JP2011183724A - Tentering machine, method for eliminating foreign substance in tentering machine and solution film forming equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stabilize film conveyance by eliminating foreign substances which hamper film conveyance. <P>SOLUTION: A film in a pin tenter is conveyed with both side ends held by a pin 72 and a pin plat 73. Pin 72 and pin plate 73 are sent to a jet air cleaning area 83 when they are released from film holding. The pin 72 and the pin plate 73 are covered with a chamber 202 in the jet air cleaning area 83. A jet air is blasted to the pin 72 and the pin plate 73 in the chamber 202. Foreign substances, including liquefied or solidified film additives and blanking dregs generated when the pin 72 is inserted in the film, are eliminated from the pin 72 and the pin plate 73 by the blasting of jet air. The foreign substances are ejected out of the chamber 202 through a suction nozzle. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a tenter device that dries a film while stretching both sides of the film at a constant width-enhancing rate, and a foreign matter removing method in the tenter device. The present invention also relates to a solution casting apparatus equipped with the tenter device.

  Polymer films have excellent light transmittance and flexibility, and can be made light and thin, and thus are widely used as optical functional films. Among these, the cellulose ester film using cellulose acylate or the like has toughness and low birefringence in addition to the above-described properties. This cellulose ester film is used as a protective film and an optical compensation film for a polarizing plate, which is a constituent member of a liquid crystal display (LCD) whose market is expanding in recent years, including a photographic photosensitive film.

  One method for producing a polymer film is a solution casting method. According to this solution casting method, first, a dope containing a polymer and a solvent is cast from a casting die onto a support to form a casting film. Next, after the cast film has self-supporting properties, the cast film is peeled off from the support as a wet film. And the wet film is conveyed in the state which hold | maintained the both ends (henceforth "ear part") of the wet film with the tenter. Further, in the tenter, the ear portion is stretched in the width direction with respect to the wet film being conveyed, and drying is performed by blowing dry air. Thereby, a film is obtained. And after cutting | disconnecting the ear | edge part of a film, it dries further with a drying apparatus. The film that has passed through the drying device is wound up by a winding device.

  Drying of the wet film in the tenter is performed by carrying both ends of the film by carrying means such as clips and pins, and blowing dry air on the running film. On the other hand, since the supporting means is fixed to an endless moving body such as a chain and circulates, if the film is again supported by the supporting means that has been exposed to high temperature drying air near the tenter outlet and becomes hot, boiling of the solvent in the film will occur. May cause foaming, leading to film cutting. In addition, in the solution casting method in which self-supporting property is provided by cooling gelation, the film is supported by the pin plate, but when the temperature of the pin is high, the resin that covers the tip of the pin when the pin enters the film is solidified. It peels off to form a cap-like powder, which causes foreign matter failure and scratches. In order to prevent this, the supporting means is cooled by passing through a cooling duct before supporting both side ends of the film (see, for example, Patent Document 1).

JP-A-9-85846

  However, the provision of cooling ducts creates new problems. In the tenter, the solvent gas evaporated from the wet film is filled. Under a high temperature atmosphere in the tenter, the plasticizer and UV agent in the wet film are evaporated together with the solvent, and these are also mixed in the solvent gas. Such solvent gas is entrained in the cooling duct as the clip or pin plate moves. The solvent gas that has entered the cooling duct is liquefied or solidified by cooling the cooling duct, and adheres to the pins and the pin plate as foreign matter. This foreign material contains a large amount of additives such as plasticizers and UV agents added to the dope. When the amount of accumulated foreign matter increases, a large burden is placed on the pin plate. Furthermore, if foreign matter accumulates on the conveying guide roller used for conveying the pin plate or the bearing used therefor, the film cannot be conveyed stably.

  For the above problems, measures such as introduction of a plasticizer or UV agent that hardly evaporate, lowering the drying temperature of the tenter, and increasing the drying time of the tenter can be considered. However, taking these measures is not preferable because it causes new problems such as a change in the quality of the film after manufacture and an extra cost. In addition, it is possible to remove foreign matter adhering to the pin plate using a brush or the like. However, as the foreign matter is repeatedly removed, the brush becomes clogged, or once removed foreign matter adheres to the pin plate again. There are problems such as. There is also a problem that there are parts that cannot be removed with a brush.

  In the tenter, the solvent is recovered from the solvent gas in the tenter by condensation recovery or adsorption recovery, and the gas from which the solvent has been removed is sent back into the tenter. Etc. are collected. However, even if this method is used, the amount of foreign matter adhering to the pin plate or the like cannot be completely eliminated.

  Although it is conceivable to clean the pin plate using a cleaning solvent, the cleaning effect is weak and the cleaning solvent dissolves the oil component as a lubricant for the conveying guide roller and the bearing. There is a problem. Furthermore, when the cleaning solvent evaporates in the tenter, there is a problem that the cleaning solvent must be recovered. Therefore, until now, the film production line was periodically stopped and the pin plate and the like were washed off-line.

  Further, in the pin tenter, in addition to the foreign matter generated in the cooling duct as described above, punched debris generated when the pin is inserted into the film, burrs remaining around the pin when the pin is extracted from the film, etc. Foreign matter may also adhere and accumulate on the pin plate. Similar to the foreign matter generated in the cooling duct as described above, such foreign matter not only prevents stable conveyance of the film, but also contributes to in-process contamination in the pin tenter 13 and When mixed in the film, the film quality may be affected.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a tenter device that removes foreign matters that obstruct film conveyance and stabilizes film conveyance, a foreign matter removal method in the tenter device, and a solution casting apparatus.

  In order to achieve the above object, a tenter device according to the present invention includes a supporting member that supports both side ends of a film being conveyed, a supporting section in which the supporting member supports the film, and the supporting member is the film. A circulatory moving part that circulates and moves the carrier member between the release section for releasing the carrier and the film in the carrier section to gradually shift the carrier member in a direction in which the film widens. A stretching / drying section that stretches at a constant widening ratio and that is dried by blowing dry air, a chamber that covers the support member in the release section, and a jet that supports the support member that sequentially passes through the chamber. A jet wind blowing unit that removes foreign matter adhering to the support member by blowing air; and a different type of discharging the foreign matter out of the chamber. Characterized in that it comprises a discharge portion.

  The foreign matter discharge section includes an upstream suction chamber provided upstream of the jet wind blowing section and a downstream suction provided downstream of the jet wind blowing section with respect to the moving direction of the support member. It is preferable that the foreign matter is sucked into the chamber, and the sucked foreign matter is discharged out of the chamber together with the jet wind through a discharge nozzle attached to the upstream suction chamber and the downstream suction chamber. The upstream suction chamber and the downstream suction chamber are preferably in a negative pressure state.

  The jet wind blown to the support member in the chamber is collected, and the collected jet wind is returned to the chamber, so that the jet wind circulation section for circulating the jet wind and a part of the collected jet wind are released. It is preferable to include a jet wind escape section and a control section that controls the temperature of the jet wind blown to the support member by adjusting the amount of jet wind that is released by the jet wind escape section.

  In the present invention, a dope containing a polymer, a solvent, and an additive is cast on a support to form a cast film, the cast film is peeled off from the support as a wet film, and the wet film is separated by a tenter device. In the solution casting apparatus for producing a film by stretching the film in the width direction and drying it by blowing dry air, the tenter device includes a supporting member that supports both side ends of the wet film being transported, and the supporting member. Between the carrying section for carrying the wet film and the release section for releasing the carrying of the wet film by the carrying member, and the circulation moving part for circulating the carrying member, and the carrying member in the release section The additive is liquefied or solidified by blowing jet air against the chamber covering the chamber and the support member that sequentially passes through the chamber. A jet wind blowing unit that removes foreign matter including debris and burrs generated when the carrying of the carrying member is started or released from the carrying member, and a foreign matter discharge unit that discharges the foreign matter together with the jet wind to the outside of the chamber. It is characterized by providing.

  The tenter device is provided with a separation unit that separates the foreign matter and the jet wind, and is gradually lowered from the foreign matter discharge unit toward the separation unit, and removes the foreign matter from the foreign matter discharge unit to the separation unit. It is preferable to provide a downwardly inclined pipe that is fed to

  The tenter device collects the jet wind blown to the support member in the chamber and returns the recovered jet wind to the chamber, thereby circulating the jet wind, and the recovered jet wind A jet wind escaping part for escaping a part of the jet air, and a control part for controlling the temperature of the jet wind blown to the support member by adjusting the air volume of the jet wind escaped by the jet wind escaping part. It is preferable to control the temperature of the jet air so that the temperature exceeds the melting point of the additive and is less than the heat resistance temperature of various devices in the tenter device. The temperature of the jet wind is preferably 49 ° C. or higher and controlled to 120 ° C. or lower, which is the heat resistant temperature of various devices in the tenter device. The tenter device is preferably a pin tenter including a pin and a pin plate in which a large number of pins are planted as the carrying member.

  In the tenter device according to the present invention, the foreign material removing method includes the carrier member between a section in which both end portions of the film being conveyed are supported by the support member and a release section in which the support of the film is released The film is circulated and stretched at a constant widening ratio by gradually shifting the support member in the direction in which the film widens with respect to the film in the support section, and dried by blowing dry air. In the chamber covering the carrier member in the release section, the foreign matter attached to the carrier member is removed by blowing jet air against the carrier member that sequentially passes through the chamber, and the foreign matter is moved out of the chamber. It is characterized by discharging.

  According to the present invention, it is possible to remove foreign substances that obstruct film conveyance, and to stabilize film conveyance.

It is the schematic which shows a solution casting apparatus. It is a top view which shows the pin tenter of this invention. It is a front view which shows the pin tenter of this invention. It is sectional drawing of a rail, a rail cover, and a pin carrier. It is sectional drawing of a rail, a rail cover, and a pin carrier which shows the state which the tooth | gear of the sprocket and the biting groove | channel of the pin carrier meshed | engaged. It is sectional drawing which shows the rail in a gas purge area, a rail cover, and a pin carrier. It is sectional drawing which shows the rail in a steam washing | cleaning area, a rail cover, and a pin carrier. It is sectional drawing which shows the rail in a jet wind washing | cleaning area, a rail cover, a pin carrier, a pin and the chamber for pin plate washing | cleaning, supply piping for circulating jet wind, and piping for suction. It is sectional drawing which shows the nozzle for jet wind spraying provided in the chamber, the discharge nozzle for discharging a foreign material and jet wind, etc. It is sectional drawing which shows the rail in a 1st cooling area, a rail cover, and a pin carrier.

  A first embodiment of the present invention will be described. As shown in FIG. 1, the solution casting apparatus 10 includes a casting chamber 11, a transition part 12, a pin tenter 13, a clip tenter 14, an ear clip device 15, a drying device 16, a cooling device 17, a winding device. The take-up device 18.

  In the casting chamber 11, a feed block 21 into which the dope from the dope production facility 20 is fed, a casting drum 22 as a support, a casting die 23 for casting the dope onto the casting drum 22, and casting. A stripping roller 26 for stripping the casting film 24 on the drum 22 as a wet film 25, a condenser 27 (condenser) for condensing and liquefying the solvent gas evaporated from the casting film 24 and the wet film 25, and a liquefied solvent. A recovery device 28 for recovery is provided. Further, a heat transfer medium supply device (not shown) is connected to the casting drum 22, and the surface temperature of the casting drum 22 is set to a desired value by supplying the heat transfer medium into the heat transfer medium supply device. The temperature is adjusted. Further, a temperature adjusting device 30 for adjusting the internal temperature is attached to the casting chamber 11.

  A dope channel is formed inside the feed block 21. A decompression chamber 32 is attached to the casting die 23, and the decompression chamber 32 is used for a dope flow (hereinafter referred to as “bead”) from the discharge port of the casting die 23 to the casting drum 22. The back is decompressed to stabilize the bead contact with the casting drum 22. A jacket (not shown) is attached to the decompression chamber 32, and the decompression chamber 32 is adjusted to a desired temperature.

  A number of rollers 35 are installed in the crossover section 12. These rollers 35 convey the wet film 25 peeled off from the casting drum 22 to the pin tenter 13. Hereinafter, the transport direction of the wet film 25 is referred to as the A direction. A blower 36 is provided above the conveyance path of the wet film 25, and the blower 36 blows dry air on the wet film 25 to promote drying of the wet film 25.

  The pin tenter 13 is inserted into and held by a pin at the ear portion of the wet film 25, and conveys the wet film 25 while holding the ear portion. In the pin tenter 13, the width of the wet film 25 is expanded at a constant widening ratio by extending the ear portion in the width direction. Further, drying air is sent to the wet film 25 from the drying ducts 52 and 53 (see FIG. 3), and is heated to a desired temperature, thereby promoting drying. The drying air circulation device 60 adsorbs and recovers the solvent and plasticizer from the drying air sent from the drying ducts 52 and 53, and returns the dried air after the adsorption recovery to the drying ducts 52 and 53.

  The clip tenter 14 is provided downstream of the pin tenter 13, grips and conveys the ear portion of the wet film 25 coming out of the pin tenter 13 and performs drying. In the clip tenter 14 as well, the wet film 25 is dried by blowing the dry wind while extending the ear portion in the width direction. Thereby, the film 37 is obtained. Note that the clip tenter is provided as necessary and may be omitted. In this case, the film 37 exiting the pin tenter 13 is sent to the drying device 16. The ear clip device 15 cuts the ear portion of the film 37 that has come out of the clip tenter 14. Further, a crusher 66 is connected to the ear clip device 15, and the crusher 66 crushes the ear portion of the film 37 into chips. Then, the film 37 from which the ears have been cut is sent to the drying device 16.

  A large number of rollers 67 are provided inside the drying device 16, and the film 37 is dried while being conveyed by the rollers 67. The solvent gas generated from the film 37 in the drying device 16 is adsorbed and recovered by an adsorption recovery device 69 provided outside the drying device 16. The gas from which the solvent has been removed by the adsorption recovery is returned to the drying device 16 again. The film 37 exiting the drying device 16 is sent to the cooling device 17 where it is cooled to approximately room temperature. The ear clip device may also be provided at the outlet of the pin tenter 13 so that the ear portion is cut and then sent to the clip tenter.

  The winding device 18 includes a winding core 70, and the film 37 exiting the cooling device 17 is wound around the winding core 70 in a roll shape. The winding device 18 includes a press roller 71. The press roller 71 winds the film 37 while adjusting the winding pressure.

  As shown in FIGS. 2 and 3, the pin tenter 13 carries the wet film 25 in the A direction in a state in which both end portions (ear portions) 25a of the wet film 25 are carried, and the width direction (hereinafter referred to as “ In the “B direction”) at a predetermined stretching rate. The pin tenter 13 includes a brush roller 40 for inserting a pin, a dust removing device 42, a rail 44, sprockets 46 to 48, drying ducts 52 and 53, a rail cover (duct) 54, and a pin carrier 58. .

  The brush roller 40 is provided on the inlet 13a side of the pin tenter 13, and the pin 72 (see FIG. 4) is inserted into the ear portion 25a of the wet film 25 that has entered the pin tenter 13 to its root portion. The dust removing device 42 is provided on the outlet 13b side of the pin tenter 13 and removes dust and the like on the ear portion 25a by suction.

  The rails 44 are installed on both sides of the transport path of the wet film 25. The rail 44 has its width and widening pattern determined according to the stretch ratio of the wet film 25, and the stretched state of the rail 44 is shown exaggerated. Moreover, the widening pattern is also an example, and various widening patterns may be employed in consideration of the optical characteristics of the film. The rail 44 is composed of a pair of rails 44a and 44b arranged in the vertical direction.

  The sprockets 46 and 47 are provided on the inlet 13 a side of the pin tenter 13, and the sprocket 48 is provided on the outlet 13 b side of the pin tenter 13. When the sprocket 48 is rotated by a rotational drive of a motor or the like, the pin carrier 58 for carrying the pin 72 and the pin plate in which many pins 72 are planted (see FIG. 4) travels along the rail 44. As the pin carrier 58 travels, the sprockets 46 and 47 rotate.

  The dry duct 52 is installed above the transport path of the wet film 25, and the dry duct 53 is installed below the transport path of the wet film 25. The drying duct 52 blows dry air on the upper surface of the wet film 25. Further, the drying duct 53 blows dry air on the lower surface of the wet film 25. The temperature of the drying air in the drying ducts 52 and 53 is set to a predetermined temperature in the range of 40 ° C. or more and 200 ° C. or less. Thereby, drying of the wet film 25 is promoted, and the solvent gas evaporates from the wet film 25.

  As shown in FIG. 4, the rail cover 54 covers a part of the rails 44 a and 44 b and the pin carrier 58. A rail 44a is attached to the upper surface inside the rail cover 54, and a rail 44b is attached to the lower surface thereof. The pin carrier 58 is disposed between the rail 44a and the rail 44b. In addition, a slit 54 a is formed in the rail cover 54 along the traveling direction of the pin carrier 58. The slit 54a is covered with a wind shielding member 75, which will be described later, so that inert gas and cooling air sent into the rail cover 54 do not escape. As shown in FIG. 5, the rail cover 54 near the position where the sprocket 46 is installed has a slit 54b for the sprocket 46 to enter. The same applies to the rail cover 54 in the vicinity of the position where the sprocket 47 is installed, and a description thereof will be omitted.

  As shown in FIG. 4, the pin carrier 58 includes a pin 72, a pin plate 73, a carrier body 74, a wind shielding member 75, and guide rollers 76 to 79. The pin 72 and the pin plate 73 constitute a support member. A large number of pins 72 are planted on the pin plate 73 at predetermined intervals. The pin plate 73 is fixed to the wind shield 75 a of the wind shield member 75. A protrusion 74 a for supporting the wind shielding member 75 is formed on the side surface of the carrier body 74. A wind shield member 75 is fixed to the protrusion 74a. A meshing groove 74 b that meshes with the teeth of the sprockets 46, 47, 48 is formed at the center of the lower surface of the carrier body 74.

  The wind shield member 75 is fixed to the protrusion 74 a of the carrier body 74 through the slit 54 a of the rail cover 54. The wind shield 75 includes a wind shield 75a extending in the vertical and horizontal directions so as to cover the slit 54a. The wind shield 75a covers the slit 54a of the rail cover 54. The wind shield 75 a prevents dry air containing solvent gas evaporated from the wet film 25 from entering the rail cover 54. Further, the wind shield 75a prevents the steam from entering the rail cover 54 when the pins 72 and the pin plate 73 are subjected to steam cleaning in a steam cleaning area 82 (see FIG. 7) described later.

  The guide roller 76 and the guide roller 77 are provided on the upper surface of the carrier body 74 so as to be separated from each other by the width of the rail 44a. Similarly, the guide roller 78 and the guide roller 79 are provided on the lower surface of the carrier body 74 so as to be separated by the width of the rail 44b. These guide rollers 76 to 79 sandwich the rails 44a and 44b, and guide the carrier body 74 when the carrier body 74 moves along the rails 44a and 44b.

  A connection bracket for connecting the carrier bodies 74 to each other is provided at the front end portion and the rear end portion in the traveling direction of each carrier body 74, and a connection pin is attached to the connection bracket in the horizontal direction. Therefore, since each carrier main body 74 is connected via the connecting pin, it can run and move in the vertical plane as shown in FIG. Instead of connecting the block-shaped carrier bodies to each other with connecting pins to form the pin carrier, the pin carrier may be formed using a chain.

  As shown in FIG. 3, the pin tenter 13 includes a gas purge area 81, a steam cleaning area 82, a jet wind cleaning area 83, a first cooling area along the traveling direction of the pin carrier 58 from which the wet film 25 is released. 84, a second cooling area 86 is provided. Most of the foreign matters removed by the cleaning in the steam cleaning area 82 and the jet wind cleaning area 83 are components contained in the solvent gas evaporated from the wet film 25, particularly TPP (triphenyl phosphate), BDP (biphenyl diphenyl phosphate). ), Plasticizers such as polyesters, and dope additives such as UV agents such as benzotriazole materials are liquefied or solidified, as well as punching residue generated when pins are inserted into the film, and pins from the film It also includes burrs that remain around the pins when extracted. Further, the foreign matters include those in which the optical property adjusting agent is liquefied or solidified. By removing such foreign matters, there is no pin carrier 58 that obstructs the conveyance of the wet film, and in-process contamination in the pin tenter 13 can be prevented, and foreign matters can be mixed into the wet film 25. Can be prevented.

  As shown in FIG. 6, an air supply nozzle 90 and an intake exhaust pipe 91 are attached to the rail cover 54 located in the gas purge area 81, and the outlet hole of the nozzle 90 and the intake hole of the exhaust pipe 91 are , Respectively, are directed to the inside of the rail cover 54. In the gas purge area 81, a nitrogen gas supply unit 94, a suction device 95, and a filter 96 are installed. The nitrogen gas supply unit 94 is connected to the nozzle 90, and the suction device 95 is connected to the discharge pipe 91. The suction device 95 is connected to the nitrogen gas supply unit 94 via the filter 96.

  When performing the gas purge, nitrogen gas is supplied from the nitrogen gas supply unit 94 to the nozzle 90. The nitrogen gas is supplied into the rail cover 54 through the blowout hole of the nozzle 90. By blowing out nitrogen gas from the nozzle 90, the pressure inside the rail cover 54 increases, and foreign substances attached to the carrier body 74, the guide rollers 76 to 79, and the rails 44a and 44b are removed. The suction device 95 sucks in gas from the pressurized rail cover 54 through the suction hole of the discharge pipe 91 and sucks foreign matter accumulated in the rail cover 54. The filter 96 removes foreign substances from the gas sucked by the suction device 95. The nitrogen gas from which the foreign matter has been removed is sent to the nitrogen gas supply unit 94.

  Among the gas purge areas 81, the area where the holding of the ear portion 25a of the wet film 25 is released is an area where the concentration of the solvent gas is particularly high in the pin tenter 13 as well. Accordingly, by increasing the pressure inside the rail cover 54 by supplying nitrogen gas, the solvent gas can be prevented from entering the rail cover 54. Even if solvent gas enters the rail cover 54 and the solvent gas is liquefied or solidified and adheres to the guide rollers 76 to 79 as foreign matter, such foreign matter is removed by blowing nitrogen gas. . Furthermore, since the removed foreign matter is discharged out of the rail cover 54 by the suction device 95, there is no object that obstructs the travel of the pin carrier 58 in the rail cover 54. As a result, the pin carrier 58 can stably travel along the rail 44.

  The gas purge may be performed not only in the transport area of the wet film 25 but also in the entire area where the pin carrier 58 travels. Further, although the discharge pipe 91 is provided on the opposite side of the rail cover 54 at a position corresponding to the nozzle 90, the discharge pipe 91 may be provided away from the nozzle 90 in the traveling direction of the pin carrier 58. In this case, by setting the discharge position away from the position of the nozzle 90, it is possible to efficiently set the pressure in the rail cover 54 higher than that of the tenter chamber. A plurality of nozzles 90 and discharge pipes 91 may be provided in the gas purge area 81 at an appropriate pitch in the traveling direction of the pin carrier 58.

  As shown in FIG. 7, nozzles 120 a to 120 c for spraying steam are installed in the steam cleaning area 82. The outlet hole of the nozzle 120 a is directed in the direction of the pin 72 and the pin plate 73. The blowout holes of the nozzles 120b and 120c are directed toward the rails 44a and 44b, the carrier body 74, and the guide rollers 76 to 79. Further, a steam supply unit 122 is installed in the steam cleaning area 82, and the steam supply unit 122 is connected to the nozzles 120a to 120c.

  When performing steam cleaning, steam is supplied from the steam supply unit 122 to the nozzles 120a to 120c. This steam is sprayed to the pin 72 and the pin plate 73 from the blowout hole of the nozzle 120a. Further, the steam is blown to the rails 44a and 44b, the carrier body 74, and the guide rollers 76 to 79 from the blowing holes of the nozzles 120b and 120c. By the spraying of the steam, the foreign matters adhering to the pins 72, the pin plate 73, the rails 44a and 44b, the carrier main body 74, and the guide rollers 76 to 79 are removed. In addition, although the foreign material was removed by spraying steam, it is not limited to this, and cleaning may be performed using a vapor containing a liquid having a high effect of removing the foreign material.

  As shown in FIG. 8, jet air is blown from the nozzles 203 and 204 disposed in the chamber 202 to the pin 72 and the pin plate 73 in the jet air cleaning area 83. By blowing jet air in the chamber 202, foreign matters such as punch debris and burrs are removed from the pins 72 and the pin plate 73. Further, the foreign matter accumulated in the chamber 202 is discharged out of the chamber 202 by the exhaust nozzle 240 (see FIG. 9).

  The jet wind is supplied from a blower 205 outside the casing 200 via a supply pipe 206. The supply pipe 206 connects between the blower 205 and the chamber 202. In the middle of the supply pipe 206, an escape wind pipe 208 for attaching a part of the jet wind from the supply pipe 206 and releasing it into the casing 200 is attached. At a branch point between the supply pipe 206 and the escape wind pipe 208, a three-way valve 209 that adjusts the amount of jet air that escapes to the escape wind pipe 208 is attached.

  The foreign matter generated in the chamber 202 is sent to the centrifuge 212 together with the jet wind through the suction pipe 210. The centrifuge 212 is provided at a position lower than the chamber 202, and the suction pipe 210 connecting them is inclined so as to gradually become lower from the chamber 202 toward the centrifuge 212. As described above, the foreign matters flowing in the suction pipe 210 include not only solid materials such as punched debris but also liquefied materials in which TPP or the like has been liquefied. Therefore, by setting the suction pipe 210 to a downward slope, the liquefied or solidified foreign matter can be reliably sent to the centrifuge 212 without clogging in the middle of the suction pipe 210.

  The centrifuge 212 separates foreign matter and jet air sent from the suction pipe 210. The centrifuge 212 is of a cyclone type, and feeds foreign matter and jet air from the suction pipe 210 along the inner peripheral surface of the cylindrical main body 214. Since the foreign matter is heavier than the jet wind, each time it turns in the cylindrical main body 214, it gradually falls in a spiral shape by its own weight. Thereby, the foreign substance and the jet wind are separated. The fallen foreign matter is sent to the collection unit 216 via a hopper 215 attached to the lower part of the cylindrical main body 214. On the other hand, the jet wind separated from the foreign matter is sent to the blower 205 via the pipe 218. Of the foreign matter recovered by the recovery unit 216, the TPP can be reused by filtering.

  The chamber 202 is provided with a temperature sensor 219 for measuring the internal temperature. The controller 220 controls the opening degree of the three-way valve 209 based on the temperature in the chamber 202 measured by the temperature sensor 219. By controlling the opening degree, by controlling the amount of jet air sent to the escape air pipe 208, the temperature of the jet air coming out of the nozzles 203 and 204 in the chamber 202 can be adjusted. Accordingly, not only the temperature of the jet wind but also the temperature in the chamber 202 can be adjusted only by escaping a part of the jet wind to the wind pipe 208, so that there is an additional cost such as installation of a heater or a cooling cooler. Does not need to take. Here, when controlling by the controller 220, the temperature of the jet wind is adjusted so that the temperature exceeds the melting point of the TPP and is lower than the heat resistance temperature of the casing 200, the nozzles 203, 204, the chamber 202, and other devices. It is preferable. For example, the melting point of TPP is 49 ° C., and the heat-resistant temperature of the device is 120 ° C.

  As shown in FIG. 9, the chamber 202 has a jet wind blowing unit 230 that blows jet wind against the pins 72 and the pin plate 73, and an upstream side of the jet wind blowing unit 230 with respect to the moving direction P of the pins and the pin plate. An upstream side intake chamber 231 provided on the side and a downstream side intake chamber 232 provided on the downstream side of the jet wind blowing unit 230 are provided. The jet wind blowing unit 230 is provided on the ducts 235 and 236 into which the jet wind from the blower 205 is sent, the lower surfaces of the ducts 235 and 236, and the upper surface of the duct. A plurality of nozzles 203a to 203e and 204a to 204e sprayed toward the nozzle 73 are provided.

  The plurality of nozzles 203 a to 203 e and 204 a to 204 e are provided at regular intervals along the moving direction P of the pin 72 and the pin plate 73. The nozzles 203 a and 204 a closest to the upstream side intake chamber 231 are provided so that the jet wind blows out substantially along the moving direction P of the pin 72 and the pin plate 73. On the other hand, the other nozzles 203b to 203e, 204b to 204e are provided so that the jet wind blows in the direction Q substantially opposite to the moving direction P of the pin 72 and the pin plate 73. In addition, it is preferable that the wind speed of the jet wind sprayed from the nozzles 203a to 203e and 204a to 204e is 10 m / min or more.

  In this way, the jet wind was blown along the moving direction P by blowing the jet wind from the nozzles 203b to 203e, 204b to 204e in the direction Q almost opposite to the moving direction P of the pin 72 and the pin plate 73. The impact force when the pin 72 and the pin plate 73 and the jet wind collide with each other is larger than that. Thereby, the foreign material adhering to the pin 72 and the pin plate 73 can be easily removed. Further, even if jet air is blown in the Q direction from the downstream side toward the upstream side in this way, the jet air in the P direction which is the counter wind with respect to the jet air in the Q direction is used as the most upstream nozzle 203a. 204a, the momentum of the jet wind in the Q direction is weakened. Therefore, there is no possibility that the jet wind and the foreign matter contained in the jet wind will go out of the chamber 202 beyond the upstream side intake chamber 231.

  An exhaust nozzle 240 is attached to the upstream intake chamber 231. By exhausting the gas in the upstream intake chamber 231 through the exhaust nozzle 240, the upstream intake chamber 231 is in a negative pressure state. An exhaust nozzle 242 similar to the upstream intake chamber 231 is also attached to the downstream intake chamber 232, and the downstream intake chamber 232 is in a negative pressure state by the exhaust nozzle 242. As described above, since the upstream side intake chamber 231 and the downstream side intake chamber 232 are in a negative pressure state, the foreign matter removed from the pin 72 and the pin plate 73 by the jet wind blowing unit 230 is removed from the upstream side intake chamber 231 or the downstream side. The air is sucked into the side intake chamber 232. The foreign matter sucked into the upstream side intake chamber 231 or the downstream side intake chamber 232 is sent to the suction pipe 210 via the exhaust nozzles 240 and 242.

  As shown in FIG. 10, in the first cooling area 84, the pins 72 and the pin plate 73 are covered with a pin cover 130. A supply hole 130 a is formed on the side surface of the pin cover 130. An air supply nozzle 132 is attached to the rail cover 54 located in the first cooling area 84. The blowout hole of the nozzle 132 is directed to the inside of the rail cover 54. A cooling air supply unit 134 is installed in the first cooling area 84, and the cooling air supply unit 134 is connected to the supply hole 130a.

  In the first cooling area 84, the cooling air is supplied from the cooling air supply unit 134 so that the temperatures of the inside of the rail cover 54 and the entire inside of the pin cover 130 in the first cooling area 84 are substantially uniform. The temperature of the cooling air is, for example, a predetermined temperature of −30 ° C. or higher and + 30 ° C. or lower. Thereby, the temperature of the inside of the rail cover 54 and the whole inside of the pin cover 130 becomes below the melting point of TPP, that is, below 50 ° C. Accordingly, when TPP evaporated together with the solvent from the wet film 25 enters the first cooling area 84 with the movement of the pin carrier 58 or the pin plate 73, the TPP or the like is moved to the pin 72, the pin carrier 58, or the like. It will be deposited.

  In the second cooling area 86, only the pins 72 and the pin plate 73 are cooled by cooling air. Since the configuration of the second cooling area 86 is the same as that of the first cooling area 84 except that no pin cover is installed, the description thereof is omitted. In the second cooling area 86, the surface temperature of the pin 72 and the pin plate 73 becomes 35 ° C. or more and 50 ° C. or less by performing cooling subsequent to the first cooling area 84. By setting the temperature of the pin 72 within the above range, the pin 72 can easily pass through the ear portion 25a.

  In this embodiment, the wet film is transported without being inverted from the start of holding the ear of the wet film until it is released. However, the present invention is not limited to this, and the wet film is transported while being inverted several times. It is good also as a multistage conveyance system.

  In the present embodiment, the present invention is applied to the pin tenter in the present embodiment. However, the present invention is not limited to this, and the present invention can also be applied to a clip tenter. Moreover, although the pin tenter of the present invention was introduced into the solution casting equipment, the present invention is not limited to this, and the present invention may be implemented in a web manufacturing equipment for producing webs other than films.

  The width of the film 37 manufactured in the present embodiment is preferably 1400 mm or more and 2500 mm or less. In addition, even if it is a case where the width | variety of the film 37 exceeds 2500 mm, the effect of this invention can be acquired. In addition, the thickness of the film 37 manufactured in the above embodiment is preferably 20 μm or more and 100 μm or less, more preferably 20 μm or more and 80 μm or less, and most preferably 30 μm or more and 70 μm or less.

  In the above embodiment, the case where a single-layer film is manufactured using one kind of dope has been described. However, the present invention is also effective when a cast film having a multilayer structure is formed. In this case, a known method such as casting a desired number of dopes simultaneously or sequentially may be used, and there is no particular limitation. Also, from the structure of casting die, decompression chamber, support, etc., co-casting, peeling method, stretching, drying conditions of each process, handling method, curling, winding method after flatness correction, solvent recovery method, film The collection method is described in detail in paragraphs [0617] to [0889] of JP-A-2005-104148, and the inventions according to these descriptions can also be applied to the present invention. The performance of the completed film, the degree of curling, the thickness, and the measurement methods thereof are described in paragraphs [1073] to [1087] of JP-A-2005-104148. The invention can also be applied to the present invention.

  It is preferable to perform surface treatment on at least one surface of the completed film because the degree of adhesion with an optical member such as a polarizing plate can be increased. Examples of the surface treatment include vacuum glow discharge treatment, atmospheric pressure plasma discharge treatment, ultraviolet irradiation treatment, corona discharge treatment, flame treatment, acid treatment, alkali treatment, etc., and at least one of these treatments is performed. Is preferred.

  When the completed film is used as a base and a desired functional layer is provided on both sides or one side, it can be used as various functional films. Examples of the functional layer include an antistatic layer, a cured resin layer, an antireflection layer, an easy adhesion layer, an antiglare layer, and an optical compensation layer. For example, when an antireflection layer is provided, an antireflection film capable of preventing light reflection and providing high image quality can be obtained. The functional layer and the forming method are described in detail in paragraphs [0890] to [1072] of JP-A-2005-104148, and the inventions related to these descriptions can also be applied to the present invention. it can. Regarding specific uses of the polymer film, for example, TN type, STN type, VA type, OCB type, reflective type and the like described in paragraphs [1088] to [1265] of JP-A-2005-104148 For use in liquid crystal display devices.

  Next, the raw material of dope manufactured with the dope manufacturing equipment 20 is shown below.

  It is preferable to use cellulose ester as a dope raw material because a highly transparent film can be obtained. Examples of the cellulose ester include lower fatty acid esters of cellulose such as cellulose triacetate, cellulose acetate propionate, and cellulose acylate butyrate. Especially, it is preferable to use a cellulose acylate from the height of transparency, and it is preferable to use a triacetyl cellulose (TAC). The dope used in the above embodiment includes triacetyl cellulose (TAC) as a polymer. Thus, when using TAC, it is preferable that 90 mass% or more of TAC is a particle | grain of 0.1-4 mm.

As said cellulose acylate, in order to obtain a film with higher transparency, it is preferable that the substitution degree of the acyl group to the hydroxyl group of cellulose satisfies all of the following formulas (a) to (c). A and B in the following formula represent the substitution degree of the acyl group with respect to the hydrogen atom in the hydroxyl group of cellulose. Specifically, A is the substitution degree of the acetyl group, and B has 3 to 22 carbon atoms. The degree of substitution of the acyl group.
(A) 2.5 ≦ A + B ≦ 3.0
(B) 0 ≦ A ≦ 3.0
(C) 0 ≦ B ≦ 2.9

  Glucose units having β-1,4 bonds constituting cellulose have free hydroxyl groups at the 2nd, 3rd and 6th positions. Cellulose acylate is a polymer obtained by esterifying some or all of these hydroxyl groups with an acyl group having 2 or more carbon atoms. The degree of acyl substitution means the ratio of the esterification of the hydroxyl group of cellulose for each of the 2-position, 3-position and 6-position. The degree of substitution is 1 in the case of 100% esterification.

  The total degree of acylation substitution, that is, the value of DS2 + DS3 + DS6 is preferably 2.00 to 3.00, more preferably 2.22 to 2.90, and particularly preferably 2.40 to 2.88. Further, the value of DS6 / (DS2 + DS3 + DS6) is preferably 0.28 or more, more preferably 0.30 or more, and particularly preferably 0.31 to 0.34. Here, DS2 is a ratio in which the hydrogen of the hydroxyl group at the 2-position in the glucose unit is substituted with an acyl group, and DS3 is a ratio in which the hydrogen of the hydroxyl group at the 3-position in the glucose unit is substituted with an acyl group. DS6 is the ratio in which the hydrogen of the 6-position hydroxyl group is replaced by an acyl group in the glucose unit.

  Only one kind of acyl group may be used for cellulose acylate, or two or more kinds of acyl groups may be used. When two or more kinds of acyl groups are used, it is preferable that one of them is an acetyl group. The sum of the degree of substitution of hydroxyl groups at the 2nd, 3rd and 6th positions by acetyl groups is DSA, and the sum of the degree of substitution of the hydroxyl groups at the 2nd, 3rd and 6th positions by acyl groups other than acetyl groups When DSB is DSB, the value of DSA + DSB is preferably 2.22 to 2.90, and particularly preferably 2.40 to 2.88.

  The DSB is preferably 0.30 or more, particularly preferably 0.7 or more. Further, 20% or more of DSB is preferably a substituent at the 6-position hydroxyl group, more preferably 25% or more, further preferably 30% or more, and particularly preferably 33% or more. Furthermore, the value of DSA + DSB at the 6-position of cellulose acylate is 0.75 or more, more preferably 0.80 or more, and particularly preferably cellulose acylate of 0.85 or more. When such cellulose acylate is used, a dope having excellent solubility can be prepared. In the case of using the cellulose acylate as described above, if a non-chlorine solvent is used, a dope having very excellent solubility, low viscosity, and excellent filterability can be prepared. .

  Cellulose, which is a raw material for cellulose acylate, may be obtained from either linter cotton or pulp cotton.

  The acyl group having 2 or more carbon atoms of cellulose acylate may be an aliphatic group or an aryl group, and is not particularly limited. For example, cellulose alkylcarbonyl ester, alkenylcarbonyl ester, aromatic carbonyl ester, aromatic alkylcarbonyl ester and the like can be mentioned. Further, each may have a substituted group. Preferred examples of these include 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, cyclohexanecarbonyl group, oleoyl group, benzoyl group, naphthylcarbonyl group, cinnamoyl group and the like. Among them, 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 that can be used in the present invention are described in paragraphs [0140] to [0195] of JP-A-2005-104148, and these descriptions also apply to the present invention. Can do.

  The solvent used as the dope material is preferably an organic compound that can dissolve the polymer used. However, in the present invention, the dope means a mixture obtained by dissolving or dispersing the polymer in a solvent, and therefore a solvent having low solubility with the polymer can also be used. Examples of the solvent that can be suitably used include aromatic hydrocarbons such as benzene and toluene, halogenated hydrocarbons such as dichloromethane, chloroform, and chlorobenzene, and alcohols such as methanol, ethanol, n-propanol, n-butanol, and diethylene glycol. , Ketones such as acetone and methyl ethyl ketone, esters such as methyl acetate, ethyl acetate and propyl acetate, ethers such as tetrahydrofuran and methyl cellosolve, and the like. Two or more kinds of solvents may be selected from these solvents and mixed solvents may be used. Among these, use of dichloromethane is preferable because a dope having excellent solubility can be obtained and the solvent in the cast film can be evaporated in a short time to form a film.

  As said halogenated hydrocarbon, a C1-C7 thing is used preferably. Furthermore, from the viewpoints of compatibility with the polymer, peelability which is an index of ease of peeling of the cast film peeled off from the support, mechanical strength of the film, optical properties, etc., dichloromethane has 1 to 5 carbon atoms. It is preferable to use one of these alcohols or a mixture of several alcohols. The content of alcohol is preferably 2 to 25% by weight, more preferably 5 to 20% by weight, based on the entire solvent. Specific examples of the alcohol include methanol, ethanol, n-propanol, isopropanol, n-butanol, etc. Among them, it is preferable to use methanol, ethanol, n-butanol, or a mixture thereof.

  Recently, a solvent composition not using dichloromethane has been proposed in order to minimize the influence on the environment. For this purpose, ethers having 4 to 12 carbon atoms, ketones having 3 to 12 carbon atoms, and esters having 3 to 12 carbon atoms are preferable, and these are preferably used by being mixed appropriately. These compounds may have a cyclic structure, and compounds having two or more functional groups of ether, ketone and ester, that is, any of -O-, -CO-, and -COO- are also used as a solvent. Can be used. In addition, the solvent may have another functional group such as an alcoholic hydroxyl group. In addition, when it has two or more types of functional groups, the carbon number should just be in the prescription | regulation range of the compound which has either functional group, and it does not specifically limit.

  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.

  Moreover, it is preferable to add fine particles to the dope for the purpose of preventing adhesion between films or adjusting the refractive index. As the fine particles, a silicon dioxide derivative is preferably used. The silicon dioxide derivative in the present invention includes silicon dioxide and a silicone resin having a three-dimensional network structure. As such a silicon dioxide derivative, it is preferable to use an alkylated surface. Fine particles that have been subjected to a hydrophobic treatment such as an alkylation treatment have excellent dispersibility in a solvent, so that a dope can be prepared without agglomeration of the fine particles, and a film can be produced. It is possible to produce a film with few state defects and high transparency.

  As described above, as the fine particles whose surface is alkylated, for example, Aerosil R805 (manufactured by Nippon Aerosil Co., Ltd.) which is commercially available as a silicon dioxide derivative having an octyl group introduced on its surface can be used. . In order to obtain a highly transparent film while ensuring the effect of adding fine particles, the fine particle content relative to the solid content of the dope is preferably 0.2% or less. Further, the average particle diameter is preferably 1.0 μm or less, more preferably 0.3 to 1.0 μm, and particularly preferably 0.4 to 0 so that the fine particles do not hinder the passage of light. .8 μm.

  As described above, in the present invention, it is preferable to prepare a dope using TAC as a polymer in order to obtain a highly transparent polymer film. In this case, it is preferable that the ratio of containing TAC is 5 to 40% by weight with respect to the total amount of the dope after mixing the solvent, additives and the like. More preferably, the ratio containing TAC is 15 to 30% by weight, and particularly preferably 17 to 25% by weight. Moreover, it is preferable that the ratio in which an additive (mainly a plasticizer) is contained shall be 1 to 20 weight% with respect to the whole solid content including the polymer, other additives, etc. which are contained in dope.

  Note that various additives such as solvents, plasticizers, ultraviolet absorbers, deterioration inhibitors, slipping agents, release accelerators, optical anisotropy control agents, retardation control agents, dyes, release agents, and the like, and fine particles are disclosed in JP-A-2005. No. 104148, paragraphs [0196] to [0516] describe in detail, and these descriptions can also be applied to the present invention. Further, it is a method for producing a dope using TAC. For example, materials, raw materials, additive dissolution methods and addition methods, filtration methods, defoaming, and the like are also disclosed in JP-A-2005-104148 [0517]. It is described in detail from paragraph to [0616] paragraph, and these descriptions can also be applied to the present invention.

DESCRIPTION OF SYMBOLS 10 Solution film forming equipment 13 Pin tenter 25 Wet film 25a Ear part 72 Pin 73 Pin plate 83 Jet wind washing area 202 Chamber 203a-203e, 204a-204e Nozzle 206 Supply pipe 209 Three-way valve 210 Suction pipe 212 Centrifuge 218 Piping 220 Controller 230 Jet air blowing unit 231 Upstream side air supply chamber 232 Downstream side air supply chamber 240, 242 Exhaust nozzle

Claims (10)

A supporting member for supporting both ends of the film being conveyed;
A circulating movement part for circulating and moving the carrier member between a carrier section where the carrier member carries the film and a release section where the carrier member releases the film;
A stretching / drying section that stretches at a constant widening ratio by gradually shifting the supporting member in a direction in which the film is widened, and is dried by blowing dry air with respect to the film in the carrying section. ,
A chamber covering the carrier member in the release section;
A jet air blowing unit that removes foreign matter adhering to the carrying member by blowing jet air against the carrying member that sequentially passes through the chamber;
A tenter device comprising: a foreign matter discharge section for discharging the foreign matter to the outside of the chamber.   The foreign matter discharge section includes an upstream suction chamber provided upstream of the jet wind blowing section and a downstream suction provided downstream of the jet wind blowing section with respect to the moving direction of the support member. The foreign matter is sucked into the chamber, and the sucked foreign matter is discharged out of the chamber together with the jet wind through a discharge nozzle attached to the upstream suction chamber and the downstream suction chamber. The tenter device according to claim 1.   The tenter device according to claim 2, wherein the upstream suction chamber and the downstream suction chamber are in a negative pressure state. A jet wind circulating section for collecting the jet wind blown to the support member in the chamber and circulating the jet wind by returning the collected jet wind to the chamber;
A jet wind escape section for escaping a part of the collected jet wind;
The control part which controls the temperature of the jet wind sprayed on the said supporting member by adjusting the air volume of the jet wind escaped by the said jet wind escape part is provided with any one of Claim 1 thru | or 3 characterized by the above-mentioned. Tenter device. A dope containing a polymer, a solvent, and an additive is cast on a support to form a cast film, the cast film is peeled off from the support as a wet film, and the wet film is spread in the width direction by a tenter device. In the solution casting equipment for producing a film by stretching and drying by blowing dry air,
The tenter device is
A supporting member for supporting both end portions of the wet film being conveyed;
A circulating movement unit that circulates and moves the support member between a support section in which the support member supports the wet film and a release section in which the support member releases the support of the wet film;
A chamber covering the carrier member in the release section;
By blowing jet air against the supporting member that sequentially passes through the chamber, the additive is liquefied or solidified, or foreign matter including debris and burrs that are generated when the supporting of the supporting member is started or released. A jet wind blowing part to be removed from the carrying member;
A solution film-forming facility, comprising: a foreign matter discharge section that discharges the foreign matter together with the jet wind to the outside of the chamber. The tenter device is
A separation unit for separating the foreign matter and the jet wind;
6. The apparatus according to claim 5, further comprising a downwardly inclined pipe that is provided so as to be gradually lowered from the foreign matter discharge portion toward the separation portion and that sends the foreign matter from the foreign matter discharge portion to the separation portion. Solution casting equipment. The tenter device is
A jet wind circulating section for collecting the jet wind blown to the support member in the chamber and circulating the jet wind by returning the collected jet wind to the chamber;
A jet wind escape section for escaping a part of the collected jet wind;
A controller that controls the temperature of the jet wind blown to the support member by adjusting the amount of jet wind that is released by the jet wind escape section;
The said control part controls the temperature of the said jet wind in the range which is the temperature exceeding the melting | fusing point of the said additive, and is less than the heat-resistant temperature of the various apparatuses in the said tenter apparatus. The solution casting apparatus described.   8. The solution casting apparatus according to claim 7, wherein the temperature of the jet air is 49 ° C. or more and is controlled to 120 ° C. or less, which is a heat resistant temperature of various devices in the tenter device.   9. The solution casting apparatus according to claim 5, wherein the tenter device is a pin tenter including a pin and a pin plate in which a large number of pins are planted as the support member. The support member is circulated and moved between a section in which both side ends of the film being transported are supported by the support member and a release section in which the support of the film by the support member is released,
For the film in the carrying section, the film is stretched at a constant widening ratio by gradually shifting the carrying member in the direction in which the film is widened, and dried by blowing dry air,
In the chamber covering the carrier member in the release section, by blowing jet air against the carrier member that sequentially passes through the chamber, foreign matter attached to the carrier member is removed,
A foreign matter removing method in a tenter device, wherein the foreign matter is discharged out of the chamber.

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