JP2017036146A - Web guidance device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a wrinkle, sag, streak scratch, and meandering of a web.SOLUTION: A web guide roller 21 comprises an airflow roller 28 and a pair of edge rollers 29 provided at both end parts of the airflow roller 28 in an axial direction. The airflow roller 28 is formed of a porous member, forms an air layer between an outer peripheral surface and a web 12 by making air discharged from a through hole 27 of an inner cylinder 22 flow out from the outer peripheral surface so as to ooze, and supports a central part of the web 12 in a width direction in a non-contact state through the air layer. The edge rollers 29 support both side parts of the web 12 in a contact state. The airflow roller 28 and the edge rollers 29 have the same external diameter, and boundaries of these rollers are formed flush with each other.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a web guidance device that guides web travel.

  Manufacturing equipment such as a functional film such as a magnetic tape, a photographic film, or an optical function film includes a transport device for transporting these long films (hereinafter sometimes referred to as webs). As a conveying device, for example, as described in Patent Document 1 below, a device that floats and conveys the entire web is known. Moreover, as a conveying apparatus, as described in the following patent document 2, for example, a stepped roller whose both end portions are larger in diameter than the center portion (width direction center portion) is used, and the center portion of the web is floated. In some cases, both side portions are conveyed in contact with rollers.

JP, 2014-10162, A JP 2001-106402 A

  However, in the apparatus described in Patent Document 1, since the entire web is levitated, there is a problem that the web being conveyed “meanders”. On the other hand, in the apparatus described in Patent Document 2, since the end portion is in contact with the roller, the above-described “meandering” problem can be prevented, but since the stepped roller is used, the web is caused by the step of the roller. In addition, problems such as “wrinkles”, “sagging”, and “streaky wounds” occur.

  The present invention has been made in view of the above background, and can prevent problems such as “wrinkles”, “sagging”, and “streak-like scratches” while preventing problems of “meandering” of the web. The purpose is to provide.

  In order to achieve the above object, the present invention provides a web guide device for guiding the conveyance of a web in the longitudinal direction, with a peripheral surface contacting both sides of one side of the web, and a pair of rotating along with the conveyance of the web Provided between the contact support part and one and the other of the pair of contact support parts, air is allowed to flow out from the outer peripheral surface to form an air layer between the outer peripheral surface and the web, and non-contact through the air layer And a non-contact support portion having an outer peripheral surface flush with the peripheral surface of the contact support portion.

  The non-contact support part may be formed from a porous member having air permeability.

  The porous member may be at least one of a ceramic sintered body, a porous metal, and a porous plastic.

  The contact support portion may be rotated by a frictional force with the web.

  A rotation force supply unit that supplies a rotation force to the contact support unit may be provided, and the contact support unit may be rotated by the rotation force supplied from the rotation force supply unit.

  The contact support portion preferably rotates within a range in which the speed difference between the moving speed of the peripheral surface of the contact support portion and the web conveyance speed is 5% or less of the web conveyance speed.

  The web thickness is preferably in the range of 40 μm or less.

  An air layer may be configured by accompanying air flowing along with the web being conveyed and outflowing air flowing out from the outer peripheral surface of the non-contact support portion.

  An air amount control unit is provided that controls the amount of at least one of the outflow air and the accompanying air so that the volume of the outflowing air constituting the air layer is 5% or less of the volume of the accompanying air constituting the air layer. Also good.

  You may provide the conveyance control part which controls the conveyance speed of a web within the range of 1 m / min or more and 200 m / min or less, More preferably, 10 m / min or more and 100 m / min or less.

  The web may be separated from the non-contact support portion at a predetermined separation position, and the non-contact support portion may cause the outflow air flowing out from the outer peripheral surface to flow out toward the separation position web.

  You may provide the air layer thickness control part which controls the thickness of an air layer in the range larger than 0 micrometer and less than 15 micrometers.

  It is preferable that the total contact width of both sides of the web in contact with the contact support portion is in the range of 1% or more and less than 5% of the width of the web.

  In the present invention, web conveyance is guided by a web guide roller that supports both sides of the web in contact with each other and supports the web central portion (width direction central portion) in a non-contact state via an air layer. Therefore, the problem of “meandering” that occurs when the entire web is lifted can be prevented. Further, in the present invention, the outer peripheral surface of the contact support portion that supports the web in contact with the outer peripheral surface of the non-contact support portion that supports the web in a non-contact state is flush with the stepped roller. It can also prevent “wrinkles”, “sagging”, “striated wounds” and the like that occur when there is a crack.

It is explanatory drawing which shows the outline of a web conveyance apparatus. It is a perspective view which shows the structure of a web guidance apparatus. It is an exploded view of a web guide roller. It is sectional drawing which shows a cross section perpendicular | vertical to the axis | shaft of a web guide roller. It is sectional drawing which shows the cross section of the axial direction of a web guide roller. It is sectional drawing which shows a cross section perpendicular | vertical to the axis | shaft of a web guide roller. It is a perspective view which shows the structure of a web guidance apparatus. It is explanatory drawing which shows the outline of solution film-forming equipment.

  In FIG. 1, a web conveying device 10 includes a feeding unit 13 that continuously feeds a web 12 from a raw roll 11 wound in a coil shape, and a functional material applied to the surface of the web 12 to form a magnetic coating film or A coating unit 14 for forming a functional coating film such as a photosensitive coating film or an optical functional coating film, a drying unit 15 for drying the coating film, and a web 12 (hereinafter referred to as a wet film 16a, a drying film) on which the coating film is formed. 16b), and a take-up portion 17 that takes up the coil again.

  The web 12 is a flexible support, and has a width of 100 mm to 3000 mm and a length of 100 m to 9000 m, for example. As a material of the web 12, polyethylene terephthalate (hereinafter sometimes referred to as PET), polyethylene-2,6-naphthalate, cellulose diacetate, cellulose triacetate, cellulose acetate propionate, polyvinyl chloride, polyvinylidene chloride, polycarbonate, Plastic films such as polyimide and polyamide; paper; paper coated or laminated with α-polyolefins having 2 to 10 carbon atoms such as polyethylene, polypropylene, and ethylene butene polymers; metal foils such as aluminum, copper, and tin; is there.

  The winding unit 17 is provided with a motor 18 and a motor control unit (conveyance control unit) 19. The motor 18 is connected to a winding shaft 17a on which the web 12 is wound, and is driven and controlled by the motor control unit 19 to rotate the winding shaft 17a. Then, the web 12 is conveyed from the feeding unit 13 toward the winding unit 17 by the rotation of the winding shaft 17a. Thus, the motor control unit 19 functions as a conveyance control unit of the present invention that controls the conveyance of the web 12.

  In addition, although the conveyance speed of the web 12 can be set freely, it is preferable to set it as 1 m / min or more and 200 m / min or less. As will be described later, when the web 12 is transported at a high speed, the web 12 being transported may flutter. On the contrary, if the conveyance speed of the web 12 is slow, the web 12 being conveyed may be damaged. For this reason, it is more preferable that the conveyance speed of the web 12 is 10 m / min or more and 100 m / min or less.

  Further, a motor for rotating the winding shaft 13 a around which the original fabric roll 11 is wound may be provided, and this motor may be driven and controlled by the motor control unit 19 in the same manner as the motor 18. Further, since the web conveyance device 10 is provided with a plurality of rollers for guiding the conveyance of the web 12 such as a web guide roller 21 described later, a motor for rotating these rollers is provided and driven by the motor control unit 19. You may control.

  A web guiding device 20 is provided between the coating unit 14 and the drying unit 15. The web guide device 20 includes a web guide roller 21, and the web 12 is guided by the web guide roller 21 and conveyed from the coating unit 14 to the drying unit 15. Between the coating unit 14 and the drying unit 15, the web 12 is wound around the web guide roller 21, the lower surface is supported by the web guide roller 21, and is dried by a mountain-shaped conveyance path having the web guide roller 21 as a vertex. It is conveyed to the section 15.

  As shown in FIGS. 2 to 5, the web guide roller 21 includes an inner cylinder 22 fixed to a support portion (not shown), and an outer cylinder 24 rotatably attached to the outside of the inner cylinder 22 via a bearing 23. It is composed of a double pipe structure.

  Pipes (not shown) from the blower 25 are connected to both ends of the inner cylinder 22. The blower 25 is driven and controlled by a blower control unit (air amount control unit) 26 and supplies air into the inner cylinder 22 through a pipe. A plurality of through holes 27 penetrating the side wall are formed in the inner cylinder 22, and the air supplied from the blower 25 is discharged from the through holes 27. In the present embodiment, the web 12 is wound around an angle range of 90 ° above the web guide roller 21 (see FIG. 4). And in this embodiment, the through-hole 27 is provided in the 90 degree angle range above the inner cylinder 22 so that air may be discharged toward this range.

  The outer cylinder 24 includes an airflow roller (non-contact support portion) 28 and a pair of edge rollers (contact support portions) 29 provided at both ends in the axial direction (width direction of the web 12) of the airflow roller 28. Yes.

  The air flow roller 28 is composed of a member having air permeability. Examples of the air-permeable member include a porous member having an open cell structure, and more specifically, a ceramic sintered body, a porous metal, a porous plastic, and the like. The air flow roller 28 causes the air discharged from the through hole 27 of the inner cylinder 22 to flow out from the outer peripheral surface, thereby forming an air layer between the outer peripheral surface and the web 12. The center part (width direction center part) of the web 12 is supported in a non-contact state through the layers. Thus, the airflow roller 28 is a non-contact support part of the present invention.

  The airflow roller 28 may be composed of only one kind of member having air permeability described above, or may be composed of a plurality of kinds of members having air permeability. Moreover, you may use what gave air permeability by providing a some through-hole in the side wall of a cylindrical member like the through-hole 27 of the inner cylinder 27 as an airflow roller.

  However, as will be described later, in the present invention, since the thickness of the air layer formed between the outer periphery of the airflow roller and the web can be reduced to the utmost limit, the air flowing out from the outer peripheral surface of the airflow roller 28 (hereinafter referred to as outflow air and However, if the air can pass without resistance from the inside of the air flow roller 28 to the outer peripheral surface, the supply amount of the outflow air increases more than necessary.

  For this reason, it is preferable that the flow path of the outflow air is narrow and complicated (not linear) so that the outflow air is directed from the inside of the airflow roller 28 toward the outer peripheral surface. Specifically, when the through hole is provided in the air flow roller, the diameter of the through hole is preferably 100 μm or less. Further, when the airflow roller is configured using a porous member, the average pore diameter is preferably 60 μm or less (# 200), and more preferably 30 μm or less (# 400). Porous members include ceramics such as alumina, metals such as stainless steel, plastics, etc., and may be selected depending on the hole diameter, material size, and price.

  On the other hand, unlike the airflow roller 28, the edge roller 29 is a contact support portion of the present invention that supports both sides of the web 12 in contact with each other. As for the edge roller 29, the roller surface which contacts the web 12 is formed from, for example, stainless steel, ceramic, super hard alloy, hard chrome plating, anodized aluminum, or the like. The outer cylinder 24 rotates as the web 12 is conveyed by the frictional force between the edge roller 29 and the web 12.

  Unlike the airflow roller 28, the edge roller 29 does not need to have air permeability. However, if the frictional force between the edge roller 29 and the web 12 is small, the web 12 slips on the surface of the edge roller 29. As a result, the web 12 may “meander”. For this reason, at least the surface of the edge roller 29 may be formed of a porous member, and the frictional force between the web 12 and the edge roller 29 may be increased by unevenness caused by the holes of the porous member. Of course, the frictional force between the web 12 and the edge roller 29 may be increased by subjecting the surface of the edge roller 29 to concavo-convex processing and groove processing such as satin and dimples by blasting.

  The air flow roller 28 and the edge roller 29 have the same outer diameter, that is, the outer cylinder 24 is formed so that the boundary between the air flow roller 28 and the edge roller 29 is flush (see FIG. 5). By doing so, it is possible to prevent problems such as “wrinkles”, “sagging”, and “streak-like scratches” at the boundary between the airflow roller 28 and the edge roller 29 and the web 12 in the vicinity thereof. In the present invention, since both sides of the web 12 are supported in contact with each other, “meandering” of the web 12 can be prevented.

  In the web conveyance device 10 provided with such a web guide roller 21, first, the web 12 is unwound from the raw roll 11 from the unwinding unit 13 and is conveyed to the coating unit 14. In the coating unit 14, a functional material is applied to the surface of the transported web 12, and the wet film 16 a is transported toward the web guide roller 18.

  The wet film 16 a is conveyed to the drying unit 15 by the web guide roller 18. The wet film 16a conveyed to the drying unit 15 is dried by the drying unit 15 to become a dry film 16b, and is wound again in a coil shape by the winding unit 17. The coil-shaped, that is, roll-shaped dry film 16b is transferred to the next processing step and processed into a product.

  In the above embodiment, the web guide roller 21 is described as an example of a free rotation roller that rotates following the conveyance of the web 12 due to the frictional force with the web 12, but from the rotational force supply unit such as a motor. The web guide roller 21 may be rotated by supplying a rotational force to the web guide roller 21. In this case, the web guide roller 21 is rotated so that the difference between the moving speed of the outer peripheral surface of the web guide roller 21 and the conveyance speed of the web 12 is within a range of 1% or less, that is, the rotational force supply unit is driven and controlled. It is preferable to provide a control unit.

  Of course, even when the web guide roller 21 is a free-rotating roller as in the above-described embodiment, the web difference is within a range of 1% or less between the movement speed of the outer peripheral surface of the web guide roller 21 and the web conveyance speed. It is preferable that the guide roller 21 rotates. In this case, the frictional force with the web 12, specifically, the web guide roller 21 (edge roller 29) so that the speed difference between the moving speed of the outer peripheral surface of the web guide roller 21 and the web conveyance speed is 1% or less. ) Surface material, the conveyance tension of the web 12 and the like may be determined.

  Further, the widths of the airflow roller 28 and the edge roller 29, that is, the widths of the non-contact support part and the contact support part can be freely set. However, since the area | region which contacts the contact support part among the webs 12 may generate | occur | produce the "abrasion" etc. accompanying conveyance, if this area | region is large, the area | region which can be used as a product will reduce. On the other hand, if this area is small, the effect of preventing “meandering” of the web is weakened. For this reason, it is preferable that the total width of both sides of the web 12 that come into contact with the contact support portion is 0.5% or more and less than 5% of the entire width of the web 12, and more preferably 1% or more. 3% or less.

  Furthermore, the thickness of the air layer formed between the web 12 and the non-contact support portion can be freely set. However, in the present invention, since the non-contact support part and the contact support part are flush with each other, a so-called stepped roller in which the outer diameter of the roller central part is smaller than the outer diameters of both side parts as in the past is used. The central portion of the web 12 is supported in a non-contact manner, and the thickness of the air layer formed between the non-contact support portion and the web 12 is stepped as compared to the case where both sides of the web 12 are supported in a contact state. It need not be equal to the height of the roller steps. For this reason, in the present invention, it is preferable that the thickness of the air layer is as thin as possible, specifically, in the range of greater than 0 μm and less than 15 μm. By reducing the thickness of the air layer in this way, the amount of air supplied to float the web 12 (the volume of air supplied per unit time) can be suppressed. Further, by reducing the thickness of the air layer, “flapping (vibration in a direction perpendicular to the surface of the web)” of the web 12 can be suppressed.

  In addition, the air layer formed between the web 12 and the non-contact support part includes not only the outflow air that has flowed out of the non-contact support part, but also the periphery of the web accompanying the web as the web is conveyed. Flowing air (hereinafter sometimes referred to as accompanying air) is also included (the air layer is composed of outflow air and accompanying air). As described above, according to the present invention, since the thickness of the air layer can be reduced to the utmost limit, almost all of the air layer is composed of entrained air, specifically, the amount of outflow air composing the air layer is entrained. It is also possible to make the range 5% or less of the air amount of air, and the supply amount of outflow air can be suppressed.

  The air amount of the accompanying air also changes depending on the conveyance speed of the web 12, the amount of the accompanying air increases, and the thickness of the air layer increases, and the conveyance speed of the web 12 is slow. And the amount of entrained air is reduced and the thickness of the air layer is reduced. As the air layer becomes thicker, that is, as the conveyance speed of the web 12 increases, “flapping” is more likely to occur in the web 12 being conveyed. On the contrary, as the thickness of the air layer decreases, that is, as the conveyance speed of the web 12 decreases, the web 12 being conveyed may come into contact with the roller and be damaged. For this reason, it is preferable that the conveyance speed of the web 12 shall be 10 m / min or more and 100 m / min or less from a viewpoint of stabilizing the thickness of an air layer.

  Thus, the air layer formed between the web 12 and the non-contact support part includes outflow air and accompanying air, and the amount of air in the outflow air varies depending on the amount of air blown from the blower 25, The amount of accompanying air varies depending on the web conveyance speed (that is, the rotation speed of the motor 18). That is, the air blow control unit 26 that drives and controls the blower 25 also functions as an air amount control unit of the present invention that controls the air amount of the outflow air constituting the air layer. In addition, the motor control unit 19 that drives and controls the motor 18, that is, the conveyance control unit, also functions as an air amount control unit of the present invention that controls the amount of entrained air that forms the air layer.

  Furthermore, since the thickness of the air layer changes depending on the amount of the outflow air and accompanying air, the air blow control unit 26 and the motor control unit 19 also function as the air layer thickness control unit of the present invention that controls the thickness of the air layer. To do. When the thickness of the air layer is controlled, the air layer is controlled by controlling both the air amount of the outflow air (the amount of air supplied by the blower 25) and the air amount of the accompanying air (the rotational speed of the motor 18). The thickness of the air layer may be controlled to a desired thickness, or the thickness of the air layer may be controlled to a desired thickness by making one constant and controlling only the other.

  In addition, when this invention is applied to the web guidance apparatus which guides conveyance of a comparatively thin web whose thickness is 40 micrometers or less, More preferably, it is 16 micrometers or less, a more remarkable effect is acquired. That is, when the entire web is supported in a non-contact manner as in the prior art, the web is more likely to “flutter” as the thickness of the web decreases. In addition, when using a stepped roller to support the central part of the web in a non-contact manner and supporting the both side parts of the web in contact with each other as in the past, the thinner the web is, the smaller the distance between the central part and the two side parts is. Problems such as “wrinkles”, “sagging”, and “streak-like scratches” are likely to occur. On the other hand, the present invention can prevent the conventional problem even when the web is thin.

  In addition, the present invention provides a more remarkable effect when the web is wound around the web guide roller and the web transport tension is relatively high, such as 200 N / m or more, or even 300 N / m or more. . In other words, when a stepped roller is used as in the prior art, the higher the conveyance tension, the “wrinkles”, “sagging”, and “striated scratches” at or near the boundary between the contact support portion and the non-contact support portion. ] Is likely to occur. On the other hand, in the present invention, since the contact support portion and the non-contact support portion are formed flush with each other, the above-described problem can be prevented even when the conveyance tension is high.

  Furthermore, the present invention can provide a more remarkable effect when the web conveyance tension is relatively low, such as 50 N / m or less, or even 20 N / m or less. That is, when the entire web is lifted and transported as in the prior art, the lower the transport tension, the easier the web “meanders”. On the other hand, in the present invention, only the central portion of the web is floated and both sides are supported in contact with each other, so that the above-described problem can be prevented even when the conveyance tension is low.

  In the above embodiment, the example in which the web 12 is wound around the 90 ° angle range on the upper side of the web guide roller 21 has been described. However, the range in which the web 12 is wound is not limited to this, and can be changed as appropriate. Moreover, although the said embodiment demonstrated by the example comprised so that outflow air might flow out from the area | region where the web 12 was wound among the web guide rollers 21, this invention is not limited to this. For example, the above-described through hole 27 (see FIGS. 3 to 5) may be provided over the entire circumference of the inner cylinder 22, and the web guide roller may be configured to allow the outflow air to flow out from the entire circumference.

  On the contrary, it is good also as a structure which flows out outflow air only from a part of area | region where the web 12 was wound. In this case, like the web guide roller 30 shown in FIG. 6, it is preferable that the outflow air flows out toward the web 12 at the separation position P <b> 1 that is separated from the web guide roller 30. In the explanation using Drawings after Drawing 6, the same numerals are given about the same member as an embodiment mentioned above, and explanation is omitted.

  In FIG. 6, the web 12 is wound around an angle range of 90 ° on the upper side of the web guide roller 30 as in the above-described embodiment. That is, in the example of FIG. 6, the separation position P1 where the web 12 is separated from the web guide roller 30 rotates 45 ° counterclockwise (downstream) when the uppermost portion of the web guide roller 30 is 0 °. It becomes the position. In the example of FIG. 6, a through hole 27 is formed in the inner cylinder 22 so that the outflow air flows out from an angle range of 20 ° centered on the separation position P1.

  As described above, in the present invention, the air layer formed between the web 12 and the airflow roller 28 can be made extremely thin. The air layer also includes accompanying air that flows along with the conveyance of the web 12, and in the present invention, almost all of the air layer can be constituted by the accompanying air. On the other hand, in the vicinity of the separation position P <b> 1, the web 12 is separated from the air flow roller 28, whereby the pressure of the air constituting the air layer is lowered, and the web 12 may come into contact with the air flow roller 28. On the other hand, the problem described above, that is, the contact between the web 12 and the air flow roller 28 can be prevented by adopting a configuration in which the outflow air flows out toward the web 12 at the separation position P1 as shown in FIG. In the example of FIG. 6, for example, the supply amount of outflow air can be suppressed as compared with a configuration in which outflow air flows out from the entire region around which the web 12 is wound.

  In the above-described embodiment, the example in which the airflow roller 28 and the edge roller 29 are integrated and rotated together has been described, but the present invention is not limited to this. For example, as shown in FIG. 7, only the edge roller 29 may be configured to rotate. In FIG. 7, the web guiding device 31 is provided with a main body 32 instead of the above-described air flow roller 28 (see FIGS. 2 and 3). The main body portion 32 is a non-contact support portion of the present invention, the upper portion of which is constituted by a porous member, and allows the air supplied to the inside by the blower 25 to flow out from the upper portion. For example, the bottom surface of the main body 32 is fixed to a floor or the like.

  Support shafts 32 a are provided at both ends of the main body 32. An edge roller 29 is attached to the support shaft 32a and is rotatably supported. Even in such a configuration, that is, a configuration in which the non-contact support portion does not rotate, the same effect as in the above embodiment can be obtained. In addition, when the non-contact support part does not rotate, compared with the case where a non-contact support part rotates, the air quantity of the entrained air which comprises an air layer reduces. For this reason, when it is set as the structure which a non-contact support part does not rotate, the supply amount of outflow air is increased, the conveyance speed of the web 12 is made quick, etc., and the contact with the web 12 and a non-contact support part is prevented. It is preferable to do.

  In the above-described embodiment, an example in which the accompanying air is only naturally generated by the conveyance of the web 12 has been described. However, the accompanying air is not only naturally generated in this way, but for example, compulsory from a blower. Also included in the That is, a blower that generates accompanying air may be provided. Thus, by providing a blower that generates accompanying air, a stable amount of accompanying air can be supplied even in a situation where the accompanying air tends to be insufficient. As a situation where the accompanying air is likely to be insufficient, for example, when the conveyance speed of the web 12 is low, specifically, the conveyance speed of the web 12 is 50 m / min or less, and further 20 m / min or less. Moreover, as a situation where the accompanying air is likely to be insufficient, there is a case where the non-contact support portion does not rotate as in the example of FIG.

  As described above, when a blower that forcibly generates accompanying air is provided, a control unit that controls the blower functions as an air amount control unit of the present invention that controls the amount of the accompanying air. In addition, when a blower that forcibly generates accompanying air is provided, the control unit that controls the blower controls the thickness of the air layer formed between the web 12 and the non-contact support unit. Also functions as an air layer thickness control unit.

  In addition, the present invention is not limited to manufacturing equipment for manufacturing a functional film by applying a functional material to the base film (web) as described above. The present invention can also be applied to solution casting equipment and melt casting equipment that directly produce a film.

  The web guided by the web guiding apparatus of the present invention in solution casting is a so-called wet film containing a solvent after being peeled off from a casting support and a dried film after being dried (hereinafter sometimes simply referred to as a film). ). In solution casting equipment, a dope containing a polymer and a solvent is cast on a casting support to form a casting film on the casting support, and the casting film is peeled off as a film from the casting support. take. Since the peeled film contains a solvent, the solvent is evaporated to dry the film. The dried film is wound up by a winding device so as to be in a roll form or sent to the next process. As an apparatus which implements the next process, the web conveyance apparatus 10 shown in FIG. 1 is mentioned, for example. In addition, the web guided by the web guiding apparatus of the present invention in melt film formation is a film obtained by melting a raw material polymer by a melt extruder and extruding it into a thin film shape.

  The wet film in the solution casting contains a solvent and is heated to accelerate drying. Further, the film in the melt film formation is set to a high temperature of substantially the melting point when extruded from the melt extruder. Thus, even when the web guiding apparatus of the present invention is used to guide a web containing a solvent or a high-temperature web, the same effects as those of the above-described embodiment can be obtained.

  Hereinafter, as an example of an aspect in which the web guide device of the present invention is used in the film forming facility, an aspect in which the web guide roller 21 shown in FIG. 8 is used in the solution film forming facility will be described.

[material]
As the dope raw material, a known polymer and solvent capable of producing a film by solution casting can be used. Among the polymers, cellulose acylate and cyclic polyolefin can be preferably used. Since any of these polymers is basically the same in the construction of the production equipment and the flow of the production method, the case where cellulose acylate film is used as a polymer component will be described below as an example.

Among the cellulose acylates, the ratio of esterifying the hydroxyl group of cellulose with carboxylic acid, that is, the substitution degree of acyl group (hereinafter referred to as acyl substitution degree) satisfies all the conditions of the following formulas (I) to (III) What is satisfied is more preferable. In (I) to (III), A and B are both acyl group substitution degrees, the acyl group in A is an acetyl group, and the acyl group in B has 3 to 22 carbon atoms.
2.5 ≦ A + B ≦ 3.0 (I)
0 ≦ A ≦ 3.0 (II)
0 ≦ B ≦ 2.9 (III)

  Glucose units constituting cellulose and having β-1,4 bonds have free hydroxyl groups at the 2nd, 3rd and 6th positions. Cellulose acylate is a polymer in which some or all of these hydroxyl groups are esterified, and hydrogen of the hydroxyl groups is substituted with acyl groups having 2 or more carbon atoms. Since the degree of substitution is 1 when esterification of one hydroxyl group in the glucose unit is 100%, in the case of cellulose acylate, the hydroxyl groups at the 2nd, 3rd and 6th positions are each 100% ester. The degree of substitution is 3.

  Here, the substitution degree of the acyl group at the 2-position of the glucose unit is DS2, the substitution degree of the acyl group at the 3-position is DS3, and the substitution degree of the acyl group at the 6-position is DS6. The total acyl group substitution degree determined by DS2 + DS3 + DS6 is preferably 2.00 to 3.00, more preferably 2.22 to 2.90, and even more preferably 2.40 to 2.88. . Further, DS6 / (DS2 + DS3 + DS6) is preferably 0.28 or more, more preferably 0.30 or more, and further preferably 0.31 to 0.34.

  There may be only one kind of acyl group, or two or more kinds. When there are two or more acyl groups, it is preferable that one of them is an acetyl group. DSA + DSB, where DSA is the sum of the substitution degrees of the hydrogens of the hydroxyl groups at the 2nd, 3rd and 6th positions with the acetyl group, and DSB is the sum of the substitution degrees other than the acetyl groups at the 2nd, 3rd and 6th positions The value of is preferably 2.22 to 2.90, particularly preferably 2.40 to 2.88. DSB is preferably 0.30 or more, and particularly preferably 0.70 or more. Further, 20% or more of the DSB is preferably a substituent at the 6-position hydroxyl group, more preferably at least 25%, even more preferably 30% or more, and particularly preferably 33% or more is a substituent at the 6-position hydroxyl group. Preferably there is. The 6-position DSA + DSB value of cellulose acylate is preferably 0.75 or more, more preferably 0.80 or more, and particularly preferably 0.85 or more. By using the cellulose acylate as described above, a dope having preferable solubility and a dope having low viscosity and good filterability can be produced. In particular, when a non-chlorine organic solvent is used, the above cellulose acylate is preferable.

  The acyl group having 2 or more carbon atoms may be an aliphatic group or an aryl group, and is not particularly limited. For example, there are cellulose alkylcarbonyl ester, alkenylcarbonyl ester, aromatic carbonyl ester, aromatic alkylcarbonyl ester, etc., and these may each further have a substituted group. Propionyl group, butanoyl group, pentanoyl group, hexanoyl group, octanoyl group, decanoyl group, dodecanoyl group, tridecanoyl group, tetradecanoyl group, hexadecanoyl group, octadecanoyl group, iso-butanoyl group, t-butanoyl group, cyclohexane Examples thereof include a carbonyl group, an oleoyl group, a benzoyl group, a naphthylcarbonyl group, and a cinnamoyl group. Among these, a propionyl group, a butanoyl group, a dodecanoyl group, an octadecanoyl group, a t-butanoyl group, an oleoyl group, a benzoyl group, a naphthylcarbonyl group, a cinnamoyl group, and the like are more preferable, and a propionyl group and a butanoyl group are particularly preferable.

  The details of cellulose acylate are described in paragraphs [0140] to [0195] of JP-A-2005-104148, and these descriptions can also be applied to the present invention.

  Solvents for producing the dope include aromatic hydrocarbons (eg, benzene, toluene, etc.), halogenated hydrocarbons (eg, dichloromethane, chloroform, chlorobenzene, etc.), alcohols (eg, methanol, ethanol, n-propanol, Examples thereof include n-butanol, diethylene glycol, etc., ketones (eg, acetone, methyl ethyl ketone, etc.), esters (eg, methyl acetate, ethyl acetate, propyl acetate, etc.) and ethers (eg, tetrahydrofuran, methyl cellosolve, etc.). Here, the dope is a polymer solution or dispersion obtained by dissolving a polymer in a solvent or dispersing in a dispersion medium.

  As the solvent, among the above compounds, a halogenated hydrocarbon having 1 to 7 carbon atoms is preferable, and dichloromethane is most preferable. And from the viewpoint of properties such as solubility of cellulose acylate, peelability from the cast film support, mechanical strength of the film, and optical properties of the film, one or several kinds of alcohols having 1 to 5 carbon atoms are used. Is preferably mixed with dichloromethane. At this time, the content of the alcohol is preferably 2% by weight to 25% by weight and more preferably 5% by weight to 20% by weight with respect to the whole solvent. Preferable specific examples of the alcohol include methanol, ethanol, n-propanol, isopropanol, n-butanol, etc. Among them, methanol, ethanol, n-butanol, or a mixture thereof is preferably used.

  For the purpose of minimizing the influence on the environment, the dope may be manufactured without using dichloromethane. As the solvent in this case, an ether having 4 to 12 carbon atoms, a ketone having 3 to 12 carbon atoms, and an ester having 3 to 12 carbon atoms are preferable, and these may be appropriately mixed and used. These ethers, ketones and esters may have a cyclic structure. A compound having two or more functional groups of ether, ketone and ester (that is, —O—, —CO— and —COO—) can also be used as the solvent. The solvent may have another functional group such as an alcoholic hydroxyl group in the chemical structure.

  Depending on the purpose, the dope may be added with various known additives such as a plasticizer, an ultraviolet absorber (UV agent), a deterioration preventing agent, a slipping agent, and a peeling accelerator. For example, as the plasticizer, phosphate plasticizers such as triphenyl phosphate and biphenyldiphenyl phosphate, phthalate plasticizers such as diethyl phthalate, and various known plasticizers such as polyester polyurethane elastomers are used. be able to.

  The dope whose cellulose acylate density | concentration is 5 to 40 weight% is manufactured using the above raw material. The cellulose acylate concentration is more preferably in the range of 15% by weight to 30% by weight, and further preferably in the range of 17% by weight to 25% by weight. The concentration of the additive is preferably in the range of 1% by weight to 20% by weight with respect to the entire solid content.

  Regarding the production of the dope, the raw material dissolution method, filtration method, defoaming, and addition method are described in detail in paragraphs [0517] to [0616] of JP-A-2005-104148. The contents of can also be applied to the present invention.

[Film production method]
FIG. 8 is a schematic view showing the solution casting apparatus 50. However, the present invention is not limited to the solution casting apparatus 50. The solution casting apparatus 50 includes a casting chamber 53 which is a wet film (web) 52 which is a cellulose acylate film containing a solvent by casting a dope 51 in which cellulose acylate is dissolved in a solvent, and a wet film. A first drying chamber 56 that dries while conveying 52, a tenter 57 that dries while conveying the wet film 52 while holding both side ends of the wet film 52 that has left the first drying chamber 56, A second device which is an edge-cutting device 58 for cutting off both end portions and a cellulose acylate film 59 (which is a web of the present invention and hereinafter simply referred to as a film) which is dried while transporting the wet film 52 and contains almost no solvent. A drying chamber 61, a cooling chamber 62 for cooling the film 59, a static eliminator 63 for reducing the charge amount of the film 59, and embossing at the side end A knurling roller pair 66 to perform the engineering, is provided with a winding portion 67 for winding the film 59.

  The casting chamber 53 includes a casting die 71 that flows out of the dope 51 and a band 72 as a casting support. The casting die 71 is preferably a coat hanger type die.

  A band 72 as a casting support is wound around a backup roller 73 that rotates in the circumferential direction, and continuously travels as the backup roller 73 rotates. The backup roller 73 is provided with driving means (not shown), and is rotated by this driving means.

  The backup roller 73 has a flow path (not shown) through which the heat transfer medium passes. A heat transfer medium circulation device (not shown) is connected to the backup roller 73, and the heat transfer medium circulation device controls the temperature of the heat transfer medium and places the heat transfer medium in the flow path. Circulating supply. Accordingly, the peripheral surface temperature of the backup roller 73 is controlled so that the temperature of the band 72 in contact with the backup roller 73 becomes a predetermined value. The temperature of the band 72 is appropriately set according to the type of solvent, the type of solid component, the concentration of the dope 51, and the like.

  A casting bead is formed from the casting die 71 to the band 72, and a casting film 78 is formed on the band 72. A decompression chamber 76 is provided on the upstream side of the casting bead. Reduce the upstream area of the casting beat to stabilize the casting bead.

  The casting chamber 53 has a temperature control device 77 for keeping the internal temperature at a predetermined value, and a condenser (not shown) for condensing and recovering the solvent evaporated from the dope 51 and the casting film 78. Are provided. A recovery device (not shown) for recovering the condensed and liquefied solvent is provided outside the casting chamber 53. The solvent recovered by the recovery device is regenerated and reused as a solvent for dope production.

  The casting chamber 53 is provided with a peeling roller 85 that supports the wet film 52 in order to peel the casting film 78 from the band 72. The cast film 78 is dried until it is self-supporting, and then peeled off from the band 72. The weight of the residual solvent of the casting film 78 at the time of peeling is preferably 10 to 200 when the weight of the solid content is 100.

  Instead of the band 72 and the backup roller 73, a drum that rotates in the circumferential direction can also be used. In this case, the casting film 78 is cooled to be gelled to have self-supporting properties. By drying while cooling, the timing of stripping can be accelerated.

  The first drying chamber 56 is provided with a blower (not shown). The temperature of the drying air from the blower is preferably in the range of 20 ° C to 250 ° C. The first drying chamber 56 is provided with a web guide roller 18 for guiding the wet film 52 to the tenter 57. Thereby, the “meandering” of the wet film 52 (web) can be suppressed, and the wet film 52 can be stably conveyed. In addition, there is no occurrence of “wrinkles”, “sagging”, and “streak-like scratches” at or near the boundary between the airflow roller 28 (non-contact support portion) and the edge roller 29 (contact support portion). . A plurality of web guide rollers 18 may be provided in the first drying chamber 56. Further, all of the plurality of rollers provided in the conveyance path of the first drying chamber 56 may be the web guide roller 18, or only a part thereof may be the web guide roller 18.

  In the first drying chamber 56, for the plurality of rollers arranged in the conveyance path, the draw film (conveyance tension) is applied to the wet film 52 by making the rotation speed of the downstream roller faster than the rotation speed of the upstream roller. That is, tension in the transport direction can be applied. Thereby, the sagging and deformation of the wet film 52 can be prevented.

  In the first drying chamber 56, the wet film 52 has been described as an example in which the wet film 52 is conveyed by a path that swings up and down by being sequentially wound around rollers that are alternately arranged up and down. It is not limited. For example, the transport path of the wet film 52 in the first drying chamber 56 may be horizontal, and a plurality of rollers may be horizontally disposed on the lower surface side of the wet film 52 so as to support the lower surface of the wet film 52.

  Further, the first drying chamber 56 may be provided with a blower for blowing dry air for evaporating the solvent from the wet film 52 and drying it. In this case, in the wet film 52, the surface facing the band 72 is less likely to evaporate the solvent than the surface on the opposite side, so that the surface of the wet film 52 facing the band 72 is dried. It is preferable to blow wind. Furthermore, in this example, although the example which provides the 1st drying chamber 56 was demonstrated, the 1st drying chamber 56 may be abolished and the tenter 57 mentioned later may be arrange | positioned immediately after the backup roller 73. FIG.

  Both ends of the wet film 52 sent to the tenter 57 are held by holding means (not shown), and are conveyed by movement of the holding means. And it dries during this conveyance. Examples of the holding means include a clip that holds the side portion of the wet film 52, and a plurality of pins that pierce and hold the side portion. When the band 72 is used as a casting support and the casting film 78 is peeled off after a part of the solvent is evaporated, the holding means in the tenter 57 is preferably a clip, while the drum is used as the casting support. When the cast film that has been used and peeled off with little evaporation of the solvent is peeled off, a pin is preferable as the holding means in the tenter 57. In the tenter 57, the wet film 52 is dried at a temperature of 120 ° C. or higher and 180 ° C. or lower.

  After the wet film 52 is dried by the tenter 57, both end portions thereof are cut and removed by the ear clip device 58. The separated both ends are sent to a crusher 89 by a cutter blower (not shown). By the crusher 89, the side end portion is crushed into chips. This chip is reused for dope production.

  On the other hand, the wet film 52 from which both side ends have been removed is sent to the second drying chamber 61 and further dried while being conveyed. Although the internal temperature of the 2nd drying chamber 61 is not specifically limited, It is preferable to set it as 60-140 degreeC. Similarly to the first drying chamber 56, the web guide roller 18 is also provided in the conveyance path of the second drying chamber 61. Thereby, the “meandering” of the wet film 52 (web) can be suppressed, and the wet film 52 can be stably conveyed. In addition, “wrinkles”, “sagging”, and “streak-like scratches” may occur at the boundary between the airflow roller 28 (non-contact support portion) and the edge roller 29 (contact support portion) or in the vicinity thereof. Absent. Note that all of the plurality of rollers provided in the conveyance path of the second drying chamber 61 may be the web guide rollers 18, or only some of them may be the web guide rollers 18.

  The dried film 59 is preferably cooled to approximately room temperature in the cooling chamber 62.

  Inside the winding unit 67, a winding device 92 for winding the film 59 and a press roller 93 for controlling the tension at the time of winding are provided.

  In addition, the conveyance path of the solution casting apparatus 50 includes a roller (not shown), and the web guide roller of the present invention can be used for any of these rollers. This makes it possible to suppress the “meandering” of the web (wet film 52 or film 59) and to stably convey the web. In addition, there is no occurrence of “wrinkles”, “sagging”, and “streak-like scratches” at or near the boundary between the airflow roller 28 (non-contact support portion) and the edge roller 29 (contact support portion). .

[Example]
In order to demonstrate the effect of the web guiding apparatus of the present invention, Examples 1 to 6 using the web guiding apparatus of the present invention were compared with Comparative Examples 1 to 7 using a conventional web guiding apparatus. Hereinafter, the comparison results will be described with reference to Tables 1 and 2.

  As shown in Table 1, in Examples 1 to 6, the web guide roller 21 shown in FIGS. 2 to 5 is used as the web guide device, and the central portion of the web 12 is conveyed in a non-contact state. The both sides of the were conveyed in contact. In the web guide rollers 21 of Examples 1 to 6, the diameter is 80 mm, the width of the airflow roller 28 is 1450 mm, and the material of the airflow roller 28 is a porous metal. And in Examples 1-6, the width | variety of the web 12 supported in a contact state with the edge roller 29 was 20 mm per side. Moreover, in Examples 1-6, the air amount of the outflow air which flows out from the air blower 25, ie, the surrounding surface of the airflow roller 28, so that the floating amount (the thickness of an air layer) of the web 12 by the airflow roller 28 may be 3 micrometers. Controlled. At this time, the supply amount of outflow air necessary for the floating of the web 12 was 1 L / min, and the air pressure was 0.3 MPa. The flying height of the web 12 (the thickness of the air layer) was measured with a Keyence laser displacement meter LK-G10.

  As shown in Table 2, in Comparative Examples 1 to 4, a cylindrical web guide roller having no step on the outer periphery was used as the web guide device, and the entire web 12 was conveyed in contact with the web guide roller. The web guide rollers of Comparative Examples 1 to 4 have a surface length (width) of 1600 mm, a diameter of 100 mm, nickel base, hard chrome plating, and buff finish (surface roughness Ra <0.6 μm).

  In Comparative Examples 5 to 7, a stepped roller was used as the web guiding device, and the central portion of the web 12 was conveyed in a non-contact state, and both sides of the web 12 were conveyed in a contact state. In the web guide rollers of Comparative Examples 4 and 5, the width of the central portion is 1450 mm, the width of both side portions is 50 mm per side, the diameter of the central portion is 250 mm, and the diameter of both side portions is 300 mm. And in the comparative examples 5-7, the width | variety of the web 12 supported in a contact state by the both sides of a web guide roller was 20 mm per side. In Comparative Examples 5 to 7, the amount of air discharged from the peripheral surface of the web guide roller was controlled so that the center of the web guide roller had a flying height of 25 mm at which the web 12 floated. At this time, the supply amount of air necessary for the floating of the web 12 was 10,000 L / min.

  Further, as shown in Tables 1 and 2, in Examples 1 to 6 and Comparative Examples 1 to 7, a PET film having a width of 1490 mm was used as the web 12. Under such conditions, the thickness, conveyance speed, and conveyance tension of the web 12 are changed, and “wrinkles / sag (wrinkles and sagging in the boundary between both sides and the center of the web 12 and its vicinity)”, “ Edge scratches (striated scratches at the boundary between both side portions and the central portion of the web 12) "," Product scratches (scratches at the central portion (product portion) of the web 12) "," Meandering (position in the width direction of the web 12) Evaluation) was performed.

  “Wrinkles / sag”, “edge scratches”, and “product scratches” were evaluated by reflecting light on the web 12 and visually inspecting the reflection state. As for “wrinkles / sag”, if “wrinkles” or “sag” is recognized at the boundary between the both sides and the center of the web 12 and its vicinity, it is evaluated as “fail” and not recognized. The case was evaluated as “pass”. As for “edge flaws”, if “streaky flaws” are recognized at the boundary between both sides and the center of the web 12, it is evaluated as “failed”, and if it is not recognized, “passed”. It was evaluated. Furthermore, regarding “product scratches”, when “scratches” were observed in the product part at the center of the web 12, “failure” was evaluated, and when it was not recognized, “pass” was evaluated. As for “meandering”, the end position of the web 12 was monitored, and when a deviation of 1 mm or more occurred, it was evaluated as “failed”, and when a deviation of 1 mm or more did not occur, it was evaluated as “pass”. .

[Example 1]
In Example 1, the web 12 was evaluated with a thickness of 40 μm, a conveyance speed of 50 m / min, and a conveyance tension of 100 N / m (see Table 1). In Example 1, evaluation of “pass” was obtained for all items (“wrinkles / sag”, “edge scratches”, “product scratches”, “meandering”).

[Example 2]
In Example 2, the thickness of the web 12 was 25 μm, the conveyance speed was 50 m / min, and the conveyance tension was 100 N / m (see Table 1). Also in Example 2, evaluation of “pass” was obtained for all items.

[Example 3]
In Example 3, the thickness of the web 12 was 16 μm, the conveyance speed was 50 m / min, and the conveyance tension was 100 N / m (see Table 1). Also in Example 3, evaluation of “pass” was obtained for all items.

[Example 4]
In Example 4, the thickness of the web 12 was 16 μm, the conveyance speed was 50 m / min, and the conveyance tension was 300 N / m (see Table 1). Also in Example 4, evaluation of “pass” was obtained for all items.

[Example 5]
In Example 5, the thickness of the web 12 was 16 μm, the conveyance speed was 50 m / min, and the conveyance tension was 30 N / m (see Table 1). Also in Example 5, evaluation of “pass” was obtained for all items.

[Example 6]
In Example 6, the web 12 was evaluated with a thickness of 16 μm, a conveyance speed of 100 m / min, and a conveyance tension of 30 N / m (see Table 1). As a result, also in Example 6, evaluation of “pass” was obtained for all items.

[Comparative Example 1]
Comparative Example 1 was evaluated with the web 12 having a thickness of 40 μm, a conveyance speed of 50 m / min, and a conveyance tension of 100 N / m (see Table 2). In Comparative Example 1, the evaluation for “product scratch” was “fail”.

[Comparative Example 2]
Comparative Example 2 was evaluated with the web 12 having a thickness of 25 μm, a conveyance speed of 50 m / min, and a conveyance tension of 100 N / m (see Table 2). In Comparative Example 2, the evaluation for “product scratch” was “fail”.

[Comparative Example 3]
Comparative Example 3 was evaluated with the web 12 having a thickness of 16 μm, a conveyance speed of 50 m / min, and a conveyance tension of 100 N / m (see Table 2). In Comparative Example 3, the evaluation for “product damage” was “fail”.

[Comparative Example 4]
Comparative Example 4 was evaluated with the web 12 having a thickness of 16 μm, a conveyance speed of 50 m / min, and a conveyance tension of 30 N / m (see Table 2). In Comparative Example 4, the evaluation for “product scratch” and “meander” was “fail”.

[Comparative Example 5]
Comparative Example 5 was evaluated with the web 12 having a thickness of 50 μm, a conveyance speed of 50 m / min, and a conveyance tension of 100 N / m (see Table 2). In Comparative Example 5, the evaluation for “edge flaw” was “fail”.

[Comparative Example 6]
Comparative Example 6 was evaluated with the web 12 having a thickness of 25 μm, a conveyance speed of 50 m / min, and a conveyance tension of 100 N / m (see Table 2). In Comparative Example 6, the evaluation for “wrinkles / sag” and “edge flaw” was “fail”.

[Comparative Example 7]
Comparative Example 7 was evaluated with the web 12 having a thickness of 16 μm, a conveyance speed of 50 m / min, and a conveyance tension of 100 N / m (see Table 2). In Comparative Example 7, the evaluation for “wrinkle / sag” and “edge flaw” was “fail”.

  As described above, according to the present invention, it was confirmed that “wrinkles / sag”, “edge scratches”, “product scratches”, and “meandering” can be prevented. Moreover, even if this invention was a comparatively thin case where the thickness of the web conveyed is less than 40 micrometers, it has confirmed that it functioned effectively (refer Examples 1-6). Furthermore, it has been confirmed that the present invention functions effectively even when the conveyance tension is relatively high such that the conveyance tension exceeds 100 N / m or when the conveyance tension is relatively low such that the conveyance tension is less than 100 N / m (Example). 4-6). In addition, it was confirmed that the present invention functions effectively even when the conveyance speed is relatively fast such that it exceeds 50 m / min (see Example 6).

10 Web Conveying Device 12 Web 16a Wet Film (Web)
16b Dry film (web)
19 Motor control unit (conveyance control unit, air amount control unit, air layer thickness control unit)
20, 31 Web guide device 21 Web guide roller 22 Inner cylinder 24 Outer cylinder 26 Blower control unit (air amount control unit, air layer thickness control unit)
27 Through hole 28 Air flow roller (non-contact support part)
29 Edge roller (contact support)
32 Main body (non-contact support)
50 Solution deposition equipment 52 Wet film (web)
59 Film (Web)

Claims (7)

In a web guide device for guiding the conveyance of the web in the longitudinal direction,
A pair of contact support portions that contact a peripheral surface with both sides of one side of the web and rotate as the web is conveyed;
Provided between one and the other of the pair of contact support portions, air is allowed to flow out from the outer peripheral surface to form an air layer between the outer peripheral surface and the web, and non-contacting via the air layer A non-contact support portion that supports the central portion in the width direction of the web in a state, and the outer peripheral surface is flush with the peripheral surface of the contact support portion;
A web guide device comprising:   The web guide device according to claim 1, wherein the non-contact support portion is formed of a porous member having air permeability.   The web guiding apparatus according to claim 2, wherein the porous member is at least one of a ceramic sintered body, a porous metal, and a porous plastic.   The web contact device according to claim 1, wherein the contact support portion is rotated by a frictional force with the web. A rotational force supply part for supplying rotational force to the contact support part;
The web guide device according to claim 1, wherein the contact support portion is rotated by a rotational force supplied from the rotational force supply unit.   The web guide device according to claim 1, wherein the web has a thickness of 40 μm or less. The web is spaced from the non-contact support at a predetermined spacing position;
The web guide device according to any one of claims 1 to 6, wherein the non-contact support portion causes the outflow air that flows out from the outer peripheral surface to flow out toward the web at the separation position.

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