KR20120012762A - Flexible device and solution film formation method - Google Patents

Abstract

The flexible apparatus 15 of the solution film-forming installation 10 is equipped with the band 30 and the 1st upstream air supply / exhaust unit 41. FIG. The band 30 is an endless flexible support formed in an annular shape. The first upstream air supply / exhaust unit 41 has an air supply unit 61 and a pair of wind shield plates 62. The air supply part 61 has an air supply duct 66. The air supply duct 66 has a plurality of nozzles 67 on the bottom face of the band 30. The air supply unit 61 injects gas from the plurality of nozzles 67 in a direction perpendicular to the membrane surface of the flexible membrane 36. Each wind shield plate 62 is disposed on the passage line at the side edge of the flexible membrane 36 or in the width direction inside the passage line.

Description

CASTING APPARATUS AND SOLUTION FILM-FORMING METHOD

This invention relates to the casting | flow_spread apparatus for forming the film used as retardation film from dope, and a solution film forming method.

A retardation film is used for a liquid crystal display, and with the large screen and high definition of a liquid crystal display, the required quality with respect to retardation film is also becoming severe. What is considered as the required quality is optical characteristics, and optical characteristics include Re, Rth, uniformity of the direction of the slow axis (orientation angle), and the like. Among them, the demand for uniformity in the direction of the slow axis is very strict. Specifically, in the width direction in a long film, restraining in the range of -1.5 degrees or more and 1.5 degrees with respect to the direction of the slow axis for the purpose of the displacement amount of a slow axis (henceforth an axial shift amount), and also It is required to suppress the amount of axial shift in the range of -1 ° or more and 1 ° or less, preferably -0.4 ° or more and 0.4 ° or less in the whole film. In addition, Re is optically anisotropy in a film plane, and Rth is optically anisotropy in a film plane and a film thickness direction. For long films obtained by continuous film production, when nx is the refractive index in the longitudinal direction of the film, ny is the refractive index in the width direction of the film, nz is the refractive index in the thickness direction of the film, and d is the film thickness. Each is obtained by the following formula.

Re = (ny-nx) × d

Rth = ((ny + nx) / 2-nz) × d

As a method of manufacturing the film used as a retardation film, it can be said that the solution film forming method is preferable from a viewpoint of the above optical characteristics. The market of retardation film is expanding, and it is necessary to improve the manufacturing efficiency of the film in solution film production with this market expansion.

The solution film forming method is industrially performed by the continuous method. That is, the casting | flow_spread process until dope is made into flexible film, and a flexible film is peeled off, and the drying process of drying the film which is a peeled flexible film is performed continuously. Increasing the speed in the casting process during the casting process and the drying process leads to an improvement in manufacturing efficiency.

Accordingly, in order to increase the drying speed of the flexible membrane, conventionally, air was blown as in Japanese Patent Laid-Open No. 61-110520 or Japanese Patent Laid-Open No. 64-055214. In Japanese Patent Laid-Open No. 61-110520, dry air was flowed in parallel to the flexible membrane, and the dry air was flowed so as to be a counter flow or a pure wind with respect to the running direction of the flexible membrane. In addition, Japanese Patent Laid-Open No. 64-055214 sprays dry air perpendicularly to the flexible membrane with respect to the flexible membrane formed with a specific dope on the traveling support.

In addition, Japanese Patent Laid-Open No. 64-055214 sprays wind on the flexible membrane for drying, and sets the angle between the direction of the wind and the surface of the support to 45 ° to 80 ° or 90 °. In Japanese Patent Laid-Open No. 2003-103544, the direction of the wind from the nozzle toward the casting membrane is set to 45 ° to 90 °.

By the way, in the method of drying a casting film | membrane by making it wind, in order to advance the drying effectively and efficiently, the air sprayed as wind is heated and warmed. In this way, when the heated air is brought into contact with the flexible membrane, the exposed portion of the support, on which the flexible membrane is not formed, is gradually heated up. If the temperature of the exposed part of the support becomes too high and the temperature rises too much, the temperature of each side of the flexible film is too high to foam.

Therefore, in order to prevent the temperature rise of the exposed part of the support side by the wind sprayed on the flexible membrane, Japanese Patent Laid-Open No. 2005-047141 is provided with a wind shield plate to prevent the wind from reaching the exposed part of the support.

However, the method of injecting wind in parallel to the flexible membrane has a problem that a fine line extending in the flexible direction occurs in the flexible membrane, although the drying speed is faster than that of the non-wind sprayed. In addition, Japanese Patent Laid-Open No. 2003-103544 sprays wind vertically to the flexible membrane and winds it toward the upstream side after it reaches the flexible membrane. It is pointed out that this flow makes film thickness nonuniform.

Here, in Japanese Patent Application Laid-Open No. 2003-103544, the temperature of the gas to be injected is raised to further increase the drying speed. However, if the temperature of the substrate is raised in this manner, the temperature of the support becomes uneven in the width direction during repeated casting and peeling, so that the optical properties of the film obtained, especially, the amount of axial deviation is large and uneven in the width direction, or The side part may be bent. Once the support starts to bend, the deflection gradually increases as the vehicle continues to run, and correction during driving is almost impossible. In addition, in recent years, there has also been a demand for widening of the film, and the above-mentioned problem becomes more remarkable in the widening of the support for widening of the support due to the widening of the film and for the further enhancement of the production efficiency. Further, in Japanese Laid-Open Patent Publication No. 2005-047141, gas flows in parallel between one pair of wind shield plates and the other with respect to the flexible membrane, so that the temperature of the gas in the width direction of the flexible membrane becomes nonuniform. Since the temperature of a base | substrate becomes nonuniform in the width direction of a flexible film | membrane, there exists a problem that an axial shift amount becomes nonuniform especially in the width direction among the optical characteristics of a film.

Accordingly, in view of the above problems, the present invention aims to homogenize in the width direction of the slow axis of the film while improving the new drying speed of the flexible film in order to increase the production efficiency of the film by solution film formation, and to warp the support. An object of the present invention is to propose a casting apparatus and a solution film forming method for preventing the same.

In order to solve the said subject, the flexible apparatus of this invention is equipped with a flexible support body, a 1st air supply part, and a pair of 1st wind block member. The flexible support is annular. The flexible support has a flexible film formed on the flexible surface on which the dope is flexible. The flexible support continuously circulates in the longitudinal direction to return from the peeling position to the flexible position. The peeling position is a position at which the flexible film is peeled off. The flexible position is a position at which the dope is flexible. The first air supply unit emits heated gas. The first air supply unit emits the gas from an opening opposite the flexible support. The first air supply unit emits the gas in a direction perpendicular to the membrane surface of the flexible membrane. The pair of first wind blocking members extend along the running path of the flexible support. The first wind block member is disposed on the passage line at the side edge of the flexible membrane or inside the width direction of the flexible support than the passage line. The first wind block member suppresses the outflow of the gas from the vicinity of the membrane surface of the flexible membrane to the exposed portion of the side of the flexible support.

Preferably, the first air supply unit has an air supply duct and a plurality of nozzles. A bottom surface of the air supply duct is disposed to face the flexible support so as to cover the flexible membrane passing therethrough. The nozzle protrudes from the bottom surface of the air supply duct. The plurality of nozzles are arranged at intervals in the running direction of the flexible support. The opening is provided at the tip of the nozzle. The opening has a slit shape extending in the width direction of the flexible support. The said wind block member is provided in the position from which the height from the said flexible surface becomes lower than the said air supply duct.

It is preferable that a flexible apparatus further has an exhaust part. The exhaust portion sucks the atmosphere around the flexible membrane from the plurality of openings. The exhaust part is provided at a position higher than the wind blocking member. The plurality of openings of the exhaust portion are provided to face each other between the nozzle and the nozzle.

It is preferable that a flexible apparatus is provided with a 2nd air supply part and a 2nd wind shield member. The second air supply unit emits heated gas. The second air supply unit is provided to face the first air supply unit with the flexible support interposed therebetween. The second air supply unit emits the gas from an opening opposite the flexible support. The second air supply unit emits the gas in a direction perpendicular to the flexible support. The second wind block member extends along the running path of the flexible support. The second wind block member is provided to face the first wind block member with the flexible support interposed therebetween. The second wind block member suppresses the outflow of the gas from the second air supply portion to a side corresponding to the exposed portion of the non-flexible surface. The non-flexible surface is a surface opposite to the flexible surface.

The flexible device preferably includes a third air supply unit downstream of the first air supply unit. The first air supply unit is installed in a first travel region in which the flexible support travels with the flexible surface facing upward. The third air supply portion has an opening toward the upstream side in the running direction of the flexible support. The third air supply unit sends a gas, which becomes a counter flow parallel to the membrane surface of the flexible membrane passing through the opening.

It is preferable that the said 3rd air supply part is provided in the 2nd travel area which the said flexible support body drives with the said flexible surface facing down.

The solution film forming method of the present invention includes a flexible film forming step (A step), a drying step (B step) after peeling, a drying step (C step) before peeling, and a suppression step (D step). A-step casts dope to the annular casting support which runs continuously in a longitudinal direction, and forms a casting film. Step B peels the flexible film from the flexible support and dries. The said A step is performed again with respect to the said flexible support body after peeling the said flexible film. Step C injects gas in a direction perpendicular to the membrane surface of the flexible membrane to dry the flexible membrane. D step is performed during the said C step. D-step suppresses the outflow of the said gas from the vicinity of the film surface of the said flexible film to the exposed part of the side part of the said flexible support body by a pair of 1st wind shielding member. The pair of first wind blocking members are disposed on the passage line at the side edge of the flexible membrane or inside the width direction of the flexible support than the passage line. The first wind block member extends along the running path of the flexible support.

It is preferable to let the said gas out from the said opening of the 1st air supply part which has a some nozzle in which an opening is formed in an air supply duct and a front-end | tip. A bottom surface of the air supply duct is disposed to face the flexible support so as to cover the flexible membrane passing therethrough. The nozzle protrudes from the bottom surface of the air supply duct. The plurality of nozzles are arranged at intervals in the running direction of the flexible support. The opening has a slit shape extending in the width direction of the support. The wind blocking member is provided at a position where the height from the flexible surface is lower than the air supply duct. The flexible surface is a surface on which the dope of the flexible support is cast.

It is preferable to suck the atmosphere around the said flexible film at the position higher than the said 1st wind block member, and opposing between the said nozzle and the angle of the said nozzle.

It is preferable that the solution film forming method further includes the following E steps and F steps. E step injects the heated gas to the said flexible film in which the said gas is injected from the said 1st air supply part, and raises the temperature of the said flexible film. The gas of this E-step is injected in the direction perpendicular to the non-flexible surface. The non-flexible surface is a surface opposite to the flexible surface of the flexible support. The F step suppresses the outflow of the gas to the side corresponding to the exposed portion of the non-flexible surface by the second wind block member. The second wind block member extends along the running path of the flexible support. The second wind block member is provided to face the first wind block member with the flexible support interposed therebetween.

It is preferable that the solution film forming method is provided with the following G steps. The G step is performed after the C step. G-step dries the said flexible film by sending the gas which becomes a counterflow parallel to the said membrane surface. The said C step is performed with respect to the said flexible film on the said flexible support body which runs with the said flexible surface facing up.

It is preferable to perform the said G step with respect to the said flexible film on the said flexible support body which runs with the said flexible surface facing down.

According to the present invention, in order to improve the new drying speed of the flexible film in order to increase the production efficiency of the film by solution film formation, while the slow axis direction in the width direction of the film is made uniform, the amount of axial shift is reduced and the bending of the support can be prevented. have.

The above objects and advantages will be readily understood by those skilled in the art by reading the detailed description of the preferred embodiments with reference to the accompanying drawings.
1 is a schematic view of a solution film production facility.
2 is a schematic side view of the first upstream air supply / exhaust unit.
3 is a plan schematic view of the first upstream air supply / exhaust unit.
4 is a cross-sectional view taken along line IV-IV of FIGS. 3 and 4.
5 is a side schematic view of the second upstream air supply / exhaust unit.

It is preferable to perform 1st Embodiment of this invention by the solution film forming installation 10 shown in FIG. The solution film forming equipment 10 includes a casting device 15, a first tenter 17, a roller drying device 21, a second tenter 23, a slitter 26, and a winding device 27. Is provided in order from the upstream side. The casting apparatus 15 forms a polymer film (hereinafter simply referred to as "film") 12 from the dope 11 in which the polymer is dissolved in the solvent. The 1st tenter 17 advances drying of the film 12, supporting each side of the film 12 with the clip 16 as a support means. The roller drying apparatus 21 dries while supporting the film 12 with the some roller 20. The 2nd tenter 23 supports each side part of the film 12 with the clip 22 as a support means, and provides the tension | tensile_strength with respect to the film 12 in the width direction. The slitter 26 cuts off the support trace of each side supported by the clip 16 of the first tenter 17 and the support means 22 of the second tenter 23. The winding device 27 winds the film 12 around a winding core, and makes it a roll shape.

In addition, in this specification, a solvent content rate (unit;%) is a value of a dry amount reference | standard. Specifically, when the mass of the solvent is x and the mass of the film 12 is y, the solvent content rate (unit;%) is a percentage obtained by {x / (y-x)} × 100.

The flexible device 15 includes a band 30 which is an endless flexible support formed in an annular shape, a first roller 31 and a second roller 32 which rotate in the circumferential direction. The band 30 is wound around the peripheral surfaces of the first roller 31 and the second roller 32. At least any one of the 1st roller 31 and the 2nd roller 32 should just be a drive roller which has a drive means. The band 30 which abuts on a circumferential surface is conveyed by this rotation of this drive roller in a circumferential direction. By this conveyance, the band 30 circulates and runs continuously in a longitudinal direction.

The upper side of the band 30 is provided with a flexible die 35 for flowing out the dope 11. By continuously flowing out the dope 11 from the casting die 35 to the conveyed band 30, the dope 11 is cast on the band 30, and the casting film 36 is formed. In addition, the position where the dope 11 starts contact with the band 30 is called flexible position PC hereafter.

The 1st roller 31 and the 2nd roller 32 are equipped with the temperature controller (not shown) which controls circumferential surface temperature, respectively. The first roller 31 is cooled to have a circumferential surface temperature in a predetermined range. By cooling the first roller 31, the band 30 is cooled every time it changes. Thereby, even if it continues heating by the 1st upstream area | region exhaust / exhaust unit 41, the 1st downstream station air-discharge unit 42, and the 2nd downstream station air-discharge unit 43 mentioned later, the band 30 will continue. The rise in temperature of both side portions 30s (see FIG. 3) of is more surely prevented. The casting die 35 is provided above the band 30 on the first roller 31, and the casting position PC is on the first roller 31. The second roller 32 is heated so that the circumferential surface temperature is in a predetermined range. By heating the second roller 32, the cast film 36 is dried more effectively.

It is preferable to make the peripheral surface temperature of the 1st roller 31 into the range of 3 degreeC or more and 30 degrees C or less, It is more preferable to set it as the range of 5 degreeC or more and 25 degrees C or less, It is set as the range of 8 degreeC or more and 20 degrees C or less. More preferred. It is preferable to make the circumferential surface temperature of the 2nd roller 32 into the range of 20 degreeC or more and 50 degrees C or less, It is more preferable to set it as the range of 25 degreeC or more and 45 degrees C or less, and to set it as the range of 30 degreeC or more and 40 degrees C or less. More preferred.

The flexible die 35 is not limited to an aspect provided above the band 30 on the first roller 31. For example, you may provide above the band 30 toward the 2nd roller 32 from the 1st roller 31. FIG. In this case, the roller 33 is arrange | positioned under the band 30 toward the 2nd roller 32 from the 1st roller 31, and above the band 30 supported by the roller 33 is carried out. It is preferable to arrange the flexible die 35.

The pressure reducing chamber is provided upstream in the traveling direction of the band 30 with respect to the dope 11 which extends from the casting die 35 to the band 30, what is called a bead, but illustration is abbreviate | omitted. This pressure reduction chamber sucks in the atmosphere of the upstream area of the dope 11 which flowed out from the casting die 35, and reduces the said area.

After the flexible film 36 is made hard enough to be conveyed to the 1st tenter 17, it peels off from the band 30 in the state containing a solvent. It is more preferable to perform peeling in the range of 20 mass% or more and 50 mass% or less, More preferably, 25 mass% or more and 45 mass% or less of solvent content rate. By peeling after reaching the low solvent content rate like 50 mass%, the direction of a slow axis can be made uniform more reliably compared with the case where it peels at a solvent content rate larger than 50 mass%. Moreover, when peeling at 20 mass% or more, manufacturing efficiency can be improved more reliably compared with the case where peeling at less than 20 mass%.

At the time of peeling, the film 12 is supported by the peeling roller (henceforth a peeling roller) 37, and the peeling position PP from which the flexible film 36 peels from the band 30 is kept constant. The peeling roller 37 may be a drive roller provided with a drive means and rotating in a circumferential direction. In addition, peeling is performed in the band 30 on the 1st roller 31. FIG. When the band 30 circulates and returns to the flexible position PC from the peeling position PP, the new dope 11 becomes flexible again.

The first travel region in which the flexible surface of the band 30 on which the dope 11 is flexible travels upward in the traveling path of the band 30 includes an upstream region in the flexible film formation region. The flexible film forming region is a region from the flexible position PC to the peeling position PP. In addition, the second travel region in which the band 30 runs with the flexible surface facing downward in the traveling path of the band 30 includes a downstream region of the flexible film formation region.

A first upstream station air supply / exhaust unit 41 is provided below the flexible position PC in the first travel region of the band 30. Downstream of the first upstream station air supply / exhaust unit 41, two downstream station air supply / exhaust units of the first downstream station air supply / discharge unit 42 and the second downstream station air supply / discharge unit 43 are provided. In this manner, the first upstream station air supply / exhaust unit 41, the first downstream station air supply / exhaust unit 42, and the second downstream station air supply / exhaust unit 43 are sequentially formed from the upstream side along the traveling path of the band 30. It is installed. The number of downstream station air supply / exhaust units is not limited to two, but may be one or three or more. The first upstream gas supply / exhaust unit 41 will be described later with reference to other drawings.

The first downstream area air supply / exhaust unit 42 includes an air supply unit 46 through which dry gas is discharged, an exhaust unit 47 that sucks and exhausts gas, and a controller 48. The controller 48 sends a gas to the air supply unit 46, and independently adjusts the temperature, humidity, flow rate from the air supply unit 46, and the suction force in the exhaust unit 47 of the gas. Similarly to the first downstream station supply / exhaust unit, the second downstream station supply / exhaust unit 43 includes an air supply unit 49, an exhaust unit 50, and a controller 51.

The air supply parts 46 and 49 are disposed upstream of the peeling position PP in the second travel area of the band 30. The exhaust portion 47 is disposed upstream of the air supply portion 46 and the exhaust portion 50 is disposed upstream of the air supply portion 49. The outlets 46a and 49a of the air supply parts 46 and 49 through which gas flows out, and the respective suction ports 47a and 50a of the exhaust parts 47 and 50 that suck gas, are both in the width direction of the band 30. It is a slit-shaped opening extended to. The air supply portions 46 and 49 are disposed so that the outlets 46a and 49a face the upstream side in the travel direction of the band 30. The exhaust parts 47 and 50 are disposed so that the suction ports 47a and 50a face the band 30.

By arranging the air supply portions 46 and 49 and the exhaust portions 47 and 50 as described above, the gas from the air supply portions 46 and 49 is conveyed to face the flow parallel to the membrane surface of the flexible membrane 36 passing therethrough. Flows into. By setting it as counterflow, the casting film 36 can be dried more efficiently than pure air.

Since the flexible film 36 is formed on the band surface which faces the band 30 toward the peeling position PP from the 2nd roller 32, support from the downward direction by the support means is impossible. Therefore, the band 30 toward the peeling position PP from the 2nd roller 32 takes the traveling path convex downward by its own weight. In terms of drying efficiency, the gas injection in the vertical direction with respect to the flexible membrane 36 is superior to the case of parallel flow. However, in order to inject gas in the vertical direction at a flow rate such that the drying efficiency can be improved than parallel flow, it is necessary to provide a lot of air supply means below the flexible membrane 36. The more the air supply means is arranged, the higher the possibility that the air supply means and the band 30 come into contact with each other. Therefore, all the air supply parts 46 and 49 are disposed below the band 30 facing the peeling position PP from the second roller 32 to face the peeling position PP from the second roller 32. About the casting film 36, it is made to dry with gas of parallel counterflow.

However, the number of downstream reverse air supply / exhaust units for flowing the gas of the counterflow parallel to the membrane surface of the flexible membrane 36 is not limited to 2 like this embodiment, but may be 1 or 3 or more.

In the present embodiment, the first downstream station air supply / exhaust unit 42 and the second downstream station air supply / exhaust unit 43 are independently controlled by the controller 48 and the controller 51, respectively. You may control independently.

The gas from the air supply parts 46 and 49 is heated by the controllers 48 and 51. By flowing the heated warm air on the casting film 36, the casting film 36 is heated to advance drying.

A blower (not shown) may be disposed in the transport path between the flexible device 15 and the first tenter 17. Drying of the film 12 is advanced by blowing from this blower.

The cast film 36 is peeled off by the peeling roller 37. The exfoliated flexible film 36, that is, the film 12, is guided to the first tenter 17.

The first tenter 17 extends the width of the film 12 by applying the tension in the width direction while supporting the film 12 with the clip 16 and conveying it in the longitudinal direction. The preliminary area, the drawing area, and the relaxation area are formed in the first tenter 17 in order from the upstream side. In addition, there is no need for a relaxation area.

The first tenter 17 has a pair of rails (not shown) and a chain (not shown). Rails are provided on both sides of the conveyance path of the film 12, and a pair of rails are spaced apart at predetermined intervals. This rail spacing is constant in the preheating area, gradually widening towards the downstream in the stretching area, and constant in the relaxation area. Moreover, you may make it become narrow gradually as the rail space | interval of a relaxation area faces downstream.

The chain is mounted so as to be movable along the rail across a prime sprocket and a driven sprocket (not shown). The plurality of clips 16 are attached to the chain at predetermined intervals. The rotation of the prime sprocket causes the clip 16 to circulate along the rail.

The clip 16 starts the support of the film 12 guided near the inlet of the first tenter 17, moves toward the outlet, and releases the support near the outlet. The release of the clip 16 again moves near the entrance to support the newly guided film 12.

The preheating area, the drawing area, and the relaxation area are formed as a space by the delivery of the drying wind from the duct 54 and do not have a clear boundary. The duct 54 is provided above the conveyance path of the film 12. The duct 54 has a slit for sending dry air and is supplied from a blower (not shown). The blower sends the drying air adjusted to a predetermined temperature or humidity to the duct 54. The duct 54 is arrange | positioned so that a slit may face the conveyance path of the film 12. Each slit is a shape extended in the width direction of the film 12, and is formed in a conveyance direction at predetermined intervals from each other. In addition, the duct which has the same structure may be provided below the conveyance path of the film 12, or may be provided both above and below the conveyance path of the film 12. As shown in FIG.

While the film is conveyed in the first tenter 17, the film is dried by the drying wind from the duct 54 and the width can be changed by the clip 16 at a predetermined timing.

It is preferable that the solvent content rate of the film 12 in an extending | stretching area is 7 mass% or more and 30 mass% or less. Elongation rate ER1 (= {(width after extending | stretching) / (width before extending | stretching)) * 100) in an extending | stretching process is more than 5%, and it is preferable that it is 30% or less. It is preferable that the temperature of the film 12 in an extending | stretching process is 80 degreeC or more and 160 degrees C or less.

As for the atmosphere inside the roller drying apparatus 21, temperature, humidity, etc. are adjusted by the air conditioner (not shown). In the roller drying apparatus 21, the film 12 is wound up and conveyed by many rollers 20. As shown in FIG. Also in the roller drying apparatus 21, the solvent evaporates from the film 12. In the roller drying apparatus 21, it is preferable to perform a drying process until a solvent content becomes 5 mass% or less.

In addition, when the film 12 which came out from the roller drying apparatus 21 is curled, you may provide a curl correction apparatus (not shown) between the roller drying apparatus 21 and the 2nd tenter 23. As shown in FIG. The curl straightening device straightens the curl to flatten the film 12.

The second tenter 23 extends the film 12 in the width direction. By this stretching, a film 12 having desired optical characteristics is obtained. The film 12 obtained is used as a retardation film, for example. The second tenter 23 has the same structure as the first tenter 33. Moreover, the duct 55 provided in the 2nd tenter 23 flows toward the film 12 from the slit (not shown), flowing out the dry air heated at predetermined temperature.

Elongation ER2 (= {(width after extending | stretching) / (width before extending | stretching)) * 100) in extending | stretching in the 2nd tenter 23 is more than 10%, and it is preferable that it is 40% or less. It is preferable that the solvent content rate of the film 12 at the time of extending | stretching start is 3 mass% or less. It is preferable that the temperature of the film 12 in extending | stretching is 130 degreeC or more and 200 degrees C or less.

Depending on the optical properties of the film 12 to be manufactured, the second tenter 23 may not be used. For example, when the target characteristic is expressed by the stretching by the first tenter 17, the second tenter 23 may not be used.

The slitter 26 downstream of the second tenter 23 includes a support trace by the clips 16 and 22 of the first tenter 17 or the second tenter 23 when the film 12 is guided. Excision of side The film 12 which cut out the side part is sent to the winding-up apparatus 27, and is wound up in roll shape. In addition, a slitter may be provided between the flexible device 15 and the first tenter 17 or between the first tenter 17 and the roller drying apparatus 21.

The first upstream station air supply / exhaust unit 41 will be described with reference to FIGS. 2 to 4. In addition, illustration of the 1st roller 31 is abbreviate | omitted in FIG. 3, FIG. 4 in order to avoid the trouble of drawing.

The first upstream station air supply / exhaust unit 41 is provided downstream of the flexible position PC, and includes an air supply unit 61, a wind shield plate 62 as a wind shield member, and an exhaust unit 63. The air supply unit 61 injects gas in a direction perpendicular to the membrane surface of the flexible membrane 36 formed on the band 30. As shown in FIG. 3, the length of the slit-shaped dope outlet 35a formed in the flexible die 35 is smaller than the width of the band 30. The flexible film 36 is formed in the center part 30c in the width direction of the band 30 so that the side part 30s of the band 30 may be exposed from this. The wind shield plate 62 suppresses the outflow of gas from the vicinity of the membrane surface of the flexible membrane 36 to the exposed portion of the side of the band 30. The exhaust portion 63 sucks the atmosphere around the flexible film 36. Each of the air supply portion 61, the wind shield plate 62, and the exhaust portion 63 will be described in detail below.

The air supply unit 61 includes an air supply duct 66, a plurality of nozzles 67 provided on the air supply duct 66, a blower 68, and a blower controller 69. The blower 68 delivers gas to the air supply duct 66. The blower controller 69 controls the temperature, humidity, and flow rate of the gas sent from the blower 68 to the air supply duct 66. This control adjusts the flow rate and flow rate of the gas from the nozzle 67. The gas is heated by the blow controller 69. Drying of the casting film 36 is advanced by spraying the heated gas on the casting film 36 as warm air.

The air supply duct 66 is a box-shaped duct whose bottom surface 66a opposes the band 30 so as to cover the flexible film 36 passing therethrough. The plurality of nozzles 67 are arranged so as to be spaced apart in the running direction of the band 30. Each nozzle 67 is elongated in the width direction of the band 30, and the tip is protruded to the bottom surface 66a of the air supply duct 66 toward the band 30, and is installed. An opening 67a is formed at the distal end facing the band 30 to allow gas in the air supply duct 66 to be discharged to the outside. The opening 67a has a long slit shape in the width direction of the band 30.

By sending gas from the opening 67a opposite to the band 30, the gas is sent in a direction perpendicular to the membrane surface of the flexible membrane 36. By injecting the gas in the vertical direction, the cast film 36 can be dried more efficiently than the spray in parallel with the film surface. For this reason, the manufacturing efficiency of the film 12 improves. In addition, in order to send gas in a vertical direction, it may not be blowing from the nozzle 67, for example, even if it forms an opening (not shown) in the bottom face 66a of the air supply duct 66, and it is blowing from this opening, do.

In addition, the drying efficiency is increased by spraying gas on the membrane surface in the vertical direction. Thereby, the solvent content rate of the cast film 36 at the time of peeling, ie, the cast film 36 in the peeling position PP, can be lowered more, and it can also be lowered to 50 mass% or less. Thus, as the solvent content rate of the cast film 36 in the peeling position PP is lowered, the direction of the slow axis in the width direction of the film 12 can be made uniform. Specifically, the angle formed with the direction of the target slow axis can be reduced to a range of -1 ° or more and 1 ° or less, and further to -0.4 ° or more and 0.4 ° or less. It is preferable to make the solvent content rate of the cast film 36 in the peeling position PP into 20 mass% or more and 50 mass% or less. By advancing drying so that the solvent content rate of the flexible film 36 in a peeling position PP may be 50 mass% or less, the axial shift | offset | difference amount of a slow axis can be suppressed more reliably in the range of -1 degrees or more and 1 degrees or less. have.

Although the shape of the opening 67a is preferably made into a slit shape, it is not necessarily necessarily a slit. For example, a plurality of circular or rectangular openings (not shown) may be formed in the width direction of the band 30 at the tip of the nozzle 67.

In FIG. 3, FIG. 4, the length of the opening 67a is shown to be shorter than the distance of the pair of wind shield plates 62 provided in both sides. However, the distance of the pair of wind shield plates 62 is formed by forming the opening 67a of the nozzle 67 longer than the distance of the pair of wind shield plates 62 and blocking the outside of the wind shield plate 62. You may use it shorter.

In the present embodiment, a plurality of air supply ducts 66 are arranged along the traveling path of the band 30. However, instead of this aspect, a plurality of nozzles may be provided in the air supply duct by using one air supply duct extending in the running direction of the band 30 so as to reach the second roller 32. In addition, although six nozzles 67 are provided in the individual air supply ducts 66 in this embodiment, the number of the nozzles 67 is not specifically limited.

It is preferable to make the temperature of the gas from the air supply duct 66 into the range of (Tv-20 degreeC) or more (Tv + 100 degreeC) or less, when making the boiling point of the solvent of dope 11 into Tv. By setting it as (Tv-20 degreeC) or more, the drying efficiency of the cast film 36 becomes high more reliably. Moreover, foaming of the cast film 36 can be prevented more reliably by using below (Tv + 100 degreeC). In addition, when the solvent of the dope 11 consists of multiple components, let Tv be the thing with the lowest boiling point among the boiling components of a solvent component.

It is preferable that the speed of the injection of the gas from the nozzle 67, that is, the flow rate, be in a range of 5 m / sec or more and 25 m / sec or less. By setting it as the flow rate of 5 m / sec or more, the drying efficiency of the casting film 36 becomes high more reliably. Moreover, by setting it as the flow rate of 25 m / sec or less, foaming of the flexible film 36 can be prevented more reliably, or the smooth film 12 of a surface can be obtained reliably.

The wind shield plate 62 extends along the path of the band 30. The wind shield plate 62 is disposed in an upright position on the passage line at the side edge of the flexible membrane 36 or inward in the width direction of the band 30 than the passage line. This suppresses the flow of the heated gas from the air supply duct 66 to the exposed portion of the side portion 30s of the band 30 from the vicinity of the membrane surface of the casting film 36. The temperature rise of the side part 30s can be suppressed by suppressing outflow of the heating gas to the side part 30s. For this reason, while the slow axis direction is uniform in the width direction, and the film 12 is uniform in the whole film, the warpage by the temperature rise of the band 30 can be prevented. 3 and 4 show a case where the wind shield plate 62 is disposed inside the band 30 in the width direction of the pass line at the side edge of the flexible film 36.

Instead of the wind shielding plate 62, a block-like one may be used instead of the wind shielding plate 62 to cover an area from the side edge 36e of the flexible film 36 to the side 30s of the band 30 with the bottom surface.

The wind shield plate 62 is provided lower than the air supply duct 66 with the flexible surface 30a of the band 30 as a reference of the height. That is, the height of the edge portion furthest from the band 30 of the wind shield plate 62 is lower than the height of the bottom surface of the air supply duct 66. Therefore, as shown in FIG. 2, the nozzle 67 arrange | positioned at the bottom face 66a of the air supply duct 66 is not covered with the wind shield plate 62 when seen from the side of the band 30, and a wind shield plate Visible between 62 and air supply duct 66; In this way, the space between the nozzle 67 and each of the nozzles 67 passes through a space between the wind shield plate 62 and the air supply duct 66 to the space above or to the side of the wind shield plate 62. Therefore, the space near the membrane surface of the flexible membrane 36 is spatially connected to the space above or to the side of the wind shield plate 62, whereby the gas from the air supply duct 66 causes the flexible membrane 36 and the wind shield plate to be spaced apart. When it contacts the inner wall of 62, it is guide | induced to the upper side or the side of the wind shield plate 62.

The space fitted to the pair of wind shield plates 62 disposed near both edges 36e of the flexible membrane 36 is supplied by the air supply from the air supply duct 66 than the outer space on the side of the flexible shield 36. The pressure is high. As described above, the space near the membrane surface of the flexible membrane 36 and the external space above or to the side of the wind shield plate 62 are spatially connected. As a result, the atmosphere around the flexible membrane 36 is rapidly replaced by the gas newly flowing out of the air supply duct 66, so that the drying of the flexible membrane 36 proceeds more efficiently.

The wind shield plate 62 is preferably disposed such that the distance D1 with the band 30 is in a range of 10 mm or more and 50 mm or less, more preferably in a range of 10 mm or more and 40 mm or less. By setting D1 to 10 mm or more, contact between the wind shield plate 62 and the band 30 can be more reliably prevented. By setting D1 to 50 mm or less, the outflow of gas from the vicinity of the membrane surface of the casting film 36 to the side portion 30s of the band 30 is more surely suppressed than when it is larger than 50 mm.

The wind shield plate 62 is preferably disposed on the passage line of the side edge 36e of the flexible membrane 36 or above between the passage line and the line 50 mm inside the passage line. That is, it is preferable that the distance D2 of the outer surface of the wind shield plate 62 and the passage line of the side edge 36e of the flexible membrane 36 shall be 0 mm or more and 50 mm or less. By setting it on the passing line (D2 = 0 mm) or the inner side (D2> 0 mm), outflow of gas from the vicinity of the membrane surface of the flexible membrane 36 to the side portion 30s of the band 30 can be more surely suppressed. When D2 is larger than 50 mm, the width of the side portion where the optical characteristics of the film 12, in particular, the direction of the slow axis is different from the target direction becomes larger than that of 50 mm or less, and the width to be excised with the slitter 26 is increased. Sometimes you need to make it louder.

The exhaust unit 63 has a suction duct 72, a suction unit 73, and an exhaust controller 74. The aspirator 73 sucks gas. The exhaust controller 74 controls the suction force in the suction unit 73. By this control, the suction force of the gas from the opening 72a formed in the suction duct 72 is adjusted. The gas is cleaned and exhausted by the exhaust controller 74. In addition, the purified exhaust gas may be sent to the blower 68 to be used for the air supply from the air supply duct 66.

The plurality of suction ducts 72 are installed at a position higher than the wind shield plate 62. Each opening 72a of each suction nozzle opposes between the nozzle 67 and the nozzle 67. In this way, the opening 67a is disposed between the space near the membrane surface of the flexible membrane 36 to be spatially connected and the outer space above or to the side of the wind shield plate 62. For this reason, the atmosphere around the flexible film 36 is guided upward of the wind shield plate 62 more quickly. As a result, the atmosphere around the flexible membrane 36 is transferred to the new gas from the air supply duct 66 more quickly, and the drying of the flexible membrane 36 proceeds more efficiently. In addition, since the suction duct 72 is provided at a position higher than the wind shield plate 62, the outflow of gas from the vicinity of the membrane surface of the flexible membrane 36 to the exposed portion of the side portion 30s of the band 30 is more surely suppressed. . For this reason, while temperature rise of the side part 30s is prevented more reliably, uniformity of the slow-axis direction in the width direction of the film 12 can be aimed at more reliably.

In addition, the suction duct 72 should just be arrange | positioned so that it may become a position higher than the wind shielding plate 62 in the normal direction of the surface of the band 30. As shown in FIG. For example, like the present embodiment, the suction duct 72 may be disposed such that the lower end of the opening 72a is lower than the bottom face 66a of the air supply duct 66, or the bottom surface of the suction duct 72 is supplied with air. The lower end of the opening 72a may be higher than the bottom 66a of the air supply duct 66 at the same height as the bottom 66a of the duct 66. In addition, the suction duct 72 should just be arrange | positioned so that the opening 72a may be located between the nozzle 67 and the nozzle 67 in the travel direction of the band 30. As shown in FIG.

It is preferable that the 1st upstream area | air supply and exhaust unit 41 further includes the air supply part 77 upstream of the air supply part 61, ie, between the flexible position PC and the air supply part 61. As shown in FIG. The air supply unit 77 has a nozzle 78, a blower 79, and a blower controller 80. The blower 79 sends gas to the nozzle 78. The blower controller 80 controls the temperature, humidity, and flow rate of the gas sent from the blower 79 to the nozzle 78. By this control, the flow rate and flow velocity of the gas from the nozzle 78 are adjusted. The gas is heated by the blower controller 80 and the drying of the cast film 36 is advanced by spraying the heated gas on the cast film 36 as warm air.

The nozzle 78 is disposed so that the opening 78a faces the downstream side in the traveling direction of the band 30. As a result, the gas from the opening 78a flows on the flexible film 36 as pure air with respect to the flexible film 36 passing therethrough. By becoming a pure wind, the influence of the airflow to a bead is suppressed. However, the direction of the opening 78a may be a direction slightly inclined toward the flexible membrane 36, or may not be a parallel flow with respect to the membrane surface of the flexible membrane 36 when the flow of gas becomes the pure air to the flexible membrane 36.

The gas from the nozzle 78 flows between the bottom face 66a of the air supply duct 66 and the casting film 36, most of which is sucked into one of the most upstream side of the suction duct 72. As shown in FIG. Thus, by providing the air supply portion 77 and drying the cast film 36 immediately after formation, the drying efficiency of the cast film 36 is further improved, and the manufacturing efficiency of the film 12 is further increased.

As described above, in the present invention, the first flexible film drying step and the second flexible film drying step are performed until the flexible film 36 is peeled off from the band 30. The first flexible membrane drying step is a step of drying the flexible membrane by injecting gas in a direction perpendicular to the flexible membrane by the first upstream air supply / exhaust unit 41. The 2nd flexible membrane drying process sends the gas which becomes a counterflow parallel to a membrane surface by the 1st, 2nd downstream downstream supply / exhaust units 42 and 43 with respect to the flexible membrane 36 after having passed through the 1st flexible membrane drying process. It is a process of advancing the casting film 36.

The central portion 30c of the band 30 on which the cast film 36 is formed is hard to rise in temperature due to latent heat of evaporation of the solvent from the cast film 36. Therefore, in order to further improve the drying efficiency of the cast film 36, the following 2nd Embodiment is preferable.

In the second embodiment of the present invention, the second upstream station air supply / exhaust unit 90 is further provided in the flexible device 15. The second upstream station air supply / exhaust unit 90 is installed downstream of the flexible position PC and is disposed opposite the first upstream station air supply / exhaust unit 41 with the band 30 interposed therebetween.

The second upstream station air supply / exhaust unit 90 includes an air supply unit 91, a wind blocker 92 as a wind blocking member, and an exhaust unit (not shown) similarly to the first upstream station air supply / exhaust unit 41. . Each configuration of the air supply unit 91, the wind shield plate 92 as the wind block member, and the exhaust unit includes the air supply unit 61, the wind block plate 62, and the exhaust unit 63 of the first upstream air supply / exhaust unit 41. Since it is basically the same as), only a point different from these is demonstrated below.

The air supply part 91 injects gas in the vertical direction with respect to the non-flexible surface 30b on the opposite side to the flexible surface 30a of the band 30. The wind baffle plate 92 faces the wind baffle plate 62 with the band 30 therebetween and is installed in an upright position. This wind shield plate 92 suppresses the outflow of the gas from the nozzle 93 of the air supply portion 91 to the non-flexible surface 30b of the side portion 30s. The non-flexible surface 30b of the side part 30s corresponds to the flexible surface 30a of the side part 30s, and is an area | region corresponding to the back side of the flexible surface 30a of the side part 30s.

The wind shield plate 92 is disposed such that the distance D3 between the non-flexible surface 30b is in a range of 10 mm or more and 50 mm or less, similarly to the distance D1 between the wind shield plate 62 and the flexible surface 30a. It is preferable to arrange | position so that it may become in the range of 10 mm or more and 40 mm or less.

The some nozzle 93 is provided in the opposing surface which opposes the non-flexible surface 30b of the air supply duct 96. As shown in FIG. The suction duct 97 of the exhaust portion is provided so that the opening faces the nozzle 93 and the nozzle 93 in the running direction of the band 30. This suction duct 97 should just be arrange | positioned so that opening may become lower than the wind shield plate 92 in the normal direction of the non-flexible surface 30b of a band. The exhaust part sucks the atmosphere around the casting film 36 from the opening of the suction duct 97.

In this manner, the center portion 30c of the band 30 in which the flexible membrane 36 is formed can be warmed more reliably by using the second upstream region air supply / exhaust unit 90. For this reason, compared with 1st Embodiment, the drying efficiency of a cast film improves further and the manufacturing efficiency of the film 12 becomes high. In addition, the drying efficiency of the cast film 36 is increased, so that the solvent content at the peeling position PP is further lowered, and the axial shift amount of the slow axis is more reliably -1 ° or more and 1 ° or less, more preferably -0.4 ° or more. It is suppressed small to the range of 0.4 degrees or less. Moreover, also in this embodiment, since the heating from the non-flexible surface of the side part 30s is suppressed by the wind shield plate 92, the curvature of the band 30 is prevented.

In the present invention, the wider the band 30 is, the more effective it is, and the wider the film is produced, the more effective it is.

This invention is especially preferable when manufacturing the film used as retardation films, such as a liquid crystal display.

The cellulose acylate is not particularly limited. The acyl group of cellulose acylate may be only one type, or may have two or more types of acyl groups. When there are two or more kinds of acyl groups, one of them is preferably an acetyl group. It is preferable that the ratio which esterifies the hydroxyl group of a cellulose with carboxylic acid, ie, the substitution degree of an acyl group, satisfy | fills all following formula (I)-(III). In addition, in the following formula (I)-(III), A and B represent the substitution degree of an acyl group, A is the substitution degree of an acetyl group, and B is a substitution degree of the acyl group of 3-22 carbon atoms.

(I) 2.0≤A + B≤3.0

(II) 1.0≤A≤3.0

(III) 0≤B≤2.0

It is more preferable that the total substitution degree (A + B) of an acyl group is 2.20 or more and 2.90 or less, and it is especially preferable that they are 2.40 or more and 2.88 or less. Moreover, it is more preferable that substitution degree B of the acyl group of C3-C22 is 0.30 or more, and it is especially preferable that it is 0.5 or more. Especially, this invention has a big effect especially when cellulose diacetate (DAC) is used as a cellulose acylate.

Hereinafter, the Example of this invention and the comparative example with respect to this invention are given. Details are described in Example 1, and in other examples and comparative examples, only the conditions different from Example 1 are described.

≪ Example 1 >

The 2nd upstream area | air supply and exhaust unit 90 shown in FIG. 5 was added to the solution film forming facility shown in FIG. 1, and the film 12 for using as a retardation film from the dope 11 was manufactured. The thickness of the target film 12 is 58 micrometers.

The peripheral surface temperature of the 1st roller 31 was 15 degreeC, and the peripheral surface temperature of the 2nd roller 32 was 40 degreeC.

The distance D1 between the wind shield plate 62 and the flexible surface 30a of the band 30 was 10 mm. The distance between the band 30 and the opening 67a of the nozzle 67 was 150 mm. The distance D2 between the outer surface of the wind shield plate 62 and the side edge of the flexible membrane 36 was 0 mm. The temperature of the gas discharged | emitted from the nozzle 67 was 135 degreeC, and the wind speed was 25 m / sec.

In the 1st tenter 17, the film 12 containing a solvent was extended | stretched with 8% widening ratio in the width direction. The film 12 in which the solvent content rate became less than 5 mass% was guided to the second tenter 23. In the 2nd tenter 23, the film 12 was extended so that it might become a 21% widening ratio in the width direction.

In Example 1, foaming was not confirmed in the flexible film 36. In addition, the warpage and deformation of the side portion 30s were not confirmed in the band 30. The solvent content rate in the peeling position PP was 33 mass%. The axial shift | offset | difference amount of the slow axis of the obtained film 12 is suppressed in the range of -0.05 degrees or more and 0.05 degrees or less in the width direction of the film 12, and is -1 degrees or more and 1 degrees or less in the whole region of the film 12. It was suppressed in the range.

<Example 2>

The distance D1 between the wind shield plate 62 and the flexible surface 30a of the band 30 was 40 mm. Other conditions are the same as in Example 1.

In this Example 2, foaming was not confirmed in the flexible film 36. In addition, the warpage and deformation of the side portion 30s were not confirmed in the band 30. The solvent content rate in the peeling position PP was 33 mass%. The axial shift | offset | difference amount of the slow axis of the obtained film 12 is suppressed in the range of -0.05 degrees or more and 0.05 degrees or less in the width direction of the film 12, and is -1 degrees or more and 1 degrees or less in the whole region of the film 12. It was suppressed in the range.

<Example 3>

The distance D2 between the outer surface of the wind shield plate 62 and the side edge 36e of the flexible film 36 was 50 mm. Other conditions are the same as in Example 1.

In Example 3, foaming was not confirmed in the flexible film 36. In addition, the warpage and deformation of the side portion 30s were not confirmed in the band 30. The solvent content rate in the peeling position PP was 33 mass%. The axial shift | offset | difference amount of the slow axis of the obtained film 12 is suppressed in the range of -0.05 degrees or more and 0.05 degrees or less in the width direction of the film 12, and is -1 degrees or more and 1 degrees or less in the whole region of the film 12. It was suppressed in the range.

Comparative Example 1

The wind shield plate 62 and the wind shield plate 92 were not installed. Other conditions are the same as in Example 1.

In this comparative example 1, the side part 30s of the band 30 was bent while repeating casting | flow_spreading and peeling, and the side part 30s did not contact the 1st roller 31. As a result, the temperature of the side part of the casting film 36 became more than the boiling point of a solvent, and the side part foamed. For this reason, the target film 12 could not be manufactured.

Comparative Example 2

The gas was not discharged from the nozzle 67 without operating the blower 68. In addition, the atmosphere was not attracted to the suction duct 72 without operating the aspirator 73. The gas was supplied from the nozzle 78 so as to be a pure air parallel to the casting film. The temperature of the gas supplied from the nozzle 78 was 135 degreeC, and the wind speed was 25 m / sec. The gas to be supplied flows between the pair of wind shield plates 62 to be sucked from the suction port 47a of the exhaust part 47. Other conditions are the same as in Example 1.

In Comparative Example 2, since the gas supplied flows between one and the other of the pair of wind shield plates 62, foaming is not confirmed in the flexible membrane, but the solvent content at the peeling position PP is 60% by mass. The drying efficiency was bad. Moreover, since the temperature in the width direction of the gas which flows between a pair of wind shield plates 62 heats toward the outer side from the inside of the wind shield plate 62, it becomes high as it goes to the side part from the center, and the obtained film axis The amount of shift | deviation increased to -0.5 degrees or more and 0.5 degrees or less in the width direction of a film. Also in the whole area | region of a film, it became large in the range of -2 degrees or more and 2 degrees or less.

Comparative Example 3

The angle of the nozzle 67 was inclined 45 ° with respect to the flexible film so that gas supplied from the nozzle 67 was injected into the flexible film at an angle of 45 °. A part of the gas after being injected flowed so as to be a pure wind in parallel with a casting film. Other conditions are the same as in Example 1.

In Comparative Example 3, since the gas supplied flows between one and the other of the pair of wind shield plates 67, foaming was not confirmed in the flexible membrane, but the solvent content at the peeling position PP was 50% by mass. The drying efficiency was bad. Since the temperature in the width direction of the gas which flows between a pair of wind shielding boards has heat dissipation toward the outer side from the inside of the wind shielding board 67, it becomes high as it goes to the side part from the center, and the amount of axial shift | offset of the obtained film is a film In the width direction of, it grew to -0.2 degrees or more and 0.2 degrees or less. Also in the whole area | region of a film, it became large in the range of -1.6 degrees or more and 1.6 degrees or less.

Claims (12)

Cyclic flexible support;
A first air supply unit for discharging the heated gas; And
A flexible device having a pair of first wind block members extending along a running path of the flexible support, the device comprising:
The flexible support is circulated so that a flexible film is formed on the flexible surface on which the dope is flexible, and continuously runs in the longitudinal direction to return from the peeling position where the flexible film is peeled back to the flexible position on which the dope is flexible,
The first air supply unit discharges the gas from an opening opposite the flexible support and discharges the gas in a direction perpendicular to the membrane surface of the flexible membrane,
The first wind block member is disposed on the passage line at the side edge of the flexible membrane or inward in the width direction of the flexible support from the passage line, and from the vicinity of the membrane surface of the flexible membrane to the exposed portion of the side of the flexible support. Flexible device characterized by suppressing the outflow of the gas. The method of claim 1,
The first air supply unit has an air supply duct and a plurality of nozzles, and the air supply duct has a bottom surface disposed to face the flexible support so as to cover the flexible membrane passing therethrough, and the nozzle protrudes from the bottom surface of the air supply duct. The plurality of nozzles are arranged at intervals in the running direction of the flexible support, the opening is provided at the tip of the nozzle, the opening is a slit shape extending in the width direction of the flexible support, the wind The blocking member is provided at a position where the height from the flexible surface is lower than the air supply duct. The method of claim 2,
An exhaust portion for sucking the atmosphere around the flexible membrane from the plurality of openings,
And the exhaust portion is provided at a position higher than the wind block member, and the plurality of openings are provided to face each other between the nozzle and the angle of the nozzle. The method of claim 2,
A second air supply unit for discharging the heated gas; And
A flexible device, further comprising a second wind block member extending along a running path of the flexible support:
The second air supply unit is provided to face the first air supply unit with the flexible support interposed therebetween, and discharges the gas from an opening facing the flexible support, and discharges the gas in a direction perpendicular to the flexible support,
The second wind block member is disposed to face the first wind block member with the flexible support interposed therebetween, and prevents the outflow of the gas from the second air supply portion to a side corresponding to the exposed portion of the non-flexible surface. Suppress it,
And the non-flexible surface is a surface opposite to the flexible surface. The method of claim 1,
A third air supply unit is provided downstream of the first air supply unit,
The first air supply portion is provided in a first travel region in which the flexible support travels with the flexible surface facing upwards,
And said third air supply portion has an opening toward an upstream side in the running direction of said flexible support, and sends a gas, which is a counter flow parallel to the membrane surface of said flexible membrane, to pass from said opening. The method of claim 5, wherein
And the third air supply portion is provided in a second travel region in which the flexible support travels with the flexible surface facing downward. (A) forming a casting film by casting dope in the annular casting support which runs continuously in a longitudinal direction;
(B) peeling and drying said flexible film from said flexible support;
(C) drying the flexible membrane by injecting gas in a direction perpendicular to the membrane surface of the flexible membrane;
(D) A solution film forming method comprising the step of performing the step C to suppress the outflow of the gas from the vicinity of the film surface of the flexible membrane to the exposed portion of the side of the flexible support by a pair of first wind blocking members:
The step A is again performed on the flexible support after removing the flexible film.
The pair of first wind blocking members are disposed on a passage line at the side edge of the flexible membrane or inside the width direction of the flexible support than the passage line, and the first wind blocking member travels of the flexible support. Solution forming method, characterized in that extending along the furnace. The method of claim 7, wherein
The gas is discharged from the opening of the first air supply unit having the air supply duct and the plurality of nozzles having an opening formed at the front end thereof, and the air supply duct is disposed to face the flexible support passing through the air supply duct; The nozzles protrude from the bottom surface of the air supply duct, the plurality of nozzles are arranged at intervals in the running direction of the flexible support, the opening is a slit shape extending in the width direction of the support, the wind The blocking member is provided at a position where the height from the flexible surface is lower than the air supply duct, and the flexible surface is a surface on which the dope of the flexible support is cast. The method of claim 7, wherein
And the atmosphere around the flexible membrane is sucked at a position higher than the first wind block member and opposed between the nozzle and the angle of the nozzle. The method of claim 8,
(E) injecting a heated gas into the flexible membrane to which the gas is injected from the first air supply unit, and raising the temperature of the flexible membrane;
(F) A solution film forming method further comprising the step of suppressing the outflow of the gas to the side corresponding to the exposed portion of the non-flexible surface by a second wind block member:
The gas is injected in a direction perpendicular to the non-flexible surface, the non-flexible surface is a surface opposite to the flexible surface of the flexible support,
And the second wind blocking member extends along the running path of the flexible support, and is installed to face the first wind blocking member with the flexible support therebetween. The method of claim 7, wherein
(G) further comprising the step of drying the cast film by sending a gas which is carried out after the C step and becomes a counter flow parallel to the membrane surface,
Said C step is performed with respect to the said flexible film on the said flexible support body which runs with the said flexible surface facing upwards, The solution film forming method characterized by the above-mentioned. The method of claim 11,
The said G step is performed with respect to the said flexible film on the said flexible support body which runs with the said flexible surface facing down, The solution film forming method characterized by the above-mentioned.

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