to an image analyzer (QTM900, manufactured by Cambridge Instruments), and performing the following numerical processing on 5,000 or more particles at different observation points: D=ΣDi / N (Di: equivalent circle diameter of particle, N: number of particles).

[0019] The particle content is preferably 0.1% by mass or more and less than 2.0% by mass, more preferably 0.2% by mass or more and 1.8% by mass or less, and even more preferably 0.3% by mass or more and 1.5% by mass or less. By setting the content to less than 2.0% by mass, the film surface protrusions are reduced, and the film can be used preferably without impairing the properties of the metal layer when formed. By setting the content to 0.1% by mass or more, it is possible to prevent the slipperiness of the film surface from being deteriorated, which can cause scratches during film transport or processing, thereby deteriorating the quality of the film.

[0020] The polyphenylene sulfide film of the present invention may be a single layer or a composite film. Examples of composite films include laminate films of two or more layers. For example, it may be a two-layer laminate film consisting of layer A / layer B, or a three-layer laminate film consisting of layer A / layer B / layer A or layer A / layer B / layer C, as long as the laminate film as a whole has the characteristics of the polyphenylene sulfide film of the present invention.

[0021] In a preferred embodiment of the polyphenylene sulfide film of the present invention, the elongation in the width direction at 230°C, as measured by thermomechanical analysis (TMA), is 0.0% to 13.0%, more preferably 0.0% to 9.0%, and even more preferably 0.0% to 5.0%. By setting the elongation in the width direction to 13.0% or less, it is possible to prevent the film from elongating in the width direction due to the thermal load during metal layer formation, thereby preventing wrinkles and improving processability. Furthermore, by setting the elongation in the width direction to 0.0% or more, it is possible to prevent the film from shrinking in the width direction due to the thermal load during metal layer formation, thereby preventing cracks from occurring in the metal layer, thereby improving processability. In particular, by setting the elongation at 230°C within the above range, it is possible to prevent wrinkles from occurring in the film and further prevent wrinkles and cracks from occurring in the metal layer when the film is exposed to high temperatures and tension is applied in the flow direction, such as when a metal layer is formed on a thick film by a single roll-to-roll vapor deposition. Furthermore, by suppressing the occurrence of wrinkles and cracks in the metal layer, it is possible to reduce unevenness in the thickness of the electrode material layer that is applied and formed thereon.

[0022] Methods for adjusting the elongation percentage in the width direction to 0.0% or more and 13.0% or less include a method of adjusting the temperature and magnification at which the film is stretched in the width direction (transverse direction) during the film-forming process, and a method of adjusting the temperature and relaxation rate at which the film is relaxed in the width direction (transverse direction) after being heat-treated after being stretched in the width direction (transverse direction). Note that if the thickness is small, the orientation is more likely to relax during the production process, and the elongation percentage in the width direction tends to be higher.

[0023] In a preferred embodiment of the polyphenylene sulfide film of the present invention, the difference between the maximum and minimum elongation percentages in the longitudinal direction, 45° direction, width direction, and 135° direction at 150°C measured by TMA is 1.6% or less. This difference is more preferably 1.2% or less, and even more preferably 0.7% or less. When the difference between the maximum and minimum elongation percentages is 1.6% or less, the in-plane uniformity of the dimensional change of the film is improved, and when an electrode material layer is formed on the surface of the polyphenylene sulfide film having a metal layer formed thereon, the film elongates uniformly in-plane during drying after application of the electrode material layer, thereby improving the thickness uniformity of the electrode material layer and improving processability.

[0024] A method for making the difference between the maximum and minimum values ​​of the elongation percentage 1.6% or less includes a method in which a film stretched in the longitudinal direction (machine direction) and width direction (transverse direction) in the film-forming process is heat-treated to relax it in the width direction (transverse direction), and then the temperature and magnification at which it is stretched again in the width direction (transverse direction) are adjusted.

[0025] The polyphenylene sulfide film of the present invention preferably has a widthwise elongation change of 0.0% or more and 8.0% or less, more preferably 0.0% or more and 3.5% or less, measured by TMA in the range of 150°C to 230°C. By keeping the widthwise elongation change of 8.0% or less, it is possible to further suppress the film from elongating in the width direction due to the thermal load during metal layer formation, which would otherwise cause wrinkles. Furthermore, by keeping the widthwise elongation change of 0.0% or more, it is possible to further suppress the film from shrinking in the width direction due to the thermal load during metal layer formation, which would otherwise cause cracks in the metal layer, thereby improving processability.

[0026] The polyphenylene sulfide film of the present invention preferably has an elongation of 0.0% or more and 9.0% or less in the longitudinal direction, 45° direction, width direction, and 135° direction at 230°C, as measured by TMA on a film sample cut into 50 mm x 50 mm pieces in the longitudinal and width directions of the film. More preferably, the elongation is 0.0% or more and 5.0% or less. By setting the elongation in each direction to 9.0% or less, the film can be uniformly stretched in-plane due to the thermal load during metal layer formation, thereby further suppressing the occurrence of wrinkles. Furthermore, by setting the elongation in the width direction to 0.0% or more, the film can be further suppressed from shrinking due to the thermal load during metal layer formation, thereby suppressing the occurrence of cracks in the metal layer, thereby improving processability.

[0027] The polyphenylene sulfide film of the present invention preferably has a crystallinity of 29% to 40%, more preferably 30% to 38%, as determined from the enthalpy of heat of fusion measured using a differential scanning calorimeter (DSC). If the crystallinity is less than 29%, the thermal dimensional stability decreases, and wrinkles may occur under the heat load during metal layer formation, resulting in poor processability. If the crystallinity is more than 40%, the adhesion between the polyphenylene sulfide film and the metal layer decreases during metal layer formation, resulting in wrinkles and poor processability.

[0028] In the polyphenylene sulfide film of the present invention, when the film is subjected to a tensile test at room temperature of 23°C, the stress F2 at an elongation of 2% and the stress F5 at an elongation of 5% preferably satisfy the following formula in the longitudinal direction: 36.0 [MPa]<F5-F2≦54.0 [MPa].

[0029] It is more preferable that the following formula be satisfied: 37.5 [MPa]≦F5−F2≦45.0 [MPa]

[0030] By setting the value of (F5-F2) in the range of more than 36.0 MPa and not more than 54.0 MPa, excellent dimensional stability is exhibited against the tensile stress during winding, and even when winding at high speed and high tension, there is less winding slippage, making it possible to produce a more stable wound body.

[0031] Methods for adjusting the value of (F5-F2) to the range of more than 36.0 MPa and not more than 54.0 MPa include adjusting the temperature and magnification at which the film is stretched in the longitudinal direction (longitudinal direction) during the film-forming process, and avoiding high-temperature, long-term heat treatment such as annealing.

[0032] The polyphenylene sulfide film of the present invention has a longitudinal F2 of preferably 65 MPa or more and 75 MPa or less, more preferably 68 MPa or more and 73 MPa or less, and a longitudinal F5 of preferably 104 MPa or more and 120 MPa or less, more preferably 108 MPa or more and 115 MPa or less.

[0033] The polyphenylene sulfide film of the present invention has a longitudinal dielectric constant ε' measured using a molecular orientation meter. MDis preferably 3.00 or more and 3.30 or less, and more preferably 3.10 or more and 3.25 or less. MD By setting the MOR_c value to 3.00 or more and 3.30 or less, the orientation in the longitudinal direction is strong, exhibiting excellent dimensional stability against tensile stress during winding, and winding slippage is reduced even during high-speed, high-tension winding, making it possible to produce a more stable wound body. Furthermore, the MOR_c (Corrected Molecular Orientation Ratio) is preferably 1.00 or more and 1.30 or less, and more preferably 1.00 or more and 1.10 or less. MOR_c represents the ratio of the degree of orientation between the main orientation axis and the axis perpendicular to it, and in principle, 1.00 is the lower limit. In order to uniformly compare the ratio of the degree of orientation between the main orientation axis and the axis perpendicular to it in terms of a thickness of 4 μm, excluding the influence of thickness, MOR_c values ​​corrected for differences due to thickness are used. If MOR_c exceeds 1.30, the in-plane uniformity of orientation decreases, and therefore the in-plane uniformity of dimensional change also decreases. As a result, when an electrode material layer is formed on the surface of a polyphenylene sulfide film on which a metal layer has been formed, the film does not stretch uniformly in-plane when drying after application of the electrode material layer, and the thickness uniformity of the electrode material layer may deteriorate.

[0034] The polyphenylene sulfide film of the present invention has a storage modulus E' at 90°C in the longitudinal direction measured using a dynamic viscoelasticity measuring device (DMA) under the conditions of a measurement temperature of 25°C to 200°C, a temperature rise rate of 2°C / min, a frequency of 1 Hz, and a displacement of 10 µm. MD90 [GPa] and longitudinal storage modulus E' at 100 ° C. MD100 It is preferable that the storage modulus ratio [GPa] satisfies the following relationship: 0.93≦E′ MD100 / E' MD90 ≦0.98

[0035] It is more preferable that the following formula be satisfied: 0.95≦E′ MD100 / E' MD90 ≦0.97

[0036] E' MD100 / E' MD90 By setting the value of E' to 0.93 or more and 0.98 or less, dimensional change is small even if the pressure of the roll press is increased when forming the rolled electrode, and peeling between the metal layer and the film and the occurrence of wrinkles can be further suppressed.MD100 / E' MD90 Examples of a method for setting the value of 0.93 to 0.98 include a method in which a film stretched in the longitudinal direction (machine direction) and width direction (transverse direction) in the film-forming process is heat-treated to relax it in the width direction (transverse direction), and then the temperature and magnification at which it is stretched again in the width direction (transverse direction) are adjusted, and a method in which high-temperature, long-term heat treatment such as annealing treatment is avoided.

[0037] The polyphenylene sulfide film of the present invention has a storage modulus E' at 100°C in the longitudinal direction measured using a DMA under the conditions of a measurement temperature of 25°C to 200°C, a temperature rise rate of 2°C / min, a frequency of 1 Hz, and a displacement of 10 µm. MD100 is preferably 5.30 GPa or more and 7.00 GPa or less, and more preferably 5.50 GPa or more and 6.50 GPa or less.

[0038] The polyphenylene sulfide film of the present invention preferably has a crystallization temperature Tcc measured using DSC of 136°C or higher and 155°C or lower, more preferably 138°C or higher and 150°C or lower. If the crystallization temperature Tcc is lower than 136°C, the effect of re-stretching is insufficient, and the in-plane uniformity of dimensional change is reduced. When an electrode material layer is formed on the surface of a polyphenylene sulfide film having a metal layer formed thereon, the film may not stretch uniformly in-plane during drying after application of the electrode material layer, resulting in poor thickness uniformity of the electrode material layer. If the crystallization temperature Tcc exceeds 155°C, crystallization during heat treatment is insufficient, resulting in poor thermal dimensional stability, and wrinkles may occur due to the heat load during metal layer formation, resulting in poor processability.

[0039] The polyphenylene sulfide film of the present invention preferably has a thickness of 1 μm or more and 30 μm or less. By setting the thickness to 1 μm or more, more preferably 2 μm or more, it is possible to suppress deterioration of productivity due to film breakage during the film formation process and improve handling during the processing step. There is no particular upper limit on the thickness in terms of processability, but when used as a dielectric or a substrate for a current collecting foil in a film capacitor, a thickness of 15 μm or less is more preferable from the viewpoint of miniaturization and thinning.

[0040] A preferred embodiment of the present invention is a polyphenylene sulfide film roll having a width of 700 mm or more, which is obtained by winding up a film containing polyphenylene sulfide as a main component, wherein film samples of 50 mm x 50 mm are cut out in the longitudinal and width directions of the film roll at Point A, which is located 50 mm from one end toward the center, and Point B, which is located 50 mm from the other end toward the center, and the film samples are measured by thermomechanical analysis (TMA) at 230°C. The elongation in the width direction is 0.0% or more and 13.0% or less; and the differences between the maximum and minimum elongations in the longitudinal direction, 45° direction, width direction, and 135° direction at 150°C measured by TMA at Point A and Point B are all 1.6% or less.

[0041] A preferred embodiment of the polyphenylene sulfide film roll of the present invention has a width of 700 mm or more, more preferably 900 mm or more, and even more preferably 1200 mm or more. If the width of the polyphenylene sulfide film roll is less than 700 mm, the processing area per unit speed when forming a metal layer may be small, resulting in poor production costs. The upper limit of the width of the polyphenylene sulfide film roll is not particularly limited, but is generally 2000 mm or less from the viewpoint of handling.

[0042] The length of the polyphenylene sulfide film roll of the present invention is not particularly limited, but is generally 2,000 m or more and 20,000 m or less.

[0043] The polyphenylene sulfide film roll of the present invention has a widthwise elongation at 230°C of 0.0% to 13.0%, more preferably 0.0% to 9.0%, and even more preferably 0.0% to 5.0%, measured by thermomechanical analysis (TMA) on a 50 mm x 50 mm sample cut from one end of the film roll at point A, 50 mm from the center of the film roll, and at point B, 50 mm from the other end of the film, respectively. A widthwise elongation of 13.0% or less can further suppress the occurrence of wrinkling due to the thermal load during metal layer formation, thereby improving processability. Furthermore, a widthwise elongation of 0.0% or more can further suppress the occurrence of cracks in the metal layer due to the thermal load during metal layer formation, thereby improving processability. In particular, by setting the elongation at 230°C within the above range, when the film is exposed to high temperatures and tension is applied in the flow direction, such as when a metal layer is formed on a thick film by a single roll-to-roll vapor deposition, the occurrence of wrinkles in the film and the occurrence of wrinkles and cracks in the metal layer can be further suppressed, improving processability. Furthermore, by suppressing the occurrence of wrinkles and cracks in the metal layer, it is possible to reduce unevenness in the thickness of the electrode material layer formed by coating thereon.

[0044] Methods for adjusting the elongation rate in the width direction to 0.0% or more and 13.0% or less include adjusting the temperature and magnification at which the film is stretched in the width direction (lateral direction) during the film-forming process, and adjusting the temperature and relaxation rate at which the film is relaxed in the width direction (lateral direction) after being heat-treated after being stretched in the width direction (lateral direction).

[0045] In the polyphenylene sulfide film roll of the present invention, the difference between the maximum and minimum elongations in the longitudinal direction, 45° direction, width direction, and 135° direction at 150°C measured by TMA at each of points A and B is preferably 1.6% or less, more preferably 1.2% or less, and even more preferably 0.7% or less. When the difference between the maximum and minimum elongations is 1.6% or less, the in-plane uniformity of the dimensional change of the film is improved, and when an electrode material layer is formed on the surface of the polyphenylene sulfide film having a metal layer formed thereon, the film elongates uniformly in-plane during drying after application of the electrode material layer, thereby further improving the thickness uniformity of the electrode material layer.

[0046] A method for making the difference between the maximum and minimum values ​​of the elongation percentage 1.6% or less includes a method in which a film stretched in the longitudinal direction (machine direction) and width direction (transverse direction) in the film-forming process is heat-treated to relax it in the width direction (transverse direction), and then the temperature and magnification at which the film is stretched again in the width direction (transverse direction) are adjusted. A and the difference R between the maximum and minimum values ​​of the elongation rates in the longitudinal direction, 45° direction, width direction, and 135° direction at 150°C measured by TMA at point B. B Absolute value of the difference |R A -R B is preferably 1.5% or less, more preferably 1.0% or less.

[0047] In the polyphenylene sulfide film roll of the present invention, the difference in elongation in the 45° direction at 230° C. between Point A and Point B is preferably 1.2% or less, and the difference in elongation in the 135° direction at 230° C. is preferably 1.2% or less, more preferably 0.5% or less, and the difference in elongation in the 135° direction at 230° C. is 0.5% or less, and even more preferably 0.3% or less, and the difference in elongation in the 45° direction at 230° C. is 0.3% or less. When the difference in elongation is 1.2% or less, the in-plane uniformity of the dimensional change of the film is further improved, and one end and the other end of the polyphenylene sulfide film roll are elongated to the same extent due to the heat load during metal layer formation, thereby further suppressing the occurrence of meandering during roll-to-roll metal layer formation and improving processability.

[0048] A method for keeping the difference in elongation percentage at 1.2% or less includes a method in which a film stretched in the longitudinal direction (longitudinal direction) and width direction (transverse direction) during the film-forming process is heat-treated to relax it in the width direction (transverse direction), and then the temperature and magnification at which it is stretched again in the width direction (transverse direction) are adjusted.

[0049] The polyphenylene sulfide film roll of the present invention preferably has a widthwise elongation change of 0.0% to 8.0%, more preferably 0.0% to 3.5%, in the range of 150°C to 230°C, as measured by TMA at points A and B. By keeping the widthwise elongation change at 8.0% or less, it is possible to further suppress the film from elongating in the width direction due to the thermal load during metal layer formation, which would otherwise cause wrinkles. Furthermore, by keeping the widthwise elongation change at 0.0% or more, it is possible to further suppress the film from shrinking in the width direction due to the thermal load during metal layer formation, which would otherwise cause cracks in the metal layer, thereby improving processability.

[0050] In the polyphenylene sulfide film roll of the present invention, the difference between the maximum and minimum longitudinal tensile modulus in the film width direction is preferably 5 MPa or more and 60 MPa or less, more preferably 5 MPa or more and 30 MPa or less, over a 700 mm width centered at the center portion in the film width direction.

[0051] (Measurement method) A sample is cut out at 100 mm intervals over a 700 mm width centered at the center of the film width direction to a size of 230 mm in length and 10 mm in width, and the longitudinal tensile modulus is measured at eight locations in the width direction with a test length of 100 mm and a pulling speed of 200 mm / min, and the difference between the maximum and minimum longitudinal tensile modulus in the width direction is determined.

[0052] By setting the difference between the maximum and minimum longitudinal tensile modulus in the film width direction to 5 MPa or more and 60 MPa or less, the polyphenylene sulfide film roll stretches evenly in the width direction due to the tension during metal layer formation, which makes it possible to further suppress the occurrence of meandering during roll-to-roll formation of the metal layer, thereby improving processability.

[0053] (Film Manufacturing Method) The polyphenylene sulfide film and polyphenylene sulfide film roll of the present invention are preferably manufactured, for example, by the following steps.

[0054] First, a method for producing the polyphenylene sulfide will be described. Polyphenylene sulfide can be produced, for example, by polymerizing an alkali metal sulfide (alkali sulfide) and a dihalobenzene.

[0055] Examples of the alkali metal sulfide include lithium sulfide, sodium sulfide, potassium sulfide, rubidium sulfide, and cesium sulfide, with sodium sulfide being preferred. The alkali metal sulfide can be used as a hydrate, an aqueous mixture, or an anhydrous form. It is also possible to use alkali metal sulfides prepared in situ in the reaction system, and alkali metal sulfides prepared from an alkali metal hydrate such as sulfide, lithium hydroxide, or sodium hydroxide and hydrogen sulfide. The alkali metal sulfides may be used alone or in combination of two or more.

[0056] Examples of the dihalobenzene include p-dihalobenzenes such as p-dichlorobenzene and p-dibromobenzene, m-dihalobenzenes such as m-dichlorobenzene, and dihalobenzenes containing a substituent other than a halogen atom, such as 1-methoxy-2,5-dihalobenzene and 3,5-dichlorobenzoic acid. Among these, p-dihalobenzene is preferred, and p-dichlorobenzene is particularly preferred. The dihalobenzenes may be used alone or in combination of two or more.

[0057] The amount of dihalobenzene used (charged amount) is preferably in the range of 0.9 to 2.0 mol, more preferably 1.0 to 1.3 mol, per mol of the alkali metal sulfide charged, in order to obtain a high molecular weight polyphenylene sulfide. By setting the use ratio within the above range, it becomes easy to obtain the polyphenylene sulfide having a high viscosity (high degree of polymerization) suitable for processing.

[0058] In the production of the polyphenylene sulfide, a monohalogen compound (which does not necessarily have to be an aromatic compound) can be used in combination with the dihalobenzene in order to form terminal groups or to adjust the polymerization reaction or molecular weight, etc. Furthermore, in order to form a branched or crosslinked polymer, it is also possible to use in combination a polyhalogen compound (which does not necessarily have to be an aromatic compound) having a trihalogen or higher group, such as 1,2,4-trichlorobenzene or 1,3,5-trichlorobenzene, an active hydrogen-containing halogen aromatic compound, a halogen aromatic nitro compound, or the like.

[0059] In the production of polyphenylene sulfide, it is preferable to add a polymerization aid to the reaction in order to adjust the degree of polymerization. As the polymerization aid, for example, a known polymerization aid generally used as a polymerization aid for polyphenylene sulfide can be used, and examples thereof include alkali metal hydroxides (caustic alkali), alkali metal carboxylates, alkali metal carbonates, alkaline earth metal hydroxides, and alkaline earth metal carbonates. Among these, alkali metal hydroxides and alkali metal carboxylates are preferably used.

[0060] Examples of the alkali metal hydroxide include sodium hydroxide, potassium hydroxide, and lithium hydroxide.

[0061] Examples of the alkali metal carboxylate include lithium acetate, sodium acetate, potassium acetate, sodium propionate, lithium valerate, sodium benzoate, sodium phenylacetate, and potassium p-toluate. Among these, sodium acetate is preferred because it is inexpensive and easily available. The alkali metal carboxylate can be used as an anhydride, a hydrate, or an aqueous solution.

[0062] Alternatively, the alkali metal carboxylate may be formed by adding and reacting an organic acid with one or more compounds selected from the group consisting of alkali metal hydroxides, alkali metal carbonates, and alkali metal bicarbonates in a solvent in approximately equal chemical equivalent amounts.

[0063] The polymerization aids may be used alone or in combination of two or more.

[0064] The amount of the polymerization aid used can be appropriately selected from a wide range depending on the type of polymerization aid, and the types of alkali metal sulfide and dihalobenzene, but is preferably 0.01 mol to 5 mol, and more preferably 0.1 to 2 mol, per 1 mol of the alkali metal sulfide charged.

[0065] As the solvent, it is preferable to use a polar solvent such as an organic amide solvent. Among the organic amide solvents, due to their high reaction stability, amide-based high-boiling polar solvents such as N-alkylpyrrolidones such as N-methyl-2-pyrrolidone and N-ethyl-2-pyrrolidone, caprolactams such as N-methyl-ε-caprolactam, and abrotic organic amide solvents represented by 1,3-dialkyl-2-imidazolidinone, tetraalkylurea, and hexaalkylphosphoric triamide are preferably used. Among these, N-methyl-2-pyrrolidone (hereinafter sometimes abbreviated as NMP) is particularly preferably used.

[0066] The amount of the solvent used is preferably 0.2 to 10 mol, more preferably 2 to 5 mol, per 1 mol of the alkali metal sulfide charged.

[0067] (1) The polyphenylene sulfide can be produced by adding appropriate amounts of the alkali metal sulfide and the dihalobenzene, and, if necessary, appropriate amounts of a halogenated compound other than the dihalobenzene and the polymerization aid, to the polar solvent such as the amide-based high-boiling solvent, and reacting them under high temperature and high pressure.

[0068] The pressure in the polymerization system is appropriately selected depending on the type and amount of the auxiliary used, the desired degree of polymerization, etc. The temperature in the polymerization system and the polymerization time are also appropriately selected depending on the type and amount of the auxiliary used, the desired degree of polymerization, etc., but are preferably 20 minutes to 50 hours at a temperature of 200 to 300°C, and more preferably 1 to 10 hours at a temperature of 230 to 280°C.

[0069] In this manner, powdery or granular polyphenylene sulfide is obtained. The obtained powdery or granular polyphenylene sulfide is then washed with water and / or a solvent to separate by-product salts, polymerization aids, unreacted monomers, etc.

[0070] (2) When a resin other than polyphenylene sulfide (resin composition (A)) or particles is added to the polyphenylene sulfide film of the present invention as described above, the resin composition (A) or particles are first mixed with the powdery or granular polyphenylene sulfide and uniformly mixed using a Henschel mixer, etc. When additives such as antioxidants, heat stabilizers, lubricants, and ultraviolet absorbers are added, they are also mixed with polyphenylene sulfide in the same manner.

[0071] The resulting mixture is then fed to an extruder, preferably an extruder having one or more vent holes, melt-kneaded at a temperature of 290 to 360°C, and extruded through an appropriate die to obtain a polyphenylene sulfide resin composition. Alternatively, the mixture may be melt-molded into a gut shape and cut into lengths of about 2 to 10 mm to obtain a pellet-shaped polyphenylene sulfide resin composition. The resulting polyphenylene sulfide resin composition is dried in a heated dryer under vacuum at a temperature of 100 to 180°C for about 1 to 5 hours.

[0072] In addition, when the resin composition (A) or particles are not added, additives such as antioxidants, heat stabilizers, lubricants, and ultraviolet absorbers can be mixed with the polyphenylene sulfide obtained in (1) as needed, and the mixture can be extrusion-molded or melt-molded in the same manner as in the case of a mixture containing the resin composition (A) or particles, and used as a polyphenylene sulfide resin composition.

[0073] The polyphenylene sulfide resin composition may be used singly or in a mixture of two or more thereof. For example, polyphenylene sulfide resin pellets to which the resin composition (A) has been added (hereinafter also referred to as master pellets) may be mixed with polyphenylene sulfide resin pellets to which the resin composition (A) or particles have not been added (hereinafter also referred to as base pellets).

[0074] (3) Next, the polyphenylene sulfide resin pellets obtained in (2) are used to produce the polyphenylene sulfide film of the present invention. The polyphenylene resin pellets obtained in (2) are stirred in a mixer under reduced pressure, preferably at a vacuum of 0 to 50 mmHg, while being heated to a temperature of 120 to 230°C, preferably 160 to 200°C, and dried for at least 3 hours, preferably 5 to 10 hours. Insufficient reduced pressure can lead to crosslinking of polyphenylene sulfide resin molecules with oxygen, resulting in the formation of modified polymers. Drying temperatures above 230°C can cause the dried raw materials to solidify, potentially interfering with film formation. Temperatures below 120°C can leave impurities in the polyphenylene sulfide raw materials, particularly high-boiling compounds that volatilize when heated to around 250°C, which can cause film defects.

[0075] The drying of the polyphenylene sulfide resin composition may be carried out in multiple stages, such as by drying the polyphenylene sulfide resin composition as described above, gradually cooling it back to room temperature, and then drying it again.

[0076] Next, the dried polyphenylene sulfide resin composition is used to prepare the polyphenylene sulfide film of the present invention, which may be a single layer or a composite layer. When preparing a composite film, the lamination method can be coating, laminating, coextrusion, or the like. Among these, coextrusion lamination is preferred in terms of controlling the thickness of each layer constituting the polyphenylene sulfide film of the present invention.

[0077] The polyphenylene sulfide film of the present invention is preferably produced as follows. First, the polyphenylene sulfide resin composition is supplied to a melt extrusion device and melted by heating to a temperature above the melting point of the polyphenylene sulfide resin composition, preferably 290 to 360°C. Next, the melt is extruded from a slit-shaped die outlet and rapidly cooled and solidified (cast) onto a rotating metal drum called a casting roll to produce an unstretched film. At this time, it is preferable to install a gear pump, a static mixer, and a filtration device in the polymer flow path.

[0078] The obtained unstretched film can be stretched to form a stretched film by a sequential biaxial stretching method in which stretching is performed sequentially in the film longitudinal direction (machine direction) and the film width direction (transverse direction) using a group of rolls and a tenter, or a simultaneous biaxial stretching method in which stretching is performed simultaneously in the film longitudinal direction and the film width direction, etc. Among the stretching methods, the sequential biaxial stretching method is preferred.

[0079] The stretching conditions when using the sequential biaxial stretching method can be appropriately selected from a wide range depending on various conditions such as the type of polyphenylene sulfide contained in the polyphenylene sulfide resin composition and the presence and type of other resins and additives, but it is preferable to stretch the film in the longitudinal direction (machine direction) at a stretching ratio of 3.3 to 5.0 times, more preferably 3.5 to 4.4 times, and in the width direction (transverse direction) at a stretching ratio of 2.5 to 4.5 times, more preferably 3.0 to 4.0 times, at a temperature of 80 to 120° C., more preferably 90 to 110° C. The ratio of the stretching ratio in the width direction (transverse direction) to the stretching ratio in the longitudinal direction (machine direction) is preferably 0.8 to 1.4, more preferably 1.0 to 1.2.

[0080] Furthermore, as a method of heating the film during longitudinal stretching, it is more preferable to heat the film using a radiation heater in addition to heating by heat conduction from the conveying rolls, and adjust the temperatures of both sides of the film within an appropriate range, as this leads to control of the molecular orientation of polyphenylene sulfide.

[0081] The resulting stretched film is preferably further subjected to a heat treatment. The heat treatment conditions can be appropriately selected from a wide range depending on various conditions, such as the type of polyphenylene sulfide contained in the polyphenylene sulfide resin composition, and the presence and type of other resins and additives. However, from the viewpoint of heat resistance, mechanical properties, and thermal dimensional stability, it is preferable to perform the heat treatment at a temperature of 180°C or higher and lower than the melting point of the polyphenylene sulfide composition, more preferably 200°C or higher and 5°C lower than the melting point of the polyphenylene sulfide resin composition, for 1 to 60 seconds under a constant length or limited shrinkage of 15% or less. Furthermore, to improve the thermal dimensional stability of the film, relaxation in one or both directions is also possible. In particular, relaxing the film by 3.0% to 9.0% in the width direction facilitates reducing the dimensional change rate, and is preferred for achieving a widthwise elongation at 230°C measured by TMA within the range specified in the present application. Relaxing the film by 5.5% to 8.0% in the width direction is more preferable. The relaxation temperature is preferably 220°C or higher and lower than the melting point of the polyphenylene sulfide composition, more preferably 250°C or higher, and is preferably in the range of the melting point (°C) of the polyphenylene sulfide resin composition minus 10°C in order to bring the width direction elongation at 230°C measured by TMA within the range specified in the present application. It is preferable to re-stretch the relaxed film in the width direction (transverse direction) in order to improve the in-plane uniformity of dimensional change. The re-stretching ratio is preferably 0.2% or higher and 7.0% or lower, more preferably 1.0% or higher and 3.5% or lower. If the re-stretching ratio is less than 0.2%, the effect of improving the in-plane uniformity of dimensional change by suppressing bowing cannot be obtained, and if it exceeds 7.0%, film tearing may occur, resulting in a decrease in productivity. The re-stretching temperature is preferably at least 30°C above the crystallization temperature Tcc (°C) of the polyphenylene sulfide resin composition and not more than 90°C above the crystallization temperature Tcc (°C) of the polyphenylene sulfide resin composition, in order to bring the differences between the maximum and minimum values ​​of the elongation percentages in the longitudinal direction, 45° direction, width direction, and 135° direction at 150°C, measured by TMA, into the range specified in the present application, and more preferably at least 40°C above the crystallization temperature Tcc (°C) of the polyphenylene sulfide resin composition and not more than 80°C above the crystallization temperature Tcc (°C) of the polyphenylene sulfide resin composition.

[0082] The polyphenylene sulfide film after re-stretching is cooled in a conveying process, and then the edges are cut and wound up to obtain an intermediate product, which is then slit into an appropriate width and length in a slitting process and wound up to obtain the polyphenylene sulfide film roll of the present invention.

[0083] The polyphenylene sulfide film of the present invention may be subjected to a corona discharge treatment or a plasma treatment to impart stronger interfacial adhesion to the metal layer. The atmospheric gas used during the corona discharge treatment may be at least one gas selected from air (EC treatment), oxygen (OE treatment), nitrogen (NE treatment), carbon dioxide (CE treatment), etc. Of these, in the present invention, surface treatment by EC treatment is more preferable from the viewpoint of economic efficiency. These surface treatments may be performed during the polyphenylene sulfide film formation process or in a separate process from the film formation process, and are preferably performed during the film formation process from the viewpoint of economic efficiency.

[0084] The polyphenylene sulfide film of the present invention is preferably formed into a metallized film by providing a metal layer on at least one side of the polyphenylene sulfide film, due to its excellent processability during vapor deposition and lamination of a metal layer. Metallized films can be used as capacitors and circuit substrates, as well as current collector foils, due to their excellent processability even when thinned. To form a metallized film, a metal layer must be provided on at least one surface, and the metal may be one or more of copper, copper alloy, aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, or silver alloy. For lithium-ion batteries, the metal layer is preferably aluminum for the positive electrode current collector foil, and copper for the negative electrode current collector foil. For sodium-ion batteries, the positive electrode current collector foil may be aluminum and the negative electrode current collector foil may be copper, or both the positive and negative electrode current collector foils may be aluminum. Preferred methods for forming the metal layer include vacuum vapor deposition, sputtering, electrolytic plating, and electroless plating, and these methods may also be combined.

[0085] The metallized film of the present invention can be used as an electrode plate by forming an electrode material layer on at least one surface. Examples of electrode materials include lithium-containing metal oxides such as lithium cobalt oxide, lithium manganese oxide, and lithium nickel oxide, and lithium-containing metal phosphates such as lithium iron phosphate and lithium iron manganese phosphate for the positive electrode of lithium-ion batteries. Examples of active materials include sodium-containing metal oxides, sodium-containing metal phosphates, and sodium-containing Prussian blue analogs for the positive electrode of sodium-ion batteries. Acetylene black, ketjen black, carbon nanotubes, and graphene may also be used as conductive materials, and polyvinylidene fluoride may be used as binders. Examples of active materials that can be used for negative electrodes include graphite, carbon black, acetylene black, hard carbon, soft carbon, carbon nanotubes, and graphene; lithium alloy materials such as tin and silicon; lithium titanate; and metallic lithium, with binders such as carboxymethyl cellulose, styrene-butadiene copolymer, and polyvinylidene fluoride.

[0086] To prepare electrodes, an electrode coating solution is first prepared by dispersing an active material and a conductive additive in a binder resin solution. This coating solution is then applied to a metal foil or metallized film, and the solvent is dried to obtain a positive electrode and a negative electrode, respectively. The thickness of the coating film after drying is preferably 30 μm to 500 μm. Furthermore, it is preferable to apply pressure to the active material layer formed on the metallized film using a rolling method such as a roll press method to densify the active material layer. The active material layer may also be further densified by heating the roll during rolling. Since the metallized film of the present invention has excellent dimensional stability at high temperatures, it is possible to prepare electrodes with excellent flatness even at high temperatures during solvent drying, thereby improving productivity. Furthermore, the storage modulus E' at 90°C in the longitudinal direction is MD90 and the storage modulus E' at 100 ° C in the longitudinal direction MD100 The storage modulus ratio is 0.93≦E′ MD100 / E' MD90 When the ratio is ≦0.98, dimensional change is small even when the pressure of the roll press is increased, and peeling between the metal layer and the film and the occurrence of wrinkles can be suppressed.

[0087] A laminate having a plurality of electrode groups each having a positive electrode and a negative electrode sandwiched between them and a separator for a lithium secondary battery so as to contact the active material layer of each electrode, or a wound assembly having a positive electrode, a separator, and a negative electrode stacked together and wound up, can be enclosed in an exterior material such as a metal can or an aluminum laminate film to form a secondary battery. The metallized film of the present invention has a stress F2 at 2% elongation and a stress F5 at 5% elongation at room temperature of 23°C that satisfy the relationship 36 MPa < F5 - F2 ≦ 54 MPa in the longitudinal direction, thereby exhibiting excellent dimensional stability against tensile stress during winding, and enabling the production of a stable wound assembly with little shear even during high-speed, high-tension winding.

[0088] The polyphenylene sulfide film roll thus obtained can be rewound while laminating the necessary layers to form a metallized film roll, a current collecting foil roll, and an electrode plate roll, and then wound up.

[0089] The polyphenylene sulfide film of the present invention can be used in various industrial applications, and because it combines the heat resistance and chemical resistance characteristics of polyphenylene sulfide resin, it is particularly suitable for use in current collector foil applications. Furthermore, the polyphenylene sulfide film of the present invention can suppress the occurrence of wrinkles in the film when exposed to high temperatures and tension is applied in the machine direction, making it suitable for applications in which a metal layer is provided on at least one side of the film at a thickness of 1 μm to 10 μm by a single roll-to-roll vapor deposition. Furthermore, because the variation in elongation at temperatures around 150°C is small, it can be further suitable for applications in which an electrode material layer is provided on the metal layer at temperatures of 150°C or less.

[0090] [Measurement Method] (1) Thickness The cross section of the film was cut using a microtome (electric microtome ST-201 manufactured by Japan Microtome Laboratory), and the sliced ​​pieces were observed under a transmitted light microscope to measure the thickness [μm].

[0091] (2) Thermomechanical Analysis (TMA) A polyphenylene sulfide film roll was cut into 50 mm × 50 mm samples in the longitudinal and transverse directions at Point A, which was 50 mm from one end toward the center, and Point B, which was 50 mm from the other end toward the center. A measurement sample measuring 20 mm in length and 5 mm in width was taken from the obtained sample.

[0092] Measurements were performed under the following conditions using a thermomechanical analyzer (TM-9300) manufactured by ULVAC-RIKO Corporation. One data point was obtained per 1°C, and the elongation (%) at each temperature was calculated. Measurement directions were the longitudinal direction, 45° direction, width direction, and 135° direction, with the 45° direction being the direction rotated 45° clockwise from the longitudinal direction, and the 135° direction being the direction rotated 45° counterclockwise from the longitudinal direction. Measurements were performed N=3 times in each of the four directions at points A and B, and the largest value was adopted as the elongation (%) of the polyphenylene sulfide film roll in the longitudinal direction, 45° direction, width direction, and 135° direction. Measurement temperature range: 30°C to 250°C; Heating rate: 10°C / min; Measurement load: 10 g; Measurement room environment: Temperature 23°C, relative humidity 65%, in air.

[0093] (3) Differential Scanning Calorimetry (DSC) Samples of 50 mm x 50 mm were cut out in the longitudinal and width directions of the polyphenylene sulfide film roll at point A, which was 50 mm from one end toward the center, and at point B, which was 50 mm from the other end toward the center.

[0094] A 5 mg sample was scraped off from the cut specimen and weighed into a sample pan. The sample was measured using a differential scanning calorimeter (TA Instruments DSC Q100) by heating from 25°C to 350°C at a heating rate of 20°C / min. The crystallinity was calculated from the obtained differential scanning calorimeter chart using the heat of crystalline fusion (ΔHm) and the heat of cold crystallization (ΔHc) according to the following formula: Crystallinity [%] = (ΔHm - ΔHc) / ΔHm0 × 100

[0095] Here, the literature value of the heat of fusion of perfectly crystalline polyphenylene sulfide, 146.44 J / g (Maemura E., Cakmak M., White J.L., Polym. Eng. Sci., 29, 140 (1989)), was used as ΔHm0.

[0096] The crystallization temperature Tcc was determined as the peak temperature of the exothermic peak due to crystallization from the glass state obtained by heating the sample from 25°C to 350°C at a heating rate of 20°C / min, holding the temperature for 5 minutes, then rapidly cooling it with liquid nitrogen for 5 minutes, and reheating the same sample from 25°C to 350°C at a heating rate of 20°C / min.

[0097] The average values ​​of the degree of crystallinity and the crystallization temperature Tcc at points A and B were taken as the values ​​for the polyphenylene sulfide film roll.

[0098] (4) Tensile Test A polyphenylene sulfide film roll was cut into 250 mm x 250 mm samples in the longitudinal and transverse directions at point A, which was 50 mm from one end toward the center, and point B, which was 50 mm from the other end toward the center. A measurement sample measuring 230 mm in length and 10 mm in width was taken from the obtained samples.

[0099] In accordance with JIS-C2151 (2019), the stress at 2% elongation (F2) and the stress at 5% elongation (F5) were measured using Orientec's "TENSILON" (registered trademark) UCT-100 at room temperature of 23 ° C. and a relative humidity of 65%. Specifically, a strip-shaped sample having a length of 230 mm and a width of 10 mm was measured five times at a test length of 100 mm and a tensile speed of 200 mm / min, and the average values ​​were taken as the stress at 2% elongation (F2) and the stress at 5% elongation (F5). The average values ​​of points A and B for the stress at 2% elongation (F2) and the stress at 5% elongation (F5) were taken as the values ​​for the polyphenylene sulfide film roll.

[0100] The film was cut at 100 mm intervals across a 700 mm width, centered at the center in the width direction, to a size of 230 mm in length and 10 mm in width, and a tensile test was performed at a test length of 100 mm and a pulling speed of 200 mm / min. The tensile modulus was calculated from the maximum elasticity immediately before deformation (a linear equation of the tangent to the maximum slope of the SS curve). Similarly, the longitudinal tensile modulus was measured at eight locations in the width direction, and the difference between the maximum and minimum longitudinal tensile modulus in the width direction was calculated.

[0101] (5) Molecular Orientation Meter Samples of 40 mm x 40 mm were cut out in the longitudinal and transverse directions of the polyphenylene sulfide film roll at point A, which was 50 mm from one end toward the center, and at point B, which was 50 mm from the other end toward the center.

[0102] The dielectric constant ε' in the longitudinal direction was measured using a microwave transmission type molecular orientation analyzer MOA-6015 (manufactured by Oji Scientific Instruments Co., Ltd.) at a frequency of 15 GHz. MD The molecular orientation ratio (MOR) and the molecular orientation ratio (MOR) were measured. The corrected molecular orientation ratio (MOR_c) was calculated from the obtained MOR using the following formula: MOR_c = (MOR - 1) x tc / t + 1

[0103] Here, t is the sample thickness (μm), tc is the reference thickness to be corrected (4 μm), MOR is the ratio of the major axis to the minor axis of the polar coordinate (orientation pattern) obtained by the above measurement, and MOR_c is the corrected MOR.

[0104] ε′ MD The average value of points A and B was used as the value of the polyphenylene sulfide film roll for MOR_c, and the larger value of points A and B was used as the value of the polyphenylene sulfide film roll for MOR_c.

[0105] (6) Dynamic Viscoelasticity Measuring Apparatus (DMA) A polyphenylene sulfide film roll was cut into 50 mm x 50 mm samples in the longitudinal and transverse directions at Point A, which was 50 mm from one end toward the center, and Point B, which was 50 mm from the other end toward the center. A measurement sample measuring 20 mm in length and 10 mm in width was then taken from the obtained samples.

[0106] Both ends of the obtained strip-shaped sample were set on chucks with a chuck distance of 10 mm, and the sample was subjected to measurement. MD90 and storage modulus E' at 100 ° C. MD100 The storage modulus E' was measured at each temperature during the heating process. MD90 , E' MD100 In both cases, the average value of points A and B was taken as the value of the polyphenylene sulfide film roll. Apparatus: EXSTAR DMS6100 (manufactured by Seiko Instruments Inc.) Measurement mode: tension Measurement temperature range: 25°C to 200°C Heating rate: 2°C / min Measurement atmosphere: air Frequency: 1 Hz Displacement: 10.0 µm

[0107] (7) Wrinkles During Vapor Deposition of Metal Layer Twenty polyphenylene sulfide film rolls of the present invention obtained by the method described below were prepared. Each polyphenylene sulfide film roll was vacuum-deposited with copper at a conveying speed to a thickness of 1.0 μm using a high-frequency dielectric heating vacuum deposition method, with a cooling can roll temperature of 50°C, and then wound up under a tension of 35 N / m. Rolls that did not develop wrinkles due to thermal dimensional changes during vacuum deposition were considered pass, and rolls that developed wrinkles were considered fail. The number of pass rolls out of the 20 was evaluated according to the following criteria. Rolls that had visible wrinkles of 0.5 mm or more in width and 20 cm or more in length on the surface of the roll during the conveying process or after winding were considered to have wrinkles. A: 20 out of 20 passed. B: 19 out of 20 passed, 1 failed. C: 16 to 18 out of 20 passed, 2 to 4 failed. D: 15 or less passed, 5 or more failed out of 20.

[0108] (8) Winding property when forming a metal layer by vapor deposition A polyphenylene sulfide film roll of the present invention obtained by the method described below was subjected to vacuum deposition in the same manner as in (7) and then wound up. The amount of film slippage at the end face of the polyphenylene sulfide film roll after winding, which was caused by meandering due to thermal dimensional changes during vacuum deposition, was evaluated according to the following criteria: A: The amount of film slippage at the end face was less than 2 mm; B: The amount of film slippage at the end face was 2 mm or more but less than 5 mm; C: The amount of film slippage at the end face was 5 mm or more but less than 10 mm; D: The amount of film slippage at the end face was 10 mm or more.

[0109] (9) Processability during electrode material layer formation A metal layer was formed on the polyphenylene sulfide film roll of the present invention obtained by the method described below using the method (7). The surface of the metal layer of the accepted polyphenylene sulfide film roll was thoroughly stirred with deionized water in a mass ratio of 97.5:1.0:1.5, and a slurry with a solids concentration of 50% by mass was applied by roll-to-roll coating to a dry thickness of 50 μm. The resulting electrode layer was then dried at 130 °C to form an electrode material layer. For the obtained electrode material layer, samples measuring 20 mm in length and 20 mm in width were collected at equal intervals from 20 locations in the width direction between a position 10 mm from one end of the width direction and a position 10 mm from the other end of the width direction. The thickness [μm] of the electrode material layer was measured for the collected samples using the same method as in (1), and the difference between the maximum and minimum values ​​at 20 locations in the width direction was evaluated according to the following criteria. A: The difference between the maximum and minimum values ​​at 20 locations in the width direction is less than 1.2 μm. B: The difference between the maximum and minimum values ​​at 20 locations in the width direction is 1.2 μm or more and less than 2.5 μm. C: The difference between the maximum and minimum values ​​at 20 locations in the width direction is 2.5 μm or more and less than 5.0 μm. D: The difference between the maximum and minimum values ​​at 20 locations in the width direction is 5.0 μm or more.

[0110] (10) Peeling and wrinkles during formation of rolled electrode An electrode material layer was formed on a polyphenylene sulfide film roll of the present invention obtained by the method described below using methods (7) and (9). Using the electrodes that passed the test, roll pressing was performed using a roll-to-roll method so that the thickness of the electrode layer became 35 μm, to form a rolled electrode. Twenty samples of the rolled electrode, each 500 mm long, were taken. The taken samples were evaluated for peeling and wrinkles between the electrode material layer and the metal layer according to the following criteria: A: Fewer than one peeled area and wrinkle out of 20 samples; B: Fewer than three peeled areas and wrinkles out of 20 samples; C: Three or more peeled areas and wrinkles out of 20 samples.

[0111] (11) Winding property during winding formation Rolled electrodes were formed on the polyphenylene sulfide film roll of the present invention obtained by the method described below by methods (7), (9), and (10), and 20 wound bodies were sampled using the acceptable rolled electrodes. The sampled samples were evaluated for the misalignment between the positive and negative electrodes in the short-side direction according to the following criteria: A: Of the 20 wound bodies, 18 or more wound bodies had a misalignment between the positive and negative electrodes in the short-side direction of 2 mm or less; B: Of the 20 wound bodies, 15 to less than 18 wound bodies had a misalignment between the positive and negative electrodes in the short-side direction of 2 mm or less; C: Of the 20 wound bodies, less than 15 wound bodies had a misalignment between the positive and negative electrodes in the short-side direction of 2 mm or less.

[0112] [Production of Resin Powder and Pellets] (Production of Polyphenylene Sulfide Powder) A 70 L autoclave equipped with a stirrer was charged with 8.181 kg (70.00 mol) of a 48% by mass aqueous sodium hydrosulfide solution, 2.943 kg (70.63 mol) of 96% pure sodium hydroxide, 11.45 kg (115.5 mol) of N-methyl-2-pyrrolidone (NMP), 2.239 kg (27.30 mol) of anhydrous sodium acetate, and 4.900 kg (272.2 mol) of ion-exchanged water. The mixture was gradually heated to 240 ° C. over approximately 3 hours under atmospheric pressure while passing nitrogen through the mixture. 9.12 kg of water and 0.14 kg of NMP were distilled off, and the reaction vessel was then cooled to 160 ° C. The stirring speed in this reaction was 240 revolutions per minute (240 rpm).

[0113] The total amount of water remaining in the system and the amount of water consumed in the hydrolysis of NMP per mole of the alkali metal sulfide charged was 72.0 moles. In addition, 0.020 moles of hydrogen sulfide was released outside the reaction system per mole of the alkali metal sulfide charged.

[0114] Next, 10.29 kg (69.97 mol) of p-dichlorobenzene (p-DCB) and 9.090 kg (91.70 mol) of NMP were added to the reaction system. After the reaction vessel was sealed under nitrogen gas, the temperature was increased from 200°C to 227°C at a rate of 0.8°C / min while stirring at 400 rpm, and then the temperature was increased from 227°C to 270°C at a rate of 0.6°C / min, and the temperature was maintained at 270°C for 140 minutes.

[0115] Thereafter, 2.346 kg (130.3 mol) of ion-exchanged water was added to the system over 15 minutes while gradually cooling the reaction system to 250° C. Next, the reaction system was gradually cooled from 250° C. to 200° C. at a rate of 1.0° C. / min, and then rapidly cooled to near room temperature.

[0116] The resulting polyphenylene sulfide was washed with 15 kg (bath ratio 1:15) of N-methyl-2-pyrrolidone solvent per 1 kg of the theoretical amount at 90°C for 1.5 hours, followed by filtration. The resulting cake was washed twice with ion-exchanged water (bath ratio 1:15) at 70°C for 1.5 hours and filtered. It was then washed and filtered twice with ion-exchanged water (bath ratio 1:15) containing 1% by mass of calcium acetate at 70°C for 1.5 hours, and then washed and filtered twice again with ion-exchanged water (bath ratio 1:15) at 70°C for 1.5 hours.

[0117] The resulting polymer was dried at 150°C under vacuum for 4 days to obtain a polyphenylene sulfide powder having a melting point of 285°C and a crystallization temperature Tcc of 140°C.

[0118] The melt flow rate was measured in accordance with JIS-K7210 (1999) using a melt indexer manufactured by Toyo Seiki Seisakusho, Ltd., with an orifice having a hole diameter of 2.095 mm and a length of 8.00 mm, under conditions of a temperature of 315.6°C and a load of 5000 g. Approximately 7 g of sample was placed in the apparatus, and after 1 minute, a piston was inserted. After a further 4 minutes, a load was placed on the piston, and the melt flow rate calculated from the weight of polymer flowing out per unit time was 70 g / 10 min.

[0119] (Preparation of Particle Master Pellets) A slurry was prepared by dispersing 50% by mass of calcium carbonate particles with an average particle size of 1.0 μm in ethylene glycol. After filtering the slurry, the polyphenylene sulfide powder was mixed with the above-mentioned mixture using a Henschel mixer so that the calcium carbonate content was 7.0% by mass. The resulting mixture was melt-extruded to obtain particle pellets with a particle content of 7.0% by mass. This will be referred to as PPS resin A hereinafter.

[0120] (Preparation of Particle-Free Pellets) The above polyphenylene sulfide powder polymer alone was melt-extruded to obtain base pellets of polyphenylene sulfide resin, which will be hereinafter referred to as PPS resin B.

[0121] [Example 1] PPS resin A and PPS resin B were mixed so that the calcium carbonate content was 1.0 mass % relative to the total amount of resin, and then dried at a temperature of 180°C under a reduced pressure of 3 mmHg for 4 hours using a rotary vacuum dryer.

[0122] The dried pellets were fed to a single-screw extruder, melted at 310°C, and extruded through a T-die nozzle into a sheet. The sheet was then wound around a casting drum at a surface temperature of 25°C using an electrostatic casting method, and cooled and solidified to produce an unstretched film.

[0123] The resulting unstretched film was stretched 3.7 times in the longitudinal direction using a sequential biaxial stretching method. Both sides of the film were heated to 100°C using a heated conveying roll and a radiation heater, and then stretched 3.4 times in the width direction at 100°C through a tenter. The film was then heat-treated at 265°C in a heat treatment chamber following the tenter used for stretching in the width direction, and relaxed in the width direction at 260°C under a limited shrinkage of 7.5%. The relaxed film was then re-stretched 1.5% in the width direction at 200°C in a cooling chamber following the tenter heat treatment chamber, and wound around a core to obtain a polyphenylene sulfide film intermediate product with a thickness of 4 μm and a width of 2500 mm. This film was then slit to obtain film rolls as shown in the table.

[0124] Examples 2 and 3 A film roll was obtained in the same manner as in Example 1, except that it was slit as shown in the table.

[0125] Example 4 A polyphenylene sulfide film was obtained in the same manner as in Example 2, except that the re-stretching ratio was set to 4.0%, and then slit to obtain a film roll.

[0126] Example 5 A polyphenylene sulfide film was obtained in the same manner as in Example 2, except that the re-stretching ratio was set to 0.5%, and then slit to obtain a film roll.

[0127] Example 6 A polyphenylene sulfide film was obtained in the same manner as in Example 2, except that the relaxation rate was set to 5.0%, and then slit to obtain a film roll.

[0128] Example 7 A polyphenylene sulfide film was obtained in the same manner as in Example 2, except that the relaxation rate was set to 8.5%, and then slit to obtain a film roll.

[0129] Example 8 A polyphenylene sulfide film was obtained in the same manner as in Example 2, except that the re-stretching temperature was set to 240° C., and then slit to obtain a film roll.

[0130] Example 9 A polyphenylene sulfide film was obtained in the same manner as in Example 2, except that the re-stretching temperature was set to 160° C., and then slit to obtain a film roll.

[0131] Example 10 A polyphenylene sulfide film was obtained in the same manner as in Example 2, except that the relaxation temperature was set to 240° C., and then slit to obtain a film roll.

[0132] Example 11 A polyphenylene sulfide film was obtained in the same manner as in Example 2, except that the longitudinal stretching ratio was 3.4 times, the transverse stretching ratio was 3.7 times, and the re-stretching ratio was 4.0%, and then slit to obtain a film roll.

[0133] Example 12 A polyphenylene sulfide film was obtained in the same manner as in Example 2, except that the extrusion rate was adjusted to a thickness of 2 μm, and the film was slit to obtain a film roll.

[0134] Example 13 A polyphenylene sulfide film was obtained in the same manner as in Example 2, except that the extrusion rate was adjusted to a thickness of 9 μm, and the film was slit to obtain a film roll.

[0135] Example 14 A polyphenylene sulfide film was obtained in the same manner as in Example 2, except that the extrusion rate was adjusted to a thickness of 12 μm, and the film was slit to obtain a film roll.

[0136] Example 15 A polyphenylene sulfide film was obtained in the same manner as in Example 2, except that the extrusion rate was adjusted to a thickness of 25 μm, and the film was slit to obtain a film roll.

[0137] Comparative Example 1 A polyphenylene sulfide film was obtained in the same manner as in Example 2, except that the film after the relaxation treatment was not re-stretched, and then slit into a film roll.

[0138] Comparative Example 2 A polyphenylene sulfide film was produced in the same manner as in Example 2 except that the re-stretching ratio was set to 7.5%, but the film broke and could not be collected.

[0139] Comparative Example 3 A polyphenylene sulfide film was obtained in the same manner as in Example 2 except that the relaxation rate was set to 1.5%, and then slit to obtain a film roll.

[0140] Comparative Example 4 A polyphenylene sulfide film was obtained in the same manner as in Example 2 except that the relaxation rate was set to 9.5%, and then slit to obtain a film roll.

[0141] Comparative Example 5 A polyphenylene sulfide film was obtained in the same manner as in Example 2 except that the re-stretching temperature was set to 260° C., and then slit to obtain a film roll.

[0142] Comparative Example 6 A polyphenylene sulfide film was obtained and slit into a film roll in the same manner as in Example 2, except that the re-stretching temperature was set to 140° C. Since the re-stretching was performed at a temperature lower than 150° C., the effect of making the elongation at 150° C. measured by TMA uniform in-plane was not obtained.

[0143] Comparative Example 7 A polyphenylene sulfide film was obtained and slit into a film roll in the same manner as in Example 2, except that the relaxation temperature was 210° C. Since the relaxation treatment was performed at a temperature lower than 230° C. and closer to 150° C., the elongation in the width direction at 230° C. decreased and the elongation in the width direction at 150° C. increased.

[0144] [Comparative Example 8] A polyphenylene sulfide film obtained in the same manner as in Comparative Example 1 was attached to the delivery section of a roll-support type coater, and the film was passed through a drying oven heated to 200°C and continuously heated to obtain a heat-treated polyphenylene sulfide film. The heating time was 60 seconds. During heating, the tensile stress applied to the polyphenylene sulfide film in the winding direction by winding with a winder was 0.1 kgf, equivalent to a film having a cross-sectional area of ​​1 m wide and 40 μm thick. Furthermore, heating was performed without applying any particular force in the lateral direction.

[0145] The properties of the polyphenylene sulfide films obtained in the examples and comparative examples are shown in the table below.

[0146]

[0147]

[0148]

[0149]

[0150]

[0151]

[0152]

[0153]

[0154]

[0155]

[0156] The polyphenylene sulfide film of the present invention can be used in various industrial applications, and since it has the heat resistance and chemical resistance that are characteristics of polyphenylene sulfide resin, it can be particularly suitably used as a current collector foil.

Claims

1. A film mainly composed of polyphenylene sulfide resin, having an elongation rate in the width direction at 230 °C measured by thermomechanical analysis (TMA) of 0.0% or more and 13.0% or less, and the difference between the maximum value and the minimum value of the elongation rates in the longitudinal direction, 45° direction, width direction, and 135° direction at 150 °C measured by TMA is 1.6% or less. A polyphenylene sulfide film.

2. The polyphenylene sulfide film according to claim 1, wherein the change amount of the elongation rate in the width direction in the range of 150 °C to 230 °C measured by TMA is 0.0% or more and 8.0% or less.

3. The polyphenylene sulfide film according to claim 1, wherein the elongation rates in the longitudinal direction, 45° direction, width direction, and 135° direction at 230 °C measured by TMA for a film sample cut out to 50 mm × 50 mm in the longitudinal and width directions of the film are all 0.0% or more and 9.0% or less.

4. The polyphenylene sulfide film according to claim 1, wherein the crystallinity determined from the heat of fusion enthalpy measured using a differential scanning calorimeter (DSC) is 29% or more and 40% or less.

5. The polyphenylene sulfide film according to claim 1, wherein the stress F2 at an elongation of 2% and the stress F5 at an elongation of 5% when a tensile test of the film is performed at room temperature of 23 °C satisfy the following formula in the longitudinal direction. 36.0 [MPa] < F5 - F2 ≤ 54.0 [MPa] 6. Dielectric constant ε′ in the longitudinal direction measured using a molecular orientation meter MD is 3.00 or more and 3.30 or less, and MOR_c (Corrected Molecular Orientation Ratio) is 1.00 or more and 1.30 or less. The polyphenylene sulfide film according to claim 1.

7. The storage modulus E' at 90°C in the longitudinal direction measured using a dynamic viscoelasticity measuring device (DMA) under the conditions of a measurement temperature from 25°C to 200°C, a heating rate of 2°C / min, a frequency of 1 Hz, and a displacement of 10 μm MD90 [GPa] and the storage modulus E' at 100°C in the longitudinal direction MD100 [GPa] satisfies the following relationship: The polyphenylene sulfide film according to claim 1, 0.93 ≤ E' MD100 / E' MD90 ≤ 0.98 8. The polyphenylene sulfide film according to claim 1, wherein the crystallization temperature Tcc measured using a differential scanning calorimeter (DSC) is 136 °C or more and 155 °C or less.

9. The polyphenylene sulfide film according to claim 1, wherein the content ratio of the polyphenylene sulfide resin is more than 98% by mass and 100% by mass or less based on the mass of all components constituting the polyphenylene sulfide film.

10. The polyphenylene sulfide film according to claim 1, wherein the melt flow rate of the polyphenylene sulfide resin measured under the conditions of a temperature of 315.6 °C and a load of 5000 g is 40 g / 10 min or more and 100 g / 10 min or less.

11. The polyphenylene sulfide film according to claim 1, having a thickness of 1 μm or more and 30 μm or less.

12. A metallized film formed by providing a metal layer on at least one side of the polyphenylene sulfide film according to any one of claims 1 to 11.

13. A current collector foil having a metal layer provided on at least one side of the polyphenylene sulfide film according to any one of claims 1 to 11.

14. An electrode plate having an electrode material layer formed on the surface of the current collector foil according to claim 13.

15. A secondary battery using the electrode plate according to claim 14.

16. A film roll formed by winding a film mainly composed of polyphenylene sulfide and having a width of 700 mm or more. At point A located at a position 50 mm from one end of the roll to the center and point B located at a position 50 mm from the other end of the roll to the center, the elongation rate in the width direction at 230 °C measured by thermomechanical analysis (TMA) of a film sample cut out to 50 mm × 50 mm in the longitudinal and width directions of the film roll is 0.0% or more and 13.0% or less in both cases. Among the elongation rates in the longitudinal, 45°, width, and 135° directions at 150 °C measured by TMA, the difference between the maximum value and the minimum value is 1.6% or less in all cases. A polyphenylene sulfide film roll.

17. The polyphenylene sulfide film roll according to claim 16, wherein the difference in the elongation rate in the 45° direction at 230 °C measured by TMA at points A and B is 1.2% or less, and the difference in the elongation rate in the 135° direction at 230 °C is 1.2% or less.

18. The polyphenylene sulfide film roll according to claim 16, wherein the amount of change in the elongation rate in the width direction in the range from 150 °C to 230 °C measured by TMA at points A and B is 0.0% or more and 8.0% or less in both cases.

19. The polyphenylene sulfide film roll according to claim 16, wherein the difference between the maximum value and the minimum value of the longitudinal tensile elastic modulus in the width direction of the film determined by the following measurement method is 5 MPa or more and 60 MPa or less in a 700 mm width centered on the central portion in the film width direction. (Measurement method) Cut out samples with a length of 230 mm and a width of 10 mm at intervals of 100 mm over a 700 mm width centered on the central portion in the film width direction. Measure the longitudinal tensile elastic modulus in the width direction at 8 locations with a test length of 100 mm and a tensile speed of 200 mm / min, and determine the difference between the maximum value and the minimum value of the longitudinal tensile elastic modulus in the width direction.

20. The polyphenylene sulfide film roll according to claim 16, wherein the film thickness is 1 μm or more and 30 μm or less.

21. A metallized film roll having a metal layer provided on at least one side of the polyphenylene sulfide film roll according to any one of claims 16 to 20.

22. A current collecting foil roll having a metal layer laminated on the surface of the polyphenylene sulfide film roll according to any one of claims 16 to 20.

23. An electrode plate roll having an electrode material layer formed on the surface of the current collecting foil roll according to claim 22.

Citation Information

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