JP3252467B2 - Water film forming equipment for resin film manufacturing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water film forming apparatus,
In particular, the present invention relates to a water film forming apparatus used in a resin film manufacturing apparatus for manufacturing a resin film by supplying a sheet-like molten resin onto a rotating drum.

[0002]

2. Description of the Related Art As a method for producing a resin film at a high speed, a thin film of water is formed on the surface of a rotating body (for example, a casting drum), and a molten resin is supplied to the surface of the casting drum via the water film. A method for producing is known. In general, an apparatus for performing this type of manufacturing method includes a casting drum, a water film forming unit for forming a water film on the surface of the casting drum, and a sheet-like molten film formed on the casting drum on which the water film is formed. A resin supply unit for extruding the resin and a water film removing unit for removing a water film on the surface of the casting drum are provided.

[0003] In such an apparatus, since a water film is interposed between the resin film and the drum surface, air accompanying the resin film is eliminated, and the generation of microbubbles that are easily formed on the resin film surface is greatly reduced. Can be suppressed.
As a result, it is possible to greatly increase the production speed.

[0004]

In the above-mentioned conventional resin film manufacturing apparatus, the casting drum is cooled and humid air is blown from the water film forming portion. The humid air hits the surface of the casting drum and causes dew condensation, thereby forming a water film on the surface of the casting drum. At this time, it is important to form a uniform water film having a predetermined thickness on the surface of the casting drum. For example, when the thickness of the water film is locally thin, the surface tension of this portion becomes strong, and when the manufactured resin film is separated from the casting drum, the portion is difficult to peel off, which may result in film breakage. is there.

Therefore, when humid air is ejected from the water film forming portion to the surface of the casting drum, it is important that the humid air uniformly contact over a predetermined area of the drum surface. An object of the present invention is to provide a water film forming apparatus of a resin film manufacturing apparatus capable of uniformly applying wet air to a drum surface and forming a water film having a uniform thickness on the drum surface.

[0006]

A water film forming apparatus according to the present invention is provided in a resin film manufacturing apparatus for manufacturing a resin film by supplying a sheet-like molten resin onto a rotating drum. This is an apparatus for forming a film.
And it has a device main body, a humid air blowing means, and a mesh member.

The apparatus main body has a chamber which can be arranged close to the drum surface and opens to the drum surface side. The humid air jetting means is means for jetting humid air into a chamber of the apparatus main body. The mesh member is disposed between the humid air blowing means and the opening of the chamber of the apparatus main body, and is a member for diffusing the humid air into the room.

[0008]

In the water film forming apparatus of the resin film manufacturing apparatus according to the present invention, humid air is blown into the room of the apparatus main body. The humid air moves from the opening of the chamber of the apparatus main body to the drum surface, and a mesh member having a predetermined opening ratio is provided between the ejection means and the opening of the chamber, for example, at the outlet of the chamber. . Therefore, the humid air is temporarily prevented from flowing toward the drum side by the mesh member, and is uniformly diffused in the room in the entire axial direction of the drum and the direction intersecting the same. In this state, the moist air reaches the drum surface through the opening of the mesh member. Therefore, the humid air uniformly contacts the drum surface facing the chamber of the apparatus main body,
A water film having a uniform thickness can be formed.

[0009]

FIG. 1 shows an apparatus for manufacturing a resin film according to an embodiment of the present invention. In the figure, the resin film manufacturing apparatus mainly includes a film manufacturing section 1, a film stretching section 2, and a winding section 3. Film Production Department 1
Are a casting drum 4, a resin supply device 5, a static electricity applying device 6, a water film forming device 7, three humid air generating devices 80 (only one is shown in the figure), and a film feeding device. 8 is provided.

The casting drum 4 is a cylindrical member having a smooth outer peripheral surface, and can be rotated counterclockwise by a driving device (not shown). Further, the casting drum 4 has a built-in cold water pipe for circulating cooling water to cool the inner peripheral surface (not shown). The resin supply device 5 has a base (not shown) which is arranged above the casting drum 4 and extends in parallel with the axis of the casting drum 4. From this die, a sheet-like molten resin 5 a having a constant thickness can be supplied onto the casting drum 4.

The static electricity applying device 6 is disposed on the left side of the resin supply device 5 in the figure, slightly away from the outer peripheral surface of the casting drum 4. The static electricity applying device 6 has a static electricity applying wire 6 a extending parallel to the axis of the casting drum 4. The static electricity applying wire 6a includes
A voltage application device (not shown) is connected, and a high voltage can be applied.

The water film forming device 7 is arranged on the right side of the resin supply device 5 in the figure, and can be moved toward and away from the casting drum 4 by the retracting device 9. Here, FIG.
The details of the water film forming device 7 and the evacuation device 9 will be described with reference to FIGS. The water film forming device 7 includes a water film forming unit 19.
And a water film removing unit 20 provided on the film feeder 8 side of the water film forming unit 19 in a unit shape (FIG. 2). As shown in FIG. 3, the water film forming unit 19 includes a main humid air blowing device 21 and a pair of sub humid air blowing devices 22 and 22. The main moist air blowing device 21 is arranged parallel to the axis of the casting drum 4 and has a longer length than the resin supply device 5 (FIG. 4). Main moist air blowing device 21
Has a main body 24 made of an aluminum material into which a sheath heater 23 is cast. The main body 24 has a chamber 25 facing the casting drum 4, and the chamber 25 extends along the axis of the casting drum 4. The width D of the chamber 25 in the direction orthogonal to the axial direction of the casting drum 4 is 2
It is preferably from 0 to 300 mm, more preferably from 50 to 100 mm.
In this embodiment, the width D is set to 75 mm for the casting drum 4 having a diameter of 1 m.

A pipe 26 for discharging humid air into the chamber 25 is disposed above the chamber 25. The lower half of the pipe 26 projects into the chamber 25, and small holes 26a for jetting wet air are provided in a staggered manner at a predetermined pitch. Further, a flexible tube (not shown) from the humid air generator 80 is connected to one end of the pipe 626. A stainless steel wire mesh member 29 is disposed in the opening of the chamber 25. This wire mesh member has a wire diameter of 0.12 mm, a mesh of 80 mesh, and an aperture ratio of 39.3%. The wire mesh member 29 preferably has a mesh of 30 mesh or more and an opening ratio of 30 to 50%. In addition, the wire netting member 29 may be configured by a resin mesh member or the like.

An edge member 28 made of aluminum is attached to the end of the main body 24 on the casting drum 4 side. The edge member 28 extends in parallel with the axis of the casting drum 4, and the end surface on the casting drum 4 side is inclined corresponding to the surface shape of the casting drum 4. A heat insulating material 27 such as glass fiber is disposed on the upper portion and both side portions of the main body 24.

The pair of sub-humidified air blowing devices 22 are located on the resin supply device 5 side of the main moist air blowing device 21.
It is arranged at both ends of the main moist air blowing device 21 (see FIG. 4). The configuration of each sub-moist air blowing device 22 is as follows.
As shown in FIG. 3, the main humid air blowing device 21 is substantially the same as the main humid air blowing device 21, and a heat insulating material 32 provided on the upper portion of the main body 31 and on the side opposite to the main humid air blowing device 21. And an edge member 33 provided on the casting drum 4 side of the main body 31, a stainless steel wire net 34 provided at an opening of the chamber 30, and a flexible tube (not shown) from the humid air generator 80. And a pipe 35 for jetting wet air. A sheath heater 36 is embedded in the main body 31.

As shown in FIG. 5, the water film removing section 20 includes a nonwoven fabric roll 37, a bearing 38 for rotatably supporting the nonwoven fabric roll 37, and an air cylinder for pressing the nonwoven fabric roll 37 against the surface of the casting drum 4. 39. The nonwoven fabric roll 37 extends parallel to the axis of the casting drum 4 (see FIG. 4). Also,
The upper side of the nonwoven fabric roll 37 is covered by a cover (not shown), and is connected to a flexible tube extending from a vacuum pump 67a (FIG. 1).

As shown in FIG. 6, pedestals 41 are fixed to both ends of the water film forming device 7 in the longitudinal direction. A flange 42 is provided on the casting drum 4 side of the receiving table 41. Further, from the water film forming device 7, a pair of brackets 4
3, 43 project in parallel. Each bracket 43 is provided with a pin hole 43a.

The retracting device 9 is mainly composed of a moving section 9a and a docking device 60 (see FIG. 1; the docking device is not shown). Referring to FIGS. 2 and 6,
The details of the moving unit 9a will be described. The moving unit 9a has a moving block 44 and a moving frame 45 fixed on the moving block 44. Moving block 44
Are a pair of brackets 4 projecting from the water film forming device 7.
It is arranged between 3, 43. And moving block 4
A pair of pins 54, 54 projecting from both ends of the 4 are fitted into corresponding pin holes 43 a, 43 a of the bracket 43, whereby the moving block 44 supports the water film forming device 7. The pins 54, 54 are
4 is configured to be able to move in and out of the moving block 44 by a cylinder (not shown) provided in the moving block 4.

On the side end surface of the moving frame 45, two sets of moving rollers 46 are rotatably provided. The moving roller 46 is arranged on a horizontal guide rail 48 supported by a support frame 47, as shown in FIG. A moving air cylinder 49 is fixed to the support frame 47, and a moving frame 45 is supported on a rod tip 49a. In the moving part 9 a, the moving frame 45 can reciprocate along the guide rail 48 by the moving air cylinder 49.

The docking devices 60 are disposed at both ends of the casting drum 4, and are fixed frames (not shown) for rotatably supporting the casting drum.
Attached to. As shown in FIG. 7, the docking device 60 mainly includes a contact portion 63 and an air cylinder 62 for moving the contact portion 63 up and down. The contact portion 63 is formed in a shape that the flange portion 42 of the water film forming device 7 can contact.

At both ends of the contact portion 63, holding links 70 are rotatably mounted. A clamping roller 71 is rotatably mounted at the tip of each holding link 70, and a holding air cylinder 72 is provided at the other end.
Are connected. With such a docking device 60, the water film forming device 7 can take a retracted position indicated by a dashed line in FIG. 1 and a water film forming position close to the casting drum 4. Here, the cylinder stroke of the lifting / lowering air cylinder 62 is such that when the water film forming device 7 is moved to the retracted position, the lower ends of the moist air blowing devices 21 and 22 are at least 50 mm from the surface of the casting drum 4. The edge members 28 and 33 shown in FIG. 3 are set when they are moved to the water film forming position.
The gap E between the tip of the casting drum 4 and the surface of the casting drum 4 is 1 to
It is set to be 5 mm, preferably 1 to 3 mm. When the gap E exceeds 5 mm, in the operation of forming a water film on the casting drum 4 (described later), the drum 4
The moist air is prevented from reaching the casting drum 4 due to the accompanying airflow of, and a favorable water film forming operation cannot be performed.
The evacuation position is set at one position from the surface of the casting drum 4.
00 mm is desirable. The water film formation position is desirably set to 2 mm in order to form a uniform water film. Also,
The flow rate of the air from the air cylinder 62 is set at a speed at which the water film forming device 7 is moved between the retracted position and the water film forming position by 0.1.
It is adjusted so that it can be set to m / s or more. This moving speed is preferably 0.2 m / s.

Each humid air generator 80 has a closed container 81 as shown in FIG. As shown in FIG. 8, one end of a water supply pipe 82 for supplying water into the closed container 81 is arranged in the closed container 81. The water supply pipe 82 has a heating tank 83 and an electromagnetic valve 84.
The heating tank 83 is provided with a heater 85 for heating the water inside.
have. Further, a temperature sensor (not shown) is attached to the temperature raising tank 83.

An air supply pipe 86 is provided at the bottom of the closed container 81.
Is arranged. The air supply pipe 86 has a control valve 87, and compressed air having a constant pressure can be supplied from a compressed air supply device (not shown) such as a compressor. The air supply pipe 86 has a number of small holes for ejecting compressed air in the closed container 81 (as shown). These small holes are set to have a diameter of 5 mm or less (preferably 3 mm or less). Further, the sealed container 81 has therein a heater 88 for heating water, a temperature sensor 89 for measuring water temperature, and a liquid level sensor 90 for detecting a liquid level. The liquid level sensor 90 is
It is arranged at a height of 300 mm or more from the bottom of the sealed container 81. The upper limit of the height of the liquid level sensor 90 is not particularly limited, but is usually regulated by the height of the closed container 81 which is limited in relation to other devices.

A humid air supply pipe 91 is attached to the upper part of the closed vessel 81. The humid air supply pipe 91 mainly includes a supply pipe main body 92 and a heater 93 for keeping warm. One end of the supply pipe main body 92 is attached to the upper end of the closed container 81, and is open in the closed container 81. The supply pipe main body 92 extends upward from the closed container 81, and is bent so as to have an ascending slope on the way. The other end is connected to the other end of the flexible tube for supplying the humid air to the humid air blowing device. The heater 93 is arranged so as to cover the outer peripheral portion of the supply pipe main body 92, and can be controlled by a temperature sensor (not shown).

The film feeder 8 mainly comprises a suction roll 10 and a pair of guide rolls 11 and 12. The suction roll 10 is arranged near the casting drum 4 and extends in parallel with the axis of the casting drum 4. The suction roll 10 can be rotated clockwise by a driving device (not shown). The suction roll 10 has a large number of suction holes on the roll surface, and is connected to a vacuum pump 13. One set of guide rolls 11 and 12 is arranged on the downstream side of the suction roll 10 and is arranged in parallel with the suction roll 10.

The film stretching section 2 is arranged on the downstream side of the film producing section 1 and has a vertical axis stretching section 14 and a horizontal axis stretching section 15 in this order. The longitudinal stretching section 14 is composed of a number of rolls arranged in parallel, and can apply tension in the transport direction to the resin film F from the film manufacturing section 1 to stretch the resin film F in the longitudinal direction. . The horizontal-axis stretching unit 15 can perform a stretching process in the width direction by gripping both side edges of the resin film F.

The winding section 3 has a winding roll 16. A pair of guide rolls 1 for guiding the resin film F from the film stretching unit 2 to the winding roll 16 is provided between the winding roll 16 and the film stretching unit 2.
7, 18 are arranged. Next, a method for producing a biaxially stretched resin film by the resin film production apparatus will be described.

In the film production section 1, cooling water is supplied to the casting drum 4 and the surface temperature of the drum is set to, for example, 2.
Set to 5 ° C. Then, by a driving device (not shown),
The casting drum 4 is rotated counterclockwise. On the rotating casting drum 4, a resin supply device 5 is provided.
The molten resin 5a in the form of a sheet is extruded from the die. When the molten resin 5a from the die contacts the surface of the casting drum 4, it is cooled and solidified to form a resin film F.
The resin film F is brought into close contact with the surface of the casting drum 4 by the static electricity applying device 6. Here, when a high voltage is applied to the static electricity applying wire 6a, the air near the static electricity applying device 6 is ionized, so that the surface of the casting drum 4 is charged and the resin film F adheres.

The resin film F obtained by the casting drum 4 moves according to the rotation of the casting drum 4, leaves the casting drum 4, and is conveyed to the film feeder 8. In the film feeder 8, the resin film F from the casting drum 4 is
The suction roller 10 comes into close contact with the surface of the suction roll 10 and is sent to the guide roll 11 by driving the suction roll 10.
Then, the resin film F is guided by the guide rolls 11 and 12 and is conveyed to the film stretching section 2. Here, the resin film F is stretched in the vertical axis direction and the horizontal axis direction in the vertical axis stretching section 14 and the horizontal axis stretching section 15, respectively, to become a biaxially stretched resin film. The biaxially stretched resin film is conveyed to the winding unit 3 and is guided by guide rolls 17 and
It is guided by 18 and taken up by the take-up roll 16.

In the above manufacturing process, the resin film F
Starts to form a water film on the surface of the casting drum 4. Next, the operation of forming the water film will be described. First, the moving air cylinder 49 of the evacuation device 9 is operated to move the moving block 44 from the position indicated by the solid line in FIG. 1 to the position indicated by the alternate long and short dash line. In this position, the tips of the edge members 28 and 33 of the moist air blowing devices 21 and 22 of the water film forming device 7 supported by the moving block 44 are separated from the surface of the casting drum 4 by about 100 mm.

In this state, when the air cylinders 62 for lifting and lowering the docking devices 60, 60 disposed at both ends of the casting drum 4 are operated to project their rods, the abutting portions 63 of the docking device 60 become wet. Film forming device 7
In contact with the flange portion 42 of the receiving table 41 of the water film forming apparatus 7. Here, the air cylinder 72 for holding the docking device 60 operates, and the rod protrudes. Thereby, the holding links 70 at both ends of the contact portion 63,
70 are rotated, and the clamping roller 7 at the tip thereof is rotated.
The flange portion 42 of the water film forming apparatus 7 is abutted with the contact portion 63
And firmly connect the two.

As described above, when the docking operation of the docking device 60 and the water film forming device 7 is completed, the main humid air blowing device 21 and the sub humid air blowing device 22,
The supply of humid air from the humid air generator 80 corresponding to 22 is started. Here, the operation of supplying the humid air by the humid air generator 80 will be described first. In the water supply pipe 82 of the humid air generator 80, first, water is stored in the temperature raising tank 83. The water stored in the heating tank 83 is
Heated by the heater 85. When the electromagnetic valve 84 is opened, the water in the heated tank 83 heated in this way is supplied to the water supply pipe 8.
2 and is continuously supplied into the closed container 81. Thus, the water from the water supply pipe 82 is stored in the sealed container 81 up to the level of the liquid level sensor 90. When the water level in the sealed container 81 reaches the level of the liquid level sensor 90, the control valve 84 according to a signal from the liquid level sensor 90.
Is closed, and the supply of water into the closed container 81 is stopped.
Note that the water supplied into the closed container 81 may be ordinary drinking water, but is preferably ion-exchanged water. This is because a small hole (not shown) of the air supply pipe 86 is likely to be clogged by calcium contained in the drinking water or the like.

The water supply pipe 82 stored in the closed container 81
Is heated by the heater 88 to a constant temperature in the range of 81 to 90 ° C. Here, the heater 88
It operates according to the signal from the temperature sensor 89, and maintains the water temperature in the closed container at a constant. When the temperature of the hot water in the closed container 81 is set to a constant temperature, next, compressed air with a constant pressure starts to be supplied into the air supply pipe 86 from a compressed air supply device (not shown). In addition, the supply amount of the compressed air is as follows.
It is preferably set to 7 to 30 l / min in the range of 5 to 5 kgf / cm ² . This compressed air is supplied to the control valve 8
When opening 7, a small hole (not shown) spouts into warm water. The ejected air rises in the warm water to absorb moisture, and is stored in the upper portion of the closed container 81 as humid air. Here, as described above, since the diameter of the small hole of the air supply pipe 86 is set in the above-described range, the air from the air supply pipe 86 becomes fine bubbles and rises in the hot water. Further, since the depth of the hot water is set in the above range, the residence time of the air in the hot water is sufficiently ensured. Further, the air in the hot water absorbs moisture efficiently because the water temperature is set in the above-mentioned temperature range. For this reason, the air from the air supply pipe 86 is stored in the upper part of the closed container 81 as stable and stable humid air.

The humid air stored in the upper portion of the closed container 81 is supplied to a corresponding humid air blowing device through a humid air supply pipe 91. Here, the humid air rises inside the supply pipe main body 92 and is supplied to the humid air blowing device via the flexible tube. The moist air in the supply pipe main body 92 is kept warm by the heater 93. Therefore, the humid air is prevented from being condensed in the supply pipe main body 92.
Even if the water is condensed in the supply pipe main body 92, the condensed water is removed from the closed vessel 81 because the supply pipe main body 92 has a rising slope.
Return inside. As a result, moist air having a constant water content can be stably supplied to the water film forming device 7.

When the level of the hot water in the closed vessel 81 decreases and the liquid level drops, the liquid level sensor 90 operates to open the solenoid valve 84, and water is supplied from the water supply pipe 82. The water to be replenished here is previously heated in the temperature raising tank 83 to the temperature of the hot water stored in the closed container 81. In this case, even when new hot water is supplied into the closed container 81, the temperature of the hot water in the closed container 81 does not easily change. As a result, the humid air generator 80 can continuously supply humid air having a constant humidity.

The humid air supplied to the water film forming device 7 is
Main moist air blowing device 21 and sub moist air blowing device 2
It is supplied into the pipes 26 and 35 of 2, 22, and is discharged into the chambers 25 and 30 respectively. Here, the main bodies 24 and 31 of the humid air blowing devices 21 and 22 are connected to the sheath heater 2.
Preheat with 3 and 36. In this case, the humid air is not condensed in the pipes 26 and 35, and
It is discharged into 5,30. The moist air discharged from the pipes 26 and 35 is supplied to the outlet portions of the chambers 25 and 30 by the wire mesh member 2.
Since the cells 9 and 34 are arranged, they can be uniformly diffused into the chambers 25 and 30. Since the water film forming device 7 is sufficiently separated from the surface of the casting drum 4 as described above, the moist air from the moist air blowing devices 21 and 22 does not easily reach the surface of the casting drum 4. For this reason, on the surface of the casting drum 4, dew condensation due to the humid air leaking from the humid air blowing devices 21 and 22 does not easily occur.

Next, when the humid air has sufficiently diffused into the chambers 25, 30 of the main humid air blowing device 21 and the sub humid air blowing devices 22, 22, the water film forming device 7 is shown by a dashed line in FIG. Move from the position to the position indicated by the solid line. Here, in the moving block 44, the pin 54 is moved into the moving block 44 by a pin operation cylinder (not shown), and is extracted from the pin hole 43a of the bracket 43. Thus, the support of the water film forming device 7 by the moving block 44 is released. Next, when the lifting / lowering air cylinder 62 of each docking device 60 is operated to retract the rod, the water film forming device 7 moves away from the moving block 44 and the water film forming position close to the surface of the casting drum 4. Go to At this time, the air cylinder 6
2, the moving speed of the water film forming apparatus 7 is 0.2
m / s, the humid air blowing devices 21 and 22 rapidly approach the surface of the casting drum 4. At this water film forming position, the gap E (FIG. 3) between the lower ends of the edge members 28 and 33 of the moist air blowing devices 21 and 22 and the surface of the casting drum 4 is 2 mm.

In this state, the moist air blowing devices 21 and
The moist air supplied from the second chambers 25 and 30 to the casting drum 4 through the stainless steel wire nets 29 and 34 is cooled by touching the casting drum 4 and dewed to form a water film. At this time, each humid air blowing device 2
Since the gap between the lower ends of the casting drums 1 and 22 and the surface of the casting drum 4 is set to about 2 mm, a uniform water film is formed on the surface of the casting drum 4. Furthermore, when the humid air blowing devices 21 and 22 approach the surface of the casting drum 4, the air cylinder 62 moves the humid air blowing devices 21 and 22 at a moving speed of 0.2 m / s at a high speed. The boundary between the part where the film is not formed and the part where the film is formed can be clarified,
The thickness unevenness of the water film can be suppressed.

Although a water film is continuously formed on the surface of the casting drum 4, the width of the opening of the chamber 25 of the main humid air blowing device 21 is greater than the film length in the axial direction.
In addition, since the distance is set to 75 mm in a direction intersecting with the direction, the moist air can contact the rotating casting drum 4 for a sufficient time, and a more uniform water film can be formed. In addition, at both ends of the water film formed by the main humid air blowing device 21, a sub humid air blowing device 22 is provided.
Are formed one upon another. For this reason, since the water film on the casting drum 4 is prevented from drying at both ends, the thickness of the center portion and both ends is uniform.

The water film disposed on the surface of the casting drum 4 eliminates air flowing into the contact portion with the casting drum 4 accompanying the molten resin 5a from the die. As a result, the adhesion between the resin film F and the casting drum 4 is further improved.
In this case, the resin film F can be produced at a higher speed. In the casting drum 4 after the resin film F has been peeled off,
The water film disposed between the casting drum 4 and the resin film F remains as water droplets. This water drop
It moves to the water film forming device 7 according to the rotation of the casting drum 4 and is removed by the nonwoven fabric roll 37 in the water film forming device 7. Here, the nonwoven fabric roll 37 is rotated by being pressed against the surface of the casting drum 4 by the air cylinder 39 to absorb a water film on the surface of the casting drum 4. The water absorbed by the nonwoven fabric roll 37 is removed by being sucked by the vacuum pump 67a.

On the surface of the casting drum 4 from which water droplets have been removed by the nonwoven fabric roll 37, a water film is formed again by the moist air blowing devices 21 and 22. At this time, since the water film has been removed by the nonwoven fabric roll 37 as described above, a uniform water film with small thickness unevenness can be formed.
For this reason, in the film manufacturing part 1, since the adhesiveness between the resin film F and the casting drum 4 can be maintained well, film breakage due to uneven peeling of the resin film F hardly occurs, and the resin film F can be continuously produced at high speed.

[0042]

As described above, in the present invention, the mesh member is provided at the outlet of the humid air, and the humid air is sufficiently diffused once in the room, so that a uniform water film can be formed on the drum surface. In addition, the peeling performance when the film separates from the drum can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic front view of a resin film manufacturing apparatus employing one embodiment of the present invention.

FIG. 2 is a front view of a retracting device portion of the resin film manufacturing apparatus.

FIG. 3 is a schematic longitudinal sectional view of a water film forming portion of the embodiment.

FIG. 4 is a schematic plan view of a casting drum portion of the resin film manufacturing apparatus.

FIG. 5 is a schematic view of a water film removing section of the embodiment.

FIG. 6 is a perspective partial view of a connecting portion between the evacuation device and the water film forming unit.

FIG. 7 is a schematic view of a docking device portion of the evacuation device.

FIG. 8 is a schematic configuration diagram of a humid air generator portion of the embodiment.

[Explanation of symbols]

 Reference Signs List 4 casting drum 5 resin supply device 21 main humid air blowing device 22 sub humid air blowing device 24, 31 main body 25, 30 chamber 26, 35 pipe 29, 34 wire mesh member

──────────────────────────────────────────────────続 き Continuation of the front page (72) Kunihiko Onishi, 1-1-1 Sonoyama, Otsu City, Shiga Prefecture Toray Industries, Inc. Shiga Works (56) References JP-A-4-70312 (JP, A) JP-A-Hei JP-A-3-16715 (JP, A) JP-A-3-219928 (JP, A) JP-A-1-241413 (JP, A) JP-A-1-53820 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B29C 41/26 B29C 41/34

Claims (3)

(57) [Claims] 1. A water film forming apparatus for forming a water film on a surface of a drum in a resin film manufacturing apparatus for manufacturing a resin film by supplying a sheet-like molten resin onto a rotating drum, An apparatus main body having a chamber that can be disposed close to the drum surface and that opens to the drum surface side; moist air jetting means for jetting moist air into the chamber of the apparatus main body; and the moist air jetting means And a mesh member disposed between the opening of the chamber of the apparatus main body and diffusing humid air into the room, and a water film forming apparatus for a resin film manufacturing apparatus, comprising: (2) The mesh member has a mesh of 30 mesh
The aperture ratio is 30 to 50%.
5. A water film forming apparatus of the resin film manufacturing apparatus according to 4. (3) The said mesh member is a product made from resin.
Water film forming apparatus of the resin film manufacturing apparatus according to 1 or 2
Place.