JP2011235346A - Method for manufacturing band, and facility, and method of solution film forming - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a band with a larger width than before to manufacture a long film that has an uniform thickness and uniform optical properties, and a larger width than before.SOLUTION: In a method for manufacturing a band, a position detection device 34 detects a side edge 12e of a center member 12 that is a wide sheet material, and based on the detection result, first and second rollers 26, 27 control a conveyance passage of the center member 12. A third roller brings a side member 11, which is a narrow sheet member, into come closer toward the center member 12. Thereby, a butting position Pc where a side edge 11e of the side member 11 and the side edge 12e of the center member 12 are butted each other, is made to be positioned above a fourth roller 29. The side member 11 and the center member 12 butted each other, are sent to a welding device 42, and welded to each other in a longitudinal direction.

Description

  The present invention relates to a method and equipment for producing a band made of metal, which is used for a casting support for solution casting, and a solution casting method for producing a film using this band as a casting support.

  With the increase in the screen size of a liquid crystal display (LCD), an optical film used for the LCD is also required to have a large area. The optical film is manufactured in a long length and then cut into a predetermined size so as to correspond to the LCD. Therefore, in order to produce an optical film having a larger area, it is necessary to produce a longer optical film so that the width becomes larger.

  As a typical method for producing a long optical film, there is a continuous solution casting method. As is well known, the solution casting method is known in the art. A dope in which a polymer is dissolved in a solvent is cast on a running casting support and cast into a film, that is, a casting film. Is a method of producing a film by peeling the film from the casting support and drying it.

  A band made of metal is used as a casting support. The width of the film that can be produced is constrained by the width of this band, and a larger width band is required to produce a larger width film. However, until now, only bands with a width of up to about 2 m have been obtained.

  Therefore, in Patent Document 1, by welding a central band that is a central portion in the width direction and a pair of side bands that are each side portion of the band in the longitudinal direction, the width is 2200 mm, which is larger than the conventional one. I'm getting a band.

Korean Patent Publication No. 2009-0110082

  However, Patent Document 1 does not describe a specific method for welding the side band and the center band, and the obtained band is a quality problem in the welded portion between the side band and the center band. Is not sufficient as a casting support for solution casting. For example, even if solution casting is performed using this band, the cast film foams on the welded part, or the side region formed from the side band of the band warps, There is a problem that a film having a uniform thickness in the width direction cannot be produced. A film having a non-uniform thickness has non-uniform optical characteristics such as the direction of the optical axis.

  Therefore, the present invention aims to provide a manufacturing method and equipment for a band wider than the prior art, and further, using the obtained band, the thickness is uniform and the optical characteristics are uniform in the width direction. Another object of the present invention is to provide a solution casting method for producing a long film having a wide width.

  In order to solve the above-mentioned problems, the present invention is used as a casting support for solution casting, and in a method for manufacturing a band in which metal sheet materials are connected in a ring shape, a side portion that becomes a side portion of the band While transporting a sheet material and a central sheet material that is wider than the side sheet material and serves as a central portion in the width direction of the band, one side edge of the side sheet material and the central portion A butting step of abutting so that one side edge of the sheet material contacts, and a longitudinal welding step of welding in a longitudinal direction by a welding means while conveying the abutted side sheet material and the central portion sheet material; It has an annular welding process in which each front end and each rear end of the welded side sheet material and the central sheet material are welded to form an annular shape.

  In the longitudinal welding step, it is preferable to support the center sheet material and the side sheet material on the peripheral surface of the support roller disposed so as to face the welding means, and to weld on the support roller. Of the peripheral surface of the support roller, in the passage region where one side edge of the side sheet material and one side edge of the center sheet material pass, the center sheet material and the side sheet material It is more preferable that a high thermal conductivity portion made of a material having a higher thermal conductivity is formed.

  In the abutting step, one of the central sheet material and the side sheet material is brought into contact with and conveyed by a rotating roller that is arranged upstream of the welding means and rotates in the circumferential direction. It is preferable to control the orientation of the rotating roller in the longitudinal direction so that the distance is closer to the other.

  In the abutting step, the side sheet material conveyance path is formed so as to rotate in the circumferential direction so that the diameter gradually decreases from one end to the other end, and the one end faces the conveyance path for the central sheet material. It is preferable that the side sheet material is conveyed to the center sheet material by a taper roller disposed on the center roller.

  In the abutting step, it is preferable that the side sheet material is gripped by the gripping means that is displaced in the width direction of the center sheet material and the side sheet material is brought close to the center sheet material.

  A pair of belts are arranged so as to face the support rollers so as to be aligned in the longitudinal direction of the support rollers, and one of the pair of belts presses the central sheet material on the support rollers, and the other It is preferable to equalize the height at the welding position of the center sheet material and the side sheet material by pressing the side sheet material on the support roller. Preferably, the pair of belts is formed with a high heat conductive portion made of a material having a higher thermal conductivity than the center sheet material and the side sheet material.

  The contact position in the longitudinal direction of the support roller is detected by a detection means that is arranged upstream of the welding means and detects a contact position where the side sheet material and the central sheet material are in contact with each other. It is preferable to perform welding by displacing the welding means in the width direction of the support roller based on the conveyance speed of the partial sheet material and the central sheet material and the detected contact position.

  The longitudinal welding process includes a continuous welding process for continuously welding the side sheet material and the center sheet material, and an intermittent welding for intermittently welding the side sheet material and the center sheet material before the continuous welding process. It is preferable to have a welding process.

  It is preferable that the cleanliness of the welding position where the side sheet material and the center sheet material which are butted together are welded by the welding means is class 1000 or less in the US Federal Standard FED-STD-209D.

  It is preferable that the welded portion between the welded side sheet material and the central sheet material is heated by a heating means to remove the stress of the welded portion.

  Moreover, the present invention is used for a casting support for solution casting, and in a production facility for a band in which metal sheet materials are connected in a ring shape, one side of a side sheet material that becomes a side portion of the band. The side sheet material being conveyed so that an edge is wider than the side sheet material and is in contact with one side edge of the central sheet material which is the central portion in the width direction of the band It comprises a butting means for butting the center sheet material, and welding means provided downstream of the butting means and welding the supplied side sheet material and the center sheet material. Has been.

  The band manufacturing facility may be provided with a support roller that is arranged so as to face the welding means and supports the center sheet material and the side sheet material welded by the welding means on a peripheral surface. preferable. Of the peripheral surface of the support roller, in the passage region where one side edge of the side sheet material and one side edge of the center sheet material pass, the center sheet material and the side sheet material It is preferable that a high thermal conductivity portion made of a material having a higher thermal conductivity is formed.

  Further, in the present invention, a cast film is formed by continuously casting a dope in which a polymer is dissolved in a solvent on a transported support, and the cast film is formed from the cast support. In the solution casting method for forming a film by peeling and drying, the band manufactured by the above-described band manufacturing method is used as the casting support, and the upstream of the contact start position at which the dope starts to contact the band; The central portion sheet is pressed from the side of the surface of the one band on which the dope is cast by a roller that is rotatably provided downstream, and the side region formed from the side sheet material of the band is pressed. It is characterized by maintaining a height equal to the central region formed from the material.

  The casting support is dried while holding the casting film by a tenter having holding means for holding both sides of the casting film peeled off from the casting support and a drying means for drying the casting film. Of the cast film peeled off, it is preferable to cut off the side part peeled off from the side part region before guiding it to the tenter.

  A pair of wind shielding members that block the flow of gas are arranged so as to face each of the one side region and the other side region, and the gas is supplied between the pair of wind shielding members. By doing so, it is preferable to dry the casting membrane on the casting support.

  According to the band manufacturing method and equipment of the present invention, a band wider than the conventional band can be manufactured. Further, according to the solution casting method of the present invention, the obtained band is used to obtain a uniform thickness. A long film having a wider width than before can be produced.

It is a schematic side view of the manufacturing equipment of the band of the present invention. It is a schematic plan view of the band manufacturing equipment of FIG. It is a schematic side view of the welding unit which is another embodiment. It is a schematic plan view of the welding unit which is another embodiment. It is a partial cross section figure which follows the (V)-(V) line | wire of FIG. It is explanatory drawing of a weld bead and its periphery. It is the schematic of a taper roller. It is the schematic of a clip. It is the schematic of a band. It is the schematic of solution casting apparatus. It is the schematic of a band, a windshield, and a roller.

  The band used for the casting support for solution casting can be manufactured by the following band manufacturing equipment and method, but the following embodiment is an example of the present invention and does not limit the present invention.

  The band manufacturing equipment 10 shown in FIGS. 1 and 2 includes a side member 11 that becomes each side portion of the casting support and a central member 12 that becomes a central portion between one side portion and the other side portion. The long band member 13 is manufactured.

  The side member 11 and the central member 12 are metal sheet materials, respectively. The side member 11 is a narrow sheet material having a relatively narrow width, and the central member 12 is a wide sheet material having a relatively wide width. The side member 11 and the central member 12 are preferably made of stainless steel. The side member 11 and the central member 12 are preferably formed from the same material, and more preferably formed through the same raw material and forming process.

  As the central member 12, a band that has been used as a conventional casting support may be used. The central member 12 is wider than the side member 11, and the width of the central member 12 in this embodiment is constant in the range of 1500 mm to 2100 mm, and the width of the side member 11 is in the range of 50 mm to 500 mm. It is assumed to be constant.

  The band manufacturing facility 10 includes a delivery unit 16, a butting unit 17, a welding unit 18, a heating unit 19, and a winding device 20.

  The sending unit 16 includes a first sending device 23 that sends out the side member 11 and a second sending device 24 that sends out the central member 12, and sends the side member 11 and the central member 12 to the butting unit 17 independently. . The side member 11 wound in a roll shape is set in the first delivery device 23, and the side member 11 is unwound and sent to the butting portion 17. In the second delivery device 24, the central member 12 wound in a roll shape is set, and the central member 12 is unwound and sent to the butting portion 17.

  The abutting part 17 abuts the side member 11 and the central member that are independently guided so that the side edge 11e of the side member 11 and the side edge 12e of the central member 12 are in contact with each other. The abutting portion 17 includes a first roller 26 and a second roller 27 that are sequentially arranged on the conveyance path of the central member 12 from the upstream side, a third roller 28 that is disposed on the conveyance path of the side member 11, and the side member 11 and the central member. It is preferable to have the 4th roller 29 distribute | arranged to a conveyance path so that both of 12 may be supported.

  The fourth roller 29 is a butt that supports the sent side member 11 and the central member 12 at a butt position Pc where one side edge of the side member 11 and one side edge of the central member 12 start to contact each other. It is a support roller.

  The second roller 27 and the third roller 28 adjust the conveyance paths between the central member 12 and the side member 11 so that the central member 12 and the side member 11 are in contact with each other on the peripheral surface of the fourth roller 29.

  The 2nd roller 27 adjusts the conveyance path | route of the center member 12, and controls the passage path | route of the side edge 12e which should be welded with the side member 11 toward the abutting position Pc. The second roller 27 is provided with a shift mechanism 32 for displacing in the width direction Y of the central member 12. Between the second roller 27 and the fourth roller 29, there is position detecting means 34 for detecting the passing position of one of the side edges 12e of the central member 12 and sending a signal of the detected passing position to the controller 33. Arranged. The controller 33 obtains the displacement amount of the second roller 27 in the width direction Y based on the sent signal of the passing position, and sends the displacement amount signal to the shift mechanism 32. The shift mechanism 32 changes the inclination of the second roller 27 and the position of the second roller 27 in the width direction Y of the central member 12 based on the sent displacement amount signal. Thus, the central member 12 is displaced in the width direction Y by changing the inclination and position of the second roller 27.

  The first roller 26 is preferably provided with a shift mechanism 37. By this shift mechanism 37, the first roller 26 pushes the central member 12 toward the second roller 27 from one member surface. Depending on the amount of displacement of the first roller 26, the pressing force of the first roller 26 against the central member 12 changes, and the winding central angle of the central member 12 wound around the second roller 27 is adjusted by adjusting the pressing pressure. Can be controlled. By controlling the winding center angle, the amount of displacement of the central member 12 in the width direction Y by the second roller 27 can be controlled more precisely.

  The 3rd roller 28 adjusts the conveyance path of the side member 11, and adjusts the passage path of one side edge 11e which should be welded with the center member 12 toward the abutting position Pc. The third roller 28 is provided with a controller 38 that controls the orientation in the longitudinal direction. For example, the controller 38 moves the longitudinal direction of the third roller 28 to the side so that the angle θ1 formed by the circumferential direction in the contact area while in contact with the side member 11 and the transport direction X of the central member 12 changes. It changes along the member surface of the member 11.

  As described above, the first roller 26 to the third roller 28 are preferably controlled so that the butting position Pc is on the fourth roller 29. The first roller 26 to the third roller 28 are preferably drive rollers that rotate in the circumferential direction. By rotating in the circumferential direction, the first roller 26 and the second roller 27 also function as a transport unit for the central member 12, and the third roller 28 also functions as a transport unit for the side member 11. By using the first roller 26 to the third roller 28 as driving rollers, the control of the conveyance path between the side member 11 and the central member 12 becomes more reliable, and the first roller 26 between the side member 11 and the central member 12 becomes more reliable. The slip on the third roller 28 is prevented and the member surface is prevented from being damaged.

  In the above aspect, the conveyance path of both the side member 11 and the central member 12 is controlled so that the side member 11 and the central member 12 are close to each other. Only one transport path may be controlled. Further, instead of the first roller 26 and the second roller 27, the third roller 28 is arranged in the transport path of the central member 12, and the transport path of the central member 12 is changed by changing the longitudinal direction of the third roller 28. You may control.

  The abutting position Pc does not necessarily need to be on the fourth roller 29. For example, the butting position Pc may be on a welding support roller 41 described later. When the abutting position Pc is set on the welding support roller 41, the side member 11 with respect to the welding support roller 41 is arranged such that the upstream side in the rotation direction of the welding support roller 41 becomes the abutting position Pc from the welding position Pw to be welded. It is preferable to increase the winding central angle with the central member 12.

The welding unit 18 welds the side member 11 and the central member 12 supplied from the butt 29 in a state where the side edges 11e and 12e are in contact with each other. By being continuously supplied from the abutting portion 29, a longitudinal welding process of welding the side member 11 and the central member 12 in the longitudinal direction can be performed. The welding unit 18 includes a welding device 42. Examples of the welding device 42 include a laser welding device. As the laser welding apparatus, for example, a CO ₂ laser welding apparatus or a YAG laser welding apparatus can be used. In this embodiment, a case where a CO ₂ laser welding apparatus is used as the welding apparatus 42 will be described.

The welding device 42 emits the condensed laser light and irradiates the side member 11 and the central member 12 as irradiation targets with the laser light, thereby melting and joining the side member 11 and the central member 12. As shown in FIG. 1, the melting device 42 includes a laser oscillator 43, a welding apparatus body 46 that collects and emits laser light guided from the laser oscillator 43, and CO ₂ gas when irradiating the laser light. A gas supply unit (not shown). The CO ₂ gas prevents oxidation of the side member 11 and the central member 12. In FIG. 2, the illustration of the laser oscillator 43 is omitted to avoid complication of the drawing.

  A TIG welding (Tungsten Inert Gas welding) apparatus may be used instead of the laser welding apparatus. As is well known, TIG welding is one type of welding arc welding that uses an arc as a heat source, and is a type of inert gas arc welding that uses inert gas (inert gas) as a shielding gas and tungsten or a tungsten alloy as an electrode. is there. Laser welding is more preferable than TIG welding. Moreover, it is good also as hybrid welding which combined TIG welding and laser welding.

  A welding support roller 41 for supporting the side member 11 and the central member 12 on the circumferential surface is provided in the conveyance path between the side member 11 and the central member 12 so as to face the laser beam exit of the welding apparatus main body 46. is there. The welding support roller 41 is arranged so that the longitudinal direction thereof coincides with the width direction Y of the side member 11 and the central member 12. The support position of the side member 11 and the central member 12 by the welding support roller 41 is set so that the side member 11 and the central member 12 while being supported by the peripheral surface of the welding support roller 41 are irradiated with laser light. It is preferable to do. That is, it is preferable to perform welding on the welding support roller 41. Thereby, the side member 11 and the central member 12 are stabilized in a state in which the side edges 11e and 12e are in contact with each other, and the laser beam can be reliably irradiated to the portion to be irradiated.

  The welding apparatus body 46 is preferably provided with a shift mechanism 50 for displacement in the width direction Y. The contact position Ps (see FIG. 5) where the side edge 11e of the side member 11 and the side edge 12e of the central member 12 are in contact is detected upstream of the welding device 42, and the detected contact position Ps (see FIG. 5). Position detecting means 47 for sending the above signal to the controller 51 is provided. The position detecting means 47 only needs to be disposed in the vicinity of the conveyance path from the butting position Pc to the welding device 42.

  The controller 51 obtains the displacement amount of the welding apparatus main body 46 in the width direction Y based on the sent signal of the contact position Ps (see FIG. 5), and sends the displacement amount signal to the shift mechanism 50. When the conveyance speed signal between the side member 11 and the central member 12 is input, the controller 51 sends a displacement timing signal together with a displacement timing signal to the displacement mechanism 50 to the displacement mechanism 50. The shift mechanism 50 changes the position of the welding apparatus main body 46 at a predetermined timing based on the received displacement amount and displacement timing signal. Thus, by changing the position of the welding apparatus main body 46 in the width direction Y, the irradiation position of the laser beam is controlled more precisely, and the side member 11 and the central member 12 are more reliably welded. In addition, the conveyance speed of the side member 11 and the central member 12 to the welding apparatus 42 in this embodiment is set as a range of 0.15 m / min or more and 20 m / min or less.

  As shown in FIG. 1, the welding unit 18 is more preferably provided with a chamber 52 that partitions the welding device main body 46 and the welding support roller 41 from the external space, and a cleaning device 55 that cleans the gas. In FIG. 2, the illustration of the chamber 52 and the cleaning device 55 is omitted to avoid complication of the drawing. The chamber 52 is provided with a first opening (not shown) for letting out the internal gas to the outside and a second opening (not shown) for guiding the gas cleaned by the cleaning device 55 to the inside. The first opening and the second opening are each connected to the cleaning device 55. The gas inside the chamber 52 is guided to the cleaning device 55 from the first opening, and the cleaning device 55 cleans the gas guided from the chamber 52 and sends it to the chamber 52 through the second opening. In this way, the internal gas of the chamber 52 is circulated with the cleaning device 55.

  By cleaning the internal gas of the chamber 52, the welding position Pw and its periphery are cleaned, and foreign matter and the like are prevented from being mixed into the welded portion 13w. Note that, by keeping the pressure inside the chamber 52 higher than the pressure in the external space, the inside of the chamber 52 can be reliably held in a clean state. Further, by setting the welding position Pw to a relatively high position with respect to the delivery unit 16, the butting unit 17, the heating unit 19, and the winding device 20, it is possible to further prevent foreign matters from being guided from these positions. it can.

  The cleanliness inside the chamber 52 is preferably, for example, class 1000 or less, more preferably class 100 or less, according to the US Federal Standard FED-STD-209D.

  A heating unit 19 is preferably provided downstream of the welding unit 18. The heating part 19 will not be specifically limited if it heats the welding part 13w of the band member 13 obtained by welding so that it may become a fixed temperature range. Stress as distortion caused by welding may remain inside the welded part 13w and its periphery, and the stress can be removed by heating the welded part 13w by the heating part 19. By removing the stress, it becomes more reliable to prevent deformation during continuous use in solution casting.

  The temperature of the welded part 13w due to heating of the heating part 19 is not particularly limited as long as the stress is removed, but when the band member 13 is made of stainless steel, for example, the temperature of the welded part 13w is preferably 100 ° C. Heating is preferably performed in a range of 200 ° C. or lower, more preferably 120 ° C. or higher and 180 ° C. or lower.

  As the heating unit 19, for example, there is a blowing means. As shown in FIG. 1, the blowing means as the heating unit 19 includes a duct 56 that blows out a gas having a constant temperature, and a blower 57 that sends the gas to the duct 56 after controlling the temperature of the gas. In FIG. 2, the illustration of the duct 56 and the blower 57 is omitted to avoid complication of the drawing.

  The heating unit 19 may be provided on the opposite side of the welding support roller 41 as shown in FIG. 1 with respect to the conveyance path of the band member 13 or may be provided on the same side as the welding support roller 41.

  The band member 13 from which the stress has been removed is sent to the winding device 20 downstream of the heating unit 19 and wound up in a roll shape. In the winding device 20, a winding core for winding the band member 13 is set, and driving means for rotating the winding core in the circumferential direction is provided.

  The winding device 20 also functions as a welding tension control means for controlling the tension between the band member 13, the side member 11, and the central member 12 at the welding position Pw. Therefore, it is preferable to control the torque of the winding device 20 so that the tension between the band member 13, the side member 11, and the central member 12 at the welding position Pw is kept constant. Thereby, the band member 13 with which the aspect of the welding part 13w is more uniform in a longitudinal direction can be obtained.

  When starting welding, it is preferable to use the winding device 20 as follows, for example. First, the side member 11 and the central member 12 are set on the conveyance path from the delivery unit 16 to the winding device 20, and the respective ends of the side member 11 and the central member 12 are wound around the winding core of the winding device 20. Winding of the side member 11 and the central member 12 is started. Winding is started, the conveyance path between the side member 11 and the central member 12 is controlled, and the butting position Pc is held at a predetermined position. After the abutting position Pc between the side member 11 and the central member 12 is kept constant, welding is started by the welding device 42.

  It is preferable to perform welding while suppressing the deviation of the side member 11, the central member 12, and the band member 13. For example, instead of the welding unit 18, a welding unit 61 as shown in FIGS. 3 and 4 provided with a pressing device may be used. The welding unit 61 further includes a pressing device 62 in addition to the welding unit 18 shown in FIGS. 1 and 2, and includes a shift mechanism 50, a controller 51, a chamber 52, and a cleaning device 55 in the same manner as the welding unit 18. In order to avoid complication of illustration, these illustrations are omitted in FIGS. 1 and 2 are denoted by the same reference numerals as those in FIGS. 1 and 2 and description thereof is omitted. In the welding unit 61, the chamber 52 surrounds the pressing device 62 and the welding support roller 42 so as to partition from the external space.

  The pressing device 62 suppresses the displacement of the side member 11, the central member 12, and the band member 13 at the welding position Pw, and is supported by a pair of belts including a first belt 63 and a second belt 64. The side member 11, the central member 12, and the band member 13 on the roller 41 are pressed.

  The first belt 63 and the second belt 64 are endless belts formed in an annular shape. The first belt 63 and the second belt 64 are wound around the circumferential surfaces of the fifth roller 67 to the seventh roller 69 so as to be aligned in the longitudinal directions of the fifth roller 67 to the seventh roller 69. At least one of the fifth roller 67 to the seventh roller 69 is a drive roller that rotates in the circumferential direction. Due to the rotation of the driving roller, the first belt 63 and the second belt 64 are conveyed while maintaining a conveyance path parallel to each other.

  The fifth roller 67 to the seventh roller 69 are arranged so that their longitudinal directions coincide with the longitudinal direction of the welding support roller 41.

  The fifth roller 67 to the seventh roller 69 are arranged in a region opposite to the side on which the fourth roller 29 and the welding support roller 41 are arranged with respect to the conveyance path between the side member 11 and the central member 12. . The fifth roller 67 is provided so as to face the conveyance path between the side member 11 and the central member 12 from the fourth roller 29 toward the welding support roller 41. The sixth roller 68 is provided so as to face the conveyance path between the side member 11 and the central member 12 from the welding support roller 41 toward the heating unit 19. The seventh roller 69 is appropriately arranged so as to determine the conveyance path of the first belt 63 and the second belt 64 from the sixth roller 68 to the fifth roller 67.

  The fifth roller 67 and the sixth roller 68 are the first belt 63 and the second belt 64 that are directed from the fifth roller 67 to the sixth roller 68, and the side member 11, the central member 12, and the band on the welding support roller 41. It arrange | positions so that it may convey so that the member 13 may be pressed. For example, when the side member 11 and the central member 12 on the welding support roller 41 are welded from above, the lower end of each of the fifth roller 67 and the sixth roller 68 is higher than the upper end of the welding support roller 41. Also, it is arranged to be in a low position.

  The fifth roller 67 and the sixth roller 68 are arranged so that the conveyance path of the first belt 63 faces the conveyance path between the side member 11 and the side portion 13s of the belt member 13 formed from the side member 11, and The transport path of the second belt 64 is provided so as to face the transport path between the central member 12 and the central portion 13 c of the belt member 13 formed from the central member 12. Accordingly, the first belt 63 presses the side member 11 and the side portion 13e, and the second belt 64 presses the center member 12 and the middle portion 13c to the welding support roller 41, respectively.

  As described above, the first belt 63 and the second belt 64 are provided to face the welding support roller 41, respectively, so that the heights of the side member 11 and the central member 12 at the welding position Pw are equal. Press. The height of the side member 11 and the central member 12 is the height of the exposed surface of each member 11, 12. By pressing the side member 11 and the central member 12 so that the heights are equal to each other and performing welding in this state, the aspect of the welded portion 13w becomes more uniform in the longitudinal direction and welding is more reliably performed. Can be done.

  The longitudinal welding process will be described in more detail with reference to FIGS. The first belt 63 and the second belt 64 are transported at intervals. The conveyance path is set so that the welding position Pw passes through the gap between the first belt 63 and the second belt 64 between the first belt and the second belt 64. Thereby, the contact position Ps at which the side edge 11e of the side member 11 and the side edge 12e of the central member 12 are in contact with each other passes through the gap between the first belt 63 and the second belt 64, as shown in FIG. Welding is performed between the first belt 63 and the second belt 64. In addition, illustration of the welding apparatus main body 46 is abbreviate | omitted in FIG.

  The distance D1 between the first belt 63 and the second belt 64 is preferably in the range of 6 mm to 12 mm. In the cross section in the width direction Y between the side member 11 and the central member 12, the distance D2 between the contact position Ps and the first belt 63 and the distance D3 between the contact position Ps and the second belt 63 are 3 mm or more and less than 6 mm, respectively. It is preferable to set it as the range.

  Instead of the pressing device 62, rollers (not shown) may be arranged upstream and downstream of the welding device main body 46 so that the longitudinal direction coincides with the longitudinal direction of the welding support roller 41. In this case, the side member 11 and the central member 12 at the welding position Pw can be pressed by pressing the side member 11 and the central member 12 with one upstream roller and pressing the band member 13 with the other downstream. it can.

  As shown in FIG. 6, a weld bead 72 is formed at the contact position Ps and the periphery thereof by melting by the heat of the welding device 42. Heat is transmitted from the weld bead 72 to both sides, and a heat-affected region is generated in each of the side member 11 and the central member 12 that is affected by heat in welding. This heat-affected region may immediately show different properties from other regions that are not affected by heat, or may show over time. For example, when a material having such a wide thermal influence is used as a casting support, the casting film may be deformed or the casting film may be foamed while the solution casting is continuously performed.

  Therefore, as shown in FIG. 5, in the peripheral region of the welding support roller 41, a high heat conduction portion made of a material having higher heat conductivity than the side member 11 and the central member 12 is in a passage region through which the contact position Ps passes. 71 is preferably formed. Thereby, the heat from the welding apparatus 42 (refer FIG. 3, FIG. 4) can be spread | diffused more quickly. In order to diffuse heat more quickly on the side of the welding support roller 41, the width of the heat affected area 73 between the side member 11 and the central member 12 can be made smaller or the depth of the heat affected area 73 can be made shallower.

  It is preferable that the width D4 of the passage region used as the high heat conducting portion 71 is in a range of 26 mm or more and 32 mm or less.

  Furthermore, it is more preferable that high heat conductive portions made of a material having higher heat conductivity than the side member 11 and the central portion 12 are formed on both surfaces of the first belt 63 and the second belt 64. Thereby, the width | variety of the heat affected zone 73 can be made smaller or the depth can be made shallower.

  It is preferable that the side edge 11e of the side member 11 and the side edge 12e of the central member 12 are in close contact with each other so that the gap is 0 (zero) at the welding position Ps. Therefore, it is preferable that the side member 11 and the central member 12 are formed in advance so as not to generate a gap when the side edges 11e and 12e are brought into contact with each other. Thereby, the band member without a space | gap in a welding part can be manufactured more reliably.

  The above-described longitudinal welding process may be only a continuous welding process in which welding is continuously performed in the longitudinal direction of the side member 11 and the central member 12, and in addition to this, intermittent welding in which welding is intermittently performed. A welding process may be performed. When intermittently welding, the side member 11 and the central member 12 that are continuously sent to the welding device 42 are welded intermittently. Such an intermittent welding process may be performed before the continuous welding process. In this case, in the intermittent welding process, first, the side member 11 and the central member 12 may be temporarily joined, and then joined over the entire longitudinal direction in the continuous welding process.

  When temporary joining is performed in the intermittent welding process, and then joining is performed in the continuous welding process, the side member 11 and the central member 12 are guided from the butt portion 17 (see FIGS. 1 and 2) to the welded portion 18 to be intermittent. Welding. In addition, when the side member 11 and the central member 12 are provided with a surface corresponding to a casting surface when used as a subsequent casting support and a back surface corresponding to a non-casting surface, intermittent The welding in the welding process is preferably performed on the back surface. Then, the side member 11 and the central member 12 are conveyed so that a back surface may pass facing the welding apparatus main body 46 (refer FIG. 1).

  After performing intermittent welding, it guides to the winding device 20 and winds up. In addition, you may heat with the heating part 19 with respect to a welding part before winding. A temporary joining member (not shown) composed of the side member 11 and the central member 12 wound up through the intermittent welding process is unwound by a feeding device (not shown) and sent again to the welded portion 18. This feeding is performed so that the surface of the temporary welding member passes facing the welding apparatus main body 46 (see FIG. 1). The welding part 18 performs continuous welding to obtain the band member 13. Instead of this method, the two welded portions 18 are arranged relatively upstream and downstream, intermittent welding is performed at one upstream welded portion 18, and continuous welding is performed at the other downstream welded portion 18. May be implemented.

  When welding is performed, the weld bead 73 may be formed to be higher than the side member 11 and the central member 12. Therefore, as shown in FIG. 5, the welding support roller 41 used in the case where the first process of welding one surface in the longitudinal direction and the second process of welding the other surface in the longitudinal direction are performed as shown in FIG. In addition, it is preferable that a groove 76 is formed in a passing region through which the contact position Ps passes. It is good to carry out the 2nd process by conveying the side member 11 and the central member 12 so that the welding part formed from the welding beat 73 swelled at the 1st process may pass this groove | channel 76. FIG. Thereby, the band member 13 that is smoother and has less residual stress can be obtained. Therefore, even when used in solution casting, it is possible to more reliably produce a film in which the band as a casting support is less deformed and changes in properties, the casting membrane does not foam, and the thickness is not uneven.

  The width D5 of the groove 76 is preferably in the range of 6 mm to 12 mm, and the depth D6 of the groove may be about 1 mm.

  In the above embodiment, the third roller 28 is used as means for adjusting the conveyance path of the side member 11 in the abutting portion 17, but instead of the third roller 28, a tapered roller 81 as shown in FIG. 7 may be used. The taper roller 81 is a roller having a circular cross section formed so that the diameter d continuously decreases gradually from one end to the other end. The diameter d gradually decreases gradually from one end to the other end at a constant rate. A taper roller is disposed so that one end with a large diameter d is directed toward the conveyance path of the central member 12 and the other end with a small diameter d is directed to the side opposite to the central member 12.

  The side member 11 being conveyed comes into contact with the taper roller 81, thereby changing the conveyance path to the direction of the arrow A toward the central member 12, and approaching the central member 12. Thereby, the side member 11 is reliably conveyed toward butting position Pc (refer FIG. 1, FIG. 2).

  The taper roller 81 is preferably provided with driving means 82 that rotates in the circumferential direction. The rotating shaft is formed through the center of one end surface and the center of the other end surface. By conveying the side member 11 by the taper roller 81 rotated by the driving means 82, the side member comes closer to the central member 12 more effectively.

  Instead of the third roller 28, a clip 85 as gripping means as shown in FIG. 8 may be used. The clip 85 includes a clip body 86 opened in a U-shape and a pair of sandwiching pins 87 provided at the respective distal end portions of the clip body 86, and grips and holds the side member 11. The pinching pin 87 is provided so as to be movable between a pinching position for pinching the side member 11 and a retreating position for retreating from the pinching position. The clip 85 includes a moving mechanism 88 and is movable between a grip start position where gripping is started and a grip release position where gripping is released. The clip 85 is also movable in the width direction Y.

  The clip 85 grips the side member 11 when the pinching pin 87 moves to the pinching position at the gripping start position. The clip 85 is conveyed downstream while approaching the direction A toward the central member 12 with the side member 11 being gripped.

  The taper roller 81 and the clip 85 may be used to bring the central member 12 closer to the side member 11 in addition to being used to bring the side member 11 closer to the central member 12. In this case, the central member 12 may be supported or conveyed by the taper roller 81 and the clip 85.

  In the above embodiment, the both side members 11 are welded to the central member 12 at the same time. However, after the one side member 11 is welded to the central member 12, the other side member 11 may be welded to the central member 12. .

  As shown in FIG. 9, a band 91 used as a casting support is an endless band formed into an annular shape. Therefore, the obtained band member 13 is cut to a predetermined length, and the band member 13 cut to a predetermined length is welded at the front end and the front end in the longitudinal direction to manufacture the band 91. In the case where the band member is formed from the side member 11 and the central member 12 that have been cut to a predetermined length in advance, the cutting step is not necessarily performed.

  The band member 13 is preferably cut in a direction crossing the width direction Y. More preferably, the cut direction is such that the angle formed with the width direction Y is in the range of approximately 5 ° to 15 °. The angle θ2 formed by the welded portion 91w in which the front end and the front end in the longitudinal direction of the band member 13 thus cut are welded and the width direction Y is approximately in the range of 5 ° to 15 °. As described above, in the annular welding process in which the long band member 13 is annular, the welding apparatus 42 used in the longitudinal welding process may be used, or other known welding apparatuses may be used.

  The band 91 manufactured by welding includes a side portion 91s formed from the side member 11 (see FIGS. 1 to 8) and a center portion 91c formed from the central member 12 (see FIGS. 1 to 8). . The width of the band 91 thus obtained is in the range of 2000 mm to 3000 mm.

  The obtained band 91 is used for a solution casting apparatus after the surface is polished to a mirror surface. A method for producing a film using the band 91 will be described below. The kind of polymer is not particularly limited, and a known polymer that can be formed into a film by solution casting may be used. In the following embodiments, a case where cellulose acylate is used as a polymer will be described as an example.

  As shown in FIGS. 10 and 11, the solution casting apparatus 110 forms a film for forming a cellulose acylate film (hereinafter, simply referred to as “film”) 116 from a dope 113 in which cellulose acylate 111 is dissolved in a solvent 112. An apparatus 117; a first slitter 118 that cuts out each side of the film 116; a first tenter 120 that advances drying while holding each side of the film 116 with a holding means 119; and a plurality of rollers 118 that hold the film 116 with a plurality of rollers 118. A roller drying device 124 that dries while supporting, a second tenter 125 that holds each side portion of the film 116 with holding means, and applies a tension in the width direction to the film 116, and a second tenter 125. A second slitter 126 for cutting off the holding marks on the respective sides held by the holding means, and the film 116. Wound on the winding core and a winding device 127 for the roll, in order from the upstream. In FIG. 11, the illustration of the duct 141 is omitted to avoid complication of the drawing. In the present specification, the solvent content (unit:%) is a value based on the dry weight. Specifically, when the mass of the solvent is x and the mass of the film 116 is y, {x / (Y−x)} × 100.

  The film forming apparatus 117 includes a pair of rollers 131 and 132 that rotate in the circumferential direction. A band 91 is wound around the circumferential surfaces of the rollers 131 and 132. At least one of the rollers 131 and 132 may be a driving roller having a driving unit. As the drive roller rotates in the circumferential direction, the band 91 in contact with the circumferential surface is conveyed.

  A casting die 133 that flows out of the dope 113 is provided above the band 91. By continuously flowing out the dope 113 from the casting die 133 to the band 91 being conveyed, the dope 113 is cast on the band 91 to form a casting film 136. The casting die 133 may be provided above the band 91 on the one roller 131, or may be provided above the band 91 from the one roller 131 toward the other roller 132. In the latter case, a roller (not shown) may be disposed between one roller 131 and the other roller 132, and the band 91 may be supported by this roller.

  Regarding the dope 113 from the die 31 to the band 91, that is, a so-called bead, a decompression chamber is provided upstream in the traveling direction of the band 91, but the illustration is omitted. The decompression chamber sucks the atmosphere in the area upstream of the dope 113 that has flowed out to decompress the area.

  The cast film 136 is hardened to such an extent that it can be conveyed to the first tenter 120, and then peeled off from the band 91 in a state containing a solvent. At the time of stripping, the film 116 is supported by a stripping roller (hereinafter referred to as stripping roller) 137, and the stripping position where the casting film 136 is stripped from the band 91 is kept constant. The stripping roller 137 may be a driving roller that includes driving means and rotates in the circumferential direction.

  The film forming apparatus 117 includes three ducts of a first duct 141, a second duct 142, and a third duct 143 that send the dried gas toward the casting film 136 in order from the upstream side along the traveling path of the band 91. Is provided. However, the number of ducts is not limited to three.

  In the first duct to the third ducts 141 to 143, a plurality of outlets (not shown) through which the dried gas flows out are formed facing the traveling path of the band 91. Each outlet has a slit shape extending in the width direction of the band 91. However, the shape of the outlet is not limited to this.

  The first duct to the third ducts 141 to 143 are each connected to a blower (not shown), and the gas supplied from the blower flows out from the outlet. A blower controller (not shown) that independently controls the temperature, humidity, and flow rate of the gas supplied to each of the first duct to the third ducts 141 to 143 is connected to the blower. The casting membrane 136 is dried by the outflow of gas through the first to third ducts 141 to 143.

  The gas from the first to third ducts 141 to 143 is heated hot air, and the casting film 136 is heated by this hot air. The temperature of the casting film 136 is adjusted by controlling the temperature and flow rate of the hot air and controlling the temperatures of the rollers 131 and 132 (described later).

  Each of the rollers 131 and 132 includes a first controller (not shown) and a second controller (not shown) that control the peripheral surface temperature to a predetermined temperature.

  In order to dry the casting membrane 136, in this embodiment, a drying means including the first to third ducts 141 to 143 is used. However, the drying means is not limited to this, and other drying means may be used according to the properties of the casting film 136 and its change with time. As another drying means, for example, there is a drying means including a condenser, which may be replaced with or added to the drying means including the first to third ducts 141 to 143.

  The first duct 141 is provided with a pair of wind shields 146 extending in the longitudinal direction of the band 91 so as to face the side portion of the casting film 136. The wind shielding plate 146 is arranged on the outer side in the width direction of the band 91 than the welded portion 91 w of the band 91. By arranging the wind shield plate 146 so as to face the side portion 91s of the band, the welded portion 91w is located on the inner side in the width direction of the band 91 than the wind shield plate 146. Accordingly, the dry gas from the first duct 141 is blocked from flowing on the side portion 91s of the band 91, thereby preventing the side portion 91s from being deformed by the heat of the dry gas. For example, the side portion 91 s is prevented from being deformed so as to float from the rollers 131 and 132.

  Note that the pair of wind shielding plates 146 may also be provided in the second duct 142 and the third duct 143.

  The contact start position at which the dope 113 starts to contact the band 91 is a position at which the casting film 136 starts to be formed. A pair of rollers 147 is disposed on the side upstream of the contact start position. The pair of rollers 147 is arranged so as to face the side portion 91 s of the band, and the longitudinal direction thereof coincides with the width direction of the band 91. Similarly, a pair of rollers 147 is arranged on the downstream side of the contact start position. By pressing the side portion 91s with these rollers 147, the side portion 91s can be more reliably prevented from being lifted.

  The roller 147 is preferably a driving roller that is rotated by driving means. By rotating at the same speed as the transport speed of the band 91, generation of frictional heat of the side portion 91s due to contact between the band 91 and the roller 147 can be suppressed, and deformation of the side portion 91s can be more reliably prevented. Can do.

  In the present embodiment, the pair of rollers 147 are arranged both upstream and downstream of the contact position, but either one of the upstream and downstream may be used.

  The length of the outlet 133a which is the slit shape of the casting die 133 is longer than the width of the central portion 91c of the band 91, and the casting film 136 may be formed also on the side portion 91s. This is because the side part of the cast film 136 formed on the welded part 91w and the side part 91s can be cut off by the first slitter 118 or the second slitter 126. If the band 91 manufactured according to the present invention is used without being cut, the casting film 136 is prevented from foaming on the welded portion 91w and the side portion 91s. Therefore, the first slitter 118 or the second slitter 118 is not necessarily used. The slitter 126 may not be excised. However, the side part of the cast film 136 formed on the welded part 91w and the side part 91s can be cut off by the first slitter 118 upstream of the first tenter 120 after being peeled off from the band 91. preferable.

  A blower (not shown) may be disposed on the conveyance path between the film forming apparatus 117 and the first tenter 120. The film 116 is dried by the air blown from the blower.

  The cast film 136 is peeled off by the peeling roller 137. The cast film 136 that has been peeled off, that is, the film 116 is guided to the first tenter 120. The holding means 119 of the first tenter 120 is a clip.

  The first tenter 120 applies tension in the width direction (hereinafter referred to as direction B) while holding the film 116 by the holding means 110 and transporting the film 116 in the longitudinal direction (hereinafter referred to as direction A). Increase the width of In the first tenter 120, a preheating area, an extension area, and a relaxation area are formed in this order from the upstream side. There may be no relaxation area.

  The first tenter 120 includes a pair of rails (not shown) and a chain (not shown). The rails are installed on both sides of the conveyance path of the film 116, and the pair of rails are arranged at a predetermined interval. This rail interval is constant in the preheating area, gradually increases in the extending area as it goes downstream, and is constant in the relaxation area. In addition, you may make it the rail space | interval of a relaxation area become narrow gradually as it goes downstream.

  The chain is stretched over a driving sprocket and a driven sprocket (not shown), and is attached so as to be movable along the rail. The plurality of holding means 119 are attached to the chain at a predetermined interval. Due to the rotation of the driving sprocket, the holding means 119 circulates along the rail.

  The holding means 119 starts holding the guided film 116 in the vicinity of the inlet of the first tenter 120, moves toward the outlet, and releases the holding in the vicinity of the outlet. The holding means 119 whose release has been released moves again to the vicinity of the entrance, and holds the newly guided film 116.

  The preheating area, the stretching area, and the relaxation area are formed as spaces by sending dry air from the duct 151 and do not have a clear boundary. The duct 151 is provided above the conveyance path of the film 116. The duct 151 has a slit for sending dry air, and is supplied from a blower (not shown). The blower sends dry air adjusted to a predetermined temperature and humidity to the duct 151. The duct 151 is arranged so that the slit faces the conveyance path of the film 116. Each slit has a shape extending in the width direction of the film 116 and is formed at a predetermined interval in the transport direction. Note that a duct having a similar structure may be provided below the conveyance path of the film 116, or may be provided both above and below the conveyance path of the film 116.

  While the film is being transported by the first tenter 120, drying is promoted by the drying air from the duct 151, and the width can be changed at a predetermined timing by the holding means 119.

  The solvent content of the film 116 in the stretching area is preferably 2% by mass or more and 250% by mass or less, and more preferably 2% by mass or more and 100% by mass or less. The stretching ratio ER1 (= {(width after stretching) / (width before stretching)} × 100) in the stretching treatment is preferably greater than 100% and 140% or less. The temperature of the film 116 in the stretching process is preferably 95 ° C. or higher and 150 ° C. or lower.

  The atmosphere inside the roller dryer 124 is adjusted by an air conditioner (not shown) such as temperature and humidity. The roller drying device 124 is provided with a number of rollers 156, and the film 116 is wound around and conveyed. The solvent evaporates from the film 116 in the roller drying device 124. In the roller drying device 124, it is preferable to perform the drying process until the solvent content becomes 5% by mass or less.

  When the film 116 coming out of the roller drying device 124 is curled, a curl correcting device (not shown) that corrects the curl and flattens the film 116 between the roller drying device 124 and the second tenter 125. None) may be provided.

  The second tenter 125 stretches the film 116. By this stretching, the film 116 having desired optical properties is obtained. The obtained film 116 can be used as a retardation film. The second tenter 125 has the same structure as the first tenter 33. The duct 157 provided in the second tenter 125 flows from the slit (not shown) out of the drying air heated to a predetermined temperature and flows toward the film 116.

  The holding means 160 of the second tenter 125 is also a clip like the first tenter 120.

  The stretching ratio ER2 (= {(width after stretching) / (width before stretching)} × 100) in stretching in the second tenter 125 is preferably greater than 105% and not greater than 200%, and is not less than 110% and not greater than 160. % Or less is more preferable. The solvent content of the film 116 at the start of stretching is preferably 5% by mass or less, and more preferably 3% by mass or less. The temperature of the film 116 in stretching is preferably 100 ° C. or higher and 200 ° C. or lower.

  The second tenter 125 may not be used depending on the optical characteristics of the film 116 to be manufactured.

  When the film 116 is guided, the second slitter 126 downstream of the second tenter 125 cuts out the side portion including the retention marks by the holding means 119 and 158 of the first tenter 120 and the second tenter 125. The film 116 with the side portions cut off is sent to the winding device 127 and wound into a roll.

  A cooling device (not shown) may be provided between the second tenter 125 and the second slitter 126 to cool the film 116 from the second tenter 125 and lower the temperature.

  The cellulose acylate 111 is not particularly limited. The cellulose acylate 111 may have only one type of acyl group, or may have two or more types of acyl groups. When there are two or more acyl groups, one of them is preferably an acetyl group. The ratio in which the hydroxyl group of cellulose is esterified with carboxylic acid, that is, the substitution degree of the acyl group satisfies all of the following formulas (I) to (III) is preferable. In the following formulas (I) to (III), A and B represent the substitution degree of the acyl group, A is the substitution degree of the acetyl group, and B is the substitution degree of the acyl group having 3 to 22 carbon atoms. It is.

(I) 2.0 ≦ A + B ≦ 3.0
(II) 1.0 ≦ A ≦ 3.0
(III) 0 ≦ B ≦ 2.0

  The total substitution degree A + B of the acyl group is more preferably 2.20 or more and 2.90 or less, and particularly preferably 2.40 or more and 2.88 or less. Further, the substitution degree B of the acyl group having 3 to 22 carbon atoms is more preferably 0.30 or more, and particularly preferably 0.5 or more. Among these, the present invention is particularly effective when cellulose diacetate (DAC) is used as the cellulose acylate 111.

  Examples of the present invention will be described below. However, the present invention is not limited to the following examples, and the following examples are given as examples of the present invention. Details will be described in the first embodiment, and only the conditions different from the first embodiment will be shown for each of the second and following embodiments and the comparative example for the present invention.

  The side member 11 and the central member 12 are formed of SUS316. The width of the side member 11 is 200 mm, and the width of the central member 12 is 2000 mm. The side member 11 and the central member 12 have a length of 120 m and a thickness of 1.5 mm. The side member 11 and the central member 12 have a front surface that is a mirror surface and a back surface that is not a mirror surface. In addition, before welding, the side member 11 and the central member 12 wiped off dust and moisture with a solvent, and cleaned the side edges 11e and 12e to be welded.

The welding device 42 is a CO ₂ laser welding device. The laser output was 1 kW, and the conveying speed between the side member 11 and the central member 12 guided to the welding device 42 was 1 m / min.

  First, welding was performed from the back surface using the band manufacturing facility 10. However, in the present Example 1, the welding support roller 41 in which the high heat conduction part 71 is not formed was used. Further, the position detecting means 47 and the heating unit 19 are not used. The pressing device 62 shown in FIGS. 3 and 4 is not used. The first delivery device 23 is such that the surface of the side member 11 is in contact with the third roller 28 and the fourth roller 29, and the surface of the central member 12 is in contact with the first roller 26, the second roller 27, and the fourth roller 29. Then, the side member 11 and the central member 12 were sent out from the second delivery device 24.

  The conveyance path was set by controlling the conveyance path of the central member 12 by the position detection means 34 and the second roller 27. The angle θ1 formed by the circumferential direction in the contact region of the third roller 28 that is in contact with the side member 11 and the transport direction X of the central member 12 was 5 °. With the third roller 28, the conveyance path of the side member 11 is controlled to determine the conveyance path. In this way, the butting position Pc is set on the fourth roller 29.

  The side member 11 and the central member 12 were sent from the fourth roller 29 to the welding unit 18, and the back surface was continuously welded. The band member 13 composed of the welded side member 11 and the central member 12 was once wound around the winding device 20.

  The roll-shaped band member 13 was sent again from the delivery device (not shown) to the welding unit 18 to continuously weld the surface. The welding support roller 41 used for surface welding has a groove 76 with a width D5 of 8 mm.

  With respect to the welded portion 13w extending in the longitudinal direction, a deviation amount (unit: mm) in the width direction Y and a deviation amount (unit: mm) in the thickness direction were measured. That is, the shift amount in the thickness direction is a difference in height between the center 13c at the welded portion 13w and the side portion 13s. Over a length of 120 m, the amount of deviation in the width direction Y was within 0.3 mm, and the amount of deviation in the thickness direction was within 0.1 mm.

  The widths of the weld bead 72 and the heat-affected region 73 visually observed were measured. The width of the weld bead 72 was 2 mm, and the width of the heat affected zone 73 was 10 mm.

  When the location where the deviation | shift amount in the width direction Y was the largest among the welding parts 13w was specified, and the cross section of the specified location was test | inspected, the welding defect was not confirmed. Welding failure is a state in which a gap is generated without being joined. In addition, the number of pinholes having a diameter of 40 μm or more was 2 per 1 m in the longitudinal direction, which was a level that could be repaired.

  The front end and the rear end of the band member 13 were butted and welded to form an annular band 91. The surface of the band 91 was polished and passed over rollers 131 and 132 having a diameter of 2 m to carry out solution casting.

[Solution casting experiment 1]
The cellulose acylate 111 used was cellulose diacetate (DAC), and the film 116 was produced by solution casting using the solution casting equipment 110. The film 116 is used as a retardation film for a so-called LCD VA (Vertical Alignment) system. The dope 113 flowed out of the casting die 133 so that the dope 113 started to contact the band 91 on the roller 131. The wind shield 146, the roller 147, and the first slitter 118 were not used.

The tension of the band 91 was 20 ton (= 2 × 10 ⁵ N). Even if the film formation was continued, the side portion 91s did not warp on the rollers 131 and 132, and the uneven thickness of the obtained film 116 was acceptable.

[Solution casting experiment 2]
A support roller (not shown) that supports the band 91 is disposed between the roller 131 and the roller 132, and a casting die 133 is disposed so that the dope 113 starts to contact the band 91 on the support roller. The dope 113 flowed out of the casting die 133. Other conditions are the same as those in Experiment 1.

  As a result of continuing the film formation, the side portion 91s warped on the rollers 131 and 132 by about 0.1 mm. Due to the warp of the band 91, casting unevenness and a change in the clearance between the decompression chamber (not shown) and the band 91 occurred, and stepwise thickness unevenness was confirmed in the film 116.

  The third roller 28 is replaced with a taper roller 81. The tapered roller 81 has a diameter d at one end of 52 mm, a diameter at the other end of 50 mm, and a length from one end surface to the other end surface of 550 mm. Other welding methods and conditions are the same as those in Example 1.

  Over a length of 120 m, the amount of deviation in the width direction Y was within 0.3 mm, and the amount of deviation in the thickness direction was within 0.1 mm.

  The width of the weld bead 72 was 2 mm, and the width of the heat affected zone 73 was 10 mm.

  When the location where the deviation | shift amount in the width direction Y was the largest among the welding parts 13w was specified, and the cross section of the specified location was test | inspected, the welding defect was not confirmed. The number of pinholes having a diameter of 40 μm or more was 2 per 1 m in the longitudinal direction, which was a level that could be repaired.

  In the same manner as in Example 1, a band 91 was produced, and solution casting was performed.

  In the same manner as in Example 1, Experiments 1 and 2 of solution casting were performed.

  In Experiment 1, the side 91s did not warp on the rollers 131 and 132 even when film formation was continued, and the uneven thickness of the obtained film 116 was acceptable.

  In Experiment 2, as a result of continuing the film formation, the side portion 91s warped on the rollers 131 and 132 by about 0.1 mm. Due to the warp of the band 91, casting unevenness and a change in the clearance between the decompression chamber (not shown) and the band 91 occurred, and stepwise thickness unevenness was confirmed in the film 116.

  Instead of the third roller 28, a clip 85 was used. The clip 85 was run at the same speed as the central member 12.

  Over a length of 120 m, the amount of deviation in the width direction Y was within 0.3 mm, and the amount of deviation in the thickness direction was within 0.1 mm.

  The width of the weld bead 72 was 2 mm, and the width of the heat affected zone 73 was 10 mm.

  When the location where the deviation | shift amount in the width direction Y was the largest among the welding parts 13w was specified, and the cross section of the specified location was test | inspected, the welding defect was not confirmed. The number of pinholes having a diameter of 40 μm or more was 2 per 1 m in the longitudinal direction, which was a level that could be repaired.

  In the same manner as in Example 1, a band 91 was produced, and solution casting was performed.

  In the same manner as in Example 1, Experiments 1 and 2 of solution casting were performed.

  In Experiment 1, the side 91s did not warp on the rollers 131 and 132 even when film formation was continued, and the uneven thickness of the obtained film 116 was acceptable.

  In Experiment 2, as a result of continuing the film formation, the side portion 91s warped on the rollers 131 and 132 by about 0.1 mm. Due to the warp of the band 91, casting unevenness and a change in the clearance between the decompression chamber (not shown) and the band 91 occurred, and stepwise thickness unevenness was confirmed in the film 116.

  This embodiment is the same as the first embodiment except that the pressing device 62 shown in FIGS. 3 and 4 is further used. The first belt 63 and the second belt 64 are made of SUS304 and have a thickness of 1 mm and a width of 40 mm. The fifth roller 67 is arranged so that the positions of the upstream ends of the first belt 63 and the second belt 64 are 3 mm from the butting position Pc.

  Over a length of 120 m, the amount of deviation in the width direction Y was within 0.3 mm, and the amount of deviation in the thickness direction was 0 mm.

  In the same manner as in Example 1, a band 91 was produced, and solution casting was performed.

  In the same manner as in Example 1, Experiments 1 and 2 of solution casting were performed.

  In Experiment 1, the side 91s did not warp on the rollers 131 and 132 even when film formation was continued, and the uneven thickness of the obtained film 116 was acceptable.

  In Experiment 2, as a result of continuing the film formation, the side portion 91s warped on the rollers 131 and 132 by about 0.1 mm. Due to the warp of the band 91, casting unevenness and a change in the clearance between the decompression chamber (not shown) and the band 91 occurred, and stepwise thickness unevenness was confirmed in the film 116.

  Instead of the first belt 63 and the second belt 64 used in Example 4, a first belt 63 and a second belt 64 made of copper Cu were used. Moreover, the welding support roller 41 provided with the high heat conductive part 71 which consists of copper Cu was used. Other conditions are the same as those in the fourth embodiment.

  The width of the heat affected zone 73 was 4 mm, which was smaller than that in Example 1.

  In the same manner as in Example 1, a band 91 was produced, and solution casting was performed.

  In the same manner as in Example 1, Experiments 1 and 2 of solution casting were performed.

  In Experiment 1, the side 91s did not warp on the rollers 131 and 132 even when film formation was continued, and the uneven thickness of the obtained film 116 was acceptable.

  In Experiment 2, as a result of continuing the film formation, the side portion 91s warped on the rollers 131 and 132 by about 0.1 mm. Due to the warp of the band 91, casting unevenness and a change in the clearance between the decompression chamber (not shown) and the band 91 occurred, and stepwise thickness unevenness was confirmed in the film 116.

  Instead of continuous welding on the back surface, intermittent welding was performed, whereby the side member 11 and the central member 12 were temporarily joined from the back surface. The other conditions are the same as in the first embodiment.

  Over the length of 120 m, the amount of deviation in the width direction Y was within 0.1 mm.

  The width of the weld bead 72 was 2 mm, and the width of the heat affected zone 73 was 10 mm.

  When the location where the deviation | shift amount in the width direction Y was the largest among the welding parts 13w was specified, and the cross section of the specified location was test | inspected, the welding defect was not confirmed. The number of pinholes having a diameter of 40 μm or more was 2 per 1 m in the longitudinal direction, which was a level that could be repaired.

  In the same manner as in Example 1, a band 91 was produced, and solution casting was performed.

  In the same manner as in Example 1, Experiments 1 and 2 of solution casting were performed.

  In Experiment 1, the side 91s did not warp on the rollers 131 and 132 even when film formation was continued, and the uneven thickness of the obtained film 116 was acceptable.

  In Experiment 2, as a result of continuing the film formation, the side portion 91s warped on the rollers 131 and 132 by about 0.1 mm. Due to the warp of the band 91, casting unevenness and a change in the clearance between the decompression chamber (not shown) and the band 91 occurred, and stepwise thickness unevenness was confirmed in the film 116.

  While the contact position Ps was detected by the position detection means 47 and the position of the welding apparatus main body 46 was controlled, the back surface continuous welding and the front surface continuous welding were performed. The other conditions are the same as in the first embodiment.

  Over the length of 120 m, the amount of deviation in the width direction Y was within 0.1 mm.

  The width of the weld bead 72 was 2 mm, and the width of the heat affected zone 73 was 10 mm.

  When the location where the deviation | shift amount in the width direction Y was the largest among the welding parts 13w was specified, and the cross section of the specified location was test | inspected, the welding defect was not confirmed. The number of pinholes having a diameter of 40 μm or more was 2 per 1 m in the longitudinal direction, which was a level that could be repaired.

  In the same manner as in Example 1, a band 91 was produced, and solution casting was performed.

  In the same manner as in Example 1, Experiments 1 and 2 of solution casting were performed.

  In Experiment 1, the side 91s did not warp on the rollers 131 and 132 even when film formation was continued, and the uneven thickness of the obtained film 116 was acceptable.

  In Experiment 2, as a result of continuing the film formation, the side portion 91s warped on the rollers 131 and 132 by about 0.1 mm. Due to the warp of the band 91, casting unevenness and a change in the clearance between the decompression chamber (not shown) and the band 91 occurred, and stepwise thickness unevenness was confirmed in the film 116.

  The inside of the chamber 52 was cleaned, and the cleanliness at the welding position Pw was maintained at class 1000. The other conditions are the same as in the first embodiment.

  The number of pinholes having a diameter of 40 μm or more was 0.5 per 1 m in the longitudinal direction, which was a level that could be repaired.

  In the same manner as in Example 1, a band 91 was produced, and solution casting was performed.

  In the same manner as in Example 1, Experiments 1 and 2 of solution casting were performed.

  In Experiment 1, the side 91s did not warp on the rollers 131 and 132 even when film formation was continued, and the uneven thickness of the obtained film 116 was acceptable.

  In Experiment 2, as a result of continuing the film formation, the side portion 91s warped on the rollers 131 and 132 by about 0.1 mm. Due to the warp of the band 91, casting unevenness and a change in the clearance between the decompression chamber (not shown) and the band 91 occurred, and stepwise thickness unevenness was confirmed in the film 116.

  Example 1 is the same as Example 1 except that the temperature of the weld Pw is set to 150 ° C. using the heating unit 19.

  Over a length of 120 m, the amount of deviation in the width direction Y was within 0.3 mm, and the amount of deviation in the thickness direction was within 0.1 mm.

  The width of the weld bead 72 was 2 mm, and the width of the heat affected zone 73 was 10 mm.

  When the location where the deviation | shift amount in the width direction Y was the largest among the welding parts 13w was specified, and the cross section of the specified location was test | inspected, the welding defect was not confirmed. The number of pinholes having a diameter of 40 μm or more was 2 per 1 m in the longitudinal direction, which was a level that could be repaired.

  In the same manner as in Example 1, a band 91 was produced, and solution casting was performed.

  In the same manner as in Example 1, Experiments 1 and 2 of solution casting were performed.

  In Experiment 1, the side 91s did not warp on the rollers 131 and 132 even when film formation was continued, and the uneven thickness of the obtained film 116 was acceptable.

  Even in Experiment 2, the side 91s did not warp on the rollers 131 and 132 even when film formation was continued, and the unevenness of the thickness of the obtained film 116 was acceptable.

  The band 91 obtained in Example 1 was used. At the contact start position where the dope 113 starts to contact the band 91, rollers 147 are disposed both upstream and downstream of the contact start position so that the lift of the side portion 91s is suppressed to 0 mm in the vicinity of the welded portion 91w. The side portion 91s was pressed by the roller 147.

  In both Experiment 1 and Experiment 2, the side 91s did not warp on the rollers 131 and 132 even when film formation was continued, and the uneven thickness of the obtained film 116 was acceptable.

  The 1st slitter 118 was provided and the side part was excised by the center part 91c inside the welding part 91w. Other than this, the second embodiment is the same as the first embodiment.

  The amount of deviation of the optical axis in the width direction Y was 0.2 ° smaller than that in Example 1, and improved.

  Except for adjusting the position of the wind shield plate 146 and forming a film so that the welded portion 91w enters the inner side of the wind shield plate 146 when the band 91 is viewed from the direction perpendicular to the band surface. Same as 1.

  In the stripping position where the casting film 136 is stripped from the band 91, the amount of change in the angle (stripping angle) between the band 91 and the film 116 was 3 ° in the first embodiment, whereas this embodiment Then, the effect of becoming smaller was confirmed and was 1 °.

[Comparative example]
The conveyance path between the side member 11 and the central member 12 by the first roller 26 to the third roller 28 was not controlled, and the abutting position Pc was not held constant. Other conditions are the same as those in the first embodiment.

  The shift amount in the width direction Y was about 1.5 mm over a length of 120 m.

  When the location where the deviation | shift amount in the width direction Y was the largest among the welding parts 13w was specified and the cross section of the specified location was test | inspected, the welding defect was confirmed.

DESCRIPTION OF SYMBOLS 10 Band manufacturing equipment 11 Side member 12 Center member 13 Band member 17 Butting | matching part 18 Welding unit 19 Heating part 26-29 1st roller-4th roller 42 Welding device 55 Cleaning device 62 Pressing device 63,64 1st belt, 2nd Belt 71 High heat conduction part

Claims (18)

In a method for producing a band in which metal sheet materials are connected in a ring shape, as a casting support for solution casting,
While transporting a side sheet material that is a side part of the band and a central sheet material that is wider than the side sheet material and is a central part in the width direction of the band, the side sheet material A butting step of abutting so that one side edge of the center sheet material and one side edge of the central portion sheet material,
Longitudinal welding process of welding in the longitudinal direction by welding means while conveying the side sheet material and the central sheet material that have been butted,
A method for manufacturing a band, comprising: an annular welding step for welding each front end and each rear end of the welded side sheet material and the central sheet material to form an annular shape. In the longitudinal welding process,
The center sheet material and the side sheet material are supported by a peripheral surface of a support roller disposed so as to face the welding means, and welding is performed on the support roller. Band manufacturing method.   Of the peripheral surface of the support roller, in the passage region where one side edge of the side sheet material and one side edge of the center sheet material pass, the center sheet material and the side sheet material The method for manufacturing a band according to claim 2, wherein a high thermal conductivity portion made of a material having higher thermal conductivity is formed. In the matching step,
One of the central sheet material and the side sheet material is contacted and conveyed by a rotating roller arranged upstream of the welding means and rotating in the circumferential direction, and the one being contacted and conveyed is approaching the other. The method for manufacturing a band according to any one of claims 1 to 3, wherein the direction of the longitudinal direction of the rotary roller is controlled. In the matching step,
A taper roller that rotates in the circumferential direction and is formed so that the diameter gradually decreases from one end to the other end, and the one end faces the conveyance path of the central sheet material, and is arranged in the conveyance path of the side sheet material The method for manufacturing a band according to any one of claims 1 to 3, wherein the side sheet material is conveyed to the center sheet material. In the matching step,
The gripping means for displacing the central part sheet material in the width direction grips the side part sheet material and brings the side part sheet material toward the central part sheet material. The manufacturing method of the band of description. A pair of belts are arranged so as to face the support rollers so as to be aligned in the longitudinal direction of the support rollers,
By pressing the central sheet material on the support roller on one side of the pair of belts and pressing the side sheet material on the support roller on the other side, the central sheet material and the side sheet The band manufacturing method according to any one of claims 2 to 6, wherein the heights at the welding position with the material are made equal.   The band manufacturing method according to claim 7, wherein the pair of belts are formed with a high thermal conductivity portion made of a material having a higher thermal conductivity than the central sheet material and the side sheet material. . Detecting the contact position in the longitudinal direction of the support roller by detection means that is arranged upstream of the welding means and detects a contact position where the side sheet material and the central sheet material are in contact with each other,
9. The welding is performed by displacing the welding means in the width direction of the support roller based on the conveyance speed of the side sheet material and the central sheet material and the detected contact position. The manufacturing method of the band of any one of Claims. The longitudinal welding process includes
A continuous welding step of continuously welding the side sheet material and the central sheet material;
The band manufacturing method according to any one of claims 1 to 9, further comprising: an intermittent welding process in which the side sheet material and the central sheet material are intermittently welded before the continuous welding process. Method.   The cleanliness of the welding position where the side sheet material and the center sheet material which are abutted with each other is welded by the welding means is made to be a class 1000 or less in US Federal Standard FED-STD-209D. The method for manufacturing a band according to any one of claims 1 to 10.   The welded portion of the welded side sheet material and the central sheet material is heated by a heating means to remove stress in the welded portion. Band manufacturing method. Used as a casting support for solution casting, in a production facility for a band in which metal sheet materials are connected in an annular shape,
One side edge of the side sheet material that becomes the side part of the band, and one side edge of the center part sheet material that is wider than the side sheet material and becomes the center part in the width direction of the band Abutting means for abutting the side sheet material and the central sheet material that are being conveyed,
Longitudinal welding means that is provided downstream of the abutting means and welds the supplied side sheet material and the central sheet material in the longitudinal direction;
An apparatus for manufacturing a band, comprising: annular welding means for welding a front end and a rear end of a sheet material made of the side sheet material and the central sheet material welded in a longitudinal direction.   The support roller which is arranged so as to oppose the welding means and supports the central part sheet material and the side part sheet material welded by the welding means on a peripheral surface is provided. Equipment for manufacturing the described band.   Of the peripheral surface of the support roller, in the passage region where one side edge of the side sheet material and one side edge of the center sheet material pass, the center sheet material and the side sheet material The band manufacturing equipment according to claim 14, wherein a high thermal conductivity portion made of a material having a higher thermal conductivity than the band is formed. A cast film is formed by continuously casting a dope in which a polymer is dissolved in a solvent on a cast support being transported, and the cast film is peeled off from the cast support and dried. In the solution casting method as a film,
A band manufactured by the method for manufacturing a band according to any one of claims 1 to 12, is used as the casting support.
The side sheet material of the band from the one band surface side where the dope is cast by rollers rotatably provided upstream and downstream of a contact start position at which the dope starts to contact the band. A solution casting method characterized in that the side region formed from the above is pressed to maintain a height equal to that of the central region formed from the central sheet material. The tenter having holding means for holding both sides of the casting film peeled off from the casting support and drying means for drying the casting film is dried while holding the casting film,
The solution casting method according to claim 16, wherein, of the casting film peeled off from the casting support, a side part peeled off from the side region is excised before being guided to the tenter. . Arranging a pair of wind-shielding members that block the flow of gas so as to face each of the one side region and the other side region,
The solution casting method according to claim 16 or 17, wherein the casting film on the casting support is dried by supplying the gas between the pair of wind shielding members.

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