Apparatus for producing film, and, suction device

Abstract

To provide a producing apparatus of a film capable of suppressing for a liquid or a solid generated due to a prescribed component that vaporizes at a low temperature than a film-constituting resin to deposit in a suction device, and, a suction device.SOLUTION: A film producing apparatus includes an exhaust member 4 provided at both ends in the width direction (TD) with exhaust ports 11 capable of discharging predetermined components that gasify at a temperature lower than that of the film-forming resin, and an inflow region 5 extending in the width direction (TD) to allow the predetermined components to flow into the exhaust member 4. The exhaust passage 12 communicating with the exhaust port 11 is configured to include a planar rear surface 12a, a planar top surface 12d, a planar bottom surface 12e, a first connecting surface 13a connecting the rear surface 12a and the top surface 12d so that the connection site of the rear surface 12a and the top surface 12d forms an obtuse angle when viewed from the exhaust passage 12, and a second connecting surface 13b connecting the rear surface 12a and the bottom surface 12e so that the connection site between the rear surface 12a and the bottom surface 12e forms an obtuse angle when viewed from the exhaust passage 12.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a film manufacturing apparatus and a suction device. [Background technology]

[0002] 12, some conventional devices for producing resin films include a die 201 having a discharge port 206 that discharges a sheet material 207 containing a molding resin for forming a film and a low-melting-point resin having a melting point lower than that of the molding resin, a casting device 202 that cools and solidifies the sheet material 207 discharged from the discharge port 206 while conveying it, and a decompression chamber 203 that is arranged upstream of the discharge port 206 in the sheet conveyance direction, covers the space between the sheet material 207 and the casting device 202, and draws in air to form a decompressed space (see, for example, Patent Document 1). The decompression chamber 203 is used to reduce the pressure of the atmosphere on the back side of the sheet material 207, causing the sheet material 207 to adhere closely to the casting device 202.

[0003] The apparatus described in Patent Document 1 employs a method in which sheet material 207 is discharged from a discharge port 206 toward a casting device 202, and air is sucked from the space through suction ports 208 of suction pipes 210 arranged outside both ends of the sheet material 207 in the sheet width direction, thereby causing the sheet material 207 to adhere to the casting device 202, and the sheet material 207 is cooled and solidified while being transported by the casting device 202. Note that the resin film is completed as a microporous film by undergoing a process of stretching the sheet material 207 by a device not shown in the figure at the destination of the transport of the sheet material 207 by the casting device 202 and a process of extracting the low-melting point resin. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2023-020052 Summary of the Invention [Problem to be solved by the invention]

[0005] With the recent increase in resin film production, there is a strong demand for increasing the discharge rate of sheet material and extending the continuous film-forming time. On the other hand, increasing the discharge rate of sheet material and extending the continuous film-forming time also increases the chances of liquefaction of gases derived from low-melting-point resins, diluents, and additives in the sheet material (hereinafter, these liquefied substances are also referred to as "droplets"). If these droplets accumulate and scatter in the suction port or decompression chamber, they can cause defects in the resin sheet or film or tear the resin sheet or film.

[0006] The present invention has been made in consideration of the above-mentioned circumstances, and its purpose is to provide a film manufacturing apparatus and a suction device that can prevent liquids and solids generated due to certain components that gasify at a lower temperature than the film-constituting resin from accumulating in the suction device. [Means for solving the problem]

[0007] The film manufacturing apparatus of the present disclosure that solves the above-mentioned problems is a film manufacturing apparatus that manufactures a film using a resin mixture obtained by mixing a film-constituting resin and a predetermined component that gasifies at a lower temperature than the film-constituting resin, and includes an exhaust member having exhaust ports at both ends in the width direction (TD) for discharging the predetermined component, and an inflow area that extends in the width direction (TD) and allows the predetermined component to flow into the exhaust member, the exhaust member being formed so that the surface facing the inflow area is open in the width direction and having an exhaust path that communicates with the exhaust port, the exhaust path including a planar rear surface, a planar top surface located above, a planar bottom surface located below, a first connecting surface that connects the rear surface and the top surface so that a connection portion between the rear surface and the top surface forms an obtuse angle when viewed from the exhaust path, and a second connecting surface that connects the rear surface and the bottom surface so that a connection portion between the rear surface and the bottom surface forms an obtuse angle when viewed from the exhaust path.

[0008] In addition, in the film manufacturing apparatus of the present disclosure, the exhaust channel includes a first planar side surface located at one end side in the width direction (TD), a second planar side surface located at the other end side in the width direction (TD), a third connecting surface connecting the first side surface and the top surface such that a connection portion between the first side surface and the top surface forms an obtuse angle when viewed from the exhaust channel, a fourth connecting surface connecting the second side surface and the top surface such that a connection portion between the second side surface and the top surface forms an obtuse angle when viewed from the exhaust channel, and a fifth connecting surface connecting the first side surface and the bottom surface such that a connection portion between the first side surface and the bottom surface forms an obtuse angle when viewed from the exhaust channel. It is preferable that the exhaust passage further includes a fifth connecting surface that connects the first side surface and the lower surface as described above, a sixth connecting surface that connects the second side surface and the lower surface so that a connection portion between the second side surface and the lower surface forms an obtuse angle when viewed from the exhaust path, a seventh connecting surface that connects the rear surface and the first side surface so that a connection portion between the rear surface and the first side surface forms an obtuse angle when viewed from the exhaust path, and an eighth connecting surface that connects the rear surface and the second side surface so that a connection portion between the rear surface and the first side surface forms an obtuse angle when viewed from the exhaust path.

[0009] Furthermore, in the film manufacturing apparatus of the present disclosure, it is preferable that the first connecting surface, the second connecting surface, the third connecting surface, the fourth connecting surface, the fifth connecting surface, the sixth connecting surface, the seventh connecting surface, and the eighth connecting surface are each formed in a curved shape that is convex toward the outside of the exhaust member.

[0010] In the film manufacturing apparatus of the present disclosure, it is preferable that the first connecting surface and the second connecting surface have a radius of curvature of 2 mm or more.

[0011] In addition, in the film manufacturing device of the present disclosure, it is preferable that the lower side of the open end surface of the exhaust member is cut out to form the inflow area.

[0012] In addition, in the film manufacturing apparatus of the present disclosure, it is preferable that the exhaust path has a pair of flat side surfaces on which the exhaust outlet is provided, and that the ratio S1 / S2 of the opening area S1 of the exhaust outlet to the area S2 of the side surfaces is 1 or less.

[0013] Furthermore, in the film manufacturing apparatus of the present disclosure, it is preferable that the exhaust path has a pair of flat side surfaces on which the exhaust outlet is provided, and that the exhaust outlet is provided at a position whose linear distance from the rear surface is 0 mm or more and 10 mm or less and whose linear distance from the bottom surface is 0 mm or more and 10 mm or less.

[0014] In the film manufacturing apparatus of the present disclosure, the second connecting surface is preferably inclined downward from the apex at the center of the width direction (TD) toward the exhaust port.

[0015] In addition, the film manufacturing apparatus of the present disclosure further comprises a die having a discharge port for discharging the resin mixture, a casting device that cools and solidifies the resin mixture discharged from the die while transporting it, and a decompression chamber that covers the decompressed space between the resin mixture discharged from the die and the casting device, and is located upstream of the discharge port in the transport direction (MD) of the resin mixture, and sucks out the air inside to bring the resin mixture into close contact with the casting device, and it is preferable that the film manufacturing apparatus is configured to suck in at least one of droplets and solids generated by the specified components and attached to the inside of the decompression chamber on the upstream side in the transport direction of the decompression chamber through the inflow area.

[0016] The suction device of the present disclosure that solves the above-mentioned problems is a suction device attached to a resin molding machine that molds a target resin part using a resin mixture formed by heating the molding resin of the target resin part and a predetermined component that gasifies at a lower temperature than the molding resin, and is equipped with an exhaust member having an exhaust port for discharging the predetermined component, and an inlet region for allowing the predetermined component to flow into the exhaust member, wherein the exhaust member is recessed so that the surface facing the inlet region is open and has an exhaust space that communicates with the exhaust port, and the exhaust space includes a planar rear surface, a planar top surface located on the upper side, a planar bottom surface located on the lower side, a first connecting surface that connects the rear surface and the top surface so that the connection portion between the rear surface and the top surface forms an obtuse angle when viewed from the exhaust space, and a second connecting surface that connects the rear surface and the bottom surface so that the connection portion between the rear surface and the bottom surface forms an obtuse angle when viewed from the exhaust space. [Effects of the Invention]

[0017] According to the film manufacturing apparatus and suction device of the present disclosure, the exhaust member is formed so that the inner surface of the exhaust member has obtuse angles rather than sharp corners, thereby preventing liquids and solids generated by certain components that gasify at a lower temperature than the film-constituting resin from accumulating in the suction device. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a schematic cross-sectional view of a film manufacturing apparatus including a suction device according to one embodiment of the present invention (however, a resin molding machine for manufacturing the film is not shown). [Figure 2] FIG. 2 is a schematic cross-sectional view of an exhaust member including an inlet region. [Figure 3] FIG. 3 is a diagram for explaining the exhaust port, and is a schematic side view of the exhaust member. [Figure 4] FIG. 4 is a schematic front view of the exhaust member. [Figure 5] FIG. 5 is a schematic perspective view of the exhaust member. [Figure 6] FIG. 6 is a diagram for explaining the manner in which droplets are discharged from inside the decompression chamber. [Figure 7] FIG. 7 is a diagram for explaining the flow of droplets inside the exhaust member. [Figure 8] FIG. 8 is a diagram for explaining the inflow region, and corresponds to the schematic bottom view of FIG. [Figure 9] FIG. 9 is a diagram for explaining the inflow region, and corresponds to FIG. 8 (however, protrusions are not shown). [Figure 10] FIG. 10 is a diagram for explaining a modified example of the exhaust member, and corresponds to FIG. 2. In FIG. [Figure 11] FIG. 11 is a perspective view showing another embodiment of the suction device of the present invention. [Figure 12] FIG. 12 is a schematic diagram showing an example of a conventional apparatus for producing a resin film. DETAILED DESCRIPTION OF THE INVENTION

[0019] [Terminology] The meaning of each term in the present invention will be explained. As will be described later, the "sheet" is a thin film formed by preparing a resin mixture containing a resin and a component that plasticizes the resin. The term "film" refers to a resin that is thinner than a "sheet" and is formed by at least stretching the resin mixture after preparing the resin mixture. As a guideline for the difference between a "sheet" and a "film," a "sheet" generally refers to something that is 250 μm (or 200 μm) or more in thickness or that contains the plasticizing component, while a "film" can refer to something that is less than 250 μm (or 200 μm) in thickness or a sheet from which the plasticizing component has been removed.

[0020] The term "film-constituting resin" refers to one of the resins that constitute the film. Examples of film-constituting resins include polyolefin resins such as polyethylene, polypropylene, polystyrene, and polymethylpentene.

[0021] The "predetermined component that vaporizes at a lower temperature than the film-constituting resin" refers to a component that has a lower boiling point or sublimation point than the film-constituting resin. Examples of the predetermined component include a diluent and an antioxidant. The diluent may be, for example, liquid paraffin (LP), and is not particularly limited as long as it can be mixed or dissolved in the polyolefin resin (film-constituting resin). Materials that are miscible with the polyolefin in a melt-kneaded state but are solid at room temperature may also be used as diluents. Examples of such solid diluents include stearyl alcohol, ceryl alcohol, and paraffin wax. The antioxidant is a compound used to suppress oxidation of the film-constituting resin, and is not particularly limited as long as it is a substance that can be mixed or dissolved in, for example, the polyolefin resin (film-constituting resin).

[0022] The "resin mixture" refers to a mixture containing the film-constituting resin and the predetermined components. Examples of the resin mixture include a polyolefin solution prepared by mixing the film-constituting resin and the predetermined components and then heating and melting them. The process for uniformly melt-kneading the resin mixture is not particularly limited, but examples include a calendar, various mixers, and an extruder with a screw. Hereinafter, the resin mixture will also be referred to as a sheet material.

[0023] "Transverse direction (TD)" refers to the direction coincident with the width of the sheet material. The "sheet conveyance direction (MD)" refers to the direction in which the casting device conveys the sheet material, based on the landing point of the sheet material on the casting device 2 (casting surface) described below. The destination of the sheet material is the downstream side, and the landing point side is the upstream side. Therefore, the upstream end in the sheet conveyance direction is the landing point, but in the following explanation, for convenience, the side upstream of the landing point in the rotation direction of the casting device 2 will also be described as the upstream side of this "sheet conveyance direction."

[0024] <Embodiment> The present invention will be specifically described below by way of embodiments with reference to the drawings. However, the present invention is not limited to the following embodiments and can be modified, improved, etc. as appropriate. In addition, the material, shape, size, number, location, etc. of each component in the following embodiments are arbitrary and not limited as long as they can achieve the present invention.

[0025] [Schematic configuration of film manufacturing equipment] The schematic configuration of a film production apparatus 100 according to one embodiment of the present invention will be described below with reference to Figures 1 to 8. The film production apparatus 100 includes a die 1, a casting device 2, and a suction device 101. The suction device 101 includes a decompression chamber 3, an exhaust member 4, and an inlet region 5.

[0026] The film manufacturing apparatus 100 is provided with a die 1 that discharges a sheet material 7 from vertically above to vertically below, and a casting device 2 is provided vertically below the die 1. A decompression chamber 3 is located vertically between the die 1 and the casting device 2, and an exhaust member 4 is located upstream of the decompression chamber 3 in the sheet conveyance direction. A cover 9 is attached to the exhaust member 4 downstream in the sheet conveyance direction, and the cover 9 is located between the decompression chamber 3 and the exhaust member 4 in the sheet conveyance direction. An inlet region 5 is located between the exhaust member 4 and the cover 9 in the sheet conveyance direction, and the inlet region 5 is located vertically below the exhaust member 4. The configurations of the die 1, casting device 2, decompression chamber 3, and exhaust member 4 that constitute the film manufacturing apparatus 100 will be described below.

[0027] (Socket 1) The die 1 is a die for a device such as a resin molding machine or an extruder, and has a discharge port 6 for discharging a sheet material 7 .

[0028] (Cast device 2) The casting device 2 is a device that conveys the sheet material 7 discharged from the discharge port 6 of the die 1 downstream in the sheet conveyance direction while cooling and solidifying it by tightly contacting the sheet material 7. The casting device 2 is configured such that the central axis connecting the centers of two circular faces on the outer circumferential surface of a roll-shaped device (hereinafter also referred to as "roll") is rotatable about an axis parallel to the sheet width direction, and the roll rotates about the central axis, causing the sheet material 7 discharged from the die 1 to rotate and be cast on the outer circumferential surface of the roll as the roll rotates. The form of the casting device 2 is not particularly limited, and it may be, for example, a belt.

[0029] (Decompression Chamber 3) The decompression chamber 3 is a device that covers the space formed between the sheet material 7 and the casting device 2 in the sheet conveyance direction, and reduces the pressure in the space to bring the sheet material 7 into close contact with the casting device 2. The decompression chamber 3 is formed to be larger than the sheet material 7 and smaller than the casting device 2 in the sheet width direction.

[0030] The decompression chamber 3 is fixed to a member (not shown) and is disposed adjacent to the discharge port 6 on the rear side of the discharge port 6, i.e., upstream in the sheet conveying direction of the point where the sheet material 7 lands on the casting surface, so as to cover part of the surface of the casting device 2. The decompression chamber 3 generates a negative pressure region on the rear side of the sheet material 7, i.e., on the side where the sheet material 7 contacts the casting device 2. Openings 8 are provided on both side walls of the decompression chamber 3 in the sheet width direction, and the openings 8 are located outside the width of the sheet material 7, immediately adjacent to the part where the sheet material 7 begins to adhere to the outer peripheral surface of the casting device 2, which is the casting surface. The openings 8 are part of the decompression chamber 3 that sucks air from within the decompression chamber 3.

[0031] A first suction pipe (not shown) extending from a negative pressure generating device (such as a vacuum cleaner) (not shown) is connected to the opening 8. A pressure gauge (not shown) is provided in the first suction pipe, and the degree of vacuum in the vacuum chamber 3 can be controlled to a predetermined value by a control device (not shown), thereby stably adhering the sheet material 7 to the casting device 2. At this time, it is preferable to control the degree of vacuum in the vacuum chamber 3 to a predetermined value depending on the film-forming conditions, such as the viscosity of the sheet material 7, the thickness of the sheet material 7, and the film conveying speed of the casting device 2. The suction pressure relative to atmospheric pressure in the vacuum chamber 3 is determined appropriately.

[0032] Furthermore, the rear surface 3a located upstream in the sheet conveying direction within the decompression chamber 3 is formed to slope downward in the sheet conveying direction from near the lower position of the die 1 toward the inflow region 5. Therefore, droplets d adhering to the rear surface 3a flow along the rear surface 3a to the vicinity of the inflow region 5, and are sucked into the exhaust member 4 via the inflow region 5, as shown in FIG.

[0033] (Exhaust part 4) The exhaust member 4 is a device that discharges droplets d from the decompression chamber 3 to a dust collector (not shown) in order to suppress the accumulation of droplets d within the decompression chamber 3. As shown in FIG. 1 , the exhaust member 4 is located upstream of the decompression chamber 3 in the sheet conveyance direction and is fixed to the decompression chamber 3 so as to be spaced apart from the surface of the casting device 2. As a result, the exhaust member 4 is provided so as to cover part of the surface of the casting device 2 without contacting the casting device 2. The exhaust member 4 is larger than the sheet material 7 and smaller than the casting device 2 in the sheet width direction, and is formed to be approximately equal to the decompression chamber 3.

[0034] 2 and 4, the exhaust member 4 is formed in a roughly box shape, and specifically, is configured so that a rear surface 12a on the upstream side in the sheet conveying direction, a pair of side surfaces 12b and 12c facing each other in the sheet width direction, a top surface 12d on the upper side, and a bottom surface 12e on the lower side form outer surfaces. As shown in FIGS. 2, 6, and 8, a portion of the member forming the bottom surface 12e on the decompression chamber 3 side is cut out in the sheet width direction to form an inlet region 5. Therefore, the surface of the exhaust member 4 facing the inlet region 5 is open in the sheet width direction. This inlet region 5 will be described later.

[0035] If the roughly box-shaped region that is the internal space of the exhaust member 4 is referred to as the exhaust path 12, it can be said that the exhaust member 4 is open so that the surface of the exhaust path 12 on the downstream side in the sheet conveyance direction is exposed. The edges of the pair of side surfaces 12b, 12c and the top surface 12d that surround the exposed surfaces of the exhaust path 12 can be said to form an open end surface 14. A plate-shaped cover 9 is attached to the exhaust member 4 so as to close the opening of the exhaust path 12, i.e., so as to connect the open end surface 14 around the circumferential direction. The rear surface 12a, the side surfaces 12b, 12c, the top surface 12d, and the bottom surface 12e are each formed flat.

[0036] Further, the exhaust path 12 has connecting surfaces 13a to 13h in order to prevent droplets d from remaining in the exhaust path 12 and to form a swirling air current in the exhaust path 12. The connecting surfaces 13a to 13h will be described below with reference to Figs. 4 and 5.

[0037] The connecting surface 13a (first connecting surface) is a surface that connects the rear surface 12a and the top surface 12d over the entire area in the sheet width direction so that a connection portion between the rear surface 12a and the top surface 12d forms an obtuse angle when viewed from the exhaust path 12. The connecting surface 13b (second connecting surface) is a surface that connects the rear surface 12a and the bottom surface 12e over the entire area in the sheet width direction so that a connection portion between the rear surface 12a and the bottom surface 12e forms an obtuse angle when viewed from the exhaust path 12. The connecting surface 13c (third connecting surface) is a surface that connects the side surface 12b and the top surface 12d over the entire area in the sheet conveying direction so that a connection portion between the side surface 12b (first side surface) on one end side in the sheet width direction and the top surface 12d forms an obtuse angle when viewed from the exhaust path 12. The connecting surface 13d (fourth connecting surface) is a surface that connects the side surface 12c (second side surface) on the other end side in the sheet width direction and the top surface 12d over the entire area in the sheet conveying direction so that a connection portion between the side surface 12c (second side surface) and the top surface 12d forms an obtuse angle when viewed from the exhaust path 12. The connecting surface 13e (fifth connecting surface) is a surface that connects the side surface 12b and the bottom surface 12e over the entire area in the sheet conveying direction so that a connection portion between the side surface 12b and the bottom surface 12e forms an obtuse angle when viewed from the exhaust path 12. The connecting surface 13f (sixth connecting surface) is a surface that connects the side surface 12c and the bottom surface 12e over the entire area in the sheet conveying direction so that a connection portion between the side surface 12c and the bottom surface 12e forms an obtuse angle when viewed from the exhaust path 12. Connecting surface 13g (seventh connecting surface) is a surface that connects rear surface 12a and side surface 12b over the entire vertical direction so that the connecting portion between rear surface 12a and side surface 12b forms an obtuse angle when viewed from exhaust path 12. Connecting surface 13h (eighth connecting surface) is a surface that connects rear surface 12a and side surface 12c over the entire vertical direction so that the connecting portion between rear surface 12a and side surface 12c forms an obtuse angle when viewed from exhaust path 12.

[0038] Each of the connecting surfaces 13a to 13h is formed as a curved surface that is convex toward the outside of the exhaust passage 12. In other words, the exhaust member 4 has a so-called R-processed inner corner portion. Therefore, when viewed from the inside of the exhaust passage 12, the connecting surfaces 13a to 13h are formed at an obtuse angle so that no acute corners of 90° or less are formed. As shown in FIG. 4, the lower surface 12e and the connecting surface 13b are formed in a roughly inverted V-shape when viewed from the front, with the center of the sheet width direction as the apex and sloping downward toward both ends, so that when droplets d adhere to the lower surface of the exhaust path 12, the droplets d flow from the center toward either end.

[0039] For the same reason, the lower surface 12e and the connecting surfaces 13e and 13f are each formed with an inclination that decreases from the downstream side in the sheet conveying direction toward the exhaust port 11 on the upstream side in the sheet conveying direction. The curvature radius of the connecting surfaces 13a to 13h is preferably formed to be 2 mm or more. There is no particular upper limit as long as the present invention can be implemented, but from the viewpoint of uniform wind speed distribution, it is more preferable that it be 20 mm or less. Furthermore, the curvature radius of the connecting surfaces 13a to 13h is more preferably formed to match the (curvature) radius of the exhaust port 11 so that the droplets d that have flowed into the exhaust path 12 are smoothly discharged to the dust collector. Note that the lower surface 12e and the connecting surface 13b shown in FIG. 4 are exaggerated for illustrative purposes.

[0040] The exhaust path 12 has side surfaces 12b and 12c each provided with an exhaust port 11 for exhausting droplets d that have flowed (ie, been sucked) into the exhaust path 12 from the inflow region 5 to the outside.

[0041] The position of the exhaust port 11 is appropriately set so that the droplets d that have flowed into the exhaust path 12 from the inflow region 5 are smoothly discharged to the dust collector. Referring to Fig. 3, the open end inside the exhaust port 11 is preferably provided at a position where the linear distance X from the innermost surface 12a is 0 mm or more and 10 mm or less, and the linear distance Y from the lower surface 12e is 0 mm or more and 10 mm or less. From the viewpoint of suppressing retention of the droplets d in the exhaust path 12, it is more preferable that the linear distances X and Y are both 0 mm.

[0042] For the same reason, it is preferable that exhaust port 11 be formed so that the ratio S1 / S2 of the opening area S1 of exhaust port 11 to the area S2 of side surfaces 12b, 12c (S2 includes S1) is not more than 1. Furthermore, from the viewpoint of stabilizing the wind speed distribution, it is more preferable that exhaust port 11 be formed so that the ratio S1 / S2 is not less than 1 / 16 and not more than 1.

[0043] A second suction pipe (not shown) extending from the dust collector is connected to each exhaust port 11. That is, each exhaust port 11 is a part of the exhaust member 4 that sucks air from the exhaust path 12. This allows the air in the decompression chamber 3 to be sucked in through the second suction pipe, and accordingly, the droplets d in the decompression chamber 3 flow from the inflow region 5 into the exhaust path 12 and are discharged to the dust collector via the second suction pipe.

[0044] As shown in FIG. 2, among the components constituting the outer surface of the exhaust member 4, the component constituting the lower surface 12e has a portion on the decompression chamber 3 side cut out in the seat width direction to form the inlet region 5, as described above.

[0045] Among the components constituting the outer surface of the exhaust member 4, the lower end portions of the side surfaces 12b, 12c at both ends in the sheet width direction that form part of the opening end surface 14 are referred to as inclined portions 140. As shown in Fig. 4, this inclined portion 140 is cut out on the exhaust path 12 side, and the length of this cutout increases linearly from the top to the bottom. Therefore, when viewed from the exhaust path 12 side, it can be said that the inclined portion 140 recedes from top to bottom. In other words, when viewing the exhaust member 4 from the center side in the sheet width direction to the end side, the inclined portion 140 recedes from the downstream side (exhaust port 11 side) to the upstream side (mouthpiece 1 side) in the flow direction of the airflow flowing from the decompression chamber 3 side toward the inside of the exhaust member 4. If the sides 12b, 12c were provided straight from the top to the bottom end, the inflow of air from both ends would be obstructed by the sides 12b, 12c near the bottom end. Therefore, this inclined portion 140 is designed to ensure the air flow rate at both ends and suck in air across the width of the sheet so as not to interfere with the flow of air (atmosphere).

[0046] 8, the inlet region 5 is formed so that the end portion close to the inclined portion 140 is wider than the central portion. That is, the lower surface 12e is configured so that the distance between the lower surface 12e and the cover 9 is greater in the areas close to the side surfaces 12b and 12c than in the central portion. If the area of ​​the lower surface 12e near the inclined portion 140 facing the cover 9 is called the widened portion 16, the widened portion 16 is formed in a flat shape over a length of 3 to 10% of the length of the exhaust member 4 (the length in the seat width direction) from the position contacting the inclined portion 140 toward the center. The portion of the undersurface 12e facing the cover 9 between the widened portions 16, 16 at both ends is called the flat portion 16a. The portion connecting the widened portion 16 and the flat portion 16a is connected by a plane connecting the ends of the widened portion 16 and the flat portion 16a, as shown in FIG. 8, so that the widened portion 16 and the flat portion 16a are not connected at a right angle, i.e., so that an obtuse angle is formed rather than an acute angle. This portion connecting the widened portion 16 and the flat portion 16a is called the tapered portion 16b. As shown in FIG. 9, if the projected area of ​​the widened portion 16 and the tapered portion 16b in the inflow region 5 is S4 and the projected area of ​​the flat portion 16a is S3, the ratio S4 / (S3+S4) is, for example, 15. The ratio S4 / (S3+S4) is preferably 10 or greater and 20 or less.

[0047] The flat portion 16a is provided with protrusions 15 that protrude cylindrically toward the cover 9 and come into contact with the cover 9, and these protrusions 15 are provided at multiple locations across the seat width direction. Therefore, circular flat portions of the cylindrical outer surface of the protrusions 15 come into contact with the lower surface 12e and the cover 9, respectively, and the circumferential surface of the outer surface is exposed inside the inflow region 5. The protrusions 15 are intended to prevent the cover 9 from bending against stress generated by reduced pressure when the inside of the exhaust member 4 is reduced pressure.

[0048] The shape of the protrusion 15 may be formed into a triangular prism instead of the cylindrical outer surface as described above.

[0049] [Operation of film manufacturing apparatus 100] Examples of various operations of the film manufacturing apparatus 100 will be described below.

[0050] (Film manufacturing) First, in the film manufacturing apparatus 100, a resin mixture supplied from a device such as a resin molding machine or an extruder is discharged in sheet form from the discharge port 6 as the sheet material 7. A negative pressure region is generated on the back side of the sheet material 7 by the decompression chamber 3, so the atmosphere between the sheet material 7 and the casting device 2 is sucked. This reduces the pressure of the air near the contact area, reducing the amount of air trapped between the sheet material 7 and the casting surface of the casting device 2, and the sheet material 7 comes into close contact with the casting device 2. The sheet material 7 rotates along with the rotation of the casting device 2, which is driven to rotate in the direction of the arrow in FIG. 1 (leftward, counterclockwise), and is transported toward the left.

[0051] At this time, the exhaust member 4 sucks air from the decompression chamber 3 through the second suction pipe to prevent droplets d from accumulating in the decompression chamber 3, and the air near the contact area between the sheet material 7 and the casting device 2 is also sucked through the inlet region 5. This further reduces the pressure of the air near the contact area, reducing the amount of air trapped between the sheet material 7 and the casting surface of the casting device 2. In this way, the exhaust member 4 generates a negative pressure region on the back side of the sheet material 7. In other words, the sheet material 7 can be brought into close contact with the casting device 2 using only the exhaust member 4.

[0052] Thereafter, at the destination of the sheet material 7 transported by the casting device 2, a device (not shown) performs processes such as stretching the sheet material 7 and removing the predetermined components, thereby completing the film. In the production of the film, for example, after the process of stretching the sheet material 7, a process of coating the stretched sheet material 7 may be performed, and any other necessary processes are performed as appropriate.

[0053] In the film production apparatus 100 of this embodiment, the exhaust member 4 is spaced apart from the surface of the casting device 2. During film production, air attempts to flow into the decompression chamber 3 from the outside upstream of the exhaust member 4 in the sheet conveyance direction through this gap. However, the exhaust member 4 sucks this air (the so-called accompanying airflow) into the exhaust path 12, preventing it from flowing into the decompression chamber 3. Furthermore, the inflow region 5 is formed to be wider at both ends than at the center in the sheet width direction, so that the accompanying airflow is sufficiently sucked in even at both ends, preventing it from flowing into the decompression chamber 3. Therefore, the flow of droplets d that would otherwise flow backward from the exhaust member 4 toward the decompression chamber 3 due to the accompanying airflow is also suppressed.

[0054] (Discharge of droplets d from the decompression chamber 3) Hereinafter, one embodiment of discharging the droplets d in the decompression chamber 3 into a dust collector or the like will be described. During film production, the predetermined component in the sheet material 7 gasifies when the sheet material 7 is discharged from the discharge port 6. That is, the resin mixture that will become the sheet material 7 is heated until it is discharged from the discharge port 6, but the casting device 2 is cooled. Therefore, the atmosphere in the decompression chamber 3 is low enough to gel the sheet material 7, and the predetermined component that has gasified liquefies when it drops below its liquefaction temperature. Therefore, when this component adheres to the inside of the decompression chamber 3, it becomes droplets d. If these droplets d accumulate and scatter within the decompression chamber 3, they can cause defects or tears in the film.

[0055] As described above, the film manufacturing apparatus 100 is configured so that the air inside the decompression chamber 3 is sucked in through the second suction pipe during film production, and as a result, the droplets d adhering inside the decompression chamber 3 flow from the inlet region 5 into the exhaust path 12 of the exhaust member 4 together with the air inside the decompression chamber 3. This allows the film manufacturing apparatus 100 to suppress the accumulation of droplets d inside the decompression chamber 3.

[0056] As described above, the connecting surfaces 13a to 13h have a curved shape that is convex outward when viewed from the exhaust path 12 side, and therefore, in the exhaust path 12, as shown in Fig. 7, an air current swirling around the sheet width direction as an axis is generated so as to head toward the exhaust port 11. Therefore, since there are no acute angles in the exhaust path 12 where the droplets d can accumulate, the droplets d that have adhered to the inner surface of the exhaust path 12 (the rear surface 12a, the side surfaces 12b to 12c, the top surface 12d, the bottom surface 12e, and the connecting surfaces 13a to 13h) are carried to the exhaust port 11 and discharged while riding on the air current that flows toward the exhaust port 11 while swirling around the sheet width direction as an axis.

[0057] The droplets d adhering to the protrusions 15 flow along the outer peripheral shape of the protrusions 15, flow into the exhaust path 12, and are similarly discharged, since the circumferential surface of the outer surface of the protrusions 15 is exposed to the inflow area 5. In this way, the film manufacturing apparatus 100 can also suppress the accumulation of droplets d inside the exhaust path 12 of the exhaust member 4.

[0058] As described above, the lower portions of the side surfaces 12b, 12c at both ends in the sheet width direction are cut out to provide the inclined portions 140. Therefore, the atmosphere is sucked into the exhaust path 12 from one end to the other end in the sheet width direction. Furthermore, by providing the inclined portions 140 and leaving the lower ends of the side surfaces 12b, 12c as much as possible, the inflow of atmosphere from outside the decompression chamber 3 and the exhaust member 4 is suppressed. The inflow region 5 is formed so that it is wider at the ends than at the center in the sheet width direction. Therefore, the suction flow rate, which tends to be insufficient at both ends in the sheet width direction, is sufficiently ensured, and a uniform volume of atmosphere flows into the exhaust path 12 across the sheet width direction. In this case, if the area of ​​the inflow region 5 is changed only partially (at both ends) in this manner, the pressure difference between it and the central portion becomes significant, and the flow rate of the atmosphere flowing into the exhaust path 12 may pulsate, or the pulsation may be transmitted to the exhaust member 4, causing the exhaust member 4 to vibrate. However, since a tapered portion 16b is provided between both ends and the central portion between them, the pressure difference that occurs between the both ends and the central portion is alleviated by this tapered portion 16b, and the pulsation and vibration are suppressed.

[0059] [effect] According to this embodiment, by providing outwardly convex connecting surfaces 13a to 13h, the accumulation of droplets d within the suction device 101 can be suppressed, while the above-mentioned straightening function allows the droplets d that have flowed from the inlet region 5 into the exhaust path 12 to be discharged to the outside.

[0060] Furthermore, according to this embodiment, the radius of curvature of the connecting surfaces 13a to 13h is 2 mm or more, so that there is no need to provide corners where the atmosphere may stagnate, and therefore the droplets d that have flowed into the exhaust path 12 can be more smoothly discharged to an external device (dust collector).

[0061] Furthermore, according to this embodiment, the ratio S1 / S2 of the opening area S1 of the exhaust port 11 to the area S2 of each of the side surfaces 12b, 12c of the exhaust path 12 is 1 or less, so that a sufficient flow path for discharging the atmosphere can be secured relative to the internal volume of the exhaust path 12, and therefore the droplets d that have flowed into the exhaust path 12 can be smoothly discharged by the dust collector.

[0062] Furthermore, according to this embodiment, the nozzle 12 is positioned such that the linear distance X from the rear surface 12a is 0 mm or more and 10 mm or less, and the linear distance Y from the bottom surface 12e is 0 mm or more and 10 mm or less, so that the flow of droplets d along the inner surface of the exhaust path 12 toward the exhaust port 11 is less likely to be obstructed, and therefore the droplets d that have flowed into the exhaust path 12 can be smoothly discharged by the dust collector.

[0063] Furthermore, according to this embodiment, the connecting surface 13b is formed in a roughly inverted V-shape when viewed from the front, with the center of the sheet width direction as the apex and sloping downward in the vertical direction toward the exhaust port 11, which makes it easier for droplets d running down the lower surface 12e of the exhaust path 12 to flow to the exhaust port 11, and therefore the droplets d that have flowed into the exhaust path 12 can be smoothly discharged by the dust collecting device.

[0064] As described above, according to the present invention, it is possible to provide a film manufacturing apparatus and a suction device that can stably produce high-quality films, sheets, etc. by discharging droplets in the suction device to an external device without allowing them to accumulate in the suction device.

[0065] [Other examples] Additionally, an antioxidant may be mixed into the resin constituting the film during the resin mixing stage before reaching the die 1. In this case, the antioxidant in the sheet material 7 may gasify when the sheet material 7 is discharged from the discharge port 6, and the gas containing this component may solidify if it adheres to the inside of the decompression chamber 3. Even in this case, if the solid antioxidant accumulates and scatters inside the decompression chamber, it can cause defects or tears in the film. For this reason, by using the suction device 101, the antioxidant in the decompression chamber 3 can be forced to flow from the inlet region 5 into the exhaust path 12 and discharged to the dust collector.

[0066] The suction device 101 can also be used in a process of applying a coating or the like to the substrate film from which the predetermined components have been removed by stretching. For example, a process of coating a film with a coating material containing inorganic particles, a resin binder component for bonding the inorganic particles to each other and to the film, and a solvent for diluting the binder component to reduce the viscosity of the coating material to a level that can withstand the coating process can be mentioned. In such a process, the coating material is ejected onto the surface of the film, for example, from a slit die, and then the solvent is evaporated in a drying process to form a coating film. The binder component is the film-constituting resin of the present invention, and the solvent is the predetermined component of the present invention.

[0067] As mentioned above, if a volatile compound is used as the solvent, the solvent will evaporate from the coating material supplied from the die. If such a solvent remains in the atmosphere, it may wet the binder component of the coating film after drying (after the solvent evaporates). Therefore, by using the suction device 101, the droplets d in the decompression chamber 3 can flow from the inlet region 5 into the exhaust path 12 and be discharged to the dust collector.

[0068] If there is a risk that the predetermined component may be gasified and liquefied in other steps, it is preferable to use the suction device 101 as appropriate.

[0069] [Variations] In the above embodiment, the connecting surfaces 13a to 13h are formed in a curved shape, but as long as the retention of droplets d in the exhaust path 12 can be suppressed, the connecting surfaces 13a to 13h may be flat, as shown in FIG. 10. In this case, the connecting surfaces 13a to 13h are, for example, as described below. The connecting surface 13a connects the rear surface 12a and the top surface 12d at an angle (diagonal) relative to these surfaces so that a connecting portion between these surfaces forms an obtuse angle when viewed from the exhaust path 12. The connecting surface 13b connects the rear surface 12a and the bottom surface 12e at an angle (diagonal) relative to these surfaces so that a connecting portion between these surfaces forms an obtuse angle when viewed from the exhaust path 12. The connecting surface 13c connects the side surface 12b and the top surface 12d at an angle (diagonal) relative to these surfaces so that a connecting portion between these surfaces forms an obtuse angle when viewed from the exhaust path 12. Connecting surface 13d connects side surface 12c and top surface 12d at an angle (diagonal) relative to them so that the connection between them forms an obtuse angle when viewed from exhaust path 12. Connecting surface 13e connects side surface 12b and bottom surface 12e at an angle (diagonal) relative to them so that the connection between them forms an obtuse angle when viewed from exhaust path 12. Connecting surface 13f connects side surface 12c and bottom surface 12e at an angle (diagonal) relative to them so that the connection between them forms an obtuse angle when viewed from exhaust path 12. Connecting surface 13g connects rear surface 12a and side surface 12b at an angle (diagonal) relative to them so that the connection between them forms an obtuse angle when viewed from exhaust path 12. Connecting surface 13h connects rear surface 12a and side surface 12c at an angle (diagonal) relative to them so that the connection between them forms an obtuse angle when viewed from exhaust path 12. Therefore, even in this case, when viewed from the exhaust passage 12, no acute angle of 90° or less is formed, and each of the connecting surfaces 13a to 13h is formed at an obtuse angle. Moreover, instead of forming each of the connecting surfaces 13a to 13h flat as shown in this modified example, each of the connecting surfaces 13a to 13h may be provided with one or more corners that bend at an obtuse angle when viewed from the exhaust path 12. Examples of cases where the above-mentioned predetermined components may gasify and then liquefy or solidify will be specifically described below. FIG. 11 shows an example of an apparatus for producing fibers using polyethylene terephthalate as a molding resin for a target resin member and polystyrene as a predetermined component that gasifies at a lower temperature than the molding resin, as described in International Publication WO 2017 / 164162, for example. In FIG. 11, the same components as those in FIG. 1 are designated by the same reference numerals and will not be described again. In this apparatus, an exhaust port 11 is formed on the rear surface 12a of the exhaust member 4. In FIG. 11, the reference numeral 200 schematically indicates a yarn discharged from a spinneret 1. When yarn is produced using such an apparatus, when the mixture of polyethylene terephthalate and polystyrene is cooled, the polystyrene component liquefies or solidifies and tends to adhere to the inner surface of exhaust member 4. However, since the inner surface of exhaust member 4 is formed to have an obtuse angle, the adhesion of the polystyrene component is suppressed and the polystyrene component is exhausted to exhaust port 11. [Explanation of symbols]

[0070] 1 nozzle 2 Casting equipment 3. Decompression Chamber 3a back side 4 Exhaust parts 5 Inflow area 6 Outlet 7 Sheet material 8 Openings 11 Exhaust port 12 Exhaust duct 12a back side 12b,12c side 12d top 12e Bottom 13a~13h Connecting surface 14 Opening end face 140 Inclined section 15 protrusion 15a Projecting end surface 16 Widening section 16a Flat area 16b Tapered section 100 Film manufacturing equipment 101 Suction device d droplet

Claims

1. A film manufacturing apparatus for manufacturing a film using a resin mixture obtained by mixing a film-constituting resin and a predetermined component that gasifies at a lower temperature than the film-constituting resin, an exhaust member having exhaust ports for discharging the predetermined components provided at both ends in a width direction (TD); an inflow region extending in the width direction (TD) and allowing the predetermined component to flow into the exhaust member; the exhaust member has a surface facing the inflow region that is open in the width direction and has an exhaust path that communicates with the exhaust port, The exhaust path is A flat back surface, A flat top surface located on the upper side, a planar lower surface located on the lower side; a first connecting surface that connects the rear surface and the top surface so that a connecting portion between the rear surface and the top surface forms an obtuse angle when viewed from the exhaust path; a second connecting surface that connects the rear surface and the lower surface so that a connection portion between the rear surface and the lower surface forms an obtuse angle when viewed from the exhaust path, Film manufacturing equipment.

2. The film manufacturing apparatus according to claim 1, The exhaust path is a planar first side surface located at one end side in the width direction (TD); a planar second side surface located on the other end side in the width direction (TD); a third connecting surface that connects the first side surface and the top surface so that a connecting portion between the first side surface and the top surface forms an obtuse angle when viewed from the exhaust path; a fourth connecting surface that connects the second side surface and the top surface so that a connection portion between the second side surface and the top surface forms an obtuse angle when viewed from the exhaust path; a fifth connecting surface that connects the first side surface and the lower surface such that a connection portion between the first side surface and the lower surface forms an obtuse angle when viewed from the exhaust path; a sixth connecting surface that connects the second side surface and the lower surface such that a connecting portion between the second side surface and the lower surface forms an obtuse angle when viewed from the exhaust path; a seventh connecting surface that connects the rear surface and the first side surface so that a connecting portion between the rear surface and the first side surface forms an obtuse angle when viewed from the exhaust path; an eighth connecting surface that connects the rear surface and the second side surface so that a connecting portion between the rear surface and the first side surface forms an obtuse angle when viewed from the exhaust path; Film manufacturing equipment.

3. The film manufacturing apparatus according to claim 2, the first connecting surface, the second connecting surface, the third connecting surface, the fourth connecting surface, the fifth connecting surface, the sixth connecting surface, the seventh connecting surface, and the eighth connecting surface are each formed into a curved surface that is convex toward an outside of the exhaust member. Film manufacturing equipment.

4. The film manufacturing apparatus according to claim 3, The radius of curvature of the first connecting surface and the second connecting surface is 2 mm or more. Film manufacturing equipment.

5. The film manufacturing apparatus according to claim 1, The lower side of the open end surface of the exhaust member is cut out to form the inflow area. Film manufacturing equipment.

6. The film manufacturing apparatus according to claim 1, the exhaust path has a pair of flat side surfaces on which the exhaust port is provided, a ratio S1 / S2 of an opening area S1 of the exhaust port to an area S2 of the side surface is 1 or less; Film manufacturing equipment.

7. The film manufacturing apparatus according to claim 1, the exhaust path has a pair of flat side surfaces on which the exhaust port is provided, The exhaust port is provided at a position where the linear distance from the rear surface is 0 mm or more and 10 mm or less and the linear distance from the bottom surface is 0 mm or more and 10 mm or less. Film manufacturing equipment.

8. The film manufacturing apparatus according to claim 1, The second connecting surface is inclined downward from a vertex at the center in the width direction (TD) toward the exhaust port. Film manufacturing equipment.

9. a die provided with a discharge port for discharging the resin mixture; a casting device that cools and solidifies the resin mixture discharged from the die while transporting it; a decompression chamber that covers a decompression space between the resin mixture discharged from the die and the casting device, and is provided upstream of the discharge port in the conveying direction (MD) of the resin mixture, and that sucks out air inside to bring the resin mixture into close contact with the casting device, The film manufacturing apparatus according to claim 1 is configured to suck, via the inflow area, at least one of droplets and solids generated due to the predetermined component and adhering to the inside of the decompression chamber on the upstream side in the conveying direction of the decompression chamber. Film manufacturing equipment.

10. A suction device attached to a resin molding machine that molds a target resin member using a resin mixture formed by heating a molding resin of the target resin member and a predetermined component that gasifies at a lower temperature than the molding resin, an exhaust member provided with an exhaust port for exhausting the predetermined component; an inflow region for allowing the predetermined component to flow into the exhaust member, the exhaust member is recessed so that a surface facing the inflow area is open, and has an exhaust space communicating with the exhaust port, The exhaust space is A flat back surface, A flat top surface located on the upper side, a planar lower surface located on the lower side; a first connecting surface that connects the rear surface and the top surface so that a connecting portion between the rear surface and the top surface forms an obtuse angle when viewed from the exhaust space; a second connecting surface that connects the rear surface and the lower surface such that a connecting portion between the rear surface and the lower surface forms an obtuse angle when viewed from the exhaust space, Suction device.

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