JP7268346B2 - Laminated polyphenylene sulfide films, film rolls and packaging materials - Google Patents

Description

TECHNICAL FIELD The present invention relates to a laminated polyphenylene sulfide film, and more particularly to a laminated polyphenylene sulfide film suitable for use in packaging materials that require chemical resistance, and a method for producing the same.

Biaxially oriented polyphenylene sulfide film has properties such as excellent heat resistance, flame retardancy, electrical insulation, low moisture absorption and chemical resistance. etc. has been suitably used.

In recent years, taking advantage of its high chemical resistance, it has been applied to packaging materials, and biaxially oriented polyphenylene sulfide film has excellent chemical resistance and heat resistance. Since the surface is inert, the adhesiveness is poor. Therefore, it is necessary to impart adhesiveness, especially heat-sealing property, to use it for applications such as packaging materials.

As a means for imparting heat-sealing properties to a biaxially oriented polyphenylene sulfide film, for example, a film in which a layer into which a copolymer unit other than a poly-p-phenylene sulfide unit is introduced is laminated (Patent Documents 1 and 2). ).

JP 2007-326362 A Japanese Unexamined Patent Application Publication No. 2011-213109

However, in both Patent Documents 1 and 2, since the surface roughness of the layer into which the copolymerized units are introduced is smooth, slipperiness is lost, and wrinkles occur during heat sealing. Further, in Patent Document 2, the curl of the two-layer laminated film is large, and there is a problem that the flatness of the heat-sealed film is deteriorated.

SUMMARY OF THE INVENTION An object of the present invention is to provide a laminated polyphenylene sulfide film excellent in chemical resistance, heat sealability and flatness, and a method for producing the same.

The present invention uses the following means in order to solve such problems.
(1). A laminate in which a polyphenylene sulfide layer (A layer) and a copolymerized polyphenylene sulfide layer (B layer) are directly laminated, the laminate is biaxially stretched, and differential scanning calorimetry (DSC) of the laminate is performed. ) has a first minute endothermic peak temperature (Ta) of 210° C. or more and less than 235° C. and a second minute endothermic peak temperature (Tb) of 240° C. or more and 260° C. or less in the 1st run of ). The corner lift at room temperature when placed in a room is 10 mm or less, the ratio of the thickness of the layer B to the total thickness of the laminated polyphenylene sulfide film is 1% or more and 20% or less, and the laminated polyphenylene sulfide film has a thickness of 3 A laminated polyphenylene sulfide film, wherein the layer B has a surface roughness (SRa) of 110 nm or more and 200 nm or less as determined by a dimensional surface roughness meter, and the layer A is made of a polyparaphenylene sulfide resin.
(2). The laminated polyphenylene sulfide film according to (1), wherein the total thickness of the laminated polyphenylene sulfide film is 16 μm or more and 100 μm or less.
( 3 ). (1) or (2), wherein the particle content of the layer B is 0.2% by weight or more and 1.0% by weight or less when the total weight of the layer B of the laminated polyphenylene sulfide film is 100% by weight. Laminated polyphenylene sulfide film.
( 4 ). The laminated polyphenylene sulfide film according to any one of (1) to (3), wherein the copolymerized polyphenylene sulfide of the laminated polyphenylene sulfide film is copolymerized with 6 mol% or more and 12 mol% or less of poly-m-phenylene sulfide units. .
( 5 ). A film roll obtained by winding the laminated polyphenylene sulfide film according to any one of (1) to ( 4 ).
( 6 ). A packaging material obtained by laminating a pair of the laminated polyphenylene sulfide films according to any one of (1) to ( 4 ) with a layer B interposed therebetween.

INDUSTRIAL APPLICABILITY According to the present invention, a laminated polyphenylene sulfide film excellent in heat-sealability and flatness can be obtained, and it can be suitably used in packaging materials that require chemical resistance.

The laminated polyphenylene sulfide film of the present invention has a structure in which a biaxially oriented polyphenylene sulfide film (A layer) and a biaxially oriented copolymerized polyphenylene sulfide film (B layer) are directly laminated.

The biaxially oriented polyphenylene sulfide film (layer A) used in the present invention is a film obtained by melt-molding a polyphenylene sulfide resin composition into a sheet, biaxially stretching, and heat-treating the sheet. Here, the polyphenylene sulfide resin composition refers to a polymer containing 85 mol% or more, preferably 90 mol% or more, more preferably 90 mol% or more of a poly-p-phenylene sulfide unit represented by the following chemical formula 1 as a main repeating unit of the polymer. contains 98 mol % or more of poly-p-phenylene sulfide units. If such a component is less than 85 mol %, the crystallinity, softening point, etc. of the polymer may be lowered, and heat resistance, dimensional stability, mechanical properties, etc. may be impaired.

The biaxially oriented copolymerized polyphenylene sulfide film (layer B) used in the present invention is a film obtained by melt-molding a copolymerized polyphenylene sulfide resin composition into a sheet, biaxially stretching, and heat-treating the sheet. Here, the copolymerized polyphenylene sulfide resin composition preferably comprises poly-p-phenylene sulfide units as the main component in 88 mol % or more and 94 mol % or less of the repeating units. If the main component is less than 88 mol %, the heat resistance of the film may be lowered, and if it exceeds 94 mol %, the heat sealability may not be sufficiently improved. Specific examples of structural units other than poly-p-phenylene sulfide units include biphenylene sulfide units, biphenylene ether sulfide units, biphenylene sulfone sulfide units, biphenylene carbonyl sulfide units, and naphthalene sulfide units. It is preferable that poly-m-phenylene sulfide units represented by are copolymerized. Further, the copolymerization amount of poly-m-phenylene sulfide units is preferably 6 mol % or more and 12 mol % or less. The mode of copolymerization of the main component and the copolymerization component of the copolymerized polyphenylene sulfide resin composition is not particularly limited, but it may be a block copolymer or a random copolymer.

It is desirable that the A layer and the B layer are respectively composed of poly-p-phenylene sulfide or poly-m-phenylene sulfide described above, but the total mass of each layer is In the range of less than 10% by mass, other components such as polymers and particles other than polyphenylene sulfide (inorganic, organic, lubricants, colorants, etc.), UV absorbers, additives such as compatibilizers can be included. Examples of polymers other than polyphenylene sulfide include various polymers such as polyamide, polyetherimide, polyethersulfone, polysulfone, polyphenylene ether, polyester, polyarylate, polyamideimide, polycarbonate, polyolefin, and polyetheretherketone, and polymers of these polymers. Blends containing at least one are included. Examples of inorganic particles include inorganic fillers such as silica, alumina, calcium carbonate, barium carbonate, barium titanate, barium sulfate, calcium silicate, magnesium oxide, titanium oxide and zinc oxide. Particles of organic polymer compounds (for example, crosslinked polystyrene, etc.) that do not melt at high temperatures can be used.

A method for laminating the A layer and the B layer is not particularly limited, but a method by co-extrusion is preferably used.

The polyphenylene sulfide films of the A layer and the B layer in the present invention are biaxially oriented films so that the main properties necessary for the function of the film, such as improved mechanical strength, improved thermal stability, and improved chemical resistance, are expressed. preferred because The term "biaxially oriented" as used herein refers to a pattern showing a biaxially oriented pattern in wide-angle X-ray diffraction. A biaxially oriented polyphenylene sulfide film is generally produced by stretching an unstretched polyphenylene sulfide sheet in the longitudinal direction and the width direction of the sheet by a factor of about 2.5 to 5.0, followed by heat treatment to complete crystal orientation. can be obtained by In addition, it is preferable that stretching in the longitudinal direction and the width direction be a so-called sequential biaxial stretching method in which the stretching is performed separately and sequentially.

The laminated polyphenylene sulfide film of the present invention must have a first slight endothermic peak temperature (Ta) of 210°C or higher and lower than 235°C in the 1st run of differential scanning calorimetry (DSC), preferably 220°C or higher and 235°C. °C. When Ta is less than 210°C, crystallization of the film may not progress and the flatness may be reduced. When Ta is 235°C or more, the copolymerized polyphenylene sulfide resin of layer B melts and the surface of layer B becomes smooth. , slipperiness is remarkably deteriorated.

The laminated polyphenylene sulfide film of the present invention must have a second slight endothermic peak temperature (Tb) of 240°C or higher and 260°C or lower in the 1st run of differential scanning calorimetry (DSC), preferably 250°C or higher and 260°C. ℃ or less. When Tb is less than 240°C, the durability of the film may deteriorate, and when Tb exceeds 260°C, the heat-sealability cannot be sufficiently improved.

A roll of the laminated polyphenylene sulfide film of the present invention is cut into a 10 cm square film, and when the film is placed on a horizontal table, it is necessary that the corner lift is 10 mm or less at room temperature. If the corner lift exceeds 10 mm, the heat-sealed and bag-making processed packaging material curls and the flatness deteriorates.

The total thickness of the laminated polyphenylene sulfide film of the present invention is preferably 16 μm or more and 100 μm or less, more preferably 25 μm or more and 75 μm or less, and still more preferably 25 μm or more and 50 μm or less. If the thickness is less than 16 μm, the film may not have sufficient stiffness, and if the thickness exceeds 100 μm, heat may be difficult to transfer during heat sealing, resulting in poor adhesion.

The ratio of the thickness of the B layer to the total thickness of the laminated polyphenylene sulfide film of the present invention is preferably 1% or more and 20% or less, more preferably 1% or more and 15% or less, and still more preferably 5% or more and 15% or less. be. If the B layer thickness ratio exceeds 20%, the curl of the laminated polyphenylene sulfide film may increase and the planarity may deteriorate.

The surface roughness (SRa) of layer B determined by a three-dimensional surface roughness meter of the laminated polyphenylene sulfide film of the present invention is preferably 100 nm or more and 200 nm or less, more preferably 100 nm or more and 150 nm or less. If the surface roughness is less than 100 nm, lubricity may deteriorate.

In the B layer of the laminated polyphenylene sulfide film of the present invention, the content of the above-described particles is preferably 0.2% by weight or more and 1.0% by weight or less, more preferably 0.2% by weight or more and 1.0% by weight or less when the total weight of the B layer is 100% by weight. is 0.3% by weight or more and 1.0% by weight or less. When the particle content is less than 0.2% by weight, the surface roughness of the B layer becomes smooth and the lubricity is lowered. is inhibited, resulting in insufficient heat-sealability.

The copolymerized polyphenylene sulfide of the layer B of the laminated polyphenylene sulfide film of the present invention preferably contains 6 mol% or more and 12 mol% or less of poly-m-phenylene sulfide units, more preferably 6 mol% or more. It is 10 mol % or less. High interfacial adhesiveness can be obtained by using 6 mol % or more of poly-m-phenylene sulfide units. By setting the copolymerization amount of the poly-m-phenylene sulfide unit to 6 mol % or more and 12 mol % or less, the aforementioned second minute endothermic peak temperature (Tb) can be obtained.

The laminated polyphenylene sulfide film of the present invention is preferably wound into a roll for ease of storage and transportation.

The laminated polyphenylene sulfide films of the present invention are laminated in pairs so that the B layers face each other, and are joined without an adhesive to form a bag for packaging material. It is preferably used. The heat-sealing method is not particularly limited, but hot pressing is preferred from the viewpoint of processability.

Next, the method for producing the laminated polyphenylene sulfide film of the present invention will be described in detail below with specific examples.

Examples of methods for producing a polyphenylene sulfide resin include the following methods. Sodium sulfide and p-dichlorobenzene are reacted at high temperature and high pressure in an amide-based polar solvent such as N-methyl-2-pyrrolidone (hereinafter sometimes abbreviated as NMP). If necessary, a copolymer component such as trihalobenzene can also be included. As polymerization degree modifiers, caustic potash, carboxylic acid alkali metal salts, etc. are added, and the polymerization reaction is carried out at a temperature of 230 to 280°C. After the polymerization, the polymer is cooled, and the polymer is made into an aqueous slurry and filtered through a filter to obtain a granular polymer. This is stirred in an aqueous solution of acetate or the like at a temperature of 30 to 100° C. for 10 to 60 minutes, washed several times with deionized water at a temperature of 30 to 80° C., and dried to obtain a PPS granular polymer. The obtained granular polymer is washed with NMP at an oxygen partial pressure of 10 Torr or less, preferably 5 Torr or less, and then washed several times with deionized water at a temperature of 30 to 80° C. to remove by-product salts, polymerization aids and Unreacted monomers and the like are separated. If necessary, inorganic or organic additives are added to the polymer obtained above to such an extent that the objects of the present invention are not hindered to obtain a PPS resin.

As a method for producing a copolymerized polyphenylene sulfide resin, in the method for producing a polyparaphenylene sulfide resin described above, a monomer that gives a phenylene sulfide unit such as m-dichlorobenzene is blended instead of p-dichlorobenzene, and the same polymerization reaction is performed. There is a way to do it. The same applies to the introduction of units other than phenylene sulfide units.

Next, the obtained resin is supplied to an extruder, preferably an extruder having one or more stages of vent holes, melt-kneaded at a temperature of 290 to 360° C., extruded from a suitable nozzle, and melt-molded into a gut shape. , may be cut to a length of about 2 to 10 mm and pelletized. The obtained resin is dried in a vacuum heating dryer under the conditions of a temperature of 100 to 180° C. and a time of about 1 to 5 hours.

When adding additives such as other resins and particles (inorganic, organic, lubricants or colorants), UV absorbers, and compatibilizers to the resin obtained, if necessary, the resin obtained by the above method It can be used as a resin composition by mixing together with a Henschel mixer or the like, extruding or melt-molding in the same manner as described above.

In the film-forming process described later, it is permissible to use a plurality of types of resin pellets. For example, it is an embodiment in which pellets to which particles are added and pellets to which no particles are added are used in combination.

In addition, in the present invention, inert particles can be added to each layer in order to improve the handleability and workability of the laminated polyphenylene sulfide film. Examples of inert particles referred to herein include inorganic fillers such as silica, alumina, calcium carbonate, barium carbonate, barium titanate, barium sulfate, calcium silicate, magnesium oxide, titanium oxide and zinc oxide, and inorganic fillers that do not melt at 300°C. Particles of organic polymer compounds (for example, crosslinked polystyrene, etc.) can be used. The inert particles may be added to the polyphenylene sulfide layer (A layer), but are preferably added to the copolymerized polyphenylene sulfide layer (B layer) from the viewpoint of heat sealability.

Next, a method for producing a laminated polyphenylene sulfide film in which the biaxially oriented polyphenylene sulfide film (layer A) and the biaxially oriented copolymerized polyphenylene sulfide film (layer B) of the present invention are directly laminated will be described.

The polyphenylene sulfide resin composition and the copolymerized polyphenylene sulfide resin composition are supplied to separate melt extruders and heated to the melting points of the individual raw materials or higher. The raw materials melted by heating are laminated in two layers in a molten state in a merging device provided between the melt extruder and the mouthpiece outlet, and are extruded from the slit-shaped mouthpiece outlet. The molten laminate is cooled on a cooling drum to below the glass transition point of the PPS resin to obtain a substantially amorphous two-layer laminated sheet. A well-known melt extrusion device can be applied, but a single-screw or twin-screw extruder is convenient and preferably used.

Next, the amorphous two-layer laminate sheet thus obtained is stretched by a conventionally known sequential biaxial stretching machine or simultaneous biaxial stretching machine in the range of the glass transition point to the cold crystallization temperature of the PPS resin. After biaxial stretching, heat treatment is performed at a temperature in the range of 212 to 237° C. to obtain a biaxially oriented two-layer laminated polyphenylene sulfide film.

Stretching is preferably carried out in the longitudinal direction at 90° C. to 120° C. in a range of 3.0 to 4.0 times. In the case of the present invention, the draw ratio is more preferably 3.0 to 3.6, more preferably 3.0 to 3.5. In the present invention, if the draw ratio is less than 3.0 times, a biaxially oriented laminated polyphenylene sulfide film having sufficient film flatness may not be obtained. heat sealability may not be obtained.

Then, the film is preferably stretched in the width direction at 90° C. to 120° C. by a factor of 2.8 to 4.0. More preferably 2.8 to 3.3 times, still more preferably 2.8 to 3.0 times. In the present invention, if the draw ratio is less than 2.8 times, a biaxially oriented film having sufficient film flatness may not be obtained, and if the draw ratio exceeds 4.0 times, the heat seal of the present invention may not be obtained. You may not get sexuality.

In the present invention, the area draw ratio is preferably 10 times or more and 13 times or less, more preferably 10 times or more and 12 times or less, still more preferably 10 times, in order to obtain the heat-sealing property and flatness of the present invention. 11 times or less. If the areal draw ratio is less than 10 times, a biaxially oriented film having sufficient film flatness may not be obtained, and if it exceeds 13 times, the heat-sealability may deteriorate.

The heat treatment temperature is preferably 212° C. or higher and 237° C. or lower, more preferably 220° C. or higher and 237° C. or lower, and still more preferably 230° C. or higher and 237° C. or lower. In the present invention, when the heat treatment temperature is less than 212°C, a biaxially oriented film having sufficient film flatness may not be obtained, and when the heat treatment temperature exceeds 237°C, the easy lubricity of the B layer cannot be obtained. sometimes not. By performing heat treatment under this temperature condition, the above-mentioned first minute endothermic peak temperature (Ta) is obtained, so that sufficient slipperiness can be maintained, and even with the above-mentioned B layer thickness ratio, a sufficient flat surface You can get sex.

Furthermore, by performing a limited shrinkage treatment (relaxation) in the range of 1 to 20% in each of the longitudinal direction and/or the width direction, the relaxation of the orientation of the copolymerized polyphenylene sulfide layer can be promoted and the heat sealability can be improved, which is preferable. . More preferably 3 to 15%, still more preferably 3 to 10%.

A preferred embodiment of the present invention includes subjecting the copolymerized polyphenylene sulfide layer to corona discharge treatment or plasma treatment in order to impart stronger heat-sealing properties to the laminated polyphenylene sulfide film used in the present invention. Further, in the present invention, other sheet layers can be laminated as necessary as long as the effects of the present invention are not hindered.

The resulting biaxially oriented laminated polyphenylene sulfide film is then wound into a roll. The winding length is preferably 50 m or more and 3000 m or less.

Then, the biaxially oriented laminated polyphenylene sulfide films are paired and joined together so that the B layers face each other. As a joining method, a heat fusion method is convenient. As a method of thermal fusion bonding, for example, a method of thermal fusion bonding (thermocompression bonding) using a hot press is preferable.

[Measurement method of physical properties]
In the following, Example 5 shall be read as Reference Example 5. Hereinafter, the configuration and effects of the present invention will be described more specifically with reference to examples. In addition, the present invention is not limited to the following examples. Before describing each example, methods for measuring various physical properties will be described.

(1) First slight endothermic peak temperature (Ta)
The laminated polyphenylene sulfide film was measured in the range of 30° C. to 300° C. with a differential scanning calorimeter DSC Q100 (manufactured by TA Instruments) at a heating rate of 20° C./min. A peak temperature appearing at 210° C. or more and less than 235° C. in the 1st run of the differential scanning calorimetry chart obtained by this measurement was taken as the first slight endothermic peak temperature Ta. Note that when a plurality of peaks are observed in the range of 210° C. or more and less than 235° C., the average is taken as Ta.

(2) Second slight endothermic peak temperature (Tb)
The laminated polyphenylene sulfide film was measured in the range of 30° C. to 300° C. with a differential scanning calorimeter DSC Q100 (manufactured by TA Instruments) at a heating rate of 20° C./min. A peak temperature appearing at 240° C. or more and 260° C. or less in the 1st run of the differential scanning calorimetry chart obtained by this measurement was taken as the second slight endothermic peak temperature Tb. In addition, when a plurality of peaks are observed in the range of 240° C. or more and 260° C. or less, the average is taken as Tb.

(3) Curl amount (flatness)
The laminated polyphenylene sulfide film unwound from the roll is cut into 10 cm square samples from three locations, the center and both ends, and the lift of the corners when placed on a horizontal table at room temperature of 23° C. is measured. This was repeated 5 times, and the average value of the obtained corner lift was taken as the amount of curl in flatness evaluation.

(4) Thickness of laminated polyphenylene sulfide film A cross-section of a laminated polyphenylene sulfide film cut out with a microtome is observed with an optical microscope (100x) or a scanning electron microscope (1000x) and photographed. The total thickness of the laminate and the thickness of each layer were actually measured. The same measurement was performed at arbitrary five points of the laminate, and the average value was taken as the total thickness of the laminate and the thickness of each layer.

(5) Ratio of B layer thickness in laminated polyphenylene sulfide film From the thickness measured in (4), the ratio of B layer thickness was obtained from the following formula (A).
B layer thickness ratio (%)=((B layer thickness)/(total thickness))×100 Formula (A).

(6) Surface roughness (SRa) of laminated polyphenylene sulfide film
The B layer surface of the laminated polyphenylene sulfide film was measured by the stylus method under the following conditions using a three-dimensional surface roughness meter ET4000AK (manufactured by Kosaka Laboratory Ltd.). The surface roughness (SRa) is the mean value of the absolute values of the difference between the height of the roughness curved surface and the height of the central plane of the roughness curved surface.
Needle diameter 2μmR
Needle pressure 10mg
Measurement length 500μm
Longitudinal magnification 20000 times CUT OFF 250 μm
Measurement speed 100 μm/s
Measurement interval 5 μm
Number of records 80 lines Hysteresis width ±6.25 nm
Reference area 0.1 mm ² .

(7) Adhesiveness of Bag A bag-shaped sample was prepared by arranging laminated polyphenylene sulfide films cut into a size of 70 mm wide and 210 mm long so that the B layers face each other. One short side and two long sides of the sample are heat-sealed by a heat press at 270° C. and 5 kg/cm at 5 mm. After that, a double-sided tape is attached to the obtained bag-shaped sample over the entire length, the non-adhesive paper of the double-sided tape is peeled off, and the bag-shaped sample is fixed on a desk. A force gauge DS2-200N (manufactured by Imada Co., Ltd.) is set in the opening of the bag-shaped sample to which the double-sided tape is not attached, and the portion where the force gauge is set is pulled in a direction that bends 180° from the bag-shaped sample. This was repeated 5 times, and the average value of the obtained 180° peel strength was taken as the adhesiveness of the bag and evaluated according to the following criteria. S is very good, A is good, B is within the practical range, S, A, and B are acceptable, and C is unacceptable.
S: 180° peel strength of 25 N/15 mm or more A: 180° peel strength of 15 N/15 mm or more and less than 25 N/15 mm B: 180° peel strength of 5 N/15 mm or more and less than 15 N/15 mm C: 180° peel strength of 5 N/ Less than 15mm.

(8) Appearance of bag (wrinkles)
Laminated polyphenylene sulfide films cut into a size of 70 mm in width and 210 mm in length were arranged so that the B layers faced each other to prepare a bag-like sample. One short side and two long sides of the sample are heat-sealed by a heat press at 270° C. and 5 kg/cm at 5 mm. After that, the number of wrinkles of 5 mm or more generated on the surface of the sample was visually confirmed, and the appearance of the bag was evaluated according to the following criteria. S is very good, A is good, B is within the practical range, S, A, and B are acceptable, and C is unacceptable.
S: The number of wrinkles is 0 A: The number of wrinkles is 1 B: The number of wrinkles is 2 C: The number of wrinkles is 3 or more.

(9) Bag flatness (amount of curl)
Laminated polyphenylene sulfide films cut into a size of 70 mm in width and 210 mm in length were arranged so that the B layers faced each other to prepare a bag-like sample. One short side and two long sides of the sample are heat-sealed by a heat press at 270° C. and 5 kg/cm at 5 mm. After that, when the sample was placed on a horizontal table, the lifting of the corners was measured at room temperature, and the average value was used as the amount of curl in evaluating the flatness of the bag, and was evaluated according to the following criteria. S is very good, A is good, B is within the practical range, S, A, and B are acceptable, and C is unacceptable.
S: Curling amount is 0 mm
A: The curl amount is more than 0 mm and 5 mm or less B: The curl amount is more than 5 mm and 10 mm or less C: The curl amount is more than 10 mm.

[Reference Example 1] Preparation of polyphenylene sulfide resin pellet 1 An autoclave was charged with 100 mol parts of sodium sulfide nonahydrate, 45 mol parts of sodium acetate and 259 mol parts of N-methyl-2-pyrrolidone, and gradually stirred. The temperature was raised to 220° C. and the contained water was removed by distillation. After dehydration, 101 mol of p-dichlorobenzene as a main monomer and 0.2 mol of 1,2,4-trichlorobenzene as a secondary component were added together with 52 mol of NMP and heated to 170°C. After filling with nitrogen at a pressure of 3 kg/cm 2 at a temperature of , the temperature was raised and polymerization was carried out at a temperature of 260° C. for 4 hours. After the polymerization was completed, the mixture was cooled, the polymer was precipitated in distilled water, and a small mass of polymer was collected using a wire mesh having 150 mesh openings. The nodular polymer thus obtained was washed five times with distilled water at 90°C and then dried at a temperature of 120°C under reduced pressure to obtain a resin having a melting point of 280°C and a glass transition temperature of 91°C. rice field. Next, 0.7% by weight of calcium carbonate powder having a volume average particle size of 1.0 μm is added to the resin, uniformly dispersed and blended, extruded into a gut shape by a 30 mmφ twin-screw extruder at a temperature of 320° C., polyparaphenylene. A sulfide resin composition 1 was obtained.

[Reference Example 2] Preparation of copolymerized polyphenylene sulfide resin pellet 1 A copolymerized polyphenylene sulfide resin composition 1 was produced in the same manner as in the production of the polyphenylene sulfide resin composition 1 of Reference Example 1, except that ,4-trichlorobenzene was used. The melting point of the resin composition was 250°C.

[Reference Example 3] Preparation of copolymerized polyphenylene sulfide resin pellet 2 A copolymerized polyphenylene sulfide resin composition 2 was produced in the same manner as in the production of the polyphenylene sulfide resin composition 1 of Reference Example 1, except that ,4-trichlorobenzene was used. The melting point of the resin composition was 260°C.

[Reference Example 4] Preparation of copolymerized polyphenylene sulfide resin pellets 3 A copolymerized polyphenylene sulfide resin composition 3 was produced in the same manner as in the production of the polyphenylene sulfide resin composition 1 of Reference Example 1, except that ,4-trichlorobenzene was used. The melting point of the resin composition was 240°C.

[Reference Example 5] Preparation of copolymerized polyphenylene sulfide resin pellets 4 A copolymerized polyphenylene sulfide resin composition 4 was produced in the same manner as in the production. The melting point of the resin composition was 250°C.

[Reference Example 6] Preparation of Copolymerized Polyphenylene Sulfide Resin Pellets 5 A copolymerized polyphenylene sulfide resin composition 5 was produced in the same manner as in the production. The melting point of the resin composition was 250°C.

[Reference Example 7] Preparation of copolymerized polyphenylene sulfide resin pellets 6 A copolymerized polyphenylene sulfide resin composition 6 was produced in the same manner as in the production. The melting point of the resin composition was 250°C.

[Reference Example 8] Preparation of copolymerized polyphenylene sulfide resin pellets 7 A copolymerized polyphenylene sulfide resin composition 7 was produced in the same manner as in the production of the polyphenylene sulfide resin composition 1 of Reference Example 1, except that ,4-trichlorobenzene was used. The melting point of the resin composition was 265°C.

[Reference Example 9] Preparation of copolymerized polyphenylene sulfide resin pellets 8 86 mol parts of p-dichlorobenzene as main component monomer, 15 mol parts of m-dichlorobenzene as secondary component monomers, and 0.2 parts mol of 1,2 A copolymerized polyphenylene sulfide resin composition 8 was produced in the same manner as in the production of the polyphenylene sulfide resin composition 1 of Reference Example 1, except that ,4-trichlorobenzene was used. The melting point of the resin composition was 225°C.

[Example 1] Production of biaxially oriented laminated polyphenylene sulfide film 1 Each was dried at a temperature of 180° C. for 4 hours under a reduced pressure of 3 mmHg using a vacuum dryer. A dried polyparaphenylene sulfide resin composition 1 was supplied to a single-screw extruder and melted at 310°C. Also, the dried copolymerized polyphenylene sulfide resin composition 1 was supplied to another vented twin-screw kneading extruder and melted at 280°C. After filtering the two melted resin compositions with a stainless steel fiber sintered filter with an average opening of 8 μm, they were combined with a two-layer confluence block equipped with a rectangular composite part, and passed through a T die with a width of 940 mm and a lip gap of 3 mm. The composition was extruded from a die such that the ratio of the amount of polyparaphenylene sulfide resin composition 1:copolymerized polyphenylene sulfide resin composition 1=84:16, and extruded into a sheet. Next, this sheet was wound around a casting drum having a surface temperature of 25° C. by an electrostatic casting method and solidified by cooling to prepare an unstretched two-layer laminated film having a thickness of about 480 μm.

Using sequential biaxial stretching, the obtained unstretched film is run in contact with a plurality of heating rolls having a surface temperature of 92°C, and is longitudinally stretched between cooling rolls having different peripheral speeds of 25°C and provided next to the heating rolls. It was stretched 3.7 times in the direction. The uniaxially stretched sheet thus obtained was stretched by a factor of 3.4 at a temperature of 100°C in the direction perpendicular to the longitudinal direction using a tenter, followed by stretching at a temperature of 200°C for 10 seconds, followed by stretching at a temperature of 235°C. After heat treatment for 10 seconds, the film was subjected to a limited shrinkage treatment of 4.5% for 10 seconds at a temperature of 230 ° C. in the direction perpendicular to the longitudinal direction of the film, intermediately cooled at a temperature of 115 ° C. for 9 seconds, and then cooled to room temperature. A film having a thickness of 32 μm for layer A made of paraphenylene sulfide resin composition 1 and a thickness of B layer made of copolymerized polyphenylene sulfide resin composition 1 of 6 μm for a total thickness of 38 μm was obtained. The resulting film had a Ta of 233° C., a Tb of 250° C., and a curl amount of 4 mm.

[Example 2] Production of biaxially oriented laminated polyphenylene sulfide film 2 A film was obtained in the same manner as the biaxially oriented laminated polyphenylene sulfide film 1 except that the copolymerized polyphenylene sulfide resin composition 2 was used as the resin composition of the B layer. rice field. The resulting film had a Ta of 233° C., a Tb of 260° C., and a curl amount of 2 mm.

[Example 3] Production of biaxially oriented laminated polyphenylene sulfide film 3 A film was obtained in the same manner as the biaxially oriented laminated polyphenylene sulfide film 1 except that the copolymerized polyphenylene sulfide resin composition 3 was used as the resin composition of the B layer. rice field. The resulting film had a Ta of 233° C., a Tb of 240° C., and a curl amount of 5 mm.

[Example 4] Production of biaxially oriented laminated polyphenylene sulfide film 4 A film was obtained in the same manner as the biaxially oriented laminated polyphenylene sulfide film 1 except that the copolymerized polyphenylene sulfide resin composition 4 was used as the resin composition of the B layer. rice field. The resulting film had a Ta of 233° C., a Tb of 250° C., and a curl amount of 4 mm.

[Example 5] Production of biaxially oriented laminated polyphenylene sulfide film 5 A film was obtained in the same manner as the biaxially oriented laminated polyphenylene sulfide film 1 except that the copolymerized polyphenylene sulfide resin composition 5 was used as the resin composition of the B layer. rice field. The resulting film had a Ta of 233° C., a Tb of 250° C., and a curl amount of 4 mm.

[Example 6] Production of biaxially oriented laminated polyphenylene sulfide film 6 A film was obtained in the same manner as the biaxially oriented laminated polyphenylene sulfide film 1 except that the copolymerized polyphenylene sulfide resin composition 6 was used as the resin composition of the B layer. rice field. The resulting film had a Ta of 233° C., a Tb of 250° C., and a curl amount of 4 mm.

[Example 7] Production of biaxially oriented laminated polyphenylene sulfide film 7 A film was obtained in the same manner as the biaxially oriented laminated polyphenylene sulfide film 1 except that the thickness of layer A was 14 µm, the thickness of layer B was 2 µm, and the total thickness was 16 µm. . The resulting film had a Ta of 233° C., a Tb of 250° C., and a curl amount of 5 mm.

[Example 8] Production of biaxially oriented laminated polyphenylene sulfide film 8 A film was obtained in the same manner as the biaxially oriented laminated polyphenylene sulfide film 1 except that the thickness of the A layer was 84 m, the thickness of the B layer was 16 µm, and the total thickness was 100 µm. . The resulting film had a Ta of 233° C., a Tb of 250° C., and a curl amount of 2 mm.

[Example 9] Production of biaxially oriented laminated polyphenylene sulfide film 9 A film was obtained in the same manner as the axially oriented laminated polyphenylene sulfide film 1. The resulting film had a Ta of 233° C., a Tb of 250° C., and a curl amount of 0 mm.

[Example 10] Production of biaxially oriented laminated polyphenylene sulfide film 10 A film was obtained in the same manner as the axially oriented laminated polyphenylene sulfide film 1. The resulting film had a Ta of 233° C., a Tb of 250° C., and a curl amount of 8 mm.

[Example 11] Production of biaxially oriented laminated polyphenylene sulfide film 11 Except that the heat treatment after biaxial stretching was 220°C for 10 seconds and the limited shrinkage treatment was 215°C for 10 seconds, biaxially oriented laminated polyphenylene A film was obtained in the same manner as the sulfide film 1. The resulting film had a Ta of 217° C., a Tb of 250° C., and a curl amount of 9 mm.

[Example 12] Production of biaxially oriented laminated polyphenylene sulfide film 12 Except that the heat treatment after biaxial stretching was 237°C for 10 seconds and the limited shrinkage treatment was 232°C for 10 seconds, biaxially oriented laminated polyphenylene A film was obtained in the same manner as the sulfide film 1. The resulting film had a Ta of 234° C., a Tb of 250° C., and a curl amount of 6 mm.

[Example 13] Production of biaxially oriented laminated polyphenylene sulfide film 13 The thickness ratio is A layer: B layer = 80:20, the thickness of the A layer is 30.4 µm, the thickness of the B layer is 7.6 µm, and the total thickness is 38 µm. A film was obtained in the same manner as the biaxially oriented laminated polyphenylene sulfide film 1, except that the film was obtained. The resulting film had a Ta of 233° C., a Tb of 250° C., and a curl amount of 10 mm.

[Comparative Example 1] Production of biaxially oriented laminated polyphenylene sulfide film 13 A film was obtained in the same manner as for the biaxially oriented laminated polyphenylene sulfide film 1 except that the copolymerized polyphenylene sulfide resin composition 7 was used as the resin composition of the layer B. rice field. The resulting film had a Ta of 233° C., a Tb of 265° C., and a curl amount of 0 mm.

[Comparative Example 2] Production of biaxially oriented laminated polyphenylene sulfide film 14 A film was obtained in the same manner as the biaxially oriented laminated polyphenylene sulfide film 1 except that the copolymerized polyphenylene sulfide resin composition 8 was used as the resin composition of the layer B. rice field. The resulting film had a Ta of 233° C., a Tb of 225° C., and a curl amount of 10 mm.

[Comparative Example 3] Production of biaxially oriented laminated polyphenylene sulfide film 15 A film was obtained in the same manner as the axially oriented laminated polyphenylene sulfide film 1. The resulting film had a Ta of 233° C., a Tb of 250° C., and a curl amount of 20 mm.

[Comparative Example 4] Production of biaxially oriented laminated polyphenylene sulfide film 16 The biaxially oriented laminated polyphenylene was obtained except that the heat treatment after the biaxial stretching was performed at a temperature of 210°C for 10 seconds and the limited shrinkage treatment was performed at a temperature of 205°C for 10 seconds. A film was obtained in the same manner as the sulfide film 1. The resulting film had a Ta of 206° C., a Tb of 250° C., and a curl amount of 13 mm.

[Comparative Example 5] Production of biaxially oriented laminated polyphenylene sulfide film 17 The biaxially oriented laminated polyphenylene was obtained except that the heat treatment after the biaxial stretching was performed at a temperature of 245°C for 10 seconds and the limited shrinkage treatment was performed at a temperature of 240°C for 10 seconds. A film was obtained in the same manner as the sulfide film 1. The resulting film had a Ta of 240° C., a Tb of 250° C., and a curl amount of 11 mm.

[Summary of results]
In the 1st run of differential scanning calorimetry (DSC) of the laminated polyphenylene sulfide film, the first minute endothermic peak temperature (Ta) of 210 ° C. or higher and less than 235 ° C. and the second minute endothermic peak temperature (Tb) of 240 ° C. or higher and 260 ° C. or lower were measured. The curl amount is 10 mm or less, the total thickness is 16 μm or more and 100 μm or less, the ratio of the thickness of the B layer to the total thickness is 1% or more and 20% or less, and the surface roughness (SRa) of the B layer is 100 nm or more and 200 nm or less. In this case, the adhesion, appearance and flatness of the heat-sealed portion during bag making can be improved without impairing the chemical resistance. As a method for producing a laminated polyphenylene sulfide film in which chemical resistance, adhesion, appearance, and flatness can be achieved at the same time, the poly-m-phenylene sulfide unit of the copolymerized polyphenylene sulfide constituting the B layer is 6 mol% or more. By making it 12 mol% or less, both chemical resistance and adhesion are achieved, and when the thickness ratio of the B layer to the total thickness is 1% or more and 20% or less, the heat treatment temperature after biaxial stretching is 212 ° C. or more and 237 ° C. By doing the following, it became possible to suppress wrinkles and curls, and this was achieved stably.

Examples 2 to 12 in which the poly-m-phenylene sulfide unit of the copolymerized polyphenylene sulfide of the B layer, the particle content of the B layer, the total thickness, the thickness ratio of the B layer, and the heat treatment temperature are changed within the possible range are also sufficient. characteristics could be obtained.

On the other hand, in Comparative Example 1 in which the poly-m-phenylene sulfide unit of the copolymerized polyphenylene sulfide of the B layer is less than 6 mol%, the second minute endothermic peak temperature is high and the adhesion is insufficient. In No. 2, the copolymerized polyphenylene sulfide was melted by the heat treatment, the slipperiness of the B layer was deteriorated, and many wrinkles occurred during heat sealing. In Comparative Example 3, in which the thickness ratio of the layer B exceeds 20%, the curl of the laminated polyphenylene sulfide film was large, and the flatness was deteriorated even after bag making. In Comparative Example 4, where Ta is less than 210°C, the flatness of the laminated polyphenylene sulfide film is poor, and in Comparative Example 5, where Ta is 235°C or higher, the copolymerized polyphenylene sulfide melts and the slidability of the layer B remarkably deteriorates.

INDUSTRIAL APPLICABILITY According to the laminated polyphenylene sulfide film and the method for producing the same according to the present invention, it is possible to obtain a laminated polyphenylene sulfide film excellent in heat sealability and flatness suitable for use in packaging materials that require chemical resistance.

Claims (6)

A laminate in which a polyphenylene sulfide layer (A layer) and a copolymerized polyphenylene sulfide layer (B layer) are directly laminated, the laminate is biaxially stretched, and differential scanning calorimetry (DSC) of the laminate is performed. ) has a first minute endothermic peak temperature (Ta) of 210° C. or more and less than 235° C. and a second minute endothermic peak temperature (Tb) of 240° C. or more and 260° C. or less in the 1st run of ). The corner lift at room temperature when placed in a room is 10 mm or less , the ratio of the thickness of the B layer to the total thickness of the laminated polyphenylene sulfide film is 1% or more and 20% or less, and the laminated polyphenylene sulfide film is three-dimensional A laminated polyphenylene sulfide film, wherein the layer B has a surface roughness (SRa) of 110 nm or more and 200 nm or less as determined by a surface roughness meter, and the layer A is made of a polyparaphenylene sulfide resin. 2. The laminated polyphenylene sulfide film according to claim 1, wherein the thickness of the entire laminated polyphenylene sulfide film is 16 μm or more and 100 μm or less. 3. The laminated polyphenylene according to claim 1 or 2, wherein the particle content of the layer B is 0.2% by weight or more and 1.0% by weight or less when the total weight of the layer B of the laminated polyphenylene sulfide film is 100% by weight. sulfide film. The laminated polyphenylene sulfide film according to any one of claims 1 to 3, wherein the copolymerized polyphenylene sulfide of the laminated polyphenylene sulfide film is copolymerized with 6 mol% or more and 12 mol% or less of poly-m-phenylene sulfide units. A film roll obtained by winding the laminated polyphenylene sulfide film according to any one of claims 1 to 4. A packaging material obtained by laminating a pair of the laminated polyphenylene sulfide films according to any one of claims 1 to 4 with a layer B interposed therebetween.