JP2019168549A - Method for producing polarizer and polarizing plate - Google Patents

Abstract

To provide a method for producing a polarizer and a polarizing plate capable of performing efficient start-up and/or stopping as a result leading efficiently implementing the method.SOLUTION: A method for producing the polarizer includes a start-up step for passing the starting end of a long material film from an inlet to an outlet of a processing path; and a continuous processing step of continuously conveying the material film along the processing path after completion of the start-up step. The processing path includes one or more immersion processing zones; the immersion processing zone includes an immersion path; a downstream feeder and upstream feeder are provided in each of the upstream and downstream sides of the immersion treatment zone; the start-up step makes the material film reach the immersion path and the tension of the material film in the immersion treatment zone be adapted to decrease: and a step for increasing the relative feed rate of the downstream feeder to the upstream feeder.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a polarizer and a method for producing a polarizing plate.

  As a kind of optical film, a polarizing plate is widely used. The polarizing plate is a film having a function of polarizing, that is, a function of separating transmitted light into linearly polarized light. As an example of a polarizing plate, what is provided with the polarizer which is a layer which has this polarization function, and the protective film which protects a polarizer is known. In the manufacture of a general polarizer, a film including a layer containing polyvinyl alcohol or a modified product thereof is used as a material film, and the material film is processed (for example, Patent Document 1).

  In order to increase the efficiency of the manufacturing process, the material film is usually prepared as a long film, and the processing of the material film is usually performed by continuously conveying the material film in the processing path. In addition, as shown in the example of Patent Document 1, such treatment usually includes many steps of immersing the material film in a liquid, such as dyeing, stretching, and washing.

  Liquids used for processing material films often contain highly reactive components and are easily vaporized because they are heated to temperatures above room temperature during processing. For this reason, a surrounding body surrounding the processing path and a device for exhausting the liquid vaporized material are usually provided around the processing path, thereby limiting the contamination by the liquid and the vaporized material.

  Usually, a plurality of zones for performing each processing are set in the processing path. At the upstream and downstream boundaries of the zone, a feeding device such as a nip roll that grips the film and adjusts the feeding speed is provided. Depending on the setting of the operating conditions of the feeding device, the transport speed and tension in each zone are set. It is determined.

  For example, in a zone in which a process involving stretching or shrinking of the material film is performed, the ratio of the feeding speed of the downstream feeding device to the feeding speed of the zone upstream feeding device is set at a ratio corresponding to the stretching or shrinking ratio. Control in which the feed speed of the feed device is set and maintained at a constant value is also called draw control.

  In manufacturing a polarizer, prior to a continuous processing step, a start-up step, that is, a step of passing the starting end of the material film from the entrance to the exit of the processing path is necessary. The start-up process is usually performed by inserting a material film into a feeding device that is draw-controlled at a speed set for the processing process as described above.

JP 2017-204209 A

  Polyvinyl alcohol is a relatively soft material, and by being immersed in a liquid, it is further softened and undergoes a large dimensional change under a low tension load. Therefore, in manufacture of a polarizer, the malfunction of conveyance of a material film can generate | occur | produce easily. In particular, in the start-up process, since the properties of the material film change greatly, it is difficult to avoid the occurrence of problems and carry it. Therefore, particularly in the start-up process, a long work time and complicated labor are required, and a lot of material film loss that cannot be made in the product occurs.

  For example, if the film is softer than the polarizer material film, the film guiding device provided in the processing path area is operated to access the inside of the enclosure around the processing path and to perform manual work. The insertion can be easily performed by an automated operation without accompanying, but in the case of a material film of a polarizer, it is difficult to avoid problems in such an automated operation.

  In order to avoid problems in the start-up process or to deal with problems that have occurred, it may be necessary for an operator to access the processing path and work manually by hand or via an instrument. Such work requires the opening of the enclosure around the processing path and the use of protective equipment to protect the worker from liquids and their vapors, and due to the many moving parts and liquids in the processing path. It is necessary to carry out the work carefully to avoid the occurrence of accidents by workers. Therefore, it is difficult to perform such work efficiently.

  The same problem as that at the time of start-up is that the material film is discharged from the processing path after completion of the shutdown process, that is, the continuous processing process, and the apparatus for processing is in an easy-to-restart state. It also occurs when performing the process of stopping.

  Therefore, the object of the present invention is to efficiently start up and / or lower, with less labor, required time and loss of material film, and as a result, it is possible to efficiently manufacture polarizers and polarizing plates. It is providing the manufacturing method of a polarizer and a polarizing plate which is.

As a result of studies to solve the above problems, the present inventor has conceived that specific control that has not been performed in the conventional startup and shutdown processes is performed in the startup and / or shutdown processes. The present invention has been completed.
That is, the present invention is as follows.

[1] A start-up process in which a starting end of a long material film is inserted into a processing path from an inlet to an outlet thereof, and after the start-up process is completed, the material film is continuously moved along the processing path. A method for producing a polarizer, comprising a continuous processing step of conveying,
The material film is a film including a layer containing polyvinyl alcohol or a modified product thereof,
The treatment path includes one or more immersion treatment zones,
The immersion treatment zone includes an immersion path through which the material film passes through a liquid bath,
An upstream feeding device capable of adjusting the feeding speed of the material film carried into the immersion treatment zone, and the material film carried out from the immersion treatment zone, on the upstream side and the downstream side of the immersion treatment zone, respectively. A downstream feeding device capable of adjusting the feeding speed of
The start-up step is adapted to allow the material film to reach the immersion path and to reduce the tension of the material film in the immersion treatment zone, and to feed the downstream-side feeder relative to the upstream-side feeder. A production method comprising a speed adaptation step (A) for increasing the speed.
[2] The manufacturing method according to [1], wherein a tension applied to the material film is detected, and the speed adaptation step (A) is performed according to the detected tension.
[3] The manufacturing method according to [1] or [2], wherein the tension is detected by a dancer roller device provided in a portion other than the immersion path in the immersion treatment zone.
[4] The manufacturing method according to [3], wherein the speed adaptation step (A) includes adjustment of a path length in the immersion treatment zone by the dancer roller device.
[5] In the speed adaptation step (A), after the starting end portion of the material film reaches the immersion path, the downstream side feeding is adapted to the degree of progress of the starting end portion in the immersion treatment zone. The manufacturing method according to any one of [1] to [4], which is performed by increasing the relative feed speed of the apparatus.
[6] As a process prior to the startup process,
A preliminary insertion step in which a leading end of a long leader film is inserted from the inlet to the outlet of the processing path so that the leader film extends from the inlet to the outlet of the processing path; and an end of the leader film Connecting step (A) with the starting end of the material film to form a series of rising films
Further including
The manufacturing method according to any one of [1] to [5], wherein the startup step includes conveying the startup film.
[7] After the continuous processing step, further includes a falling step of discharging the material film from the processing path, the falling step,
A connecting step (B) in which a terminal portion of the material film is connected to a starting end portion of a long tailor film to form a series of falling films; and the trailing film is conveyed, and the tailor film reaches the immersion path. A speed adaptation step (B) adapted to increase the tension of the falling film in the immersion treatment zone and to reduce the relative feeding speed of the downstream feeding apparatus with respect to the upstream feeding apparatus;
The manufacturing method of any one of [1]-[6] containing.
[8] A polarizer comprising: a continuous processing step of continuously conveying a long material film along a processing path; and a falling step of discharging the material film from the processing path after the continuous processing step. A manufacturing method comprising:
The material film is a film including a layer containing polyvinyl alcohol or a modified product thereof,
The treatment path includes one or more immersion treatment zones,
The immersion treatment zone includes an immersion path through which the material film passes through a liquid bath,
An upstream feeding device capable of adjusting the feeding speed of the material film carried into the immersion treatment zone, and the material film carried out from the immersion treatment zone, on the upstream side and the downstream side of the immersion treatment zone, respectively. A downstream feeding device capable of adjusting the feeding speed of
The falling step is
A connecting step (B) in which a terminal portion of the material film is connected to a starting end portion of a long tailor film to form a series of falling films; and the trailing film is conveyed, and the tailor film reaches the immersion path A speed adaptation step (B) adapted to increase the tension of the falling film in the immersion treatment zone and to reduce the relative feeding speed of the downstream feeding apparatus with respect to the upstream feeding apparatus;
Manufacturing method.
[9] Manufacture of a polarizing plate including a step of obtaining a polarizer by the manufacturing method according to any one of [1] to [8], and a bonding step of bonding the polarizer and the protective film. Method.

  According to the present invention, efficient startup and / or shutdown can be performed with less labor, required time, and loss of material film. As a result, it is possible to efficiently manufacture a polarizer and a polarizing plate. A method for producing a polarizer and a polarizing plate is provided.

FIG. 1 is a side view schematically showing an example of a processing apparatus constituting a processing path used in the method for manufacturing a polarizer of the present invention. FIG. 2 is a block diagram schematically showing the processing path of the processing apparatus shown in FIG. FIG. 3 is a bar graph showing an example of control of the feed speed of the nip roll in the processing path shown in FIG. FIG. 4 is a block diagram schematically showing the processing path of the processing apparatus shown in FIG. FIG. 5 is a bar graph showing an example of control of the feed speed of the nip roll in the processing path shown in FIG. FIG. 6 is a block diagram schematically showing the processing path of the processing apparatus shown in FIG. FIG. 7 is a bar graph showing an example of control of the nip roll feed rate in the processing path shown in FIG.

  Hereinafter, the present invention will be described in detail with reference to embodiments and examples. However, the present invention is not limited to the following embodiments and exemplifications, and can be implemented with arbitrary modifications without departing from the scope of the claims of the present invention and the equivalents thereof.

  In the following description, the “long” film means a film having a length of 5 times or more, preferably 10 times or more, and specifically a roll. A film having such a length that it can be wound up and stored or transported. The upper limit of the length of the long film is not particularly limited, and can be, for example, 100,000 times or less with respect to the width.

  In the following description, the “end portion” of a long film is an end portion in the longitudinal direction unless otherwise specified.

  In the following description, the “polarizing plate” includes not only a rigid member but also a flexible member such as a resin film, unless otherwise specified.

[1. Overview of manufacturing method)
The manufacturing method of the polarizer of the present invention includes a specific startup process and / or a shutdown process, and a continuous processing process. The method for producing a polarizer of the present invention can optionally include a preliminary insertion step and a connecting step (A) as a step preceding the start-up step.

  The start-up step is a step of passing the starting end portion of the long material film from the entrance to the exit of the processing path. On the other hand, in the continuous processing step, after the start-up step is completed, the material film is continuously conveyed along the processing path. That is, the start-up process is a process for performing preparations prior to the continuous processing process, and the polarizer is not yet manufactured at the stage of the start-up process, but is manufactured as a result of the subsequent continuous processing process.

  The falling step is a step of discharging the material film from the processing path after the continuous processing step. The falling step may be intended to stop the manufacturing apparatus in a state where re-starting is easy after the manufacture of the polarizer by the continuous processing step is completed.

  In the present application, the path defined by the term “processing path” may be all of the paths for performing the processes necessary for manufacturing the polarizer, or may be a part thereof. For example, in manufacturing a polarizer, a path including a process of immersing a material film in a liquid, such as dyeing, stretching, and washing, is referred to as a “processing path”, and other processes (for example, a path other than the “processing path”) (for example, , Drying, inspection, pasting with other members, etc.).

[2. First embodiment]
FIG. 1 is a side view schematically showing an example of a processing apparatus constituting a processing path used in the method for manufacturing a polarizer of the present invention. Below, the manufacturing method of the polarizer of this invention is demonstrated with reference to the example using this processing apparatus as 1st embodiment of this invention.

  In FIG. 1, the processing apparatus 10 includes a material film feeding apparatus 101, a group of apparatuses constituting a processing path in the processing path area 102, and an intermediate winding apparatus 103. In FIG. 1, the processing path is shown as a path through which the long material film 104 is conveyed in the processing path area 102.

  In the production method of the present invention, the treatment path includes one or more immersion treatment zones, and the immersion treatment zone includes an immersion path through which the material film passes through the liquid bath. In the example of the first embodiment, the processing apparatus 10 includes three tanks 121, 131, and 141 in the processing path, and stores a liquid for processing the material film in these tanks. An immersion path can be provided by configuring a path for transporting the film in these tanks.

  By sequentially immersing the material film 104 in the liquid bath in such an immersion path, processing necessary for making the material film a polarizer, such as dyeing, stretching, and washing, can be sequentially performed in a continuous processing step. . In 1st embodiment, although the example which has only three tanks as a tank is shown, this invention is not restricted to this, The tank which comprises a processing path may be more numerous, and it may be fewer. Also good.

  The processing apparatus 10 includes one or a plurality of guide rolls 125, 135, and 145 inside each of the tanks 121, 131, and 141. By guiding the film with the guide roll and configuring the treatment path in the liquid stored in the tanks 121, 131 and 141, an immersion path for immersing the material film in the liquid can be configured.

  Specifically, among the processing paths, the path from the immersion path start position SP21 to the immersion path end position SP22 is the immersion path Z22 by the tank 121, and the path from the immersion path start position SP31 to the immersion path end position SP32 is An immersion path Z32 by the tank 131 is formed, and a path from the immersion path start position SP41 to the immersion path end position SP42 is an immersion path Z42 by the tank 141.

  By appropriately adjusting the number and arrangement of the guide rolls in the immersion path, processing conditions such as processing time can be adjusted. The guide roll may be a free roll that freely rotates following the film, or may be a drive roll driven by a driving device, and if necessary, nip the film in the same manner as the nip roll and stretch it in a tank. It may be a roll that performs the above operations.

  The processing device 10 includes a plurality of nip rolls N21, N31, N41, and N51 as feeding devices in the processing path. Films (leader film, material film, tailor film, etc.) passed through the processing path region 102 are supplied to the inlet 111 and sent to the outlet 112 by a plurality of nip rolls N21, N31, N41, and N51.

  The nip roll N21 includes a pair of an upper roll 122 and a lower roll 123, the nip roll N31 includes a pair of an upper roll 132 and a lower roll 133, and the nip roll N41 includes a pair of an upper roll 142 and a lower roll 143. The film is nipped by each pair of upper roll and lower roll, and the upper roll and lower roll are driven by an appropriate driving device (not shown), thereby applying tension to the film from the upstream side to the downstream side. The film can be transported.

  In the manufacturing method of the present invention, the upstream side and the downstream side of the immersion treatment zone are respectively transported from the upstream feed device capable of adjusting the feed speed of the material film carried into the immersion treatment zone, and from the immersion treatment zone. A downstream side feeding device capable of adjusting the feeding speed of the material film is provided. In the processing path in the example of the first embodiment, a pair of adjacent nip rolls defines an immersion processing zone including each of the immersion paths.

  Specifically, the treatment path in the example of the first embodiment includes an immersion treatment zone Z21 including the immersion path Z22, an immersion treatment zone Z31 including the immersion path Z32, and an immersion treatment zone Z41 including the immersion path Z42. The processing zone Z21 is defined in the path from the nip position of the nip roll N21 as the upstream side feeding device to the nip position of the nip roll N31 as the downstream side feeding device, and the immersion processing zone Z31 is the nip roll N31 as the upstream side feeding device. Is defined in the path from the nip position of the nip roll N41 as the downstream side feed device to the nip position of the nip roll N41 as the downstream side feed device. It is defined in the path to the nip position.

  The processing device 10 includes a dancer roller device in each immersion processing zone. In the present application, the term “dancer roller device” is a device including one or more rollers and a shaft member thereof, and the shaft member is supported so as to be swingable in use. As a structure of the dancer roller device, a structure including a dancer roller or accumulator used in general film conveyance and its accessories can be appropriately adopted. For example, the shaft member of the roller is supported by a track device such as a pair of rails directly or via an appropriate bearing at both ends in the rotational axis direction. The track device can support the shaft member such that the shaft member can swing on a linear or curved track in any direction perpendicular to the rotation axis direction of the roller.

  The dancer roller device may further include a biasing device that can bias a force in a direction along the peristaltic motion of the track device with respect to the shaft member. By performing such urging, tension can be applied to the film. If the direction of the biasing force is required to be downward (the direction of gravity), such a biasing can be achieved by the weight of the roller and the shaft member, but it is necessary to adjust the biasing force. In some cases and when the direction of the desired biasing force is other than downward, the biasing device can perform biasing suitable for applying tension to the film.

  The dancer roller device may further include a detection device that detects the position of the shaft member in the track device. By having such a detection device, it is possible to obtain information on whether the tension on the film is excessive or insufficient via the dancer roller device. Specifically, when the film is loosened and the tension on the film becomes too small, the position of the shaft member moves in the biased direction (upward in the example of FIG. 1), the film is tensioned, When the tension on the shaft member is excessive, the position of the shaft member can move in the direction opposite to the biased direction (downward in the example of FIG. 1). Information about film tension can be obtained.

  In the example of the first embodiment, the processing apparatus 10 is provided in a portion downstream of the immersion path Z32 in the immersion roller zone D31 and the dancer roller device D21 provided in the downstream area of the immersion path Z22 in the immersion zone Z21. And a dancer roller device D41 provided in a portion downstream of the immersion path Z42 in the immersion treatment zone Z21.

  The dancer roller device D21 includes a roller 129 and a shaft member 128 that functions as a rotation shaft of the roller 129. The dancer roller device D21 further includes a bearing (not shown) that supports the shaft member 128, a rail 127 that supports the bearing so as to be swingable in the vertical direction, and a biasing device (not shown) that can bias upward force on the bearing. And a detecting device for detecting the position of the shaft member. Similarly, the dancer roller devices D31 and D41 also include rollers 139 and 149, shaft members 138 and 148, bearings, rails 137 and 147, a biasing device, and a detection device.

  The processing path region 102 may be a region surrounded by the surrounding body 107 on the side surface and surrounded by the exhaust duct 108 on the upper surface. By setting it as such an enclosed area | region, the contamination by the liquid used in a process path | route and its vaporized material is controllable. The processing apparatus also includes a lift 109 that can adjust the vertical installation positions of the tanks 121, 131, and 141, thereby facilitating use and maintenance of the processing apparatus 10.

  The processing apparatus 10 may further include an arbitrary apparatus that can be used for performing the manufacturing method. For example, a film guiding device (not shown) may be provided in the processing path region. For example, a device for guiding the film may be provided in a route such as a route from the nip roll to the guide roll, a route between the guide rolls, a route from the guide roll to the dancer roller device, and a route from the dancer roller device to the next nip roll.

[2.1. Startup process, preliminary insertion process and connection process (A)]
In the start-up process, the starting end of the long material film is passed from the entrance to the exit of the processing path. The start-up process includes a speed adaptation process. The speed adaptation process is a process in which the material film reaches the immersion path and is adapted to decrease the tension of the material film in the immersion treatment zone, and the relative feed speed of the downstream feeder with respect to the upstream feeder is increased. is there. In this application, in order to distinguish from the speed adaptation process in a fall process, the speed adaptation process in a startup process may be called speed adaptation process (A). On the other hand, the speed adaptation process in the falling process may be referred to as a speed adaptation process (B).

  An example of the speed adaptation process will be described with reference to FIGS. 2 to 7 in addition to FIG. 2, 4 and 6 are configuration diagrams schematically showing the processing path of the processing apparatus shown in FIG. In FIG. 2, FIG. 4 and FIG. 6, the processing path along which the material film 104 is conveyed is schematically shown as a straight line for convenience of explanation. FIGS. 3, 5 and 7 are bar graphs showing an example of control of the feed speed of the nip roll in the processing path shown in FIGS.

  2, 4 and 6, the nip positions by the nip rolls N21, N31, N41 and N51 are indicated as nip positions NP21, NP31, NP41 and NP51 by arrows. The path from the nip position NP21 to NP31 is an immersion treatment zone Z21, and the immersion treatment zone Z21 includes an immersion route Z22 by the tank 121. The path from the nip position NP31 to NP41 is an immersion treatment zone Z31, and the immersion treatment zone Z31 includes an immersion route Z32 by the tank 131. The path from the nip position NP41 to NP51 is an immersion treatment zone Z41, and the immersion treatment zone Z41 includes an immersion route Z42 by the tank 141.

  2, 4, and 6, the immersion path start position SP21 and the immersion path end position SP22 by the tank 121, the immersion path start position SP31 and the immersion path end position SP32 by the tank 131, and the immersion path start position SP41 by the tank 141 are illustrated. The immersion path end position SP42 is indicated by an arrow with the symbol. Further, the positions where the film is put on the dancer roller devices D21, D31 and D41 and in contact with the film are indicated by dancer roller device positions DP21, DP31 and DP41 by arrows.

[2.1.1. Connection step (A)]
In this invention, the connection process which connects the terminal part of a leader film with the start part of a material film, and makes it a series of starting films can be performed. In the example of the first embodiment shown in FIGS. 2 to 7, a rising film in which the terminal portion of the leader film 105 and the starting end portion of the material film 104 are connected by the connecting portion 106 is used. In this application, in order to distinguish from the connection process in a fall process, the connection process in a starting process may be called a connection process (A). On the other hand, the connecting step in the falling step may be referred to as a connecting step (B).

[2.1.2. (Preliminary insertion process)
Prior to the state shown in FIG. 2, a preliminary insertion process is performed. That is, the leading end portion of the leader film 105 is inserted from the inlet 111 to the outlet 112 of the processing path. By adopting the leader film 105 having a low degree of softening by the liquid in the tank, the leader film 105 can be easily inserted. For example, by operating a guidance device (not shown) provided in the processing path region, it is possible to perform insertion through access to the inside of the enclosure 102 and operation without manual operation. The preliminary insertion step can be performed before or after the connecting step, or in parallel with the connecting step.

  After completion of the preliminary insertion process, the leader film 105 is attached to the core member of the intermediate winding device 103. As the intermediate winding device 103 rotates in the direction of arrow A <b> 3, the leader film 105 is wound by the intermediate winding device 103. By such winding, the rising film is conveyed in the arrow A1 direction, and the connecting portion 106 moves in the arrow A1 direction.

  Until the connecting portion 106 reaches the start position SP21 of the immersion path Z22, the rising film can be conveyed at the same feed speed from the inlet 111 to the outlet 112. Specifically, by adopting a low degree of softening by the liquid in the tank as the leader film 105, the leader film 105 can be transported in a state where there is substantially no elongation when passing through the immersion path. . In that case, the feed speeds NV21, NV31, NV41, and NV51 by the nip rolls N21, N31, N41, and N51 can all be equal speeds V1, as shown by the solid line in FIG.

[2.1.3. Speed adaptation process in the immersion treatment zone Z21 (A)]
After the connecting portion 106 reaches the immersion path start position SP21 and enters the state shown in FIG. 2, when the rising film is further conveyed in the direction of the arrow A1, the connecting portion 106 moves in the immersion path Z22, and the immersion path Z22. , The length occupied by the material film 104 increases. Since the material film 104 is softened by the liquid in the tank 121 in the immersion path Z <b> 22, the material film 104 is easily stretched by the tension applied to convey the material film 104, and its length is extended. Therefore, the tension | tensile_strength of the material film 104 in the immersion process zone Z21 falls. This is adapted to increase the relative feed speed of the downstream feed device relative to the upstream feed device. By such an operation, the speed adaptation step in the immersion treatment zone Z21 is achieved.

  In the example shown in FIG. 2, the material film 104 in the immersion path Z <b> 22 until the connecting portion 106 of the rising film moves from the immersion path start position SP <b> 21 to the immersion path end position SP <b> 22 as indicated by the broken line 106-22. Continues to increase, thereby gradually reducing the tension of the material film 104 in the immersion treatment zone Z21. Failure to adapt to such a gradual decrease in tension will cause problems such as loosening of the material film 104, making it difficult to easily guide the rising film to the outlet, so an adaptation to such a gradual decrease is required.

  Therefore, in order to adapt to such gradual reduction, the feed speed NV21 of the nip roll N21 remains unchanged while the connecting portion 106 moves from the immersion path start position SP21 to the immersion path end position SP22, while the downstream side of the nip roll N21 is not changed. The feed speeds NV31, NV41, and NV51 of the nip rolls, that is, the nip rolls N31, N41, and N51, are gradually increased from V1 to V2 as indicated by broken lines in FIG. This achieves an increase in relative feed rate that is adapted to a decrease in tension due to the extension of the material film 104 by the liquid in the bath 121.

  Until the connecting portion 106 passes through the end position SP22 of the immersion path Z22 and reaches the start position SP31 of the immersion path Z32, the conveyance of the rising film is not accompanied by a change in the feed speed, and NV21 = V1, NV31 = NV41. = NV51 = V2 can be maintained. Further, regarding the feeding speeds NV21 and NV31 of the nip rolls N21 and N31, the states of the speeds NV21 = V1 and NV31 = V2 can be maintained even after the connecting portion 106 passes the start position SP31 of the immersion path Z32.

  However, the tension of the material film 104 in the immersion treatment zone Z21 may change according to changes in various conditions. Such a change can be mitigated by a change in the position of the shaft member 128 of the dancer roller device D21 provided at the position DP21. That is, the position change adjusts the path length in the immersion treatment zone by the dancer roller device D21, whereby the tension is adjusted to a higher degree and the start-up process can be performed smoothly.

  Further, the change in tension is detected by monitoring the change in position of the shaft member 128 of the dancer roller device D21 or by monitoring the change in tension using another tension measuring device, and accordingly, the nip roll N21 and the corresponding change are detected. The relative feed speed of the downstream nip roll can be adjusted. By such adjustment, it is possible to suppress the change in tension from exceeding the range that can be relaxed by the dancer roller device D21.

[2.1.4. Speed adapting step (A) in the immersion treatment zone Z31]
After the connecting portion 106 reaches the immersion path start position SP31 and enters the state shown in FIG. 4, when the rising film is further conveyed in the direction of the arrow A1, the connecting portion 106 moves in the immersion path Z32, and the immersion path Z32. , The length occupied by the material film 104 increases. Since the material film 104 is softened by the liquid in the tank 131 in the immersion path Z32, the material film 104 is easily stretched by the tension applied to convey the material film 104, and its length is extended. Therefore, the tension | tensile_strength of the material film 104 in the immersion process zone Z31 falls. This is adapted to increase the relative feed speed of the downstream feed device relative to the upstream feed device. By such an operation, the speed adaptation process in the immersion treatment zone Z31 is achieved.

  In the example shown in FIG. 4, the material film 104 in the immersion path Z <b> 32 until the connecting portion 106 of the rising film moves from the immersion path start position SP <b> 31 to the immersion path end position SP <b> 32 as indicated by the broken line 106-32. The length that occupies continues to increase. With this increase, the tension of the material film 104 in the immersion treatment zone Z31 is gradually reduced as in the immersion treatment zone Z21, and adaptation to such a reduction is required.

  Therefore, in order to adapt to such gradual decrease, the feed speed NV21 of the nip roll N21 and the feed speed NV31 of the nip roll N31 are not changed until the connecting portion 106 moves from the immersion path start position SP31 to the immersion path end position SP32. On the other hand, the nip rolls downstream of the nip roll N31, that is, the feed speeds NV41 and NV51 of the nip rolls N41 and N51 are gradually increased from V2 to V3 as indicated by broken lines in FIG. This achieves an increase in relative feed rate that is adapted to a decrease in tension due to the extension of the material film 104 by the liquid in the bath 131.

  Until the connecting portion 106 passes the end position SP32 of the immersion path Z32 and reaches the start position SP41 of the immersion path Z42, the conveyance of the rising film is not accompanied by a change in the feeding speed, and NV21 = V1, NV31 = V2 , NV41 = NV51 = V3 can be maintained. Further, regarding the feed speeds NV21, NV31, and NV41 of the nip rolls N21, N31, and N41, the speeds NV21 = V1, NV31 = V2, and NV41 = V3 even after the connecting portion 106 passes the start position SP41 of the immersion path Z42. Can be maintained.

  However, the tension of the material film 104 in the immersion treatment zone Z31 may change according to changes in various conditions. Such a change can be alleviated by a change in the position of the shaft member 138 of the dancer roller device D31 provided at the position DP31. That is, the position change adjusts the path length in the immersion treatment zone by the dancer roller device D31, whereby the tension is adjusted to a higher degree and the start-up process can be performed smoothly.

  In addition, the change in tension is detected by monitoring the change in position of the shaft member 138 of the dancer roller device D31 or by monitoring the change in tension with another tension measuring device, and accordingly, the nip roll N31 and the The relative feed speed of the downstream nip roll can be adjusted. By such adjustment, it is possible to prevent the change in tension from exceeding the range that can be relaxed by the dancer roller device D31.

[2.1.5. Speed adaptation process in the immersion treatment zone Z41 (A)]
After the connecting portion 106 reaches the immersion path start position SP41 and enters the state shown in FIG. 6, when the rising film is further conveyed in the arrow A1 direction, the connecting portion 106 moves in the immersion path Z42, and the immersion path Z42. , The length occupied by the material film 104 increases. Since the material film 104 is softened by the liquid in the tank 141 in the immersion path Z42, the material film 104 is easily stretched by the tension applied to transport the material film 104, and the length thereof is extended. Therefore, the tension | tensile_strength of the material film 104 in the immersion process zone Z41 falls. This is adapted to increase the relative feed speed of the downstream feed device relative to the upstream feed device. By such an operation, the speed adaptation step in the immersion treatment zone Z41 is achieved.

  In the example shown in FIG. 6, the material film 104 in the immersion path Z <b> 42 until the connecting portion 106 of the rising film moves from the immersion path start position SP <b> 41 to the immersion path end position SP <b> 42 as indicated by the broken line 106-42. The length that occupies continues to increase. With this increase, the tension of the material film 104 in the immersion treatment zone Z41 is gradually reduced as in the immersion treatment zone Z21, and adaptation to the gradual reduction is required.

  Therefore, in order to adapt to such gradual reduction, the nip roll N21 feed speed NV21, the nip roll N31 feed speed NV31, and the nip roll N41 of the connecting portion 106 are moved from the immersion path start position SP41 to the immersion path end position SP42. While making the feed speed NV41 unchanged, the nip roll downstream of the nip roll N41, that is, the feed speed NV51 of the nip roll N51 is gradually increased from V3 to V4 as shown by the broken line in FIG. This achieves an increase in relative feed rate that is adapted to a decrease in tension due to the extension of the material film 104 by the liquid in the bath 141.

  After the connecting portion 106 has passed the end position SP42 of the immersion path Z42, the conveyance of the rising film is not accompanied by a change in the feeding speed, and the states of NV21 = V1, NV31 = V2, NV41 = V3, and NV51 = V4 are maintained. Can be maintained.

  However, the tension of the material film 104 in the immersion treatment zone Z41 may change according to changes in various conditions. Such a change can be alleviated by a change in the position of the shaft member 148 of the dancer roller device D41 provided at the position DP41. That is, the position change adjusts the path length in the immersion treatment zone by the dancer roller device D41, whereby the tension is adjusted to a higher degree and the start-up process can be performed smoothly.

  Further, the change in tension is detected by monitoring the change in position of the shaft member 148 of the dancer roller device D41 or by monitoring the change in tension with another tension measuring device, and accordingly, the nip roll N41 and the The relative feed speed of the downstream nip roll can be adjusted. By such adjustment, it is possible to suppress the change in tension from exceeding a range that can be relaxed by the dancer roller device D41.

  After the connecting portion 106 passes the end position SP42 of the immersion path Z42, the leader film 105 is all taken out from the outlet 112 and taken up by the intermediate winding device 103 by continuing the conveyance of the rising film. As a result, the material film 104 occupies the entire processing path from the inlet 111 to the outlet 112. The material film 104 carried out from the outlet 112 can be a film that has been processed by the immersion treatment zones Z21, Z22, and Z23.

  The state of the material film 104 carried out from the outlet 112 is inspected to determine whether the quality of the material film is good or not (that is, whether the material film has a desired quality that can be used in a process subsequent to the processing by the processing path). Can be judged. As a result of the determination, if it is determined as NO, the processing conditions in the processing path can be adjusted to be a material film of a desired quality.

  As a result of the determination, if it is determined to be good, the transfer process after the exit 112 can be switched. Specifically, the conveyance path of the material film 104 is switched from the conveyance path to the intermediate winding device 103 indicated by the arrow A2 in FIG. 1 to the conveyance path to the next process indicated by the arrow A4. The process can be terminated and a continuous process can be started. For such switching, if necessary, an accumulator (not shown) is used downstream from the outlet 112 to perform switching while maintaining the conveying speed of the material film 104 in the processing path, thereby smoothly continuously processing. The process can be started. The apparatus for switching the conveyance path while maintaining the conveyance speed is not limited to an accumulator, and other apparatuses may be employed. For example, using a web butt joining apparatus as disclosed in JP-A-6-171806, etc., switching is performed while maintaining the conveying speed of the material film 104 in the processing path, thereby smoothly performing the continuous processing step. Can start.

[2.1.6. Control in speed adaptation process (A)]
In the speed adaptation step, the relative feed rate change amount (V2-V1 value, V3-V2 value, and V4-V3 value in the above example) is determined in each immersion treatment zone. It is possible to detect the tension applied to the, and perform it according to the detected tension. As described above, the tension can be detected by monitoring the change in the position of the shaft member of the dancer roller device or by monitoring the change in tension using another tension measuring device. The specific tension in each immersion treatment zone can be adjusted to, for example, a tension that enables smooth conveyance. Moreover, when extending | stretching a material film with the load of tension | tensile_strength, it can be set as the tension | tensile_strength suitable for this extending | stretching.

  The tension is preferably detected by a dancer roller device provided in a portion other than the immersion path in the immersion treatment zone as in the above example. When the dancer roller device is provided in a part in the immersion path, the length of the immersion path varies depending on the position of the shaft member, and the length of the material film is frequently increased in the immersion treatment zone. Fluctuates. Such frequent fluctuations can affect the optimum relative feed rate value. On the other hand, when the dancer roller device is provided in a portion other than the immersion path, the change in the position of the shaft member does not affect the length of the immersion path. Therefore, a more stable process can be performed. Further, by providing the dancer roller device in a portion other than the immersion path, smooth tension can be detected without being affected by the liquid in the bag, and the operation and maintenance of the dancer roller device are facilitated.

  As another example of adjusting the amount of change in the relative feed rate, if the relationship between the length of the material film in the immersion path and the degree of change in the tension is known and predictable, the beginning of the material film After the part reaches the immersion path, it is possible to adjust the relative feed rate in accordance with the degree of progress in the immersion treatment zone of the starting end part. Specifically, the position information of where the connecting portion is located in the processing path is obtained by measurement or calculation, and based on that, the length occupied by the material film in each immersion path is obtained, and the tension corresponding to the length is determined. The degree of decrease can be predicted, and the relative feed rate can be adjusted based on the prediction.

  By performing the speed adaptation process described above, in the production of a polarizer using a relatively soft material as the material film, it is possible to reduce problems in conveying the material film. In addition, the operation from the start-up process to the continuous processing process can be easily achieved by an operation without access to the inside of the enclosure and manual operation. In addition, as described above, by performing the speed adaptation process in each of the plurality of immersion treatment zones, the immersion treatment under the same or different operating conditions can be efficiently performed while reducing defects in a series of treatment paths. Can be implemented automatically.

[2.2. (Continuous treatment process)
After the start of the continuous processing step, the material film 104 conveyed along the conveyance path indicated by the arrow A4 is subjected to further steps (for example, drying, inspection, pasting with other members, etc.) as necessary, Thereby, a polarizer is manufactured. On the other hand, the leader film 105 and the material film 104 taken up by the intermediate take-up device 103 are reused as they are, used for a new film manufacturing material, or discarded.

  In the conveyance of the material film in the continuous processing step, the feeding speed of each feeding device can be appropriately adjusted to a speed suitable for performing the continuous processing step. For example, continuous processing can be efficiently performed by draw control, that is, control that sets and maintains the feed speed of the feeder. In the example of the first embodiment, after the speed adaptation step in the immersion treatment zone Z41 is achieved, the current feed speeds NV21 = V1, NV31 = V2, NV41 = V3, and NV51 = V4 are maintained. Then, a continuous treatment process may be performed. Alternatively, after the speed adaptation step in the immersion treatment zone Z41 is achieved, the speed is adjusted to a speed suitable for performing the continuous treatment step as necessary. NV21 = V1, NV31 = V2, NV41 = V3, NV51 = V4 May perform continuous processing steps at different rates.

  In the continuous processing step, the dancer roller device can be in a state in which the shaft member is fixed without swinging. Fixing the shaft member is advantageous for maintaining steady conditions in the continuous processing step. However, if necessary, it may be used as a state where the shaft member is supported so as to be slidable, similarly to the state in the start-up process.

[2.3. (Falling process)
In the falling step after the continuous processing step, the material film is discharged from the processing path. The falling step includes a connection step (B) and a speed adaptation step (B). In the following, referring again to FIGS. 1 to 7, the lowering process will be described with reference to the example of the lowering process following the example of the starting process and the continuous processing process described above.

[2.3.1. Connection step (B)]
The connecting step (B) is a step of connecting a terminal portion of the material film with a starting end portion of a long tailor film to form a series of falling films. The connecting step (B) may be performed at any stage prior to the speed adaptation step (B).

  For example, the material film 104 upstream from the inlet 111 may be cut during the continuous processing step, and the tail end of the tailor film may be connected to the resulting end. When carrying out such a connecting step (B) involving cutting of the material film 104, an accumulator (not shown) is used upstream of the inlet 111 as necessary, and the conveying speed of the material film 104 in the processing path is as required. Thus, the connecting step (B) can be smoothly performed while maintaining the conveyance speed in the continuous processing step. The apparatus for performing the connection step (B) while maintaining the conveyance speed is not limited to an accumulator, and other apparatuses may be employed. For example, using a web butt-joining apparatus as disclosed in JP-A-6-171806, the operation is performed while maintaining the conveying speed of the material film 104 in the processing path, thereby conveying in the continuous processing step. The connecting step (B) can be performed smoothly while maintaining the speed.

  Alternatively, a film roll of the material film 104 is prepared in advance with a tailor film connected to the end on the core side, and this is installed in the material film feeding apparatus 101, whereby the connecting step (B) is performed in advance. It may be in a broken state.

  As the tailor film, a film having a low degree of softening by the liquid in the tank can be adopted as in the case of the leader film. By using such a tailor film, the tailor film can be advantageously used as a leader film in restarting.

[2.3.2. Speed adaptation process (B)]
The speed adaptation step (B) conveys the falling film, adapts the tailor film to reach the immersion path, and increases the tension of the falling film in the immersion treatment zone, and feeds downstream to the upstream feeding device. This is a step of reducing the relative feed rate of the apparatus.

  As a more specific example, when the continuous processing step shown in FIG. 7 is performed at a feed rate of NV21 = V1, NV31 = V2, NV41 = V3, NV51 = V4, the subsequent speed adaptation step (B) Examples are described below.

[2.3.3. Speed adaptation process in the immersion treatment zone Z21 (B)]
After the connecting portion between the material film 104 and the tailor film in the falling film reaches the immersion path start position SP21, when the falling film is further conveyed in the direction of the arrow A1, the connecting portion moves in the immersion path Z22 and is immersed. In the path Z22, the length occupied by the material film 104 decreases. The tailor film that enters the immersion path Z22 following the material film 104 is not softened by the liquid in the tank 121 in the immersion path Z22, and therefore the length thereof does not extend. Therefore, the tension of the falling film in the immersion treatment zone Z21 increases. This is adapted to reduce the relative feed rate of the downstream feed device relative to the upstream feed device. By such an operation, the speed adaptation step (B) in the immersion treatment zone Z21 is achieved.

  More specifically, the length occupied by the material film 104 in the immersion path Z22 continues to decrease until the connecting portion of the falling film moves from the immersion path start position SP21 to the immersion path end position SP22. Due to such a decrease, a decrease in tension due to the extension of the material film 104 is reduced, and as a result, the tension of the falling film in the immersion treatment zone Z21 is gradually increased. Failure to adapt to such a gradual increase in tension will cause problems such as breakage of the material film 104 and it will be difficult to easily guide the tailor film to the outlet, so an adaptation to such gradual increase is required.

  Therefore, in order to adapt to such gradual increase, the feed speed NV21 of the nip roll N21 remains unchanged while the connecting portion moves from the immersion path start position SP21 to the immersion path end position SP22, while the nip roll downstream of the nip roll N21 is unchanged. That is, the feed speeds NV31, NV41, and NV51 of the nip rolls N31, N41, and N51 are gradually decreased by an amount corresponding to the value of (V2-V1). Due to the gradual decrease, when the connecting portion moves to the immersion path end position SP22, NV21, NV31, NV41, and NV51 are changed to NV21 = V1, NV31 = V2- (V2-V1) = V1, NV41 = V3- (V2- V1) and NV51 = V4- (V2-V1). This achieves a decrease in the relative feed rate that is adapted to the increase in tension in the immersion treatment zone Z21.

  Until the connecting portion passes the end position SP22 of the immersion path Z22 and reaches the start position SP31 of the immersion path Z32, the conveyance of the falling film is not accompanied by the change of the feeding speed, and NV21 = V1, NV31 = V1, This can be performed while maintaining the state of NV41 = V3- (V2-V1) and NV51 = V4- (V2-V1). Further, regarding the feeding speeds NV21 and NV31 of the nip rolls N21 and N31, the states of the speeds NV21 = V1 and NV31 = V1 can be maintained even after the connecting portion passes the start position SP31 of the immersion path Z32.

  However, the tension of the tailor film in the immersion treatment zone Z21 may change according to changes in various conditions. Such a change can be mitigated by a change in the position of the shaft member 128 of the dancer roller device D21 provided at the position DP21. That is, the position change adjusts the path length in the immersion treatment zone by the dancer roller device D21, whereby the tension is adjusted to a higher degree and the falling process can be performed smoothly.

  Further, the change in tension is detected by monitoring the change in position of the shaft member 128 of the dancer roller device D21 or by monitoring the change in tension using another tension measuring device, and accordingly, the nip roll N21 and the corresponding change are detected. The relative feed speed of the downstream nip roll can be adjusted. By such adjustment, it is possible to suppress the change in tension from exceeding the range that can be relaxed by the dancer roller device D21.

[2.3.4. Speed adaptation process in the immersion treatment zone Z31 (B)]
After the connecting portion of the material film 104 and the tailor film in the falling film reaches the immersion path start position SP31, when the falling film is further conveyed in the direction of the arrow A1, the connecting portion moves in the immersion path Z32 and is immersed. In the path Z32, the length occupied by the material film 104 decreases. Therefore, as in the case of the immersion treatment zone Z21, the tension of the falling film in the immersion treatment zone Z31 increases. This is adapted to reduce the relative feed rate of the downstream feed device relative to the upstream feed device. By such an operation, the speed adaptation step (B) in the immersion treatment zone Z31 is achieved.

  More specifically, the length occupied by the material film 104 in the immersion path Z32 continues to decrease until the connecting portion of the falling film moves from the immersion path start position SP31 to the immersion path end position SP32. Due to such a decrease, as in the case of the immersion treatment zone Z21, the tension of the falling film in the immersion treatment zone Z31 gradually increases, and adaptation to such an increase is required.

  Therefore, in order to adapt to such gradual increase, while the connecting portion moves from the immersion path start position SP31 to the immersion path end position SP32, the feed speed NV21 of the nip roll N21 and the feed speed NV31 of the nip roll N31 remain unchanged. The nip rolls downstream of the nip roll N31, that is, the feed speeds NV41 and NV51 of the nip rolls N41 and N51 are gradually reduced by an amount corresponding to the value of (V3-V2). Due to this gradual decrease, when the connecting portion moves to the immersion path end position SP32, NV21, NV31, NV41 and NV51 are changed to NV21 = V1, NV31 = V1, NV41 = V3- (V2-V1)-(V3-V2). = V1, and NV51 = V4- (V2-V1)-(V3-V2) = V4-V3 + V1. This achieves a decrease in relative feed rate that is adapted to the increase in tension in the immersion treatment zone Z31.

  Until the connecting portion passes the end position SP32 of the immersion path Z32 and reaches the start position SP41 of the immersion path Z42, the conveyance of the falling film is not accompanied by a change in the feeding speed, and NV21 = V1, NV31 = V1, This can be performed while maintaining the state of NV41 = V1 and NV51 = V4-V3 + V1. Further, regarding the feed speeds NV21, NV31, and NV41 of the nip rolls N21, N31, and N41, the speeds NV21 = V1, NV31 = V1, and NV41 = V1 are maintained even after the connecting portion passes the start position SP41 of the immersion path Z42. Can be maintained.

  However, the tension of the tailor film in the immersion treatment zone Z31 may change according to changes in various conditions. Such a change can be alleviated by a change in the position of the shaft member 138 of the dancer roller device D31 provided at the position DP31. That is, the position change adjusts the path length in the immersion treatment zone by the dancer roller device D31, whereby the tension is adjusted to a higher degree and the falling process can be performed smoothly.

  In addition, the change in tension is detected by monitoring the change in position of the shaft member 138 of the dancer roller device D31 or by monitoring the change in tension with another tension measuring device, and accordingly, the nip roll N31 and the The relative feed speed of the downstream nip roll can be adjusted. By such adjustment, it is possible to prevent the change in tension from exceeding the range that can be relaxed by the dancer roller device D31.

[2.3.5. Speed adapting step in immersion treatment zone Z41 (B)]
After the connecting portion between the material film 104 and the tailor film in the falling film reaches the immersion path start position SP41, when the falling film is further conveyed in the direction of the arrow A1, the connecting portion moves in the immersion path Z42 and is immersed. In the path Z42, the length occupied by the material film 104 decreases. Accordingly, the tension of the falling film in the immersion treatment zone Z41 increases as in the immersion treatment zones Z21 and Z31. This is adapted to reduce the relative feed rate of the downstream feed device relative to the upstream feed device. By such an operation, the speed adaptation step (B) in the immersion treatment zone Z41 is achieved.

  More specifically, the length occupied by the material film 104 in the immersion path Z42 continues to decrease until the connecting portion of the falling film moves from the immersion path start position SP41 to the immersion path end position SP42. Due to such a decrease, the tension of the falling film in the immersion treatment zone Z41 gradually increases as in the immersion treatment zones Z21 and Z31, and adaptation to such a gradual increase is required.

  Therefore, for adaptation to such gradual increase, the nip roll N21 feed speed NV21, the nip roll N31 feed speed NV31, and the nip roll N41 feed until the connecting portion moves from the immersion path start position SP41 to the immersion path end position SP42. While the speed NV41 is unchanged, the nip roll downstream of the nip roll N41, that is, the feed speed NV51 of the nip roll N51 is gradually decreased by an amount corresponding to the value of (V4-V3). Due to the gradual decrease, when the connecting portion moves to the immersion path end position SP42, NV21, NV31, NV41, and NV51 are changed to NV21 = V1, NV31 = V1, NV41 = V1, and NV51 = V4-V3 + V1- (V4-V3). ) = V1. This achieves a decrease in the relative feed rate adapted to the increase in tension in the immersion treatment zone Z41.

  After the connecting portion passes the end position SP42 of the immersion path Z42, the falling film is conveyed without changing the feed speed, and the states of NV21 = V1, NV31 = V1, NV41 = V1, and NV51 = V1 are maintained. Can be maintained.

  However, the tension of the tailor film in the immersion treatment zone Z41 may change according to changes in various conditions. Such a change can be alleviated by a change in the position of the shaft member 148 of the dancer roller device D41 provided at the position DP41. That is, the position change adjusts the path length in the immersion treatment zone by the dancer roller device D41, whereby the tension is adjusted to a higher degree and the falling process can be performed smoothly.

  Further, the change in tension is detected by monitoring the change in position of the shaft member 148 of the dancer roller device D41 or by monitoring the change in tension with another tension measuring device, and accordingly, the nip roll N41 and the The relative feed speed of the downstream nip roll can be adjusted. By such adjustment, it is possible to suppress the change in tension from exceeding a range that can be relaxed by the dancer roller device D41.

  After the connecting portion has passed the end position SP42 of the immersion path Z42, the material film 104 is all unloaded from the outlet 112 by continuing the conveyance of the falling film, and the entire processing path from the inlet 111 to the outlet 112 is The tailor film occupies the state. At this time, the conveyance of the tailor film in the processing path can be stopped and the falling step can be completed. The tailor film can be used as a leader film in the re-launch. In that case, the lowering step can be a preliminary insertion step in the next starting step.

[2.3.6. Control in speed adaptation process (B)]
In the speed adaptation step (B), the amount of change in the relative feed rate can be determined by detecting the tension applied to the falling film in each immersion treatment zone and according to the detected tension. The tension can be detected by monitoring the change in the position of the shaft member of the dancer roller device, or by monitoring the change in the tension using another tension measuring device, as in the example of the starting process. By using a dancer roller device similar to that used in the start-up process, the same effect as the effect in the start-up process can be obtained.

  Another example of adjusting the amount of change in the relative feed rate is when the relationship between the length of the material film in the immersion path and the degree of change in tension is known and predictable, and the end of the material film After the part reaches the immersion path, it is possible to adjust the relative feed rate in accordance with the degree of progress in the immersion treatment zone of the terminal part. Specifically, the position information of where the connecting portion is located in the processing path is obtained by measurement or calculation, and based on that, the length occupied by the material film in each immersion path is obtained, and the tension corresponding to the length is determined. The degree of increase can be predicted, and the relative feed rate can be adjusted based on the prediction.

  By performing the speed adaptation process (B) described above, it is possible to reduce defects such as breakage of the material film and make the tailor film easier at the fall of the production of a polarizer using a relatively soft material as the material film. Can be directed to the exit. Moreover, the operation from the continuous processing step to the falling step can be easily achieved by an operation without access to the inside of the enclosure and manual operation.

[3. (Modification)
The embodiment of the manufacturing method of the present invention is not limited to the first embodiment described above, and may be an embodiment in which various modifications are added thereto.

  For example, in the first embodiment, in changing the relative feed speed of the downstream feed device with respect to the upstream feed device, the speed of the upstream feed device is not changed and the speed of the downstream feed device is changed. However, the relative feed rate may be changed in other manners. Specifically, an increase in the relative feed rate of the downstream feed device relative to the upstream feed device may be achieved by making the speed of the downstream feed device unchanged and decreasing the speed of the upstream feed device. It can be achieved by making the speed of the side feed device unchanged and increasing the speed of the downstream feed device, or by reducing the speed of the upstream feed device and increasing the speed of the downstream feed device. Good.

  In the first embodiment, the nip roll is used as the feeding device. However, the present invention is not limited to this, and any device that can convey the film while applying tension to the film can be used as the feeding device. For example, a feeding device such as a suction roll can be used.

  In the first embodiment, the tension in the immersion treatment zone is mainly detected by the dancer roller device, but the present invention is not limited to this, and the tension is detected in addition to or in place of the dancer roller device. You may carry out by apparatus other than. For example, the tension may be detected by a tension pickup device provided in the guide roll or other rolls.

  In the first embodiment, the position of the dancer roller device in the immersion treatment zone is behind the immersion path, but the present invention is not limited to this, and may be in front of the immersion path, for example. Moreover, although the number of the roller which each dancer roller apparatus in 1st embodiment is equipped with is one, this invention is not limited to this, One dancer roller apparatus has two rollable rollers. It may have the structure similar to the apparatus generally provided with the above and generally called an accumulator or a reservoir.

  In the first embodiment, the change in the relative feed speed of the nip roll as the feed device is gradually increased or decreased. The change in the relative feeding speed of such a feeding device is not limited to a continuous gradual increase or decrease with a constant increase or decrease, but may be a gradual increase or decrease, depending on the change in the film state. It may be an increase or decrease in which the degree of increase or decrease fluctuates, or it may temporarily turn to decrease upon increase, or temporarily increase upon decrease.

  For example, in the process of increasing the relative feed rate of the feed device, if a decrease in film tension and / or excessive film slack is detected, the increase in relative feed rate may be enhanced. In the process of increasing the relative feeding speed of the feeding device, if an increase in film tension and / or excessive tension in the film is detected, the increase in relative feeding speed is attenuated or reversed. sell. In the process of reducing the relative feed rate of the feeder, if a decrease in film tension and / or excessive film slack is detected, the decrease in relative feed rate is attenuated or reversed. sell. In the process of reducing the relative feed rate of the feed device, if an increase in film tension and / or excessive tension in the film is detected, the decrease in relative feed rate may be enhanced.

[4. Manufacturing method of polarizing plate]
The manufacturing method of the polarizing plate of this invention includes the process of obtaining a polarizer by the manufacturing method of the polarizer of this invention, and the bonding process of bonding a polarizer and a protective film. Specifically, the manufacturing method of the polarizing plate of this invention contains the process of obtaining a polarizer, and the bonding process, and also includes arbitrary processes as needed. More specifically, the manufacturing method of the polarizing plate is as follows: the polarizer is manufactured, the polarizer is dried, the polarizer is inspected, the protective film and / or the adhesive is applied to the polarizer, the polarizer and the protective film Steps such as pasting, curing of the adhesive layer, drying of the pasted product, inspection, and winding can be included.

[5. (Description of material)
The material film used for the production method of the present invention is a film including a layer containing polyvinyl alcohol or a modified product thereof. As polyvinyl alcohol or a modified product thereof, a known material used for manufacturing a polarizer can be adopted. The material film may include any other layer in addition to the layer including polyvinyl alcohol or a modified product thereof. As such an arbitrary layer, a layer that can constitute a polarizer by being subjected to treatment in a treatment path together with a layer containing polyvinyl alcohol or a modified product thereof can be adopted. Specifically, a layer of a thermoplastic resin such as a resin containing an alicyclic structure-containing polymer can be used.

  As the liquid constituting the liquid bath used in the production method of the present invention, a known liquid used for production of a polarizer can be adopted. Specifically, water for washing, a dichroic dye solution for dyeing, a solution for performing stretching in the liquid, a solution for complementary color, and the like can be used. Examples of the dichroic dye solution include an aqueous solution containing iodine and potassium iodide, and an aqueous solution containing potassium iodide and boric acid.

  The material of the leader film and the tailor film used in the production method of the present invention can be any material that is less softened than the material film. Specifically, a material such as a polyester film can be adopted.

DESCRIPTION OF SYMBOLS 10 Processing apparatus 101 Material film delivery apparatus 102 Processing path area | region 103 Intermediate winding apparatus 104 Material film 105 Leader film 106 Connection part 107 Enclosure 108 Exhaust duct 109 Lift 111 Inlet 112 Outlet 121 Tank 122 Upper roll 123 Lower roll 125 Guide roll 127 Rail 128 Shaft member 129 Roller 131 Tank 132 Upper roll 133 Lower roll 135 Guide roll 136 Guide roll 137 Rail 138 Shaft member 139 Roller 141 Tank 142 Upper roll 143 Lower roll 147 Rail 148 Shaft member 149 Roller D21 Dancer roller device D31 Dancer roller device D41 Dancer roller device DP21 Dancer roller device position DP31 Dancer roller device position DP41 Nip roll N31 nip roll N41 nip roll N51 nip roll NP21 nip position NP31 nip position NP41 nip position NP51 nip position NV21 nip roll feed speed NV31 nip roll feed speed NV41 nip roll feed speed SP21 dip path start position SP22 dip Path end position SP31 Immersion path start position SP32 Immersion path end position SP41 Immersion path start position SP42 Immersion path end position Z21 Immersion zone Z22 Immersion path Z31 Immersion zone Z32 Immersion path Z41 Immersion zone Z42 Immersion path

Claims (9)

A start-up step of passing the starting end of a long material film from the entrance to the exit of the processing path, and a continuous transfer of the material film along the processing path after completion of the start-up step A manufacturing method of a polarizer including a processing step,
The material film is a film including a layer containing polyvinyl alcohol or a modified product thereof,
The treatment path includes one or more immersion treatment zones,
The immersion treatment zone includes an immersion path through which the material film passes through a liquid bath,
An upstream feeding device capable of adjusting the feeding speed of the material film carried into the immersion treatment zone, and the material film carried out from the immersion treatment zone, on the upstream side and the downstream side of the immersion treatment zone, respectively. A downstream feeding device capable of adjusting the feeding speed of
The start-up step is adapted to allow the material film to reach the immersion path and to reduce the tension of the material film in the immersion treatment zone, and to feed the downstream-side feeder relative to the upstream-side feeder. A production method comprising a speed adaptation step (A) for increasing the speed.   The manufacturing method according to claim 1, wherein a tension applied to the material film is detected, and the speed adaptation step (A) is performed according to the detected tension.   The manufacturing method of Claim 1 or 2 which performs the detection of the said tension | tensile_strength with the dancer roller apparatus provided in parts other than the said immersion path | route in the said immersion process zone.   The manufacturing method according to claim 3, wherein the speed adaptation step (A) includes adjustment of a path length in the immersion treatment zone by the dancer roller device.   The speed adaptation step (A) is adapted to the degree of progression of the start end portion in the immersion treatment zone after the start end portion of the material film reaches the immersion path, and the downstream feeding device The manufacturing method of any one of Claims 1-4 performed by making a relative feed rate increase. As a process prior to the startup process,
A preliminary insertion step in which a leading end of a long leader film is inserted from the entrance to the exit of the processing path so that the leader film extends from the entrance to the exit of the processing path; and an end of the leader film Connecting step (A) with the starting end of the material film to form a series of rising films
Further including
The manufacturing method according to any one of claims 1 to 5, wherein the startup step includes conveying the startup film. After the continuous processing step, further includes a falling step of discharging the material film from the processing path, the falling step,
A connecting step (B) in which a terminal portion of the material film is connected to a starting end portion of a long tailor film to form a series of falling films; and the trailing film is conveyed, and the tailor film reaches the immersion path. A speed adaptation step (B) adapted to increase the tension of the falling film in the immersion treatment zone and to reduce the relative feeding speed of the downstream feeding apparatus with respect to the upstream feeding apparatus;
The manufacturing method of any one of Claims 1-6 containing these. A method of manufacturing a polarizer, comprising: a continuous processing step of continuously conveying a long material film along a processing path; and a falling step of discharging the material film from the processing path after the continuous processing step. There,
The material film is a film including a layer containing polyvinyl alcohol or a modified product thereof,
The treatment path includes one or more immersion treatment zones,
The immersion treatment zone includes an immersion path through which the material film passes through a liquid bath,
An upstream feeding device capable of adjusting the feeding speed of the material film carried into the immersion treatment zone, and the material film carried out from the immersion treatment zone, on the upstream side and the downstream side of the immersion treatment zone, respectively. A downstream feeding device capable of adjusting the feeding speed of
The falling step is
A connecting step (B) in which a terminal portion of the material film is connected to a starting end portion of a long tailor film to form a series of falling films; and the trailing film is conveyed, and the tailor film reaches the immersion path. A speed adaptation step (B) adapted to increase the tension of the falling film in the immersion treatment zone and to reduce the relative feeding speed of the downstream feeding apparatus with respect to the upstream feeding apparatus;
Manufacturing method. The manufacturing method of a polarizing plate including the process of obtaining a polarizer by the manufacturing method of any one of Claims 1-8, and the bonding process of bonding the said polarizer and a protective film.

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