WO2013021816A1 - Mold release polyarylene sulfide film and manufacturing method for thermally hardened resin formed body using same - Google Patents

Abstract

Provided is a mold release polyarylene sulfide film with excellent mold release properties achieved by at least one surface of the film fulfilling both (1) and (2) shown below. (1) The center surface average roughness (SRa) is equal to or lower than 70 nm, and (2) the hardness at a depth of 10 nm measured by the nanoindentation method is at least 4.0 GPa.

Description

Polyarylene sulfide film for mold release and method for producing thermosetting resin molding using the same

The present invention relates to a release polyarylene sulfide film useful for molding a thermosetting resin, and also relates to a method for producing a thermosetting resin molding using the same.

When a heat press is performed with a mold in resin molding, a release film is used for the purpose of easily removing the molded body after the heat press from the mold and preventing the mold from being soiled.

Conventionally, as a release film, a fluorine-based film, a polymethylpentene film, a polypropylene film, a polyethylene terephthalate film, and the like have been used. However, although the fluorine-based film is excellent in releasability, it is expensive and has a problem that it is difficult to burn in waste incineration after use and generates toxic gas during combustion. Since the polymethylpentene film has a low softening temperature, there is a problem in that wrinkles easily enter the film during molding. Polypropylene films and polyethylene terephthalate films are relatively inexpensive, but are inferior in heat resistance and have insufficient releasability when used at high temperatures. For example, a release layer made of a thermosetting silicone release agent is laminated or coated on the surface of these films for the purpose of improving releasability. There is a risk that the quality of the product may be impaired by the transfer.

On the other hand, polyphenylene sulfide film (hereinafter abbreviated as PPS film) is excellent in heat resistance and chemical resistance and exhibits good releasability in a wide temperature range. Expectation as a release film is increasing. For example, a PPS film for mold release having improved surface smoothness and reduced surface defects by adjusting the particle addition concentration has been proposed (see Patent Documents 1 and 2).

In addition, in recent years, there are many cases where the press time is shortened and the productivity is improved by increasing the temperature of the heating press to 180 ° C. or higher, and the development of a release film with higher releasability is strong. It was desired. In such molding at a high temperature, the conventional PPS film may have insufficient releasability. For example, when the PPS film described in Patent Documents 1 and 2 is pressed at a temperature of 180 ° C. or higher, the film is molded. There was a possibility that the molded body could not be obtained due to the film being torn or cleaved during peeling and being in close contact with the body.

Japanese Patent Laid-Open No. 9-300365 JP 2008-110549 A JP 2001-154198 A

An object of the present invention is to provide a polyarylene sulfide film for mold release excellent in mold release properties.

In order to solve the above problems, the polyarylene sulfide film of the present invention mainly has the following constitution. That is,
(I) A film comprising a polyarylene sulfide resin, which is a polyarylene sulfide film for mold release satisfying both of the following (1) and (2) on at least one surface of the film;
(1): Center plane average roughness (SRa) is 70 nm or less (2): Hardness at a depth of 10 nm measured by the nanoindentation method is 4.0 GPa or more
(II) The polyarylene sulfide film for mold release according to (I), wherein the tensile modulus in the longitudinal direction and the width direction of the film are both 4.0 GPa or less.
(III) A step of placing a thermosetting resin preform on one of the surfaces of the film described in (I) that satisfies both (1) and (2), and using the mold, the thermosetting resin preform. A method for producing a thermosetting resin molded body including a step of forming by reforming by heating press molding,
(IV) The method for producing a thermosetting resin molded article according to (III), wherein the thermosetting resin is an epoxy resin,
It is.

According to the present invention, the releasability of the polyarylene sulfide film can be greatly improved, and even when used for shaping with a hot press at a high temperature of 180 ° C. or higher, film tearing, cleavage, etc. can occur. Therefore, the release film can be peeled off, and a thermosetting resin molding can be obtained efficiently.

Hereinafter, the present invention will be described.

The polyarylene sulfide used in the present invention is a homopolymer or copolymer having a repeating unit of — (Ar—S) — as a main constituent unit, preferably containing 80 mol% or more of the repeating unit. Ar includes repeating units represented by the following formulas (A) to (L), among which the repeating unit represented by the formula (A) is particularly preferable.

(In the formula, R1 and R2 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 are the same or different. May be good.)
As long as this repeating unit is a main constituent unit, it can contain a small amount of branching units or crosslinking units represented by the following formulas (M) to (P). The copolymerization amount of these branched units or cross-linked units is preferably in the range of 0 to 1 mol% with respect to 1 mol of — (Ar—S) — units.

The polyarylene sulfide used in the present invention may be any of a random copolymer having the above repeating unit, a block copolymer, and a mixture thereof.

Typical examples of these polyarylene sulfides include polyphenylene sulfide, polyphenylene sulfide sulfone, polyphenylene sulfide ketone, random copolymers thereof, block copolymers, and mixtures thereof. As a particularly preferred polyarylene sulfide, a polyphenylene sulfide containing a p-phenylene sulfide unit represented by the following formula as a main structural unit of the polymer is preferably 80 mol% or more, more preferably 90 mol%, still more preferably 95 mol% or more. (Hereinafter sometimes abbreviated as PPS). When the p-phenylene sulfide unit is less than 80 mol%, the crystallinity and heat transition temperature of the polymer are low, and the heat resistance, dimensional stability, mechanical properties and the like that are characteristic of the polyarylene sulfide film may be impaired.

In the present invention, the melt viscosity of the polyarylene sulfide is not particularly limited, but is preferably in the range of 100 to 2,000 Pa · s at a temperature of 310 ° C. and a shear rate of 1,000 (1 / sec). More preferably, it is in the range of 200 to 1,000 Pa · s. The molecular weight of polyarylene sulfide is not particularly limited, and general polyarylene sulfide can be used. The weight average molecular weight of such polyarylene sulfide is 5,000 to 1,000,000. For example, 7,500 to 500,000 is preferable, and 10,000 to 100,000 is more preferable.

The method for producing polyarylene sulfide is not particularly limited. For example, an aromatic compound or thiophene containing at least one nucleus-substituted halogen represented by JP-A-5-163349 is used as a polar organic solvent. It can be obtained by reacting at elevated temperature in the medium, preferably by contacting the sulfiding agent and the dihalogenated aromatic compound in an organic polar solvent.

In the present invention, the obtained polyarylene sulfide is subjected to crosslinking / high molecular weight by heating in air, heat treatment under an inert gas atmosphere such as nitrogen or reduced pressure, washing with an organic solvent, hot water, an acid aqueous solution, etc. It can also be used after various treatments such as activation with functional group-containing compounds such as anhydrides, amines, isocyanates and functional group disulfide compounds.

In the present invention, the polyarylene sulfide may be blended with a resin (heterogeneous polymer) other than the polyarylene sulfide as long as the properties of the present invention are not impaired, and the antioxidant, heat stabilizer, lubricant, UV absorption An additive such as an agent may be added.

In the present invention, the polyarylene sulfide can contain organic or inorganic particles. Examples of such particles include inorganic particles such as calcium carbonate, silica, titanium oxide, alumina, kaolin, calcium phosphate, barium sulfate, talc, zinc oxide, metal, polytetrafluoroethylene particles, silicone particles, and crosslinked polystyrene particles. And organic particles that do not melt up to 300 ° C. Preferably, they are calcium carbonate and silica, and these particles are preferable because they have good affinity with the polymer and it is difficult for voids to be generated around the particles during film formation stretching. The shape of the particles is not particularly limited, and particles such as spherical, rectangular parallelepiped, monodispersed, and aggregated particles can be used. One type of these particles may be used alone, or two or more types may be used in combination. The addition amount of the particles is preferably less than 5% by weight with respect to the entire film from the viewpoint of ensuring high releasability. When the content of the particles is 5% by weight or more, the surface roughness of the film is increased, so that the release film is strongly adhered to the molded body, and the releasability may be deteriorated.

The thickness of the release polyarylene sulfide film of the present invention is not particularly limited, but is preferably in the range of 1 to 500 μm, more preferably in the range of 3 to 250 μm, from the viewpoint of workability when used as a release film. More preferably, it is in the range of 5 to 100 μm.

Further, the polyarylene sulfide film for mold release of the present invention may be a stretched film or an unstretched film, and a film having suitable stretching conditions can be used depending on the application.

It is important that the center plane average roughness (SRa) of the polyarylene sulfide film for mold release of the present invention is 70 nm or less (referred to as surface property (1) for convenience). More preferably, it is 50 nm or less, More preferably, it is 30 nm or less. When the center surface average roughness exceeds 70 nm, the unevenness of the film surface increases the adhesion to the molded product, and the releasability may be insufficient when heated and pressed at a high temperature of 180 ° C. or higher. The lower limit of the center plane average roughness of the polyarylene sulfide film that can be industrially formed is 0.5 nm. In order to make the center plane average roughness within the above range, it can be appropriately adjusted depending on the content of particles, the average particle diameter of the particles, the draw ratio during film formation, the heat treatment temperature, etc.

In the polyarylene sulfide film for mold release according to the present invention, the hardness at a depth of 10 nm from the surface measured by the nanoindentation method is 4.0 GPa or more from the viewpoint of improving the mold release property (for convenience) Surface physical properties (2)). More preferably, it is 4.2 GPa or more, More preferably, it is 4.5 GPa or more. When the hardness is less than 4.0 GPa, releasability may be insufficient in a hot press at a high temperature of 180 ° C. or higher. On the other hand, the upper limit of the hardness is not particularly limited, but the upper limit is substantially about 10 GPa. As a method for achieving such hardness, for example, a rubbing treatment may be performed on the film surface as described later.

When the surface hardness is to be achieved by performing a rubbing treatment on the surface of the polyarylene sulfide film, the rubbing method is not particularly limited. For example, a known rubbing apparatus can be used (for example, a patent Reference 3). In that case, the rubbing conditions are adjusted so that the hardness value measured by the nanoindentation method on the surface of the rubbed film falls within the above-mentioned range.

In this case, rubbing is preferably performed under such a condition that the rubbing density (mm) represented by the following formula M is 300 mm or more, more preferably 500 mm or more, and still more preferably 700 mm or more. When the rubbing density is less than 300 mm, the hardness value measured by the nanoindentation method on the surface of the rubbed film may not fall within the aforementioned range.

M = NL (1 + 2πRn / 60V)
In the above formula, N is the number of times of rubbing, L is the length (mm) of the rubbing cloth touching the film surface, R is the radius (mm) of the rubbing roller including the thickness of the rubbing cloth, and n Is the number of rotations (rpm) of the rubbing roller, and V is the moving speed of the film (mm / s).

The time when the rubbing treatment is performed on the film surface is not particularly limited. For example, in the case of a biaxially stretched film, the unstretched film before stretching is rubbed, rubbed after being stretched in one direction, and stretched biaxially. For example, rubbing before winding after winding, and rubbing as post-processing after winding.

In the release polyarylene sulfide film of the present invention, it is important that at least one surface of the film satisfies both the surface physical properties (1) and the surface physical properties (2). A surface satisfying these surface physical properties (1) and (2) is preferably used as a release surface, and the surface physical properties of the opposite surface are not particularly limited. Therefore, depending on the application, the particle addition concentration may be different on both surfaces, and films having different resin structures are laminated on the surface opposite to the surface satisfying the surface physical properties (1) and (2). You can also.

Moreover, it is preferable that the polyarylene sulfide film for mold release according to the present invention has a tensile elastic modulus in the longitudinal direction and the width direction of 4.0 GPa or less. More preferably, it is 3.7 GPa or less, More preferably, it is 3.4 GPa or less. When either one of the tensile modulus in the longitudinal direction or the width direction of the film exceeds 4.0 GPa, the film may have insufficient moldability due to the rigidity of the film being too high.

The polyarylene sulfide film for mold release of the present invention can be suitably used as a mold release film when it is hot press molded using a mold. For example, when manufacturing printed circuit boards, IC chips (wafer molds), ceramic electronic parts, thermosetting resin products, decorative boards, etc., the metal plates and the resin are not bonded to each other during the molding process. It is sandwiched between boards and between resins, especially when manufacturing laminated boards, when manufacturing flexible printed boards, when molding epoxy resin compositions for semiconductor encapsulation, when manufacturing fiber reinforced composite materials, and when manufacturing sports and leisure goods The film is preferably used. Specifically, the release film used at the time of manufacturing the laminated board is, for example, for preventing adhesion between the printed board and the separator plate or another printed board in press molding when producing a multilayer printed board. A film that exists between the two. Moreover, the release film used at the time of manufacturing a flexible printed circuit board is specifically formed by etching or the like on a base film at the time of manufacturing a deformable flexible printed circuit board incorporated in a movable part of an electrical product. This refers to a film used to wrap the cover resin so that the cover resin adheres to the concavo-convex portion of the circuit when the cover resin for protecting the electrical circuit is heated and pressed. Specifically, the release film used at the time of molding the epoxy resin composition for semiconductor encapsulation is, for example, an epoxy resin material powder or tablet is cured and molded by a known molding method such as transfer molding or compression molding. In this case, it refers to a film that exists between the mold and the epoxy resin to prevent adhesion. Specifically, the release film used at the time of manufacturing the fiber reinforced composite material is, for example, a mold and an epoxy resin when manufacturing various products by curing and molding a carbon fiber prepreg using an epoxy resin as a matrix resin. It is a film used to prevent adhesion with the film. Specifically, the release film used in the manufacture of sports / leisure goods is, for example, curing a carbon fiber prepreg wound in a cylindrical shape in an autoclave when manufacturing fishing rods, golf club shafts, windsurfing poles, etc. When used, it is a film used to prevent adhesion with the mold.

The present invention is particularly preferably used to prevent adhesion between a mold and a prepreg when a prepreg formed by impregnating a reinforcing fiber base material with a matrix resin is molded with a press mold. As the composition of the prepreg suitably used, high-strength fibers such as carbon fiber, glass cloth, and aramid fiber can be used as the reinforcing fiber, and as the matrix resin to be impregnated, epoxy resin, unsaturated polyester resin, allyl resin, Thermosetting resins such as a phenol resin, a melamine resin, and a polyamide resin can be mentioned, and an epoxy resin is particularly preferable.

Next, a method for producing a polyarylene sulfide film for mold release according to the present invention will be described with reference to an example of a method for producing a biaxially oriented polyphenylene sulfide film using polyphenylene sulfide as the polyarylene sulfide, but the present invention is not limited thereto. Is not interpreted.

(1) Polymerization method of polyphenylene sulfide Sodium sulfide and p-dichlorobenzene are reacted in an amide polar solvent such as N-methyl-2-pyrrolidone (NMP) at high temperature and high pressure. If necessary, a copolymer component such as trihalobenzene can be included. Caustic potash or alkali metal carboxylate is added as a polymerization degree adjusting agent, and a polymerization reaction is performed at 230 to 280 ° C.

After the polymerization, the polymer is cooled, and the polymer is filtered through a filter as a water slurry to obtain a granular polymer. This is stirred in an aqueous solution of acetate or the like at 30 to 100 ° C. for 10 to 60 minutes, washed several times with ion exchange water at 30 to 80 ° C. and dried to obtain a PPS powder. The powder polymer is washed with NMP at an oxygen partial pressure of 10 Torr or less, preferably 5 Torr or less, then washed several times with ion exchange water at 30 to 80 ° C., and dried under a reduced pressure of 5 Torr or less. Since the powder polymer thus obtained is a substantially linear PPS polymer, stable stretch film formation becomes possible.

(2) Production method of particle-dispersed pellets The polyphenylene sulfide powder obtained as described above and a slurry in which particles are dispersed in a liquid are mixed, and the mixture is supplied to a vent extruder to simultaneously melt and knead the liquid. And the particles are dispersed in polyphenylene sulfide. In a preferred dispersion method, first, particles are finely dispersed in a liquid having a boiling point of 90 to 290 ° C. to form a slurry (hereinafter sometimes referred to as a particle slurry). Here, it is preferable to remove coarse particles and fine particles by filtration, decanter, or the like, if necessary. The average particle diameter of the particles is preferably in the range of 0.5 to 3.0 μm even in the particle slurry, and the particle concentration in the slurry is 80% by weight with respect to the total weight of the particle slurry from the viewpoint of preventing secondary aggregation. The following is preferred. Examples of the liquid include water, ethylene glycol, triethylene glycol, NMP, and diphenyl ether. Water, ethylene glycol, and triethylene glycol that do not dissolve polyphenylene sulfide at a temperature equal to or higher than the boiling point of the liquid are preferable.

Next, after mixing the above-described particle slurry with the polyphenylene sulfide powder, a method of supplying to the extruder having a vent hole, or supplying the polyphenylene sulfide powder to an extruder having a vent hole, and the polymer is melted before and / or The particle slurry is dispersed in the polyphenylene sulfide by removing the liquid component from the vent hole at the same time as the particle slurry is kneaded into the molten polyphenylene sulfide by a method such as forcibly injecting the particle slurry during melting. . Here, the ratio of the liquid component to the polyphenylene sulfide powder is preferably 30% by weight or less, and more preferably 20% by weight or less from the viewpoint of dispersibility and liquid component removal efficiency. The gut polymer discharged from the extruder is cooled in a water bath or the like by a conventional method, and then cut into pellets in which particles are dispersed in the polymer (hereinafter sometimes referred to as particle pellets).

Also, only the polyphenylene sulfide powder obtained in (1) can be pelletized (hereinafter, such pellets may be referred to as non-particle pellets) and mixed with the particle pellets during film production.

(3) Production of biaxially oriented polyphenylene sulfide film After drying the particle pellets and / or particle-free pellets obtained as described above under reduced pressure, the melting part of the extruder is heated to a temperature of 300 to 350 ° C, preferably Charge to an extruder heated to 310-340 ° C. Thereafter, the molten polymer passed through the extruder is passed through a filter, and the molten polymer is discharged into a sheet form using a die of a T die. The set temperature of the filter part and the die is preferably 3 to 20 ° C., more preferably 5 to 15 ° C. higher than the temperature of the melting part of the extruder. This sheet-like material is closely adhered to a cooling drum having a surface temperature of 20 to 70 ° C. to be cooled and solidified to obtain a substantially unoriented unstretched film.

Next, this unstretched film is biaxially stretched and biaxially oriented. Stretching methods include sequential biaxial stretching methods (stretching methods that combine stretching in each direction, such as a method of stretching in the width direction after stretching in the longitudinal direction), and simultaneous biaxial stretching methods (in the longitudinal direction and the width direction). A method of stretching simultaneously) or a method of combining them can be used. Here, an example using a sequential biaxial stretching method in which stretching in the longitudinal direction and then in the width direction is performed first will be described.

After heating the unstretched polyphenylene sulfide film with a heating roll group, it is 2.5 to 4.5 times, preferably 3.0 to 4.0 times, more preferably 3.1 to 3.times. In the longitudinal direction (MD direction). The film is stretched four times in one or more stages (MD stretching). When the draw ratio is less than 2.5, the flatness of the film may be significantly deteriorated during the subsequent heat treatment. The stretching temperature is preferably 70 to 130 ° C, more preferably 80 to 110 ° C. Thereafter, it is cooled by a cooling roll group of 20 to 50 ° C.

As a stretching method in the width direction (TD direction) following MD stretching, for example, a method using a tenter is common. The both ends of this film are gripped with clips, guided to a tenter, and stretched in the width direction (TD stretching). The stretching temperature is preferably 70 to 130 ° C, more preferably 80 to 110 ° C. The draw ratio is in the range of 2.5 to 4.5 times, preferably 3.0 to 4.0 times, more preferably 3.1 to 3.4 times.

Next, this biaxially stretched film is heat-treated under tension. The heat treatment temperature is preferably in the range of 160 to 280 ° C., and the heat treatment is performed in one or more stages. At this time, it is preferable from the viewpoint of thermal dimensional stability that a relaxation treatment is performed in the range of 0 to 10% in the film width direction at the heat treatment temperature. When performing the second stage heat treatment, the first stage heat treatment temperature should be in the range of 160 to 220 ° C., and the second stage heat treatment temperature should be in the range of 230 to 280 ° C. and higher than the first stage temperature. It is preferable for improving the flatness of the film and for stable film formation. After the heat treatment, the film is cooled to room temperature.

(4) Rubbing treatment The biaxially oriented polyphenylene sulfide film obtained as described above is rubbed using a rubbing apparatus. A known rubbing apparatus may be used. The outline is performed by pressing a roll wrapped with a rubbing cloth against the film and relatively moving the roll while rotating it. The rotation direction of the roll is preferably the forward direction of the flocking direction of the wound rubbing cloth, and is preferably rotated in the direction opposite to the moving direction of the film. In addition, you may make it contact a roll axis | shaft and the moving direction of the said film at a certain angle (theta). The strength of rubbing can be changed as appropriate depending on the peripheral speed ratio, the amount of pushing, and the like. Peripheral speed ratio is the value obtained by dividing the relative roll linear velocity by the relative film moving speed, and the indentation amount is the rubbing cloth (roll) from the position where the film surface and the rubbing cloth surface are generally in contact with the film surface. It is the length to press on. As the material for the rubbing cloth, cellulose acetate, cotton, rayon, polyamide, acrylic, aramid and the like are preferably used. As the form of the rubbing cloth, a nonwoven fabric, a pile weave, and a velvet weave are preferable. The rubbing direction is preferably parallel to the rotation direction of the rubbing roller with respect to the longitudinal direction (MD direction) of the film from the viewpoint of improving productivity. In addition, from the viewpoint of preventing dust and the like from adhering to the film, it is preferable to perform static elimination by static elimination after rubbing. The polyphenylene sulfide film obtained as described above can be suitably used as a release film.

The physical property value measurement method and the effect evaluation method are as follows.
(1) Center plane average roughness (SRa)
Using a SURF CORDER ET 4000A manufactured by Kosaka Laboratory, the center surface average roughness (SRa) of the surface was determined under the following conditions.

Stylus radius of curvature: 2 μm
Cut-off: 0.25mm
Measurement length: 0.5mm
Measurement interval: 5 μm
Number of measurements: 80 times.

(2) Nanoindentation hardness Measurement was performed by a nanoindentation method using an ultra-small hardness meter “Nano Indenter DCM” manufactured by MTS Systems. An indentation load / unloading test was performed using a diamond regular triangular pyramid indenter, and a load-indentation depth diagram was obtained. At this time, the hardness H at the maximum load Pmax is calculated from the following equation.
H = Pmax / A
In the above formula, A is the projected area of the indentation, and is a value calculated using the effective contact depth calculated from the load-indentation depth diagram. The measurement was performed 10 times under the following conditions, and the average value of the hardness when the indentation depth was 10 nm was determined.
Measurement conditions Measuring device: Ultra-small hardness meter Nano Indenter DCM manufactured by MTS Systems
Measurement method: Nanoindentation method (continuous stiffness measurement method)
Working indenter: Diamond regular triangular pyramid indenter Maximum indentation depth: Approximately 3 μm
Measurement atmosphere: 25 ° C. in air.

(3) Tensile modulus According to the method specified in ASTM-D882, the tensile modulus was measured using an Instron type tensile tester under the following conditions. About the longitudinal direction and the width direction of a film, the sample was changed, the measurement was performed 10 times, and the average value was obtained.

Measuring device: “Tensilon AMF / RTA-100” automatic strength measuring device for film strength made by Orientec Co., Ltd.
Sample size: width 10mm x test length 100mm
Tensile speed: 300 mm / min Measurement environment: 25 ° C., 65% RH.

(4) Film thickness Ten points were measured using a dial gauge thickness meter (manufactured by Mitutoyo Corporation), and an average value was obtained.

(5) Evaluation of releasability by mold molding test Two samples of prepreg (Toray, product number: 3252S-15) made of carbon fiber and epoxy resin cut into a size of 29 cm x 29 cm, cut into a size of 30 cm x 30 cm I sandwiched it with film. At this time, the layers were laminated so that the rubbed surface was in contact with the prepreg. After applying a pressure of 2 MPa for 5 minutes with a press molding machine (flat plate mold) with the mold temperature adjusted to 200 ° C., the laminate is taken out and cooled sufficiently at room temperature, and then the prepreg and the sample film are removed by hand. I peeled it off. The releasability at the time of peeling was judged according to the following criteria. C is rejected.
Releasability A: The film was easily peeled off from the prepreg without breaking. B: The film was partially broken but peeled off from the prepreg. C: Strongly adhered and not peeled off from the prepreg.

(6) Formability evaluation by mold molding test A central cylindrical projection having a diameter of 5 cm and a height of 7 mm is provided. Exhaust for vacuum suction at six locations along the circumference of the projection. A male mold (size 15 × 25 cm) with holes (hole diameter 1 mm) opened at equal intervals was created and attached to a vacuum molding machine (device name: forming 300 type) manufactured by Seiko Sangyo Co., Ltd. Cut the sample film into A4 size and attach it to the device, preheat the sample film for 10 seconds using the ceramic heater attached to the device heated to 350 ° C., and then press the unheated mold against the sample film, Immediately after the pressing, a film was formed by vacuum suction through an exhaust hole for 30 seconds. At this time, since the sample film cannot sufficiently follow the shape of the protrusion of the mold, the sample film draws an inclination starting from the upper end of the protrusion and sticks to the mold. The linear distance between the two points on the plane projected from the upper circle side of the protrusion (the point of contact between the film and the protrusion and the contact point of the protrusion bottom circle at the contact point between the film and the protrusion) is observed as a substantially concentric circle. Measured 10 points with a vernier caliper (extract 10 points evenly from the entire circumference), and the average value was taken as the skirt width. The moldability at the time of molding was judged according to the following criteria. C is rejected.
Formability A: Bottom width is less than 1 cm B: Bottom width is 1 cm or more and less than 2 cm C: Bottom width is 2 cm or more.

(1) Preparation of polyphenylene sulfide powder In an autoclave, 47% sodium hydrosulfide 9.44 kg (80 mol), 96% sodium hydroxide 3.43 kg (82.4 mol), N-methyl-2-pyrrolidone (NMP) 13 1.0 kg (131 mol), sodium acetate 2.86 kg (34.9 mol), and ion-exchanged water 12 kg, gradually heated to 235 ° C. over about 3 hours under nitrogen at normal pressure, and 17.0 kg of water And after distilling 0.3kg (3.23 mol) of NMP, the reaction vessel was cooled to 160 ° C. Next, 11.5 kg (78.4 mol) of p-dichlorobenzene (p-DCB), 0.007 kg (0.04 mol) of 1,2,4-trichlorobenzene and 22.2 kg (223 mol) of NMP were additionally added. The reaction vessel was sealed under nitrogen gas and heated 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 further continued at 270 ° C. for 100 minutes. Thereafter, 1.60 kg (88.8 mol) of water was again injected into the system, 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 contents were taken out, diluted with 32 liters of NMP, and the solvent and solid matter were filtered off with a sieve (80 mesh). The resulting particles were again washed with 85 liters of NMP at 85 ° C. Thereafter, it was washed 5 times with 67 liters of warm water and filtered, washed 5 times with 70,000 g of 0.05 wt% aqueous calcium acetate solution and filtered to obtain PPS polymer particles. This was dried in hot air at 60 ° C. and dried under reduced pressure at 120 ° C. for 20 hours to obtain white polyphenylene sulfide powder.

(2) Preparation of particle-free pellets The polyphenylene sulfide powder obtained in (1) was supplied to a vent extruder having a 30 mm diameter biaxial screw and melted at a temperature of 320 ° C. The melt was passed through a filter made of metal fibers with a 95% cut hole diameter of 10 μm and then extruded from a 2 mm hole diameter die to obtain a gut-like resin composition. Further, the composition was cut into a length of about 3 mm to obtain polyphenylene sulfide non-particle pellets.

(3) Production of particle pellets A slurry was prepared by dispersing 50% by weight of calcium carbonate particles having an average particle diameter of 1.2 μm in ethylene glycol. The slurry was filtered through a filter and then mixed with the polymer obtained in (1) using a Henschel mixer. At this time, mixing was performed so that the weight of calcium carbonate was 20% by weight with respect to the weight of the polymer obtained in (1). The obtained mixture was supplied to a vent extruder having a 30 mm diameter biaxial screw and melted at a temperature of 320 ° C. The melt was passed through a filter made of metal fibers with a 95% cut hole diameter of 10 μm and then extruded from a 2 mm hole diameter die to obtain a gut-like resin composition. Further, the composition was cut into a length of about 3 mm to obtain particle pellets having a particle content of 20% by weight.

(Example 1)
After mixing the non-particle pellets and the particle pellets obtained above so that the content of calcium carbonate is 0.5% by weight with respect to the weight of the polyphenylene resin, 3 mmHg is used using a rotary vacuum dryer. It was dried at a temperature of 180 ° C. for 4 hours under reduced pressure. The obtained dried chip was supplied to a full flight single screw extruder whose melting part was heated to 310 ° C., filtered through a filter set at a temperature of 320 ° C., and then from a die of a T die set at a temperature of 310 ° C. It was melt-extruded and closely cooled and solidified while applying an electrostatic charge to a cast drum having a surface temperature of 25 ° C. to produce an unstretched film.

This unstretched film was heated 3.5 times in the longitudinal direction of the film at a film temperature of 101 ° C. using a difference in peripheral speed of the roll after preheating using a longitudinal stretching machine composed of a plurality of heated roll groups. Stretched at a magnification. Thereafter, both ends of the film are held with clips and guided to a tenter, stretched in the width direction of the film at a stretching temperature of 101 ° C. and a stretching ratio of 3.7 times, and subsequently heat treated at a temperature of 260 ° C. for 10 seconds. It was. During the heat treatment, a relaxation treatment of 5% was performed in the film width direction. After the film was cooled to room temperature, the film edge was removed to prepare a biaxially oriented PPS film having a thickness of 25 μm.

One side of the produced film was uniformly rubbed using a rubbing apparatus manufactured by Newtom. As the rubbing cloth, a pile cloth made of rayon was used, and rubbing was performed under the condition that the rubbing density was 1000 mm. Table 1 shows the average roughness and nanoindentation hardness of the rubbed surface. When this film was used to evaluate releasability, excellent releasability was shown as shown in Table 1.

(Example 2)
In Example 1, except that the non-particle pellets and the particle pellets were mixed so that the calcium carbonate content was 2.0% by weight with respect to the weight of the polyphenylene resin. A PPS film was prepared. The film properties and releasability are as shown in Table 1. Although film tearing occurred, the adhesion resistance was small and there was no problem with releasability.

(Example 3)
Example 1 is the same as Example 1 except that the thickness of the unstretched film was adjusted to 25 μm by adjusting the extrusion amount of the melt extrusion and the speed of the cast drum, and then the surface was rubbed without stretching. In the same manner as described above, a PPS film for release was prepared. The film properties and releasability are as shown in Table 1, showing excellent releasability.

(Example 4)
In Example 1, the draw ratio of longitudinal drawing was 3.2 times, the draw ratio in the width direction was 3.1 times, and heat setting was 190 ° C. (5 seconds) in the first stage, and 260 ° C. (5 seconds) in the second stage. A PPS film for release was prepared in the same manner as in Example 1 except that the two steps were performed. The film properties and releasability are as shown in Table 1, showing excellent releasability.

(Example 5)
A release PPS film was produced in the same manner as in Example 1 except that the draw ratio of longitudinal stretching was 4.1 times and the stretch ratio in the width direction was 4.0 times. The film properties and releasability are as shown in Table 1, showing excellent releasability.

(Comparative Example 1)
A release PPS film was prepared in the same manner as in Example 1 except that in Example 1, the film was not rubbed. The film properties and releasability were as shown in Table 1. The film was in strong contact and could not be peeled off.

(Comparative Example 2)
A release PPS film was produced in the same manner as in Example 1 except that the push amount during rubbing was 0.1 mm in Example 1. The film properties and releasability were as shown in Table 1. The film was in strong contact and could not be peeled off.

(Comparative Example 3)
In Example 2, a release PPS film was produced in the same manner as in Example 2 except that the film was not rubbed. The film properties and releasability were as shown in Table 1. The film was in strong contact and could not be peeled off.

(Comparative Example 4)
A release PPS film was prepared in the same manner as in Example 1 except that the non-particle pellets and the particle pellets were mixed in Example 1 so that the calcium carbonate content was 5.0% by weight. The film properties and releasability were as shown in Table 1. The film was in strong contact and could not be peeled off.

The release polyarylene sulfide film of the present invention can be used as a release film for smoothly releasing from a mold in a molding process such as molding of a carbon fiber-epoxy resin prepreg.

Claims (4)

A polyarylene sulfide film for release, which is a film made of a polyarylene sulfide resin and satisfies both of the following (1) and (2) on at least one side of the film.
(1): Center plane average roughness (SRa) is 70 nm or less (2): Hardness at a depth of 10 nm measured by the nanoindentation method is 4.0 GPa or more 2. The polyarylene sulfide film for mold release according to claim 1, wherein the tensile modulus in the longitudinal direction and the width direction of the film are both 4.0 GPa or less. A step of placing a thermosetting resin preform on one of the surfaces of the film according to claim 1 that satisfies both (1) and (2), and heating the thermosetting resin preform using a mold. A method for producing a thermosetting resin molded body, comprising a step of forming by press molding. The method for producing a thermosetting resin molded article according to claim 3, wherein the thermosetting resin is an epoxy resin.