JP7272263B2 - polyarylene sulfide film - Google Patents

Description

TECHNICAL FIELD The present invention relates to a polyarylene sulfide film containing a polyarylene sulfide resin as a main component.

Polyarylene sulfide (hereinafter sometimes abbreviated as PPS) film has excellent properties as an engineering plastic, such as excellent heat resistance, electrical insulation, and moisture and heat resistance. It is widely used in electronic parts such as flexible printed circuit boards and insulating tapes, and automotive parts such as motor insulators. However, in recent years, as electronic devices have become smaller and larger in capacity, the amount of electric power handled has increased and heat generation has increased. ing.

Here, Patent Document 1 proposes a resin composition containing syndiotactic polystyrene containing magnesium hydroxide, glass fiber and PPS resin for the purpose of improving flame retardancy. Further, Patent Document 2 proposes a biaxially stretched PPS film in which the content of sodium metal element is reduced to a specific amount or less and the electrical insulation is improved by adding an antioxidant. For the purpose of controlling dimensional changes at low and high temperatures, Patent Documents 3 and 4 propose PPS resin compositions containing thermoplastic elastomers, polyetherimides, polysulfones and polyphenyl ethers. However, it has been difficult to achieve a PPS film that achieves both electrical insulation and a low coefficient of thermal expansion or a low coefficient of thermal shrinkage only by combining the above.

JP 2010-260963 A JP 2015-74725 A JP-A-2010-90368 JP 2014-55219 A

An object of the present invention is to provide a PPS film that can be suitably used for capacitors, insulating tapes, motor insulation, and circuit board applications and has both high electrical insulation and a low coefficient of thermal expansion or low coefficient of thermal shrinkage.

(1) Polyarylene sulfide-based resin (A) is the main component, and has a layer (P1 layer) containing a thermoplastic resin (B) different from the resin (A), and the thermoplastic resin (B) is the following The sum of the content WA1 of the polyarylene sulfide resin (A) of the P1 layer and the content WB1 of the thermoplastic resin (B) different from the resin (A), which has the chemical formula and has a sulfonyl group, is When the content WB1 of the thermoplastic resin (B) is 100 parts by weight, the content WB1 of the thermoplastic resin (B) is 0.1 parts by weight or more and less than 50 parts by weight, and the P1 layer contains the polyarylene sulfide resin (A) and the thermoplastic resin (B ) is present as a dispersed phase, and a biaxially stretched polyarylene sulfide film in which the ratio of the major axis to the minor axis of the dispersed diameters of the thermoplastic resin (B) is 1.05 or more.

(where R ₁ to R ₂ in the formula are each H, OH, methoxy group, ethoxy group, trifluoromethyl group, aliphatic group having 1 to 13 carbon atoms, or aromatic group having 6 to 10 carbon atoms is.)
(2) Thermal expansion coefficient (C) (ppm/°C), breakdown voltage (R) (kV) and thickness (t) (μm) according to (1) satisfying the following formulas (1) and ( 2 ) Biaxially oriented polyarylene sulfide film.

C<80 (1)
R>0.17×t+1.0 (2)
( 3 ) The difference (Tcc−Tg) between the lowest glass transition temperature (Tg) and the cold crystallization temperature (Tcc) measured in the 2nd run in differential scanning calorimetry (DSC) measurement is greater than 45° C. (1) or The biaxially stretched polyarylene sulfide film according to (2) .
( 4 ) The biaxially stretched polyarylene sulfide film according to any one of (1) to ( 3 ), which has a highest glass transition temperature of 200°C or higher as measured by DSC.
( 5 ) The biaxially stretched polyarylene according to any one of (1) to ( 4 ), which has a strength retention at break of 75% or more in at least one direction after standing in an oven at 200°C for 1000 hours. sulfide film.
( 6 ) The biaxially stretched polyarylene sulfide film according to any one of (1) to (5), wherein the highest tan δ peak temperature observed in dynamic viscoelasticity (DMA) measurement is 200°C or higher.
( 7 ⁾ Orientation ^{parameter (} Op= ^I (1093 cm ⁻¹ )/I (1385 cm ⁻¹ )), any of (1) to ( 6 ) where the orientation parameter in the longitudinal direction (OpM) and the orientation parameter in the width direction (OpT) satisfy the following formula The biaxially stretched polyarylene sulfide film according to .
(Op_M/Op_T) < 1.0 (3)
( 8 ) The biaxially stretched polyarylene sulfide film according to any one of (1) to ( 7 ), wherein the thermoplastic resin (B) has an average dispersed diameter of more than 0.5 μm.
( 9 ) The biaxially stretched polyarylene sulfide film according to any one of (1) to ( 8 ), which has a heat shrinkage rate of 5.0% or less in the longitudinal direction (conveyance direction) after heat treatment at 250°C for 10 minutes. .
( 10 ) The biaxially stretched polyarylene sulfide film according to any one of (1) to (9), which has a heat shrinkage rate of 1.0% or less in the longitudinal direction (conveyance direction) after heat treatment at 250°C for 10 minutes. .
( 11 ) The method for producing a biaxially stretched polyarylene sulfide film according to any one of (1) to ( 10 ), wherein the draw ratio in the width direction is higher than the draw ratio in the longitudinal direction.

According to the present invention, it is possible to provide a polyarylene sulfide film that achieves both high electrical insulation and a low coefficient of thermal expansion or low coefficient of thermal shrinkage. In particular, it can be suitably used for electronic parts such as dielectrics of capacitors, copper-clad laminates, flexible printed boards and insulating tapes, and automobile parts such as motor insulators.

Conceptual diagram of a thermoplastic resin (B) present as a spherical dispersed phase in a polyarylene sulfide resin (A) Conceptual diagram of a thermoplastic resin (B) present as a spindle-shaped dispersed phase in a polyarylene sulfide resin (A). Conceptual diagram in which the thermoplastic resin (B) exists as an amorphous dispersed phase in the polyarylene sulfide resin (A).

The polyarylene sulfide film of the present invention has a polyarylene sulfide-based resin (A) as a main component, has a layer (P1 layer) containing a thermoplastic resin (B) different from the resin (A), and has a thermoplastic resin (B) must have the following chemical formula .

(where R ₁ to R ₂ in the formula are each H, OH, methoxy group, ethoxy group, trifluoromethyl group, aliphatic group having 1 to 13 carbon atoms, or aromatic group having 6 to 10 carbon atoms is.)
The polyarylene sulfide resin (A) in the present invention is a homopolymer or copolymer containing --(Ar--S)-- as the main structural unit and preferably containing 80 mol % or more of the repeating unit. Ar is a group containing an aromatic ring in which a bond exists in an aromatic ring, and examples thereof include divalent repeating units represented by the following formulas (F) to (Q), etc. Among them, the formula ( Repeating units represented by F) are particularly preferred.

(wherein R1 and R2 in the formula are substituents selected from hydrogen, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms and a halogen group, and R1 and R2 may be the same or different; is also good.)
As long as this repeating unit is the main structural unit, it can contain a small amount of branching units or cross-linking units represented by the following formulas (R) to (U). The amount of copolymerization of these branching units or cross-linking units is preferably in the range of 0 to 5 mol%, more preferably in the range of 0 to 1 mol%, relative to 1 mol of —(Ar—S)— units. more preferred.

Moreover, the polyarylene sulfide resin (A) used in the film of the present invention may be a random copolymer, a block copolymer, or a mixture thereof having the repeating unit.

The melt viscosity of the polyarylene sulfide resin (A) in the film of the present invention is not particularly limited, but it is 100 to 2,000 Pa·s at a temperature of 310°C and a shear rate of 1,000 (1/sec). and more preferably 200 to 1,000 Pa·s.

Typical examples of these polyarylene sulfide resins (A) include polyphenylene sulfide, polyphenylene sulfide sulfone, polyphenylene sulfide ketone, random copolymers, block copolymers and mixtures thereof. A particularly preferred polyarylene sulfide-based resin (A) preferably contains 80 mol% or more, more preferably 85 mol%, and still more preferably p-phenylene sulfide units represented by the following formula (V) as the main structural unit of the polymer. A polyphenylene sulfide containing 90 mol % or more is mentioned. If the p-phenylene sulfide unit is less than 80 mol %, the polymer crystallinity, thermal transition temperature, etc. are low, and the heat resistance, dimensional stability, mechanical properties, etc. that are characteristics of the polyarylene sulfide resin (A) are impaired. There is

The method for producing the polyarylene sulfide-based resin (A) is not particularly limited. Including the step of treating with an aqueous solution is preferred for reducing the crystallization rate of the polyarylene sulfide. The polyarylene sulfide-based resin (A) containing a group having an aromatic ring other than a phenylene group can be obtained by using a monomer in which the phenylene group is replaced with an aromatic ring other than the phenylene group.

The polyarylene sulfide-based resin (A) used in the film of the present invention can be crosslinked/polymerized by heating in the air, under an atmosphere of an inert gas such as nitrogen, or under reduced pressure, as long as the properties of the present invention are not impaired. heat treatment, washing with organic solvents, hot water and acid aqueous solutions, activation with functional group-containing compounds such as acid anhydrides, amines, isocyanates and functional group disulfide compounds before use. is also possible.

The present invention is a film containing polyarylene sulfide as a main component. Here, the main component means that the polyarylene sulfide-based resin (A) accounts for 50 parts by mass or more when the entire resin composition is 100 parts by weight. The film may be an unstretched film, a uniaxially stretched film, or a biaxially stretched film, and is preferably a biaxially stretched film from the viewpoint of long-term heat resistance and productivity. As a method for obtaining a biaxially stretched film as a film, a sequential biaxial stretching method (a stretching method combining stretching in one direction at a time, such as a method of stretching in the longitudinal direction and then stretching in the width direction), and a simultaneous biaxial stretching method. (a method of stretching in the longitudinal direction and the width direction at the same time), or a method combining them can be used.

The thermoplastic resin (B) used in the polyarylene sulfide film of the present invention contains at least one structure of the following chemical formulas, more preferably chemical formulas (A), (B), (C) and (D) and more preferably chemical formulas (A) and (D). In particular, when it contains the chemical formula (A), it is preferable because it contributes to the reduction of the thermal expansion coefficient, the improvement of the electrical insulation, and the improvement of the film-forming property (especially stretchability), and this is a thermoplastic resin containing the chemical formula (A) It is assumed that (B) interacts with the PPS resin. If the thermoplastic resin (B) does not contain the structure of the following chemical formula, not only will it not be possible to obtain a sufficient coefficient of thermal expansion and electrical insulation, but when the resin kneaded with polyarylene sulfide is formed into a film and stretched, In addition, peeling may occur at the interface with the thermoplastic resin B, which may lead to breakage of the film, which is not preferable.

(where R ₁ to R ₆ in the formula are each H, OH, methoxy group, ethoxy group, trifluoromethyl group, aliphatic group having 1 to 13 carbon atoms, or aromatic group having 6 to 10 carbon atoms is.)
Examples of the thermoplastic resin (B) include various polymers such as polyamide, polyetherimide, polyethersulfone, polyphenylsulfone, polysulfone, polyphenylene ether, polyester, polyarylate, polyamideimide, polycarbonate, and polyetheretherketone. Blends containing at least one of these polymers can be used. From the viewpoint of heat resistance and electrical insulation, the thermoplastic resin (B) is more preferably a resin selected from polyphenylsulfone, polyethersulfone, polyphenylene ether, polysulfone, and polyetherimide, and more preferably polyphenylsulfone or Polyethersulfone is preferred.

In the present invention, the timing of mixing the polyarylene sulfide resin (A) and the thermoplastic resin (B) is not particularly limited. There is a method of preliminarily melt-kneading (pelletizing) the mixture to form master pellets, and a method of mixing and melt-kneading during melt extrusion. Among them, a method of forming master pellets using an apparatus such as a twin-screw extruder that is subjected to shear stress is preferable. In this case, in the kneading section, it is preferable to knead so that the resin temperature ranges from +5° C. to 80° C. of the melting point of the polyarylene sulfide-based resin (A), more preferably +10° C. to the melting point of the polyarylene sulfide-based resin (A). C. to 80.degree. C., more preferably the melting point of the polyarylene sulfide resin (A)+15.degree. C. to 70.degree. Also, the screw rotation speed is preferably in the range of 100 rpm to 500 rpm, more preferably in the range of 150 rpm to 400 rpm. The dispersed diameter of the dispersed phase can be controlled by setting the resin temperature and the screw rotation speed within preferable ranges. The ratio of (screw shaft length/screw shaft diameter) of the twin-screw extruder is preferably in the range of 20 or more and 60 or less, more preferably 30 or more and 50 or less.

The polyarylene sulfide film of the present invention has a coefficient of thermal expansion (C) (ppm/°C), a dielectric breakdown voltage (R) (kV) and a thickness (t) (μm) satisfying the following formulas (1) and (2). is preferred. More preferably, formulas (34) and (45) are satisfied, and more preferably formulas (56) and (67) are satisfied. If the coefficient of thermal expansion (C) is 80 or more, the film may be deformed during off-line processing steps involving heat treatment or when used in a high-temperature environment. Also, if the dielectric breakdown voltage (R) does not satisfy the relationship of the following formula, sufficient electrical insulation as a motor insulating material and electric/electronic parts may not be obtained.

C<80 (1)
R>0.17×t+1.0 (2)
C<78 (34)
R>0.17×t+1.2 (45)
C<77 (56)
R>0.17×t+1.5 (67)
Further, as a means for satisfying the following formulas for the coefficient of thermal expansion and the dielectric breakdown voltage, a biaxially stretched film containing a thermoplastic resin having any one of the structures described in the chemical formula (1) is used. The biaxially stretched film as used herein can be determined by whether or not the orientation parameter (Q) measured by a molecular orientation meter is 4300 or more. The orientation parameter (Q) is more preferably 4,500 or more, and still more preferably 4,700 or more. In the case of an unstretched film or a uniaxially stretched film, the degree of orientation of the molecular chains may not be sufficient, and the coefficient of thermal expansion and electrical insulation may not be satisfied. There is no particular upper limit for the value of the orientation parameter (Q), but 5500 or less is the substantial upper limit for a film that can be stably formed without breaking.

In the polyarylene sulfide film of the present invention, the P1 layer is preferably a layer in which the thermoplastic resin (B) exists as a dispersed phase in the polyarylene sulfide resin (A). The term "dispersed phase" as used herein refers to an island component having a sea-island structure composed of the polyarylene sulfide resin (A) and the thermoplastic resin (B). The shape of the thermoplastic resin (B) means that the thermoplastic resin (B) exists in the polyarylene sulfide film of the present invention in a circular, elliptical, spindle-shaped, irregular shape, or the like. The morphology can be confirmed by (TEM) observation, scanning electron microscope (SEM) observation, or the like.

In the polyarylene sulfide film of the present invention, the difference (Tcc-Tg1) between the lowest glass transition temperature (Tg1) measured in the 2nd run of differential scanning calorimetry (DSC) and the cold crystallization temperature (Tcc) is greater than 45°C. is preferred. More preferably above 48°C, still more preferably above 50°C. If (Tcc-Tg1) is 45° C. or less, crystallization may proceed excessively during the stretching step or heat treatment step, causing breakage or the like, which may hinder stable film formation. Note that (Tcc-Tg1) can be made larger than 45° C. by including a thermoplastic resin having any one of the structures described in chemical formula (1).

The cold crystallization temperature referred to here is, according to JIS K-7122 (1987), heating the resin from 25°C to 350°C at a heating rate of 20°C/min (1st Run ), held in that state for 5 minutes, then rapidly cooled to 25° C. or less, and again heated from 25° C. to 350° C. at a rate of 20° C./min (2nd run). Let the heat release peak temperature in the differential scanning calorimetry chart be the cold crystallization temperature.

The polyarylene sulfide film of the present invention preferably has the highest glass transition temperature (Tg2) measured by DSC of 200° C. or higher. More preferably, it is 210°C or higher, and still more preferably 220°C or higher. When Tg2 is lower than 200°C, the coefficient of thermal expansion of the resulting polyarylene sulfide film may become large, which is not preferable. Although the upper limit of Tg2 is not particularly set, if the extrusion temperature of the polyarylene sulfide resin (A) exceeds 340°C, the melt viscosity may become too high and melt film formation may not be possible. The upper limit is preferably 340°C or less.

The thermoplastic resin (B) contained in the polyarylene sulfide film of the invention preferably has a sulfonyl group. If it does not contain a sulfonyl group, it is not preferable because the heat resistance and mechanical properties may deteriorate.

In the polyarylene sulfide film of the present invention, the total of the content WA1 of the polyarylene sulfide resin (A) in the P1 layer and the content WB1 of the thermoplastic resin (B) different from the resin (A) is 100 parts by weight. In this case, the content WB1 of the thermoplastic resin (B) is preferably 0.1 parts by weight or more and less than 50 parts by weight. More preferably, the content WB1 of the thermoplastic resin (B) is 0.1 parts by weight or more and less than 30 parts by weight, and even more preferably, the content WB1 of the thermoplastic resin (B) is 0.1 parts by weight or more and 15 parts by weight. less than parts by weight. If the content of the thermoplastic resin (B) is 50 parts by mass or more, it is not preferable because frequent tears may occur during stretching, making it impossible to form a film stably. Moreover, if the content of the thermoplastic resin (B) is less than 0.1 part by weight, the thermal expansion coefficient may increase and the dielectric breakdown voltage may decrease, which is not preferable.

In the polyarylene sulfide film of the present invention, the polyarylene sulfide-based resin (A) may be the main component, and the layer (P1 layer) containing the thermoplastic resin (B) different from the resin (A) may be a single layer. A layer made of the resin (A) or a layer made of the resin (B) can be provided as the P2 layer on at least one side of the P1 layer. Furthermore, it is also possible to use a configuration in which a layer having a thermoplastic resin (B) ratio lower than that of the P1 layer is laminated as the P2 layer when the resin component of the P2 layer is 1,000. Furthermore, not only a three-layer configuration such as P2 layer/P1 layer/P2 layer or P1 layer/P2 layer/P1 layer, but also a configuration in which five or more layers of P1 layers and P2 layers are alternately laminated can be used. A laminated structure is preferable because it contributes to improvement in mechanical properties and film formability.

The polyarylene sulfide film of the present invention preferably has a Young's modulus of 2.0 GPa or more. It is more preferably 2.5 GPa or more, and still more preferably 3.0 GPa or more. If the Young's modulus is less than 2.0 GPa, not only is the stiffness of the film lowered and the handleability deteriorated, but the film may be deformed during processing, which is not preferable.

The polyarylene sulfide film of the present invention preferably has an elongation at break of 10% or more. It is more preferably 20% or more, still more preferably 30% or more, even more preferably 80% or more, and most preferably 100% or more. If the elongation at break is less than 10%, not only is the film brittle and the handleability is lowered, but also the film tends to tear during processing, which is undesirable. Here, considering the transport process during processing, it is preferable that the elongation at the judgment point in the longitudinal direction is higher than in the width direction, and this may be achieved by increasing the draw ratio in the width direction rather than the draw ratio in the longitudinal direction. . The elongation at break can be increased by applying a drawing process at a low draw ratio, and the elongation at break can be further increased by performing an offline heat treatment (annealing) on the film obtained by the biaxial drawing process. may be possible.

The polyarylene sulfide film in the present invention preferably has a strength retention at break of 75% or more after being heated in an oven at 200° C. for 1000 hours. It is more preferably 80% or more, still more preferably 85% or more. The strength retention at break here is a value represented by the following formula. If the strength retention at break is less than 75%, the heat resistance of the film is low, and when used for a long time in a high temperature environment, the film It is not preferable because there is a risk of breakage. The above range of strength retention at break can be achieved by including a thermoplastic resin (B) having any one of the structures described in chemical formula (1).
Strength retention at break (%) = (strength at break after heating)/(strength at break before heating) x 100
The polyarylene sulfide film in the present invention preferably has a peak temperature of 200° C. or higher for the highest tan δ observed when measured at a frequency of 1 Hz in dynamic viscoelasticity (DMA) measurement. More preferably, it is 210°C or higher, and still more preferably 215°C or higher. If the highest peak temperature of tan δ is lower than 200° C., the resulting polyarylene sulfide film may have a large coefficient of thermal expansion, which is not preferred. There is no particular upper limit to the peak temperature of tan δ, but if it exceeds 340° C., which is the extrusion temperature of the polyarylene sulfide resin (A), the melt viscosity may become too high and melt film formation may not be possible. The upper limit of tan δ is preferably 340°C or less.

In the polyarylene sulfide film of the present invention, the thermoplastic resin (B) present as a dispersed phase in the polyarylene sulfide resin (A) has a dispersion diameter ratio of 1.05 or more between the major axis and the minor axis. preferable. More preferably, it is 2.00 or more, still more preferably 3.50 or more, and most preferably 4.00 or more. If the ratio of the major axis to the minor axis is less than 1.05, peeling occurs at the interface between the polyarylene sulfide resin (A) and the thermoplastic resin (B) during film stretching, and tearing occurs or the resulting stretching This is not preferable because the elongation at break of the film may decrease. It is believed that the larger the ratio of the major axis to the minor axis, the stronger the interaction between the polyarylene sulfide resin (A) and the thermoplastic resin (B), which contributes to the improvement of electrical properties, thermal properties and dimensional stability. Therefore, although no particular upper limit is set, it is estimated that the ratio of the major axis to the minor axis is about 20.00 as the practical upper limit, based on the draw ratio.

The polyarylene sulfide film in the present invention has an orientation calculated from the ratio of the absorbance at 1093 cm ^-1 (I (1093 cm ^-1 )) and the absorbance at 1385 ^cm (I (1385 cm ^-1 )) measured by FT-IR. In the degree parameter (Op=I(1093 cm ⁻¹ )/I(1385 cm ⁻¹ )), it is preferable that the orientation degree parameter (OpM) in the longitudinal direction and the orientation degree parameter in the width direction (OpT) satisfy the following formula. More preferably, the following formula (8) is satisfied, more preferably the following formula (9) is satisfied, even more preferably the following formula (10) is satisfied, and even more preferably the following formula (11) is satisfied. If the orientation parameter is 1.0 or more, the heat shrinkage rate in the longitudinal direction increases, and wrinkles are generated in the film during the reflow process when used as a circuit board, which is not preferable. In addition, in order for the orientation parameter to satisfy the following formula (3), the polyarylene sulfide film of the present invention contains a thermoplastic resin (B) having any one of the structures described in chemical formula (1), can be achieved by biaxially stretching the stretch ratio in the width direction higher than the stretch ratio of , and thermally crystallizing the biaxially oriented film by heat treatment at a temperature of 200° C. or higher. Here, when OpM/OpT is greater than 1.00, it indicates that orientation in the longitudinal direction (conveyance direction, MD direction) is stronger than orientation in the width direction (TD direction), and OpM/OpT is 1.00. If it is less than 00, it indicates that the orientation in the width direction (TD direction) is stronger than the orientation in the longitudinal direction (MD direction).
(OpM/OpT) < 1.00 (3)
(OpM/OpT)<0.95 (8)
(OpM/OpT) < 0.92 (9)
(OpM/OpT) <0.90 (10)
(OpM/OpT)<0.85 (11)
In the polyarylene sulfide film of the present invention, the average dispersed diameter of the thermoplastic resin (B) is preferably larger than 0.5 µm. More preferably, the dispersed diameter is 0.8 μm or more, and still more preferably 1.0 μm or more. The average dispersion diameter as used herein means that the cross section of the film is observed by a transmission electron microscope (TEM), a scanning electron microscope (SEM), or the like to confirm the dispersion form, and if it is a new circular shape, the diameter of the circle is determined. In the case of a deformed dispersion form such as an ellipse or a spindle shape, the diameter of the circumscribed circle can be used as the dispersion diameter. The average dispersion diameter of more than 0.5 μm can be achieved by preparing master pellets composed only of polyarylene sulfide resin (A) and thermoplastic resin (B) and using them to form a film. be. There is a known technique for reducing the dispersion diameter by adding a compatibilizer having a terminal reactive group such as an epoxy group or an isocyanate group. It is not preferable because the durability may decrease.
The polyarylene sulfide film in the present invention preferably has a heat shrinkage rate of 5.0% or less in the longitudinal direction (conveyance direction, MD direction) after heat treatment at 250° C. for 10 minutes. It is more preferably 3.5% or less, still more preferably 2.5% or less, and even more preferably 1.0% or less. If the heat shrinkage is more than 5.0%, the film may wrinkle or curl in the reflow process when used as a circuit board, which is not preferable. In order to make the heat shrinkage rate 5% or less, the polyarylene sulfide film contains a thermoplastic resin (B) having one of the structures described in chemical formula (1), and the width is larger than the longitudinal draw ratio. It can be achieved by increasing the draw ratio in the direction, biaxially stretching, and heat-treating the biaxially oriented film at a temperature of 200° C. or higher for thermal crystallization. Furthermore, when the thermal shrinkage rate can be further reduced by heat-treating (annealing) the biaxially oriented polyarylene sulfide film obtained in an oven capable of raising the temperature to 220° C. or higher and transporting the film with a tension of 30 N or less. There is A temperature lower than 220°C is not preferable because sufficient heat treatment is not performed and the heat shrinkage rate at 250°C may not be sufficiently reduced. Further, if the conveying tension is greater than 30 N, excessive tension may be applied to the film during the heat treatment, and wrinkles may occur in the film surface, which is not preferable.

The polyarylene sulfide film of the present invention may contain other components, such as heat stabilizers (hindered phenol, hydroquinone, phosphite and substituted compounds thereof), weathering agents ( resorcinol-based, salicylate-based, benzotriazole-based, benzophenone-based, hindered amine-based, etc.), release agents and lubricants (montanic acid and its metal salts, its esters, its half-esters, stearyl alcohol, stearamide, various bisamides, bisurea and polyethylene wax, etc.), pigments (cadmium sulfide, phthalocyanine, carbon black for coloring, etc.), dyes (nigrosine, etc.), plasticizers (octyl p-oxybenzoate, N-butylbenzenesulfonamide, etc.), antistatic agents (alkyl sulfate type anionic antistatic agents, quaternary ammonium salt cationic antistatic agents, nonionic antistatic agents such as polyoxyethylene sorbitan monostearate, betaine amphoteric antistatic agents, etc.), flame retardants (e.g., red phosphorus , phosphate ester, melamine cyanurate, magnesium hydroxide, hydroxide such as aluminum hydroxide, ammonium polyphosphate, brominated polystyrene, brominated polyphenylene ether, brominated polycarbonate, brominated epoxy resin or these brominated flame retardants combination with antimony trioxide, etc.), other polymers (for example, amorphous resins such as polyamideimide, polyarylate, polyethersulfone, polyetherimide, polysulfone, polyphenylene ether, elastomers, etc.) can be added. .

EXAMPLES The present invention will be described more specifically with reference to examples below. Hereinafter, Examples 7-8 and Examples 15-17 shall be read as Reference Examples 7-8 and Reference Examples 15-17.

The methods for measuring physical properties and evaluating effects in the present invention were carried out according to the following methods.

(1) Thickness The thickness of the film was measured using a disk-shaped dial gauge thickness meter (manufactured by Mitutoyo Co., Ltd.) with a tip diameter of 4 mm, and the average value of five points was used as the thickness.

(2) Coefficient of Thermal Expansion The coefficient of thermal expansion was measured in accordance with JIS K7197-1991 while the temperature was raised to 250.degree. Let L0 be the initial sample length at 25° C. and 65 RH%, L1 be the sample length at temperature T1, and L2 be the sample length at temperature T2.

Note that T2=100 (° C.), T1=200 (° C.), and L0=20 mm.

Thermal expansion coefficient (ppm/°C) = (((L2-L1)/L0)/(T2-T1)) x 10 ⁶
Temperature increase/decrease rate: 5°C/min
Sample width: 4mm
Load: 29.4 mN.

(3) Cut the dielectric breakdown voltage film into a square of 25 cm × 25 cm, conditioned in a room at 23 ° C. and 65% Rh for 24 hours, and then, based on JIS C2151 (2006), an AC dielectric breakdown tester (Yamayo tester Using YST-243-50R manufactured by (manufactured by), the dielectric breakdown voltage (BDV) (kV) was measured at a frequency of 60 Hz and a boost rate of 1000 V/sec. In addition, when the formula (2) was satisfied, it was evaluated as “◯”, and when it was not satisfied, it was evaluated as “×”.

(4) Orientation (Q)
The film was cut into a 5 cm x 5 cm square and measured using a molecular orientation meter (MOA-7015, manufactured by Oji Scientific Instruments Co., Ltd.), and the average value of the minimum and maximum values of the degree of orientation (Q) was adopted as the value. .

(5) Confirmation of Dispersed Phase The film was cut parallel to the longitudinal direction and perpendicular to the film, and a cross-sectional sample was prepared by the frozen ultrathin section method. If the longitudinal direction cannot be determined, one of the directions is set to 0 °, and the direction is changed every 10 ° from -90 ° C to 90 ° C in the film plane, and the direction with the highest Young's modulus is the longitudinal direction. and In order to clarify the contrast of the dispersed phase, it may be stained with osmic acid, ruthenic acid, phosphotungstic acid, or the like. Using a transmission electron microscope (HT7700 manufactured by Hitachi), the cut surface was observed under the condition of an acceleration voltage of 100 kV, and a photograph was taken at a magnification of 2000 to confirm the shape of the dispersed phase. The obtained photograph is captured as an image in an image analyzer (Leica Application Suite LAS ver4.6 manufactured by Leica MICROSYSTEMS), 20 arbitrary dispersed phases are selected, the circumscribed circle of each dispersed phase is taken, and the average value of the diameter is calculated. and the size of the dispersed phase. Also, the major axis and minor axis of the dispersed phase were read and their ratio was calculated.

(6) Glass transition temperature (Tg), cold crystallization temperature (Tcc), melt crystallization temperature (Tmc)
According to JIS K-7121 (1987) and JIS K-7122 (1987), the film is measured by a differential scanning calorimeter "Robot DSC-RDC220" manufactured by Seiko Electronics Industry Co., Ltd., and for data analysis. Using the disk session "SSC/5200", measurements were made in the following manner.

(A) 1st Run measurement Weigh 5 mg of each film sample in a sample pan, heat the resin at a temperature increase rate of 20 ° C./min from 25 ° C. to 350 ° C. at a temperature increase rate of 20 ° C./min, and in that state It was held for 5 minutes and then rapidly cooled to 25°C or less.

(B) 2nd Run
Immediately after the 1st Run measurement was completed, the temperature was again raised from 25° C. to 350° C. at a rate of 20° C./min, and this state was maintained for 5 minutes before measurement. In the obtained 2ndRUN differential scanning calorimetry chart, the glass transition temperature (Tg) was obtained by determining the midpoint glass transition temperature based on the method described in JIS K-7121 (1987) (extended straight line of each baseline obtained from the point at which a straight line equidistant in the direction of the vertical axis intersects the curve of the stepwise change portion of the glass transition). When there were multiple glass transition temperatures, the above treatment was performed for all of them, and the lowest glass transition temperature was taken as Tg1, and the highest glass transition temperature was taken as Tg2.

(C) 3rd Run
Further, immediately after the 2nd Run measurement was completed, the temperature was lowered from 350°C to 25°C at a rate of 20°C/min, and the measurement was performed. In the differential scanning calorimetry chart obtained in the 3rd run, the peak top temperature of the crystallization peak was defined as the melt crystallization temperature (Tmc).

(7) Elongation at break/strength at break/Young's modulus The elongation at break of the film is based on ASTM-D882 (1997). A piece of 20 cm was cut out, and the tensile elongation at break and Young's modulus were measured at a chuck distance of 5 cm and a pulling speed of 300 mm/min. Each sample was measured five times, and the average value of the measurements was taken as the elongation at break, strength and Young's modulus. If the longitudinal direction cannot be determined, one of the directions is set to 0 °, and the direction is changed every 10 ° from -90 ° C to 90 ° C in the film plane, and the direction with the highest Young's modulus is the longitudinal direction. and the orthogonal direction thereof was the width direction (TD).

(8) Long-term heat resistance test In an oven (DRV420DA) manufactured by ADVANTEK set at 200°C, the film was sampled into strips of 1 cm x 20 cm in length and left for 1000 hours. Intensity was measured in the same manner as in (7). The retention rate of strength at break was calculated according to the following formula, and the average value in the MD and TD directions was taken as the retention rate of elongation at break.
Strength retention at break (%)=(strength at break after heating)/(strength at break before heating)×100.

(9) tan δ peak temperature Co., Ltd. Using DMS6100 manufactured by Hitachi High-Tech Science Co., Ltd., dynamic viscoelasticity measurement was performed under the following conditions, and the highest tan δ peak was read.
・Temperature increase rate: 2°C/min
・Starting temperature: 25°C
・End temperature: 240°C
・Retention time: 5 min
- Measurement frequency: 1 Hz.

(10) Orientation parameter measurement by FT-IR FT-IR was measured using an apparatus (Spectrometer Frontier, Microscope Spotlight 400, Stage Controller) manufactured by Perkin Elmer Co., Ltd. under the following conditions. Moreover, in the measurement, a wire-grid polarizing plate was inserted into the apparatus and measured. The sample was set so that the MD direction was 0° with respect to the stage X-axis (depth direction) direction, and the obtained values were used as the spectrum in the longitudinal direction (MD direction). The value obtained by rotating the film by 90° from the sample setting position in the MD direction measurement and setting the sample was used as the spectrum in the width direction (TD direction).
・Measurement mode: microscopic - ATR mode ・Measurement wavenumber: 750 to 4000 cm ^-1
・Number of accumulated times: 16 times ・Polarizing plate direction: 0°
From the spectrum obtained by the above measurement, using the absorbance at 1093 cm ^-1 (I (1093 cm ^-1 )) and the absorbance at 1385 cm ^-1 (I (1385 cm ^-1 )), the orientation parameter (Op) was calculated. The orientation parameter obtained from the spectrum in the MD direction was defined as OpM, and the orientation parameter obtained from the spectrum in the TD direction was defined as OpT.
Op=I (1093 cm ⁻¹ )/I (1385 cm ⁻¹ )
(11) Thermal Shrinkage Rate The film was sampled into strips of 10 mm×150 mm, the center 100 mm portion was marked, and the length between the marks was measured using a microscope (initial length: L0 (mm)). Then, the film was hung with a weight of 3 g and heat-treated for 10 minutes in a hot air oven heated to 250° C., and the length between marks was measured in the same manner as described above (length after heat treatment: L1 (mm)). The thermal shrinkage rate was calculated from the following formula using the obtained L0 and L1. Measurements were made in both the longitudinal (MD) direction and the width (TD) direction.
Thermal shrinkage rate (%) = (L0-L1)/L0 x 100.

(Reference Example 1) Preparation of polyarylene sulfide resin (A) In an autoclave, 9.44 kg (80 mol) of 47% sodium hydrosulfide, 3.43 kg (82.4 mol) of 96% sodium hydroxide, N-methyl- 13.0 kg (131 mol) of 2-pyrrolidone (NMP), 2.86 kg (34.9 mol) of sodium acetate, and 12 kg of ion-exchanged water were charged, and the temperature was gradually increased to 235°C over about 3 hours while passing nitrogen under normal pressure. After heating and distilling off 17.0 kg of water and 0.3 kg (3.23 mol) of NMP, the reaction vessel was cooled to 160°C. The amount of hydrogen sulfide scattered was 2 mol.

Next, 11.5 kg (78.4 mol) of p-dichlorobenzene (p-DCB) as a main monomer and 0.007 kg (0.04 mol) of 1,2,4-trichlorobenzene as a secondary component monomer are added, 22.2 kg (223 mol) of NMP was additionally added, the reaction vessel was sealed under nitrogen gas, and the temperature was raised from 200° C. to 270° C. at a rate of 0.6° C./min while stirring at 400 rpm. After 30 minutes at 270°C, 1.11 kg (61.6 mol) of water was injected into the system over 10 minutes, and the reaction was continued at 270°C for 100 minutes. After that, 1.60 kg (88.8 mol) of water was injected into the system again, cooled to 240°C, then cooled to 210°C at a rate of 0.4°C/min, and then rapidly cooled to near room temperature. The content was taken out, diluted with 32 liters of NMP, and the solvent and solids were separated by filtration through a sieve (80 mesh). The resulting particles were washed again with 38 liters of NMP at 85°C. After that, the particles were washed five times with 67 liters of warm water and filtered, and then washed five times with 70,000 g of a 0.05% by weight calcium acetate aqueous solution and filtered to obtain PPS polymer particles. This was dried with hot air at 60°C and then dried under reduced pressure at 120°C for 20 hours to obtain a white polyphenylene sulfide powder. The resulting polyphenylene sulfide resin had a glass transition temperature of 91°C, a melting point of 280°C, and a melt crystallization temperature of 188°C.

(Reference Example 2) Production of master pellets of polyarylene sulfide resin (A) and thermoplastic resin (B).
A co-rotating vented twin-screw kneading extruder provided with one kneading paddle kneading section was heated to 320 ° C., and 80 parts by mass of the polyarylene sulfide resin obtained in Reference Example 1 was added from the feed port, and polyphenyl Sulfone (PPSU: Solvay Advanced Polymers Co., Ltd., Radel R5800-NT) is supplied so as to be 20 parts by mass, melted and kneaded at a screw rotation speed of 200 rpm, discharged in a strand shape, and cooled with water at a temperature of 25 ° C. , and immediately cut to prepare master pellets containing 20 parts by mass of PPSU.

(Reference Example 3) Preparation of master pellets of polyarylene sulfide resin (A) and thermoplastic resin (B).
A co-rotating vented twin-screw kneading extruder provided with one kneading paddle kneading unit was heated to 320 ° C., and 80 parts by mass of the polyarylene sulfide resin obtained in Reference Example 1 was added from the feed port, polysulfone ( PSU: Solvay Advanced Polymers Co., Ltd., Udel P1700) was supplied so as to be 20 parts by mass, melt-kneaded at a screw rotation speed of 200 rpm, discharged in a strand shape, cooled with water at a temperature of 25 ° C., and immediately cut. Thus, a master pellet containing 20 parts by mass of PSU was produced.

(Reference Example 4) Preparation of master pellets of polyarylene sulfide resin (A) and thermoplastic resin (B).
A co-rotating vented twin-screw kneading extruder provided with one kneading paddle kneading section was heated to 320 ° C., and 80 parts by mass of the polyarylene sulfide resin obtained in Reference Example 1 was added from the feed port, and polyether Sulfone (PES: Solvay Advanced Polymers Co., Ltd., Veradel A201) was supplied so as to be 20 parts by mass, melted and kneaded at a screw rotation speed of 200 rpm, discharged in a strand shape, cooled with water at a temperature of 25 ° C., and immediately. By cutting, master pellets containing 20 parts by mass of PES were produced.

(Example 1)
95 parts by mass of the polyarylene sulfide-based resin obtained in Reference Example 1 and 5 parts by mass of the master pellets obtained in Reference Example 2 were dry-blended, and then vacuum-dried at 180° C. for 3 hours. Then, it was supplied to an extruder, melted at a temperature of 320° C. under a nitrogen atmosphere, and introduced into a T-die die. Then, it is extruded in the form of a sheet from the inside of the T-die to form a molten monolayer sheet, and the molten monolayer sheet is placed on a cast drum rotating at 3.0 m/min and kept at a surface temperature of 25°C. An unstretched film was obtained by casting while contact cooling and solidification by an electric application method. The obtained unstretched film was stretched in the longitudinal direction of the film at a stretching temperature of 102° C. at a stretching ratio of 3.3 times using a longitudinal stretching machine consisting of a group of heated rolls, utilizing the difference in peripheral speed of the rolls. . After that, both ends of the film were held by clips, and the film was led to a tenter and stretched at a stretching temperature of 100° C. in the width direction at a magnification of 3.4 times. Subsequently, after heat treatment at 280° C., relaxation treatment was performed by 5%, and after cooling to room temperature, film edges were removed to obtain a polyarylene sulfide film having a thickness of 29 μm. Table 1 shows the physical properties and characteristics of the obtained film.

(Examples 2-6)
Polyarylene was prepared in the same manner as in Example 1 except that the master pellets prepared in Reference Example 2 were added so that the amount of PPSU added was as shown in Table 1, and the stretching conditions were changed to the magnification shown in Table 1. A sulfide film was obtained. Table 1 shows the physical properties and characteristics of the obtained film.

(Examples 7-8)
The master pellets prepared in Reference Example 2 were added so that the amount of PPSU added was as shown in Table 1, dry-blended with the polyarylene sulfide resin obtained in Reference Example 1, and then vacuum-dried at 180°C for 3 hours. Then, it was supplied to an extruder, melted at a temperature of 320° C. under a nitrogen atmosphere, and introduced into a T-die die. Then, it is extruded into a sheet form from the inside of the T-die mouthpiece to form a molten monolayer sheet, and the molten monolayer sheet is placed on a cast drum rotating at 5.0 m/min and kept at a surface temperature of 25 ° C. An unstretched film was obtained by casting while contact cooling and solidification by an electric application method. Table 1 shows the physical properties and characteristics of the obtained film.

(Examples 9-12)
The polyarylene sulfide resin prepared in Reference Example 1 and the master pellets prepared in Reference Example 2 were added so that the amount of PPSU added was as shown in Table 1, and the stretching conditions were changed to those shown in Table 1. A polyarylene sulfide film was obtained in the same manner as in Example 1. Table 1 shows the physical properties and characteristics of the obtained film.

(Examples 13-14)
The polyarylene sulfide resin prepared in Reference Example 1 and the master pellets prepared in Reference Example 2 were added so that the amount of PPSU added was as shown in Table 1, and the stretching conditions were changed to those shown in Table 1. A polyarylene sulfide film was obtained in the same manner as in Example 1. Next, the obtained film was annealed for 2 minutes while conveying the film in an oven heated to 250° C. under a tension of 10 N. Table 1 shows the physical properties and characteristics of the obtained film.

(Example 15)
The polyarylene sulfide resin prepared in Reference Example 1 and the master pellets prepared in Reference Example 3 were added so that the amount of PSU added was as shown in Table 1, and the stretching conditions were changed to those shown in Table 1. A polyarylene sulfide film was obtained in the same manner as in Example 1. Table 1 shows the physical properties and characteristics of the obtained film.

(Example 16)
The film prepared in Example 15 was annealed under the same conditions as in Example 13 to obtain a polyarylene sulfide film. Table 1 shows the physical properties and characteristics of the obtained film.

(Example 17)
The polyarylene sulfide resin prepared in Reference Example 1 and the master pellets prepared in Reference Example 4 were added so that the amount of PES added was as shown in Table 1, and the stretching conditions were changed to the magnification shown in Table 1. A polyarylene sulfide film was obtained in the same manner as in Example 1. The resulting film was annealed under the same conditions as in Example 13 to obtain a polyarylene sulfide film. Table 1 shows the physical properties and characteristics of the obtained film.

(Comparative example 1)
100 parts by mass of the polyarylene sulfide resin obtained in Reference Example 1 was vacuum dried at 180° C. for 3 hours. Then, it was supplied to an extruder, melted at a temperature of 320° C. under a nitrogen atmosphere, and introduced into a T-die die. Then, it is extruded in the form of a sheet from the inside of the T-die to form a molten monolayer sheet, and the molten monolayer sheet is placed on a cast drum rotating at 3.0 m/min and kept at a surface temperature of 25°C. An unstretched film was obtained by casting while contact cooling and solidification by an electric application method. The obtained unstretched film was stretched in the longitudinal direction of the film at a stretching temperature of 102° C. at a stretching ratio of 3.3 times using a longitudinal stretching machine consisting of a group of heated rolls, utilizing the difference in peripheral speed of the rolls. . After that, both ends of the film were held by clips, and the film was led to a tenter and stretched at a stretching temperature of 100° C. in the width direction at a magnification of 3.4 times. Subsequently, after heat treatment at 280° C., relaxation treatment was performed by 5%, and after cooling to room temperature, film edges were removed to obtain a polyarylene sulfide film having a thickness of 28 μm. Table 1 shows the physical properties and characteristics of the obtained film.

1: polyarylene sulfide resin 2: thermoplastic resin (B)

Claims (11)

It has a polyarylene sulfide resin (A) as a main component and a layer (P1 layer) containing a thermoplastic resin (B) different from the resin (A), and the thermoplastic resin (B) has the following chemical formula: and a polyphenylsulfone having a sulfonyl group, the content WA1 of the polyarylene sulfide resin (A) of the P1 layer and the content WB1 of the thermoplastic resin (B) different from the resin (A) When the total is 100 parts by weight, the content WB1 of the thermoplastic resin (B) is 0.1 parts by weight or more and less than 50 parts by weight, and the P1 layer is a polyarylene sulfide resin (A) containing a thermoplastic resin A biaxially stretched polyarylene sulfide film, which is a layer in which (B) exists as a dispersed phase, and in which the ratio of the major axis to the minor axis of the dispersed diameters of the thermoplastic resin (B) is 1.05 or more.

(where R ₁ to R ₂ in the formula are each H, OH, methoxy group, ethoxy group, trifluoromethyl group, aliphatic group having 1 to 13 carbon atoms, or aromatic group having 6 to 10 carbon atoms is.) The biaxially stretched film according to claim 1, wherein the coefficient of thermal expansion (C) (ppm/°C), dielectric breakdown voltage (R) (kV) and thickness (t) (μm) satisfy the following formulas (1) and (2). Polyarylene sulfide film.
C<80 (1)
R>0.17×t+1.0 (2) 3. The difference (Tcc-Tg) between the lowest glass transition temperature (Tg) and the cold crystallization temperature (Tcc) measured in the 2nd run in differential scanning calorimetry (DSC) measurement is greater than 45° C. according to claim 1 or 2. biaxially oriented polyarylene sulfide film. The biaxially stretched polyarylene sulfide film according to any one of claims 1 to 3, which has a highest glass transition temperature of 200°C or higher as measured by DSC. The biaxially stretched polyarylene sulfide film according to any one of claims 1 to 4, which has a strength retention rate at break of 75% or more in at least one direction after standing in an oven at 200°C for 1000 hours. The biaxially stretched polyarylene sulfide film according to any one of claims 1 to 5, wherein the highest tan δ peak temperature observed in dynamic viscoelasticity (DMA) measurement is 200°C or higher. ^{The orientation} parameter (Op ⁼ I (1093 ^{cm - 1} )/I(1385 cm ⁻¹ )), the orientation parameter in the longitudinal direction (OpM) and the orientation parameter in the width direction (OpT) satisfy the following formulae: The biaxial structure according to any one of claims 1 to 6. Stretched polyarylene sulfide film.
(Op_M/Op_T) < 1.0 (3) The biaxially stretched polyarylene sulfide film according to any one of claims 1 to 7, wherein the thermoplastic resin (B) has an average dispersion diameter of more than 0.5 µm. The biaxially stretched polyarylene sulfide film according to any one of claims 1 to 8, which has a heat shrinkage rate of 5.0% or less in the longitudinal direction (conveyance direction) after heat treatment at 250°C for 10 minutes. The biaxially stretched polyarylene sulfide film according to any one of claims 1 to 9, which has a thermal shrinkage of 1.0% or less in the longitudinal direction (conveyance direction) after heat treatment at 250°C for 10 minutes. The method for producing a biaxially stretched polyarylene sulfide film according to any one of claims 1 to 10, wherein the draw ratio in the width direction is higher than the draw ratio in the longitudinal direction.

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