JP2013006401A - Resin film production apparatus, resin film production process, and resin film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin film production apparatus allowing quality improvement by preventing defects from occurring.SOLUTION: The resin film production apparatus 100 forms a surface shape of filmy resin extruded from a die 2 into a predetermined shape by pinching the filmy resin with outer peripheral surfaces of both a rubber roll 3 and mat roll 4 so as to produce the resin film. The resin film production apparatus 100 is equipped with a heating device 10 having first and second heating sections 8 and 9 for heating the outer peripheral surface of the rubber roll 3. The first heating section 8 is provided facing the rubber roll 3 in an area on the side where the die 2 is arranged in a virtual plane S0 including rotary shafts of rubber roll 3 and mat roll 4. Also, the second heating section 9 is provided facing the rubber roll 3 in an area opposite to the side where the die 2 is arranged in the virtual plane S0.

Description

  The present invention relates to a resin film provided with optical properties, a resin film manufacturing apparatus, and a resin film manufacturing method.

  Optical sheets used for optical applications are widely used for liquid crystal cells, retardation films, diffusion films, brightness enhancement films and the like combined with optical disks and polarizing plates, for example.

  Light transmission characteristics and reflection characteristics (hereinafter referred to as “optical characteristics”) in the optical sheet are determined by the material of the optical sheet, the state of the optical sheet surface, and the like. A resin material is often used as the material of the optical sheet. Some optical sheets have, for example, a concavo-convex shape formed on the surface of a resin film and a function of scattering light.

  The resin film having a concavo-convex shape formed on the surface thereof is generally a first cooling roll having a smooth outer peripheral surface by extruding a molten transparent resin from a die into a film shape, and a second cooling roll having an concavo-convex shape formed on the outer peripheral surface. Is obtained by transferring the concavo-convex shape of the second cooling roll and winding it around the second cooling roll, and then taking it out with a take-up roll.

  Patent Document 1 discloses a method for producing a resin film. In the method for producing a resin film disclosed in Patent Document 1, a resin material that is a pelletized thermoplastic resin is heated and melted, an extruder that extrudes the melted resin, and a molten state extruded from the extruder A resin film is manufactured using a resin film manufacturing apparatus including a die for extruding a resin into a film and a plurality of rolls that sandwich the resin extruded into a film from the die.

  Since the surface state of a plurality of rolls sandwiching the resin is reflected in the surface state of the resin film, for example, when it is desired to provide unevenness on the surface of the resin film, the surface of the roll is provided with unevenness and transferred to a plate. . When the surface of the resin film is desired to be flat, the roll surface is smoothed.

JP 2009-196327 A

  The optical characteristics of the resin film having a concavo-convex shape formed on the surface are affected by the degree of transfer of the concavo-convex of the roll serving as a plate. The degree of unevenness transfer is affected by the temperature of the surface of the plate roll and the roll that sandwiches the resin in pairs. When a non-uniform temperature portion exists on the surface of the roll, a streak-like defect portion extending in the flow direction of the resin film is generated on the surface of the resin film corresponding to the non-uniform temperature portion.

  An object of the present invention is to provide a resin film manufacturing apparatus, a resin film manufacturing method, and a resin film capable of suppressing the occurrence of defective portions and improving the quality.

The present invention is a resin film manufacturing apparatus for manufacturing a resin film made of a thermoplastic resin by a melt extrusion molding method,
A film forming means for forming a film by extruding a molten thermoplastic resin into a film;
It consists of a first roll and a second roll, the rotation axis of the first roll and the rotation axis of the second roll are parallel, and the outer peripheral surface of the first roll and the outer peripheral surface of the second roll are in contact with each other. The film-shaped thermoplastic resin extruded from the film-forming means is sandwiched between the outer peripheral surface of the first roll and the outer peripheral surface of the second roll, thereby forming a film-shaped thermoplastic resin. Molding means for molding the surface shape of the thermoplastic resin into a predetermined shape;
A heating means for heating the outer peripheral surface of the first roll, in a region on the side where the film forming means is disposed with respect to a virtual plane including the rotation axis of the first roll and the rotation axis of the second roll The first heating unit provided to face the first roll and the region opposite to the side on which the film forming means is disposed with respect to the virtual plane are provided to face the first roll. It is a resin film manufacturing apparatus provided with the heating means which has a 2nd heating part.

  Moreover, in the resin film manufacturing apparatus of the present invention, the first heating unit is a heating element group including a plurality of heating elements arranged at predetermined intervals along the axial direction over the entire axial direction of the first roll. It is characterized by including.

  Moreover, in the resin film manufacturing apparatus of this invention, when it sees from the circumferential direction of the said 1st roll in the said heat generating body group, a several zigzag is overlapped so that a part may mutually overlap in the axial direction. It is characterized by being arranged in a shape.

  Moreover, in the resin film manufacturing apparatus of this invention, the said 1st heating part is formed with the said several heating element group in the circumferential direction of a said 1st roll, It is characterized by the above-mentioned.

  Moreover, in the resin film manufacturing apparatus of this invention, the said 2nd heating part is provided directly under the said 1st roll in the direction perpendicular | vertical to the said virtual plane.

Further, the present invention is a method for producing a resin film comprising a thermoplastic resin by a melt extrusion molding method,
A film forming step of forming a film by extruding a molten thermoplastic resin into a film by a film forming means;
A molding step of molding a film-like thermoplastic resin extruded from the film-forming means by molding means comprising a first roll and a second roll, wherein the outer peripheral surface of the first roll and the outer periphery of the second roll Including a molding step of molding the surface shape of the film-like thermoplastic resin into a predetermined shape by sandwiching with the surface,
In the molding step, the outer peripheral surface of the first roll is heated by a heating means,
The heating means is provided to face the first roll in a region on the side where the film forming means is disposed with respect to a virtual plane including the rotation axis of the first roll and the rotation axis of the second roll. It has a 1st heating part and the 2nd heating part provided facing the 1st roll in the field opposite to the side where the film forming means is arranged to the virtual plane, This is a method for producing a resin film.

The present invention is a resin film imparted with optical properties,
A plurality of points are measured at equal intervals in the width direction at the time of manufacture, and the standard deviation of haze is 2.0 or less when this is measured as a single measurement row and a plurality of rows are measured at equal intervals in the flow direction. It is a resin film.

  According to the present invention, the resin film manufacturing apparatus sandwiches the film-like thermoplastic resin extruded from the film-forming means between the outer peripheral surface of the first roll and the outer peripheral surface of the second roll, so that the film-like heat This is an apparatus for producing a resin film by shaping the surface shape of a plastic resin into a predetermined shape. And a resin film manufacturing apparatus is provided with the heating means which has a 1st heating part and a 2nd heating part which heat the outer peripheral surface of a 1st roll. The first heating unit is provided to face the first roll in a region on the side where the film forming means is disposed with respect to a virtual plane including the rotation axis of the first roll and the rotation axis of the second roll. Further, the second heating unit is provided to face the first roll in a region opposite to the side on which the film forming means is disposed with respect to the virtual plane.

  In the resin film manufacturing apparatus configured as described above, the first heating provided to face the outer peripheral surface of the first roll in each of the region on the side where the film forming means is disposed and the region on the opposite side thereof. Since the outer peripheral surface of the first roll can be sufficiently heated by the part and the second heating unit, it is possible to suppress the occurrence of a non-uniform temperature portion in the axial direction on the outer peripheral surface of the first roll. . For this reason, the resin film manufacturing apparatus generates unevenness in the width direction of the resin film corresponding to the axial direction of the first roll, suppresses the generation of streak-like defect portions extending in the flow direction of the resin film, and improves quality. Can be made.

  According to the invention, the first heating unit is configured to include a heating element group including a plurality of heating elements arranged at predetermined intervals along the axial direction over the entire axial direction of the first roll. The Accordingly, the heating in the axial direction on the outer peripheral surface of the first roll can be controlled with high accuracy independently by each heating element arranged in the axial direction, so the temperature in the axial direction on the outer peripheral surface of the first roll. It is possible to more effectively suppress the occurrence of non-uniform portions.

  Further, according to the present invention, the plurality of heating elements in the heating element group are arranged in a staggered pattern so as to partially overlap each other adjacent to each other in the axial direction when viewed from the circumferential direction of the first roll. Yes. Accordingly, when the heating element group is viewed as a whole, the heating elements are arranged to face each other without any gap in the axial direction on the outer peripheral surface of the first roll, so that the axial direction on the outer peripheral surface of the first roll. It is possible to more effectively suppress the occurrence of a non-uniform temperature portion.

  According to the invention, the first heating unit is formed with a plurality of rows of heating element groups in the circumferential direction of the first roll. Accordingly, the heating control in the axial direction on the outer peripheral surface of the first roll can be performed independently and with high accuracy by each of the plurality of rows of heating elements arranged in the axial direction. It is possible to more effectively suppress the occurrence of a non-uniform temperature portion in the direction.

  According to the invention, the second heating unit is provided directly below the first roll in a direction perpendicular to the virtual plane. Accordingly, since the separation distance between the first heating unit and the second heating unit can be sufficiently increased with respect to the circumferential direction of the first roll, the outer peripheral surface of the first roll is set to the first heating unit and the second heating unit. Therefore, it is possible to more effectively suppress the occurrence of a portion having a non-uniform temperature in the axial direction on the outer peripheral surface of the first roll.

  Moreover, according to this invention, the manufacturing method of a resin film includes a film forming process and a shaping | molding process. In the film forming process, the molten thermoplastic resin is extruded into a film by a film forming means to form a film. In the forming step, the surface shape of the film-like thermoplastic resin is predetermined by sandwiching the film-like thermoplastic resin extruded from the film forming means between the outer peripheral surface of the first roll and the outer peripheral surface of the second roll. Mold into shape.

  Here, in the forming step, the outer peripheral surface of the first roll is heated by a heating means. The heating means is a first heating unit provided opposite to the first roll in a region on the side where the film forming means is disposed with respect to a virtual plane including the rotation axis of the first roll and the rotation axis of the second roll. And a second heating unit provided opposite to the first roll in a region opposite to the side on which the film forming means is disposed with respect to the virtual plane.

  In the forming step, the heating means includes a first heating unit and a second heating provided to face the outer peripheral surface of the first roll in each of the region on the side where the film forming unit is disposed and the region on the opposite side. Since the outer peripheral surface of the first roll can be sufficiently heated by the portion, it is possible to suppress the occurrence of a non-uniform temperature portion in the axial direction on the outer peripheral surface of the first roll. Therefore, in the method for producing a resin film, the occurrence of non-uniform defects in the width direction of the resin film corresponding to the axial direction of the first roll and the generation of streak-like defect portions extending in the flow direction of the resin film is suppressed, and the quality is improved. Can be improved.

  Further, according to the present invention, the resin film is measured at a plurality of points at equal intervals in the width direction at the time of manufacture, and the standard deviation of haze when the plurality of lines are measured at equal intervals in the flow direction as a single measurement column. 2.0 or less. As a result, a resin film having a uniform haze, which is an optical property, can be provided.

It is a figure which shows typically the structure of the resin film manufacturing apparatus 100 which is 1st Embodiment of this invention. It is a perspective view which expands and shows the principal part of the resin film manufacturing apparatus. It is the schematic of the resin film manufacturing apparatus 100 seen from the rotating shaft direction of the rubber roll. It is a perspective view which shows the structure of the resin film manufacturing apparatus 200 which is 2nd Embodiment of this invention. It is a perspective view which shows the structure of the resin film manufacturing apparatus 300 which is 3rd Embodiment of this invention.

  FIG. 1 is a diagram schematically showing a configuration of a resin film manufacturing apparatus 100 according to the first embodiment of the present invention. The resin film manufacturing apparatus 100 is an apparatus that manufactures a resin film made of a thermoplastic resin by a melt extrusion molding method. The resin film manufacturing method of the present invention is realized by the resin film manufacturing apparatus 100.

  Examples of the thermoplastic resin that can be used in the present invention include rubber-reinforced styrene resins such as polystyrene, high impact polystyrene, and medium impact polystyrene, styrene-acrylonitrile copolymer (SAN resin), and acrylonitrile-butyl acrylate rubber. Styrene copolymer (AAS resin), acrylonitrile-ethylenepropyl rubber-styrene copolymer (AES), acrylonitrile-polyethylene chloride-styrene copolymer (ACS), ABS resin (for example, acrylonitrile-butadiene-styrene copolymer, Styrenic resins such as acrylonitrile-butadiene-styrene-alphamethylstyrene copolymer, acrylonitrile-methyl methacrylate-butadiene-styrene copolymer), and polymethyl Acrylic resins such as tacrylate (PMMA), olefin resins such as low density polyethylene (LDPE), high density polyethylene (HDPE) and polypropylene (PP), vinyl chloride resins such as polyvinyl chloride and polyvinylidene chloride, ethylene chloride Vinyl chloride vinyl acetate copolymer, vinyl chloride copolymer resins such as ethylene vinyl chloride copolymer, polyester resins such as polyethylene terephthalate (PETP, PET), polybutylene terephthalate (PBTP, PBT), polycarbonate (PC), modified Polycarbonate resins such as polycarbonate, polyamide resins such as polyamide 66, polyamide 6 and polyamide 46, polyacetal (POM) resins such as polyoxymethylene copolymers and polyoxymethylene homopolymers, other en Nearing resin, super engineering resin, for example, polyethersulfone (PES), polyetherimide (PEI), thermoplastic polyimide (TPI), polyetherketone (PEK), polyetheretherketone (PEEK), polyphenylene sulfide (PSU) And cellulose derivatives such as cellulose acetate (CA), cellulose acetate butyrate (CAB), and ethyl cellulose (EC), and liquid crystal polymers such as liquid crystal polymers and liquid crystal aromatic polyesters. Also, thermoplastic polyurethane elastomer (TPU), thermoplastic styrene butadiene elastomer (TSBC), thermoplastic polyolefin elastomer (TPO), thermoplastic polyester elastomer (TPEE), thermoplastic vinyl chloride elastomer (TPVC), thermoplastic polyamide elastomer (TPAE) ) Etc. can also be used. In the present embodiment, a blend of one or more thermoplastic resins may be used, or an additive or the like may be contained.

  The resin film manufacturing apparatus 100 includes an extruder 1, a filtration apparatus 11, a die 2 that is a film forming means, a rubber roll 3 that is a first roll, a mat roll 4 that is a second roll, a mirror roll 5, It includes a take-up roll 6, an urging device 7, and a heating device 10 that is a heating means. In the present embodiment, the molding means is constituted by a rubber roll 3 and a mat roll 4.

  The extruder 1 includes an unillustrated extruder cylinder, a heater, and an extruder screw. In the extruder cylinder, the extruder 1 melts the thermoplastic resin by heat from the heater and shear friction heat of the extruder screw, and extrudes the molten thermoplastic resin (molten resin) by the extruder screw. Send to filtration device 11.

  The filtration device 11 includes a polymer filter and performs a filtration process on the molten resin extruded from the extruder 1. Specifically, it is filtered by passing a molten resin through a polymer filter to remove foreign substances such as gelled products.

  The die 2 is formed by extruding the molten resin after the filtration treatment into a film shape. As the die 2, for example, a T die can be used.

  The rubber roll 3 and the mat roll 4 are made of a cylindrical member having the same outer diameter, and the rotation axes of the two rolls are arranged on the same horizontal plane. The rubber roll 3 and the mat roll 4 may be disposed so that the outer peripheral surfaces are brought into contact with each other to form a nip portion, or the outer peripheral surfaces may be disposed with a predetermined gap (gap) therebetween. How to arrange may be set according to the characteristics required for the resin film to be manufactured. In the present embodiment, the urging device 7 urges the rubber roll 3 against the mat roll 4, so that the outer peripheral surface of the rubber roll 3 and the outer peripheral surface of the mat roll 4 come into contact with each other to form a nip portion.

  The die 2 is provided above the rubber roll 3 and the mat roll 4, and the discharge port of the die 2 is disposed open downward. The discharge port of the die 2 is positioned vertically above the nip portion between the rubber roll 3 and the mat roll 4, and the film-like resin discharged from the die 2 extends vertically downward and rotates in the opposite direction to the rubber roll 3 ( It is sandwiched between the rotation direction A1) and the mat roll 4 (rotation direction A2).

  When the film-like resin discharged from the die 2 is sandwiched between the rubber roll 3 and the mat roll 4, the rubber layer of the rubber roll 3 is elastically deformed into a concave shape along the outer peripheral surface of the mat roll 4 via the film-like resin. As a result, the rubber roll 3 and the mat roll 4 come into contact with each other with a predetermined nip length via the film-like resin.

  The nip length is a length that allows the uneven shape formed on the surface of the mat roll 4 to be transferred to the film-like resin. In order to set the nip length to a predetermined value, it can be arbitrarily set by adjusting, for example, the rubber layer material and the rubber layer thickness of the rubber roll 3.

  Since the film-like resin discharged from the die 2 is in a highly flexible state, the film surface shape corresponding to the outer surface of each roll can be obtained by being sandwiched between the rubber roll 3 and the mat roll 4. .

  The rubber roll 3 includes a metal core material and a rubber layer provided on the surface of the core material, and an iron core is used as the core material. The rubber layer is made of silicone rubber, fluorine rubber, or the like, and the hardness of the rubber material constituting the rubber layer is in the range of A70 to A90 in durometer hardness defined by JIS K6253. Further, the rubber layer contains a colorant for improving the response to far infrared rays emitted from the heating device 10 described later, and a filler such as silica powder for improving the thermal conductivity. The rubber roll 3 has a smooth outer surface, that is, the surface of the rubber layer, and flattens one surface of the film-like resin on the rubber roll 3 side. The outer peripheral surface of the rubber roll 3 is heated by a heating device 10 to be described later so as to have a predetermined temperature lower than the temperature of the film-like resin.

  The mat roll 4 is a metal roll whose surface has been subjected to minute unevenness, and transfers the uneven shape to the other surface of the film-like resin on the mat roll 4 side. In detail, for example, a metal roll that can control the temperature of the roll surface through fluid, steam, etc. inside a roll such as a drilled roll or a spiral roll having a hollow structure, and the outer peripheral surface of these metal rolls. What formed desired uneven | corrugated shape by sandblasting, engraving, etc. can be used.

  Examples of the uneven shape formed on the outer peripheral surface of the mat roll 4 include a mat shape having an arithmetic average surface roughness (Ra) of 0.1 to 10 μm, a prism shape and a lens shape having a pitch and height of 5 to 500 μm, and the like. Can be adopted. The arithmetic average surface roughness (Ra) is a value obtained by measuring with a surface roughness meter in accordance with JIS B0601-2001.

  The rubber roll 3 and the mat roll 4 are both held at a temperature lower than that of the film-like resin, and the film-like resin is cooled to a predetermined temperature by being sandwiched between the rubber roll 3 and the mat roll 4. Is done. By this cooling, the flexibility of the film-like resin is lowered, and the film-shaped resin is conveyed along with the rotation (rotation direction A2) of the mat roll 4 while being wound around the outer peripheral surface of the mat roll 4.

  The surface temperature (T) of the mat roll 4 is (Th−60 ° C.) ≦ T ≦ (Th + 30 ° C.), preferably (Th−30 ° C.) ≦ T ≦ with respect to the thermal deformation temperature (Th) of the film-like resin. (Th + 20), more preferably (Th−20 ° C.) ≦ T ≦ (Th + 10 ° C.).

  Here, the heat distortion temperature (Th) of the thermoplastic resin is not particularly limited, but is usually 60 to 200 ° C. The heat distortion temperature (Th) of the thermoplastic resin is a temperature measured according to ASTM D-648.

  The surface temperature of the rubber roll 3 is usually 0 to 70 ° C, preferably 20 to 40 ° C. On the other hand, if the surface temperature of the rubber roll 3 deviates to a higher side than the above range, the film may be taken up and wound around the rubber roll 3.

  The surface temperature of the rubber roll 3 is controlled within the specific range described above by heating the outer peripheral surface by the heating device 10. The heating apparatus 10 will be described below with reference to FIGS. 2 and 3. FIG. 2 is an enlarged perspective view showing a main part of the resin film manufacturing apparatus 100. FIG. 3 is a schematic view of the resin film manufacturing apparatus 100 viewed from the rotation axis direction of the rubber roll 3.

  The heating device 10 includes a first heating unit 8 and a second heating unit 9. The first heating unit 8 includes a first heating element group 81 and a second heating element group 82 that are provided in a row at a predetermined interval in the circumferential direction of the rubber roll 3. In the first heating unit 8, the second heating element group 82 is provided closer to the die 2 with respect to the circumferential direction of the rubber roll 3 than the first heating element group 81.

In the first heating element group 81, a plurality of first heating elements 811 made of a rectangular plate-shaped far-red ceramic heater that radiates far infrared rays are axially spaced at predetermined intervals across both axial ends of the rubber roll 3. It is comprised by arranging along. The plurality of first heating elements 811 are applied with voltages from individual power sources so that they can generate heat independently. The first heating element 811 is supported by a rod-like first support member 812 extending along the axial direction of the rubber roll 3, and on a virtual plane (horizontal plane) S ₀ including the rotation axis of the rubber roll 3 and the rotation axis of the mat roll 4. die 2 side region arranged, namely in the vertically upper side of the virtual plane S _0, is arranged opposite to the outer peripheral surface of the rubber roll 3 against. In addition, the angle θ ₁ formed by the virtual plane S ₁ including the center of the first heating element 811 constituting the first heating element group 81 and the rotation axis of the rubber roll 3 and the virtual plane S ₀ is ₀ to 70 °. Set to range.

In the second heating element group 82, a plurality of second heating elements 821 made of a rectangular plate-shaped far-red ceramic heater that radiates far infrared rays are axially spaced from each other at both ends in the axial direction of the rubber roll 3. It is comprised by arranging along. The plurality of second heating elements 821 are applied with voltages from individual power sources so that they can generate heat independently. The second heating element 821 is supported by a rod-like second support member 822 extending along the axial direction of the rubber roll 3, and has a virtual plane (horizontal plane) S ₀ including the rotation axis of the rubber roll 3 and the rotation axis of the mat roll 4. die 2 side region arranged, namely in the vertically upper side of the virtual plane S _0, is arranged opposite to the outer peripheral surface of the rubber roll 3 against. The center of the second heating element 821 constituting the second heating element group 82, and a virtual plane _{S 2} containing the rotation axis of the rubber roll 3, the angle theta ₂ formed by the virtual plane _{S 0} is the 20 to 90 ° Set to range. The angle θ ₂ is set larger than the angle θ ₁ .

  Further, in the first heating unit 8 configured to include the first heating element group 81 and the second heating element group 82, the first heating element 811 and the second heating element 821 connect the first heating unit 8 to the rubber roll 3. When viewed in the direction from the first heating element group 81 toward the second heating element group 82 with respect to the circumferential direction, the second heating element 821 is arranged so that it can be seen from the gap between adjacent first heating elements 811. .

The second heating unit 9 is a rectangular plate-like planar heater having the same size and shape as the outer shape of the rubber roll 3 viewed from the vertical direction. In the present embodiment, the second heating unit 9 includes a plurality of rectangular plate-shaped far-red ceramic heaters that radiate far-infrared rays arranged in a matrix. The second heating section 9, a region on the side opposite to the side of the region which the die 2 is arranged with respect to a virtual plane (horizontal plane) S ₀ including the rotation axis of the rotary shaft and matte roll 4 of the rubber roll 3, ie virtual In the region on the lower side in the vertical direction than the plane S _0, it is provided to face the rubber roll 3. In the present embodiment, the second heating unit 9 is provided directly below the rubber roll 3 in the vertical direction.

  In the resin film manufacturing apparatus 100 including the heating apparatus 10 configured as described above, the resin film manufacturing apparatus 100 is provided to face the outer peripheral surface of the rubber roll 3 in each of the region on the side where the die 2 is disposed and the region on the opposite side. Since the outer peripheral surface of the rubber roll 3 can be sufficiently heated by the first heating unit 8 and the second heating unit 9 to be generated, it is possible to suppress the occurrence of a non-uniform temperature portion in the axial direction on the outer peripheral surface of the rubber roll 3. can do. Therefore, the resin film manufacturing apparatus 100 suppresses generation | occurrence | production in the width direction of the resin film corresponding to the axial direction of the rubber roll 3, and suppresses the generation | occurrence | production of the streak-like defect part extended in the flow direction of a resin film, and improves quality. Can be made.

  Furthermore, the 1st heating part 8 with which the heating apparatus 10 is provided is the 1st heating element group which consists of the several 1st heating element 811 arranged at predetermined intervals along this axial direction over the whole axial direction of the rubber roll 3. As shown in FIG. 81 and a second heating element group 82 including a plurality of second heating elements 821. Thus, the heating control in the axial direction on the outer peripheral surface of the rubber roll 3 can be performed with high accuracy independently by the plurality of rows of the first heating elements 811 and the second heating elements 821 arranged in the axial direction. It is possible to more effectively suppress the occurrence of a non-uniform temperature portion in the axial direction on the outer peripheral surface 3.

  Returning to FIG. 1, in the resin film manufacturing apparatus 100, a mirror roll 5 is provided on the opposite side of the mat roll 4 from the rubber roll 3. The mirror surface roll 5 is made of a cylindrical member having the same outer diameter as the rubber roll 3 and the mat roll 4, and the rotation axis is arranged on the same horizontal plane as the rotation axes of the rubber roll 3 and the mat roll 4. The mirror roll 5 is a metal roll formed in the same manner as the mat roll 4, and the outer surface is mirror-finished.

  The film-like resin is wound around the outer peripheral surface of the lower side of the mat roll 4 by almost a half turn, and then wound around the outer surface of the mirror roll 5 by about 1/4 turn, and is separated at the upper part in the vertical direction of the mirror roll 5. Then, it is taken up by the take-up roll 6 in the horizontal direction.

  In order to cool the film-like resin more slowly, a plurality of cooling rolls are provided between the mirror roll 5 and the take-up roll 6, and the film-like resin is sequentially applied to the next cooling roll from the mirror roll 5. May be wound.

  The surface (outer peripheral surface) temperature of each of the mirror roll 5 and each of the cooling rolls after the mirror roll 5 may be set to any surface temperature, and is not particularly limited, but is usually set to the thermal deformation temperature (Th) of the thermoplastic resin. On the other hand, about ± 15 ° C. is preferable.

  The take-up roll 6 includes an upper roll 6a and a lower roll 6b which are a pair of rolls. Examples of the upper roll 6a and the lower roll 6b include a rubber roll and a metal roll. The lower roll 6b is connected to rotation driving means such as an electric motor, and the upper roll 6a is rotatably arranged so as to be in contact with the lower roll 6b, and the upper roll 6a is also rotated by the rotation of the lower roll 6b. It is configured. Therefore, the upper roll 6a and the lower roll 6b rotate at the same peripheral speed. As long as the peripheral speeds of the upper roll 6a and the lower roll 6b are the same, the configuration opposite to the above configuration, that is, the upper roll 6a is connected to the rotation driving means, and the lower roll 6b is in contact with the upper roll 6a. The upper roll 6a and the lower roll 6b may both be connected to the rotation driving means.

  The resin film as a product taken up by the take-up roll 6 preferably has a thickness of 30 to 300 μm. On the other hand, if the thickness is less than 30 μm, the above-described roll configuration cannot stably obtain a resin film, and if it exceeds 300 μm, it is difficult to handle as a film. The thickness of the resin film can be adjusted by the thickness of the film-like resin extruded from the die 2, the contact pressure between the rubber roll 3 and the mat roll 4, and the length of the nip portion.

  In addition, the haze of the resin film is usually in the range of 20 to 100, preferably 40 to 95, more preferably 60 to 90. The haze of the resin film can be measured using, for example, a haze meter HM-150 (manufactured by Murakami Color Research Laboratory Co., Ltd.).

  Since the resin film has an uneven shape on the surface and has a function of scattering light, for example, a liquid crystal cell combined with an optical disk or a polarizing plate, a retardation film, a diffusion film, a brightness enhancement film, etc., an automobile The present invention can be applied to interior films, lighting films, building material films, and the like, but the present invention is not limited to these applications.

  FIG. 4 is a perspective view showing a configuration of a resin film manufacturing apparatus 200 according to the second embodiment of the present invention. The resin film manufacturing apparatus 200 is similar to the resin film manufacturing apparatus 100 of the first embodiment described above, and corresponding portions are denoted by the same reference numerals and description thereof is omitted. The resin film manufacturing apparatus 200 is configured in the same manner as the resin film manufacturing apparatus 100 except that the configuration of the first heating unit 202 provided in the heating device 201 is different from the first heating unit 8 provided in the heating device 10 described above.

The first heating unit 202 provided in the heating device 201 of the resin film manufacturing apparatus 200 includes a plurality of first heating elements 2021 made of a rectangular plate-shaped far-red ceramic heater that emits far-infrared rays, between both ends in the axial direction of the rubber roll 3. It is composed by arranging in a zigzag pattern. The plurality of first heating elements 2021 are applied with voltages from individual power sources so that they can generate heat independently. The first heating element 2021 is supported by a rod-like first support member 2022 extending along the axial direction of the rubber roll 3, and has a virtual plane (horizontal plane) S ₀ including the rotation axis of the rubber roll 3 and the rotation axis of the mat roll 4. die 2 side region arranged, namely in the vertically upper side of the virtual plane S _0, is arranged opposite to the outer peripheral surface of the rubber roll 3 against. When viewed from the circumferential direction of the rubber roll 3, the plurality of first heating elements 2021 are arranged so as to partially overlap each other adjacent to each other in the axial direction. The angle θ ₁ formed by the virtual plane S ₁ including the center of the first heating element 2021 constituting the first heating unit 202 and the rotation axis of the rubber roll 3 and the virtual plane S ₀ is in the range of 0 to 90 °. Set to

  In the heating device 201 including the first heating unit 202 configured as described above, when viewed from the circumferential direction of the rubber roll 3, a plurality of second devices arranged so as to partially overlap each other adjacent to each other in the axial direction. Since the outer peripheral surface of the rubber roll 3 is heated by the far infrared rays radiated from the one heating element 2021, it is possible to suppress the occurrence of a non-uniform temperature portion in the axial direction on the outer peripheral surface of the rubber roll 3. Therefore, the resin film manufacturing apparatus 200 generates unevenness in the width direction of the resin film corresponding to the axial direction of the rubber roll 3, and suppresses the generation of streak defect portions extending in the flow direction of the resin film, thereby improving the quality. Can be made.

  FIG. 5 is a perspective view showing a configuration of a resin film manufacturing apparatus 300 according to the third embodiment of the present invention. The resin film manufacturing apparatus 300 is similar to the resin film manufacturing apparatus 100 of the first embodiment described above, and corresponding portions are denoted by the same reference numerals and description thereof is omitted. The resin film manufacturing apparatus 300 is configured in the same manner as the resin film manufacturing apparatus 100 except that the configuration of the first heating unit 302 provided in the heating device 301 is different from the first heating unit 8 provided in the heating device 10 described above.

The first heating unit 302 included in the heating device 301 of the resin film manufacturing apparatus 300 includes a plurality of first heating elements 3021 made of a rectangular plate-shaped far-red ceramic heater that radiates far infrared rays between both ends in the axial direction of the rubber roll 3. It is comprised by arranging at predetermined intervals. The plurality of first heating elements 3021 are applied with voltages from individual power sources so that they can generate heat independently. The first heating element 3021 is supported by a rod-shaped first support member 3022 extending along the axial direction of the rubber roll 3, and has a virtual plane (horizontal plane) S ₀ including the rotation axis of the rubber roll 3 and the rotation axis of the mat roll 4. die 2 side region arranged, namely in the vertically upper side of the virtual plane S _0, is arranged opposite to the outer peripheral surface of the rubber roll 3 against. The angle θ ₁ formed by the virtual plane S ₁ including the center of the first heating element 3021 constituting the first heating unit 302 and the rotation axis of the rubber roll 3 and the virtual plane S ₀ is in the range of 0 to 90 °. Set to

  In the heating apparatus 301 including the first heating unit 302 configured as described above, far infrared rays radiated from a plurality of first heating elements 3021 arranged at predetermined intervals across both axial ends of the rubber roll 3. Thus, since the outer peripheral surface of the rubber roll 3 is heated, it is possible to suppress the occurrence of a non-uniform temperature portion in the axial direction on the outer peripheral surface of the rubber roll 3. Therefore, the resin film manufacturing apparatus 300 improves the quality by suppressing the generation of streak-like defect portions that occur unevenly in the width direction of the resin film corresponding to the axial direction of the rubber roll 3 and extend in the flow direction of the resin film. Can be made.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, an Example is one embodiment of this invention and does not limit this invention.

Example 1
The resin film was manufactured using the resin film manufacturing apparatus 100 shown in FIG. 1 provided with the 1st heating part 8 which has the heating element group of 2 rows in the circumferential direction of the rubber roll 3. As shown in FIG.

<Thermoplastic resin>
As the thermoplastic resin, polycarbonate (Caliber 301-10, manufactured by Sumitomo Dow Co., Ltd.) was used.

<Extruder 1>
As the extruder 1, a uniaxial extruder (manufactured by Toshiba Machine Co., Ltd.) having a cylinder diameter of 115 mm was used.

<Die 2>
A T-die having a set temperature of 270 ° C. and a total width of 1900 mm was used as the die 2 and the film-like resin was discharged at a discharge rate of 330 kg / h.

<Rubber roll 3>
As the rubber roll 3, a silicone rubber roll having an outer diameter of 400 mm, an axial length of 1850 mm, and a durometer hardness of A70 was used.

<Mat roll 4>
As the mat roll 4, a stainless steel metal roll (drilled roll) having an outer diameter of 400 mm, an axial length of 1850 mm, and an irregular shape having an arithmetic average surface roughness (Ra) of 2.7 μm formed by blasting was used. . The rotation axis of the rubber roll 3 and the rotation axis of the mat roll 4 were arranged on the same horizontal plane.

<Mirror surface roll 5>
As the mirror roll 5, a mirror-finished stainless steel metal roll (drilled roll) having an outer diameter of 400 mm and an axial length of 1850 mm was used.

<Take-up roll 6>
As the upper roll 6a and the lower roll 6b, a silicone rubber roll having an outer diameter of 300 mm and an axial length of 1850 mm was used.

<Heating device 10>
[First heating unit 8]
As the first heating element 811 constituting the first heating element group 81 and the second heating element 821 constituting the second heating element group 82, a square plate-shaped far-red ceramic heater (S-IIII type, having a side of 122 mm) Sakaguchi Electric Heat Co., Ltd.) was used.

In the first heating element group 81, 13 first heating elements 811 have a pitch width (a distance between the centers of the first heating elements 811 adjacent to each other in the axial direction of the rubber roll 3) of 135 mm in the axial direction of the rubber roll 3. Composed by arranging along. The first heating element group 81 is disposed vertically upper side of the virtual plane S ₀ including the rotation axis of the rotary shaft and matte roll 4 of rubber roll 3. Further, the angle θ ₁ formed by the virtual plane S ₁ including the center of the first heating element 811 constituting the first heating element group 81 and the rotation axis of the rubber roll 3 and the virtual plane S ₀ was set to 45 °. .

In the second heating element group 82, the 14 second heating elements 821 have a pitch width (a distance between the centers of the second heating elements 821 adjacent to each other in the axial direction of the rubber roll 3) of 135 mm in the axial direction of the rubber roll 3. Composed by arranging along. The second heating element group 82 is arranged on the upper side in the vertical direction with respect to the virtual plane S ₀ including the rotation axis of the rubber roll 3 and the rotation axis of the mat roll 4. The center of the second heating element 821 constituting the second heating element group 82, and a virtual plane S ₂ containing the rotation axis of the rubber roll 3, the angle theta ₂ formed by the virtual plane S ₀ was set to 77 ° .

[Second heating unit 9]
A square plate-shaped far red ceramic heater (S-III type, manufactured by Sakaguchi Electric Heat Co., Ltd.) having a side of 122 mm is arranged in a matrix, and a rectangular shape of 450 mm × 1900 mm corresponding to the outer dimensions of the rubber roll 3 viewed from the vertical direction. The surface heater was shaped. This planar heater was arranged directly below the rubber roll 3 so as to face the rubber roll 3.

<Surface temperature of each roll>
The surface temperature of the mat roll 4 was set to 130 ° C., and the surface temperature of the mirror roll 5 was set to 135 ° C. The core temperature of the rubber roll 3 was set to 40 ° C. The surface temperature of the rubber roll 3 was controlled by heating the outer peripheral surface with the heating device 10 and was 150 ° C. as a result of controlling the haze in the width direction of the resin film corresponding to the axial direction to be uniform.

  A resin film was manufactured using the resin film manufacturing apparatus 100 configured as described above. The produced resin film had a thickness of 130 μm and a width dimension of 1700 mm.

(Example 2)
The resin film was manufactured using the resin film manufacturing apparatus 200 shown in FIG. 4 provided with the 1st heating part 202 with which the several heat generating body arranged in zigzag form in the axial direction of the rubber roll 3. FIG. The resin film manufacturing apparatus 200 in Example 2 is the same as Example 1 except that the configuration of the first heating unit 202 is different from that of the first heating unit 8 in Example 1.

[First heating unit 202]
As the first heating element 2021 constituting the first heating unit 202, a square plate-shaped far-red ceramic heater (S-III type, manufactured by Sakaguchi Electric Heat Co., Ltd.) having a side of 122 mm was used. The first heating unit 202 is configured such that, when viewed from the circumferential direction of the rubber roll 3, the 13 first heating elements 2021 partially overlap with each other adjacent to each other in the axial direction of the rubber roll 3 (overlap width dimension: 34 mm) and arranged in a zigzag pattern in the axial direction of the rubber roll 3. The first heating unit 202 is disposed vertically upward of the virtual plane S ₀ including the rotation axis of the rotary shaft and matte roll 4 of rubber roll 3. Further, the angle θ ₁ formed by the virtual plane S ₁ including the center of the first heating element 2021 constituting the first heating unit 202 and the rotation axis of the rubber roll 3 and the virtual plane S ₀ was set to 45 °.

  A resin film was manufactured using the resin film manufacturing apparatus 200 configured as described above. The produced resin film had a thickness of 130 μm and a width dimension of 1700 mm.

(Example 3)
The resin film was manufactured using the resin film manufacturing apparatus 300 shown in FIG. 5 provided with the 1st heating part 302 in which several heat generating bodies are arranged along the axial direction of the rubber roll 3. As shown in FIG. The resin film manufacturing apparatus 300 in Example 3 is the same as Example 1 except that the configuration of the first heating unit 302 is different from the first heating unit 8 in Example 1.

[First heating unit 302]
As the first heating element 3021 constituting the first heating unit 302, a square plate-shaped far-red ceramic heater (S-III type, manufactured by Sakaguchi Electric Heat Co., Ltd.) having a side of 122 mm was used. In the first heating unit 302, 13 first heating elements 3021 have a pitch width (a distance between the centers of the first heating elements 3021 adjacent to each other in the axial direction of the rubber roll 3) of 135 mm along the axial direction of the rubber roll 3. Configured. The first heating unit 302 is arranged on the upper side in the vertical direction from the virtual plane S ₀ including the rotation axis of the rubber roll 3 and the rotation axis of the mat roll 4. The angle θ ₁ formed by the virtual plane S ₁ including the center of the first heating element 3021 constituting the first heating unit 302 and the rotation axis of the rubber roll 3 and the virtual plane S ₀ was set to 45 °.

  A resin film was manufactured using the resin film manufacturing apparatus 300 configured as described above. The produced resin film had a thickness of 130 μm and a width dimension of 1700 mm.

(Comparative Example 1)
Example 1 was performed except that the first heating unit 8 was not provided.

<Evaluation method>
The optical properties of the obtained resin film were evaluated by measuring the haze of the resin film. The sample haze was measured using a haze meter HM-150 (Murakami Color Research Laboratory Co., Ltd.). For the evaluation sample, two rounds (length: 3000 mm) wound around a roll were sampled and measured at 15 points at equal intervals in the width direction, and this was measured as 15 measurement lines at equal intervals in the flow direction. did. Therefore, there are a total of 225 measurement positions.

  Calculate the arithmetic average value, the maximum value, the minimum value, the difference between the maximum value and the minimum value (maximum value-minimum value), and the standard deviation from the haze of 15 points for each measurement column, and calculate the arithmetic average for the 15 columns The arithmetic mean value was calculated for each of the value, maximum value, minimum value, difference between the maximum value and the minimum value (maximum value−minimum value), and standard deviation. The evaluation results are shown in Table 1.

  The resin film samples produced in Examples 1 to 3 had smaller arithmetic mean values of standard deviation than the resin film samples produced in Comparative Example 1. This indicates that the haze variation in the flow direction and the width direction of the resin film is smaller in Examples 1 to 3 than in Comparative Example 1.

DESCRIPTION OF SYMBOLS 1 Extruder 2 Die 3 Rubber roll 4 Mat roll 5 Mirror surface roll 6 Take-up roll 7 Energizing device 8, 202, 302 1st heating part 9 2nd heating part 10, 201, 301 Heating apparatus 11 Filtration apparatus 81 1st heating element Group 82 Second heating element group 100, 200, 300 Resin film manufacturing apparatus 811, 2021, 3021 First heating element 821 Second heating element

Claims (7)

A resin film manufacturing apparatus for manufacturing a resin film made of a thermoplastic resin by a melt extrusion molding method,
A film forming means for forming a film by extruding a molten thermoplastic resin into a film;
It consists of a first roll and a second roll, the rotation axis of the first roll and the rotation axis of the second roll are parallel, and the outer peripheral surface of the first roll and the outer peripheral surface of the second roll are in contact with each other. The film-shaped thermoplastic resin extruded from the film-forming means is sandwiched between the outer peripheral surface of the first roll and the outer peripheral surface of the second roll, thereby forming a film-shaped thermoplastic resin. Molding means for molding the surface shape of the thermoplastic resin into a predetermined shape;
A heating means for heating the outer peripheral surface of the first roll, in a region on the side where the film forming means is disposed with respect to a virtual plane including the rotation axis of the first roll and the rotation axis of the second roll The first heating unit provided to face the first roll and the region opposite to the side on which the film forming means is disposed with respect to the virtual plane are provided to face the first roll. A resin film manufacturing apparatus comprising: a heating unit including a second heating unit.   The first heating unit includes a heating element group including a plurality of heating elements arranged at predetermined intervals along the axial direction over the entire axial direction of the first roll. The apparatus for producing a resin film according to claim 1.   The plurality of heating elements in the heating element group are arranged in a staggered manner so that a part of the heating elements adjacent to each other in the axial direction overlap when viewed from the circumferential direction of the first roll. The resin film manufacturing apparatus according to claim 2.   The resin film manufacturing apparatus according to claim 2, wherein a plurality of rows of the heating element groups are formed in the first heating unit in a circumferential direction of the first roll.   5. The resin film manufacturing apparatus according to claim 1, wherein the second heating unit is provided directly below the first roll in a direction perpendicular to the virtual plane. A method for producing a resin film made of a thermoplastic resin by a melt extrusion molding method,
A film forming step of forming a film by extruding a molten thermoplastic resin into a film by a film forming means;
A molding step of molding a film-like thermoplastic resin extruded from the film-forming means by molding means comprising a first roll and a second roll, wherein the outer peripheral surface of the first roll and the outer periphery of the second roll Including a molding step of molding the surface shape of the film-like thermoplastic resin into a predetermined shape by sandwiching with the surface,
In the molding step, the outer peripheral surface of the first roll is heated by a heating means,
The heating means is provided to face the first roll in a region on the side where the film forming means is disposed with respect to a virtual plane including the rotation axis of the first roll and the rotation axis of the second roll. It has a 1st heating part and the 2nd heating part provided facing the 1st roll in the field opposite to the side where the film forming means is arranged to the virtual plane, A method for producing a resin film. A resin film with optical properties,
A plurality of points are measured at equal intervals in the width direction at the time of manufacture, and the standard deviation of haze is 2.0 or less when this is measured as a single measurement row and a plurality of rows are measured at equal intervals in the flow direction. Resin film.

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