WO2020116071A1

WO2020116071A1 - Apparatus for producing separator film, and method for producing separator film

Info

Publication number: WO2020116071A1
Application number: PCT/JP2019/043317
Authority: WO
Inventors: 佐野　孝義; 政嗣田村; 佳久池田; 充彦齊藤; 大地湯川; 遠矢　良洋; 智則山口; 拓也萩原
Original assignee: 東芝機械株式会社
Priority date: 2018-12-07
Filing date: 2019-11-05
Publication date: 2020-06-11
Also published as: KR102382246B1; KR20210084607A

Abstract

In order to reduce the vertical heat shrinkage of a separator film while suppressing prolonged production time and apparatus configuration complexity, this apparatus comprises: an extractor (108) for extracting a liquid plasticizer from a raw film (5a) in the shape of a porous film by performing vertical-stretching and transverse-stretching on a sheet obtained by melt-kneading a polyolefin-based resin and a liquid plasticizer and then molding the melt-kneaded product; and a vertical shrinkage-type second transverse-stretching machine (110) provided with clip chains (8, 9) having a plurality of clips (18) for gripping the raw film (5a), and capable of vertically shrinking the raw film (5a) by adjusting the distances between the clips (18) while vertically conveying the raw film (5a) and transversely stretching the raw film (5a) by moving the clip chains (8, 9).

Description

Separator film manufacturing apparatus and separator film manufacturing method

The present invention relates to a separator film manufacturing apparatus and a separator film manufacturing method, and more particularly to a separator film manufacturing apparatus and a separator film manufacturing method for manufacturing a separator film used in a lithium ion battery.

Used for battery separators, hemodialysis membranes, breathable films, filters, etc., porous membranes with fine pores are prepared by melt-kneading a polyolefin resin and a liquid plasticizer to cause phase separation, and then finely stretching by stretching. There is known a film forming method in which a hole is stretched and opened. For example, in Patent Document 1, polyethylene powder is heated and melted using oil or liquid paraffin as a solvent, and after phase separation, longitudinal stretching is performed by a longitudinal stretching machine, and then transverse stretching is performed by a transverse stretching machine. A method for forming a porous film is described in which pores are stretched and opened. In addition, the vertical direction here is a direction along the transport direction of the film, and the horizontal direction is a direction orthogonal to the transport direction, that is, the width direction of the film to be transported.

Japanese Patent No. 5366426

Here, in a separator film used in a lithium-ion battery, which is a kind of porous film, a polyolefin resin and a liquid plasticizer are melt-kneaded and phase-separated into a sheet, and longitudinal stretching and transverse stretching are performed. There is known a method in which a film having fine porosity is thereby formed, and then a second transverse stretching is performed through a liquid plasticizer extraction step and a drying step, followed by winding. The purpose of the second transverse stretching is heat setting of the film and adjustment of fine holes. In the second transverse stretching step, the film is stretched in the transverse direction and then contracted in the transverse direction in order to remove the residual stress generated by the stretching. In other words, residual stress causes so-called heat shrinkage, which is shrinkage that occurs in the film after production, and therefore, in the second transverse stretching step, the residual stress in the transverse direction out of the residual stress that causes heat shrinkage is reduced. By removing it, the heat shrinkage in the lateral direction is reduced.

On the other hand, it is difficult to remove the residual stress in the longitudinal direction of the film by the transverse stretching machine because the transverse stretching machine cannot shrink the film in the longitudinal direction. Has become difficult to reduce. Therefore, in the conventional separator film manufacturing method, in order to reduce the residual stress in the longitudinal direction of the film, the exposure time of the film at a high temperature is lengthened, or roll annealing or aging is performed after the second transverse stretching. I am. When lengthening the exposure time at high temperature, the exposure time is lengthened by lengthening the oven length of the transverse stretching machine or slowing down the transport speed of the film. As a result, the residual stress in the longitudinal direction of the film can be reduced although it is insufficient. Roll annealing is a process of passing the film through a plurality of heating rolls to shrink the film and shrink the film in the longitudinal direction. Aging is a process of shrinking a film by winding the film and then leaving it under heat for a predetermined time.

However, the longer the exposure time at high temperature, the longer the manufacturing time. Further, in order to perform roll annealing and aging, equipment for each treatment is required, which may complicate the apparatus configuration for manufacturing the separator film. Therefore, there is room for improvement in the conventional separator film manufacturing apparatus and manufacturing method from the viewpoint of reducing the vertical heat shrinkage rate of the separator film.

The present invention has been made in view of the above, while suppressing the lengthening of the manufacturing time and the complexity of the apparatus configuration, a separator film manufacturing apparatus and a separator film separator that can reduce the vertical heat shrinkage rate of the separator film. It is an object to provide a method for producing a film.

In order to solve the above-mentioned problems and achieve the object, the separator film manufacturing apparatus according to the present invention has a longitudinal stretching and a transverse direction with respect to a sheet obtained by molding a polyolefin resin and a liquid plasticizer after melt-kneading. An extracting device for extracting the liquid plasticizer from a raw film made into a porous film by performing stretching, and a clip chain having a plurality of clips for holding the raw film are provided, and the clip chain is run. A longitudinal shrinkage type heat treatment device capable of contracting the raw film in the longitudinal direction by stretching the raw film in the lateral direction while conveying the raw film in the longitudinal direction, and adjusting the interval between the clips. And

Further, in order to solve the above-mentioned problems and to achieve the object, the method for producing a separator film according to the present invention is a longitudinal direction with respect to a sheet obtained by melt-kneading a polyolefin resin and a liquid plasticizer. A step of extracting the liquid plasticizer from the raw film made into a porous film by performing stretching and transverse stretching, and the raw fabric while conveying the raw film extracted from the liquid plasticizer in the longitudinal direction. Stretching the film in the transverse direction and shrinking the original film in the longitudinal direction.

The separator film manufacturing apparatus and the separator film manufacturing method according to the present invention have an effect that the longitudinal heat shrinkage rate of the separator film can be reduced while suppressing the increase of manufacturing time and the complexity of the apparatus configuration. ..

FIG. 1 is a block diagram showing an apparatus configuration of the separator film manufacturing apparatus according to the first embodiment. FIG. 2 is a schematic plan view of a vertical contraction type second transverse stretching machine used in the separator film manufacturing apparatus according to the first embodiment. FIG. 3 is a plan view showing the configuration of the clip chain shown in FIG. FIG. 4 is a sectional view taken along line f3 of FIG. 2, and is a sectional view at a position where the fixed block is arranged. FIG. 5 is a sectional view taken along line f5 of FIG. 2, and is a sectional view at a position where the rail moving mechanism is arranged. FIG. 6 is a plan view of the clip chain shown in FIG. 5, and is an explanatory view showing a state where the adjustment rail is in contact with the adjustment bearing. FIG. 7 is a block diagram showing an apparatus configuration of the separator film manufacturing apparatus according to the second embodiment. FIG. 8: is explanatory drawing which shows the relationship between the shrinkage rate at the time of conveyance of a raw film, and the heat shrinkage rate of the product film after conveyance. FIG. 9 is a graph of the test results shown in FIG.

Hereinafter, embodiments of a separator film manufacturing apparatus and a separator film manufacturing method according to the present disclosure will be described in detail with reference to the drawings. The present invention is not limited to this embodiment. Further, the constituent elements in the following embodiments include those that can be replaced by those skilled in the art and can be easily conceived, or those that are substantially the same.

[Embodiment 1]
FIG. 1 is a block diagram showing a device configuration of a separator film manufacturing apparatus 100 according to the first embodiment. The separator film manufacturing apparatus 100 according to the first embodiment is mainly used for manufacturing a separator film used in a lithium ion battery. The separator film manufacturing apparatus 100 includes a raw material supply apparatus 101, an extruder 102, a T die 103, a casting machine 104, a longitudinal stretching machine 105, a first transverse stretching machine 106, an extraction drying apparatus 107, and a longitudinal shrinkage. It has a mold second lateral stretching machine 110 and a winding machine 111.

In the following description, the transport direction of a member in the process of manufacturing a separator film by the separator film manufacturing apparatus 100 is also described as a longitudinal direction, which is a direction orthogonal to the transport direction, and a sheet or film described later. The width direction of will also be described as a horizontal direction.

The raw material supply device 101 is a device into which the raw material of the separator film manufactured by the separator film manufacturing device 100 is input and which supplies the input raw material to the extruder 102. A polyolefin resin and a liquid plasticizer are used as raw materials for the separator film. As the polyolefin-based resin, polyethylene or polypropylene is used, and for example, a polyethylene-based polymer material such as high-density polyethylene to which ultra-high molecular weight polyethylene is added is used. Further, as the liquid plasticizer, for example, oil or liquid paraffin is used. The raw material supply device 101 separately supplies the polyolefin resin, which is a raw material of the separator film, and the liquid plasticizer to the extruder 102.

The extruder 102 melt-kneads the polyolefin resin and the liquid plasticizer supplied from the raw material supply device 101. As the extruder 102, for example, a twin-screw kneading extruder having two screws is used, and the polyolefin resin and the liquid plasticizer are stirred by the two screws to form a slurry, and then melt-kneaded. Thereby, homogeneous and uniform melt-kneading is performed. The raw material melted and kneaded by the extruder 102 is sent to the T die 103 while suppressing pressure fluctuation using a gear pump (not shown) or the like.

The T die 103 discharges onto a slit-shaped sheet. The casting machine 104 is a roll device having a plurality of rolls, and cools and solidifies the sheet-shaped raw material discharged from the T die 103.

The longitudinal stretching machine 105 and the first transverse stretching machine 106 stretch the sheet that has been molded and cooled and solidified by the casting machine 104 to reduce the thickness of the sheet into a porous film-like raw film. Among these, the longitudinal stretching machine 105 has a plurality of rolls for transporting the sheet obtained by cooling and solidifying by the casting machine 104, and the transport speed is higher on the downstream side than on the upstream side in the transport direction. Is becoming The longitudinal stretching machine 105 conveys the sheet with a plurality of rolls having different conveying speeds while heating the sheet, thereby stretching the sheet in the conveying direction, that is, the longitudinal direction to form a film.

The first transverse stretching machine 106 grips both ends of the raw film stretched by the longitudinal stretching machine 105 in a direction orthogonal to the transport direction, that is, both ends in the lateral direction of the raw film, and transports the raw film in the longitudinal direction. While stretching, it is stretched in the transverse direction. As a result, the thickness of the original film that has been thinned by the longitudinal stretching machine 105 is further reduced. Here, the raw film formed by stretching the sheet conveyed from the casting machine 104 by the longitudinal stretching machine 105 and the first transverse stretching machine 106 is a polyolefin resin by stretching, A large number of fine holes are opened in the polyolefin resin, and the liquid plasticizer enters the fine holes. The porous film-shaped raw film stretched in the transverse direction by the first transverse stretching machine 106 is conveyed to the extraction/drying device 107.

The extraction/drying device 107 has an extraction device 108 and a drying device 109. The extraction device 108 extracts the liquid plasticizer impregnated in the original film conveyed from the first transverse stretching machine 106. Extraction of the liquid plasticizer is performed using methylene chloride, for example. That is, the extraction device 108 extracts the liquid plasticizer by immersing the raw film in a solution of methylene chloride while conveying the raw film, and removes the liquid plasticizer from the raw film. The drying device 109 dries while heating the raw film from which the liquid plasticizer has been removed. As a result, the drying device 109 removes methylene chloride attached to the raw film from which the liquid plasticizer has been removed, and dries it. The raw fabric film is a raw fabric film in which the liquid plasticizer is removed by the extraction/drying device 107, so that the liquid plasticizer escapes from a large number of fine pores formed in the polyolefin resin, and a large number of fine pores are formed. Become.

The raw film from which the liquid plasticizer has been extracted by the extraction/drying device 107 is conveyed to the vertical contraction type second transverse stretching machine 110. In the second vertical stretching machine 110, the raw film is stretched in the horizontal direction while being conveyed in the vertical direction, or is stretched in the horizontal direction and then contracted in the vertical direction. The vertical shrinkage type second horizontal stretching machine 110 is capable of vertically stretching the raw fabric film while transporting the raw fabric film in the vertical direction in this manner, and shrinking the transported raw fabric film in the vertical direction. Is provided as. The detailed configuration of the vertical contraction type second transverse stretching machine 110 will be described later.

The winding machine 111 winds the product film, which is a film after the original film is contracted in the longitudinal direction by the vertical contraction type second transverse stretching machine 110. Thus, the winder 111 rolls the product film. Separator film manufacturing apparatus 100 Among these apparatuses that are included, a raw material supply apparatus 101, an extruder 102, a T die 103, a casting machine 104, a longitudinal stretching machine 105, a first transverse stretching machine 106, an extraction drying apparatus 107, a winding machine. Since a device similar to a known device can be applied to the device 111, detailed description thereof will be omitted.

FIG. 2 is a schematic plan view of a vertical contraction type second transverse stretching machine 110 used in the separator film manufacturing apparatus 100 according to the first embodiment. In the following description, the first direction X and the second direction Y are directions orthogonal to each other on the horizontal plane, and the direction orthogonal to the first direction X and the second direction Y is defined as the third direction Z. The first direction X is a lateral direction when the original film 5a is conveyed by the vertical shrink type second horizontal stretching machine 110, and the second direction Y is the original film 5a by the vertical shrink type second horizontal stretching machine 110. Is a direction along the vertical direction, which is the transport direction of. The first direction X and the second direction Y are horizontal directions when the vertical contraction type second transverse stretching machine 110 is installed at an arbitrary installation location and used in a normal usage mode. The third direction Z is the vertical direction or the direction of gravity when the vertical contraction type second horizontal stretching machine 110 is installed at an arbitrary installation location and used in a normal usage mode. Further, in the following description, the upper side in the gravity direction when the vertical contraction type second horizontal stretching machine 110 is used in the normal usage mode is described as the upper side of the vertical contraction type second horizontal stretching machine 110, and the lower side in the gravity direction. The side will be described as the lower side of the second longitudinal stretching machine 110.

<Outline of longitudinal contraction type second transverse stretching machine 110>
The vertical contraction type second transverse stretching machine 110 has a left movement route 1L and a right movement route 1R, which are a pair of movement routes separated in the first direction X. The left movement path 1L has a series of left rail structures 4L in which the outward path 2 and the return path 3 are connected endlessly without intersecting each other. The right movement route 1R has a series of right rail structures 4R in which the outward route 2 and the return route 3 are connected endlessly without intersecting each other.

The left travel route 1L is arranged so that the outward route 2 and the return route 3 extend in the second direction Y in general. The rightward travel route 1R is arranged so that the forward path 2 and the backward path 3 extend in the second direction Y in the same manner as the leftward travel route 1L. Further, in the right movement route 1R, the outward route 2 faces the outward route 2 of the left movement route 1L, and the return route 3 faces the return route 3 of the left movement route 1L. A range between the outward path 2 of the left moving path 1L and the outward path 2 of the right moving path 1R is a carrying area 1A when the original film 5a is carried by the longitudinal contraction type second transverse stretching machine 110.

When the side where the center of the transport area 1A is located in the first direction X is the inner side and the opposite side of the side where the center of the transport area 1A is located in the first direction X is the outer side, the forward route 2 and the right route of the left movement route 1L The outward path 2 of the moving route 1R is arranged on both outer sides of the transport area 1A and extends along the transport area 1A in the second direction Y. Further, the return path 3 of the left movement path 1L is configured along the outside of the outward path 2 of the left movement path 1L in the first direction X, and the return path 3 of the right movement path 1R is configured as the right movement path in the first direction X. It is configured along the outside of the outward path 2 of 1R.

The longitudinal contraction type second transverse stretching machine 110 conveys the original film 5a in a direction in which the longitudinal direction is along the second direction Y. That is, the left rail structure 4L forming the left moving path 1L and the right rail structure 4R forming the right moving path 1R are arranged on both sides of the original film 5a in the first direction X so as to face each other. ing. In the region where the left rail structure 4L and the right rail structure 4R face each other, the left rail structure 4L and the right rail structure 4R are arranged such that both outward paths 2 face each other.

The left moving route 1L and the right moving route 1R have a symmetrical structure in the first direction X. That is, the left rail structure 4L and the right rail structure 4R have a symmetrical structure in the first direction X. In the following description, the left moving path 1L and the left rail structure 4L will be mainly described, but the right moving path 1R and the right rail structure 4R have the same structure. The structure described using the structure 4L is also applied to the right moving path 1R and the right rail structure 4R.

The forward path 2 and the backward path 3 of the left movement path 1L are an inlet side sprocket 6 located on the inlet side of the original film 5a and an outlet side sprocket located on the outlet side of the original film 5a when the original film 5a is conveyed. 7 are connected to each other endlessly. The inlet side sprocket 6 and the outlet side sprocket 7 are arranged on the left moving route 1L side and the right moving route 1R side, respectively. The outbound route 2 and the inbound route 3 of the left travel route 1L, and the outbound route 2 and the inbound route 3 of the right travel route 1R pass through the inlet side sprocket 6 and the outlet side sprocket 7 arranged on the respective moving

route

1L, 1R side. And each is endlessly continuous. For example, in the left movement route 1L, the outward route 2 is formed in the region from the inlet side sprocket 6 to the outlet side sprocket 7, and the return route 3 is in the region from the outlet side sprocket 7 to the inlet side sprocket 6. It is configured.

Of the inlet side sprocket 6 and the outlet side sprocket 7, the outlet side sprocket 7 is a drive side sprocket that is rotationally driven by a motor (not shown) used as a drive unit, and the inlet side sprocket 6 is a rotation-free sprocket. It is a driven sprocket composed of. That is, the motor applies a driving force to the outlet sprocket 7. The pair of outlet side sprockets 7 arranged on the left movement path 1L side and the right movement path 1R side may be rotated by a single motor via a rotation drive shaft, and the motors may be individually driven. It may be provided and rotated by each motor. Further, the inlet side sprocket 6 may also be rotationally driven by a motor (not shown) used as a drive unit, like the outlet side sprocket 7.

The left movement path 1L is provided with a clip chain 8 which is continuously formed along the left movement path 1L and is movable along the left rail structure 4L. The clip chain 8 is configured to be able to grip the edge portion of the original film 5a. The clip chain 8 provided on the left movement path 1L meshes with the inlet side sprocket 6 and the outlet side sprocket 7 arranged on the left movement path 1L side. As a result, the clip chain 8 provided on the left movement path 1L can circulate on the left movement path 1L by rotating the outlet side sprocket 7 by the motor.

Similarly, the right moving path 1R is also provided with a clip chain 9 which is continuously formed endlessly along the right moving path 1R and is movable along the right rail structure 4R. The edge of the original film 5a can be held. The left rail structure 4L, the clip chain 8, and the outlet side sprocket 7 that is rotationally driven by a motor (not shown) to move the clip chain 8 constitute a left grip device 40L. The right rail structure 4R, the clip chain 9, and the outlet side sprocket 7 that is rotationally driven by a motor (not shown) to move the clip chain 9 constitute a right grip device 40R. Therefore, the vertical contraction-type second horizontal stretching machine 110 includes a pair of

gripping devices

40L and 40R.

Further, in a region where the outward path 2 of the left movement path 1L and the outward path 2 of the right movement path 1R face each other, a series of conveyance areas 1A which are areas through which the original film 5a passes when the original film 5a is conveyed are configured. There is. The transport area 1A is configured to be continuous along the transport direction Y from the upstream side to the downstream side in the transport direction Y when transporting the raw film 5a by the second vertical contraction type horizontal stretching machine 110.

As for the outlet side sprocket 7 rotated by the driving force applied from the motor, the

clip chains

8 and 9 move along the forward path 2 from the inlet side sprocket 6 side toward the outlet side sprocket 7 side, and along the return path 3. It rotates in the direction of movement from the outlet side sprocket 7 side toward the inlet side sprocket 6 side.

Since the diameter of the outlet side sprocket 7 is larger than the distance between the outward route 2 and the return route 3 in a portion other than the portion where the outlet side sprocket 7 is disposed, the return route 3 includes the forward route 2 and the return route 3. An outlet side inclined portion 7p is provided which can gradually reduce the distance between the outlet side sprocket 7 and the distance.

The inlet side sprocket 6 that rotates with the movement of the

clip chains

8 and 9 moves toward the outward route 2 with the

clip chains

8 and 9 that have moved along the return path 3 from the outlet side sprocket 7 side toward the inlet side sprocket 6 side. Can be changed. Since the diameter of the inlet side sprocket 6 is larger than the distance between the outward route 2 and the return route 3 in a portion other than the portion where the inlet side sprocket 6 is disposed, the return route 3 has the forward route 2 and the return route 3. Is provided with an inlet side inclined portion 6p that can be gradually reduced as it is separated from the inlet side sprocket 6.

Furthermore, a heating device is provided in the transfer area 1A. The heating device includes an oven 30 and a temperature controller (not shown) that controls the temperature of the oven 30. In the transport direction Y of the left moving path 1L and the right moving path 1R, both the forward path 2 and the returning path 3 heat or heat the original film 5a in the region where the original film 5a is heated or kept warm. It is covered with an oven 30 for performing.

The oven 30 has a plurality of heating greenhouses T1 to T10. Note that, in FIG. 2, the heating greenhouses T1 to T10 have substantially the same size in the second direction Y, but the heating greenhouses T1 to T10 are different in type, stretching specification, etc. of the raw film 5a. Accordingly, the sizes in the second direction Y may be different from each other.

The temperature control unit controls the temperature of each of the heat-retaining greenhouses T1 to T10, and heats the inside of the heat-retaining greenhouses T1 to T10 up to a preset temperature, or maintains a constant temperature.

<Left rail structure 4L, right rail structure 4R>
The left rail structure 4L and the right rail structure 4R each include a forward rail unit 10 and a backward rail unit 11. The outward rail units 10 of both the left rail structure 4L and the right rail structure 4R are arranged along both outer sides of the transport area 1A in the first direction X. The return rail units 11 of both the left rail structure 4L and the right rail structure 4R are arranged along both outer sides of the forward rail unit 10 in the first direction X. The forward rail unit 10 and the backward rail unit 11 are in an area excluding the range from the inlet side inclined portion 6p in the transport direction Y to the upstream side and the range from the outlet side inclined portion 7p in the transport direction Y to the downstream side. It is provided.

Furthermore, the outward rail unit 10 and the inward rail unit 11 are each configured by connecting a plurality of block structures. FIG. 3 is a plan view showing the configuration of the

clip chains

8 and 9 shown in FIG. FIG. 4 is a sectional view taken along line f3 of FIG. 2, and is a sectional view at a position where the fixed block 16 is arranged. Specifically, the outward rail unit 10 is configured by connecting the outward blocks 13 (FIG. 4) having one block structure. The return path rail unit 11 is configured by connecting the return path block 14 (FIG. 4), which is the other block structure. A plurality of these forward path blocks 13 and return path blocks 14 are arranged side by side in the transport direction Y between the position where the inlet side sprocket 6 is arranged and the position where the outlet side sprocket 7 is arranged. Will be placed.

Further, in the vertical contraction type second transverse stretching machine 110, the rail moving mechanism 27 is applied to the interval adjustment range 27b-Z which is the range in which the transported raw film 5a contracts. The rail moving mechanism 27 can adjust the positional relationship between the outward path block 13 having one block structure and the return path block 14 having the other block structure.

<Outward rail unit 10>
The outward rail unit 10 is provided for each of the left moving route 1L and the right moving route 1R, and is continuously configured along the outgoing route 2 of the left moving route 1L and the right moving route 1R. The forward rail unit 10 includes an upper reference rail 10a and a lower reference rail 10b (see FIG. 4), and the upper reference rail 10a is located above the lower reference rail 10b in the gravity direction Z. There is. The upper reference rail 10a and the lower reference rail 10b are arranged parallel to each other in the state of being vertically separated from each other by a certain distance along the gravity direction Z.

The upper reference rail 10a is continuously laid along the outward path 2. The upper reference rail 10a is composed of a plurality of upper rail elements 10Ea. The plurality of upper rail elements 10Ea are fixed one by one to the plurality of outward path blocks 13 arranged along the transport direction Y, and are arranged in a line along the outward path 2.

Similarly, the lower reference rail 10b is also continuously laid along the outward path 2. The lower reference rail 10b is composed of a plurality of lower rail elements 10Eb. The plurality of lower rail elements 10Eb are fixed one by one to the plurality of outward path blocks 13 arranged along the transport direction Y, and are arranged in a line along the outward path 2.

The outward rail unit 10 is configured so that the moving mechanism 20 (see FIG. 3) included in the

clip chains

8 and 9 can move. The moving mechanism 20 has a traveling unit 25 and a rolling unit 26. The traveling unit 25 has an upper traveling bearing 25a and a lower traveling bearing 25b, and the rolling unit 26 has an upper rolling bearing 26a and a lower rolling bearing 26b. The details of these moving mechanisms 20 will be described later.

The upper reference rail 10a and the lower reference rail 10b have the same position in the width direction X, that is, the horizontal direction X, and are arranged side by side in the gravity direction Z. The upper traveling bearing 25a contacts the upper reference rail 10a from the lower side of the upper reference rail 10a in the gravity direction Z, and the lower traveling bearing 25b extends from the upper side of the lower reference rail 10b in the gravity direction Z to the lower reference rail. Contact 10b.

<Return rail unit 11>
The return path rail unit 11 is provided for each of the left moving path 1L and the right moving path 1R, and is continuously configured along the return path 3 of the left moving path 1L and the right moving path 1R. The return rail unit 11 includes an upper reference rail 11a and a lower reference rail 11b (see FIG. 4), and the upper reference rail 11a is located above the lower reference rail 11b in the gravity direction Z. There is. The upper reference rail 11a and the lower reference rail 11b are arranged parallel to each other in the state of being vertically separated from each other by a certain distance along the gravity direction Z.

The upper reference rail 11a is continuously laid along the return path 3. The upper reference rail 11a is composed of a plurality of upper rail elements 11Ea. The plurality of upper rail elements 11Ea are fixed one by one to the plurality of return path blocks 14 arranged along the transport direction Y, and are arranged in a line along the return path 3.

Similarly, the lower reference rail 11b is also laid continuously along the return path 3. The lower reference rail 11b is composed of a plurality of lower rail elements 11Eb. The plurality of lower rail elements 11Eb are fixed one by one to the plurality of return path blocks 14 arranged along the transport direction Y, and are arranged in a line along the return path 3.

The return rail unit 11 is configured so that the moving mechanism 20 (see FIG. 3) included in the

clip chains

8 and 9 can move. The upper reference rail 11a and the lower reference rail 11b have the same position in the lateral direction X and are arranged side by side in the gravity direction Z. The upper running bearing 25a contacts the upper reference rail 11a from the lower side of the upper reference rail 11a in the gravity direction Z, and the lower running bearing 25b moves from the upper side of the lower reference rail 11b in the gravity direction Z to the lower reference rail. Contact 11b.

<Rail block 12, forward block 13, return block 14>
The vertical contraction type second horizontal stretching machine 110 has a plurality of rail blocks 12. One rail block 12 is provided with a set of block structures including a forward block 13 and a backward block 14 (see FIG. 4). The left rail structure 4L and the right rail structure 4R are a series of endlessly connecting the forward path 2 and the backward path 3 by arranging a plurality of rail blocks 12 along the left moving path 1L and the right moving path 1R. The left rail structure 4L and the right rail structure 4R are configured.

Inside the rail block 12, a forward block 13 and a backward block 14 are arranged to face each other in the lateral direction X (see FIG. 4). The rail block 12 is configured such that the cross-sectional shape when viewed in the extending direction of the left moving path 1L and the right moving path 1R is configured to surround the outward block 13 and the backward block 14, and the side where the outward block 13 is located is the opening side. It has a U-shaped or U-shaped frame structure.

Inside the rail block 12, a slider 15 movable in the lateral direction X with respect to the rail block 12 is arranged, and the return path block 14 is fixed to the slider 15. As a result, the return path block 14 can be moved in the lateral direction X with respect to the rail block 12, and the positional relationship with the outward path block 13 in the lateral direction X can be adjusted.

The cross-sectional shape of each of the outward path block 13 and the inward path block 14 is U-shaped when viewed in the extending direction of the left moving path 1L and the right moving path 1R. Among these, the forward path block 13 has a U-shaped opening side facing the U-shaped opening side of the rail block 12, and the return path block 14 has a U-shaped opening side that is a U-shaped closed portion of the rail block 12. It is arranged so as to face the side wall portion 12c. Therefore, the forward path block 13 and the return path block 14 are arranged so that their U-shaped closed sides face each other.

The upper rail element 10Ea fixed to the outward block 13 is arranged in an upper portion of the forward block 13 having a U-shaped cross-section, and the lower rail element 10Eb has a downward cross-sectional shape of the forward block 13 having a U-shaped cross section. It is located in the lower part. Similarly, the upper rail element 11Ea fixed to the return path block 14 is arranged in the upper portion of the U-shaped cross section of the return path block 14, and the lower rail element 11Eb is the cross section of the return path block 14. It is located in the lower part of the letter shape.

In the rail block 12-P1 which is an example of the rail block 12 to which the rail moving mechanism 27 is not applied, a fixed block 16 is arranged and fixed between the forward block 13 and the backward block 14 as shown in FIG. There is. As a result, in the rail block 12-P1, the forward block 13 and the backward block 14 are arranged at a preset interval. The fixed blocks 16 are arranged in a preset number on one rail block 12-P1. For example, in the vicinity of both ends of the rail block 12-P1 in the direction along the left moving path 1L or the right moving path 1R. It is located in two places. The fixed block 16 is fixed to the outward block 13 and the return block 14 by a plurality of bolts 17.

5 is a sectional view taken along line f5 of FIG. 2, and is a sectional view at a position where the rail moving mechanism 27 is arranged. Note that FIG. 5 is a cross-sectional view of one rail block 12 indicated by reference numeral 12-P2 in FIG. In the distance adjustment range 27b-Z (see FIG. 2), the distance between the forward path block 13 and the backward path block 14 can be adjusted by the rail moving mechanism 27.

In the rail block 12-P2, which is an example of the rail block 12 to which the rail moving mechanism 27 is applied, as shown in FIG. 5, an adjustment block forming the rail moving mechanism 27 is provided between the forward block 13 and the backward block 14. 27a is arranged. A preset number of adjustment blocks 27a are arranged on one rail block 12-P2, and for example, the adjustment blocks 27a are provided near both ends of the rail block 12-P2 in the direction along the left movement path 1L or the right movement path 1R. It is located in two places. The adjustment block 27a is fixed to the return path block 14 by a plurality of bolts 28.

Further, an adjustment passage 27d that constitutes the rail moving mechanism 27 is formed at a position facing the adjustment block 27a in the outward block 13. The adjustment passage 27d is formed as a hole penetrating the outward block 13 in the lateral direction X, and can be inserted through the adjustment block 27a. The adjustment block 27 a fixed to the return path block 14 enters the adjustment path 27 d formed in the outward path block 13.

On the side of the rail block 12-P2 where the side wall portion 12c is located, an adjusting screw 27e that constitutes the rail moving mechanism 27 is provided. The side wall portion 12c is formed with a screw hole that is screwed into a screw portion formed in the adjusting screw 27e. The adjusting screw 27e is configured such that the screw portion is screwed into the screw hole, so that the side wall portion 12c is laterally moved. It penetrates through X and is supported by the side wall portion 12c. The adjustment screw 27e is rotatably connected to the slider 15 by being connected to the bearing 29 attached to the slider 15 at the tip end side. On the other hand, the opposite end of the adjusting screw 27e, that is, the base end side of the adjusting screw 27e is located outside the oven 30 (see FIG. 2). As a result, the adjusting screw 27e can be operated from the outside of the oven 30.

<

Clip chains

8, 9>
The vertical contraction type second horizontal stretching machine 110 has

endless clip chains

8 and 9 that can move along the left moving path 1L and the right moving path 1R. The clip chain 8 on the left movement route 1L side and the clip chain 9 on the right movement route 1R side have the same configuration. The

clip chains

8 and 9 are arranged at both ends of the original film 5a in the lateral direction X so that the original film 5a can be grasped and stretched. The

clip chains

8 and 9 are respectively provided on the inlet side sprocket 6 and the outlet side sprocket 7. It is wrapped around.

The

clip chains

8 and 9 are provided with a plurality of clips 18 for holding the original film 5a, a plurality of gap adjusting mechanisms 19, and a plurality of moving mechanisms 20 (see FIG. 3). The

clip chains

8 and 9 are configured by alternately connecting one clip 18 and one space adjustment mechanism 19 in an endless manner. Further, one moving mechanism 20 is mounted on each clip 18. The moving mechanism 20 is configured to be able to move the clip 18 along the forward rail unit 10 and the backward rail unit 11.

The forward path 2 of the left moving path 1L and the forward path 2 of the right moving path 1R (see FIG. 2) are provided with the clip 18 from the upstream side to the downstream side in the transport direction Y when transporting the raw film 5a held by the clip 18. It is a route to move. The return path 3 of the left movement path 1L and the return path 3 of the right movement path 1R are paths for moving the clip 18 from the downstream side to the upstream side in the transport direction Y (see FIG. 2).

<Clip 18>
The clip 18 includes a clip body 18a and a gripping member 18p (see FIG. 3). The clip body portion 18a includes a support surface 18Sa (see FIG. 4) that is a portion that holds both edges of the original film 5a in the lateral direction X with the holding member 18p.

The gripping member 18p is rotatably supported by the clip body 18a (see FIG. 4). The portion of the clip body 18a that supports the gripping member 18p is located above the support surface 18Sa, and the gripping member 18p has the gripping surface 18Sp at the pivoting tip located on the support surface 18Sa side. ing. The gripping member 18p can grip both edges of the raw film 5a by sandwiching the raw film 5a between the gripping surface 18Sp and the supporting surface 18Sa.

<Interval adjustment mechanism 19>
The interval adjusting mechanism 19 is arranged between two adjacent clips 18 along the transport direction Y or the moving direction of the clip chains 8 and 9 (see FIG. 3 ). That is, the plurality of clips 18 and the plurality of interval adjusting mechanisms 19 are alternately connected endlessly one by one, and the interval adjusting mechanism 19 connects adjacent clips 18 of the plurality of clips 18 to each other. ing. The space adjusting mechanism 19 has a function of adjusting the space between the adjacent clips 18. Here, for convenience of description, of the two clips 18 adjacent to each other in the transport direction Y, one clip 18 will be described as a first clip 18-1 and the other clip 18 will be described as a second clip 18-2. ..

The space adjusting mechanism 19 includes a first joint member 19-1 and a second joint member 19-2. The clip main body portion 18a is formed in a U-shaped cross-sectional shape when the clip main body portion 18a is viewed in the moving direction of the clip 18, and the side on which the support surface 18Sa is located is the closed side. The member 19-1 and the second joint member 19-2 are arranged in a U-shaped inner portion. One end of the first joint member 19-1 in the length direction is rotatably connected to the clip body portion 18a of the first clip 18-1 via the first pivot portion 21 extending in the gravity direction Z. .. The other end of the first joint member 19-1 in the length direction is rotatably connected to the second joint member 19-2 via the relay shaft portion 22.

The second joint member 19-2 has a substantially doglegged shape, one end of which is rotatably connected to the relay shaft portion 22 and the other end of which is rotatably attached an adjusting bearing 19-3. Specifically, the second joint member 19-2 extends from the bent portion 19-2c, which is a bent portion of the substantially doglegged shape, to the side where the first joint member 19-1 is located. 19-2a and a protruding portion 19-2b extending from the bent portion 19-2c to the side opposite to the side where the gripping member 18p is located in the lateral direction X. The second joint member 19-2 is rotatably connected to the clip body portion 18a of the second clip 18-2 at the position of the bent portion 19-2c by the second pivot portion 24 extending in the gravity direction Z. In addition, the second joint member 19-2 has the end portion of the second joint main body portion 19-2a rotatably connected to the relay shaft portion 22, so that the second joint member 19-2 itself is connected to the relay shaft portion. It is rotatably connected to the first joint member 19-1 via 22.

The projecting portion 19-2b of the second joint member 19-2 projects from the bent portion 19-2c to the side opposite to the side where the gripping member 18p is located in the lateral direction X, and further the first clip 18-1 is located therein. It is formed to be curved in the direction. The adjustment bearing 19-3 is rotatably attached to the tip of the protruding portion 19-2b of the second joint member 19-2 so that the rotation axis is in the direction along the gravity direction Z.

Since the gap adjusting mechanism 19 is configured as described above, the first clip 18-1 and the second clip 18-2 are the same as the first joint member 19-1 and the second joint member 19- of the gap adjusting mechanism 19. 2 rotates with respect to the first clip 18-1 and the second clip 18-2, and the first joint member 19-1 and the second joint member 19-2 rotate relative to each other. The distance between the first clip 18-1 and the second clip 18-2 can be changed. Thereby, the interval adjusting mechanism 19 connects the two adjacent clips 18 so that the interval between the two adjacent clips 18 in the transport direction Y can be changed. In the first embodiment, the gap adjusting mechanism 19 is capable of reducing the gap between the two adjacent clips 18 by about 20% with respect to the maximum gap between the two clips 18.

<Movement mechanism 20>
The moving mechanism 20 has a traveling unit 25 and a rolling unit 26 arranged on both the upper side and the lower side of the clip 18 in the gravity direction Z (see FIG. 4 ). The moving mechanisms 20 are mounted on the clips 18 one by one, and the clips 18 can be moved along the left moving path 1L and the right moving path 1R.

The upper traveling bearing 25a included in the traveling unit 25 is disposed on the upper wall portion of the clip main body portion 18a formed in a U-shaped cross section, and the lower traveling bearing 25b includes the upper portion of the clip main body portion 18a. It is located on the lower wall. The upper running bearing 25a and the lower running bearing 25b are both arranged such that their rotation axes extend in a direction orthogonal to both the moving direction of the clip 18 and the gravity direction Z.

The upper traveling bearing 25a contacts the upper reference rail 10a of the forward rail unit 10 and the upper reference rail 11a of the return rail unit 11 from below. The lower traveling bearing 25b contacts the lower reference rail 10b of the forward rail unit 10 and the lower reference rail 11b of the return rail unit 11 from above. This allows the traveling unit 25 to move along the forward rail unit 10 and the backward rail unit 11 while the upper traveling bearing 25a and the lower traveling bearing 25b roll.

The upper rolling bearing 26a of the rolling unit 26 is arranged on the upper surface side of the clip body 18a, and the lower rolling bearing 26b is arranged on the lower surface side of the clip body 18a. The upper rolling bearing 26a and the lower rolling bearing 26b are both arranged such that the rotation axis extends in the gravity direction Z. The upper rolling bearing 26a contacts the upper reference rail 10a of the forward rail unit 10 and the upper reference rail 11a of the return rail unit 11 from the side in the horizontal direction. The lower rolling bearing 26b contacts the lower reference rail 10b of the outward rail unit 10 and the lower reference rail 11b of the return rail unit 11 from the side in the horizontal direction.

Specifically, four upper rolling bearings 26a are arranged in one clip body portion 18a, and four upper rolling bearings 26a are provided on each side of the

upper reference rails

10a and 11a in the thickness direction. Are arranged one by one. Similarly, four lower rolling bearings 26b are arranged in one clip body portion 18a, and four lower rolling bearings 26b are provided on each side of the

lower reference rails

10b and 11b in the thickness direction. Are arranged one by one. As a result, the rolling unit 26 can move along the forward rail unit 10 and the backward rail unit 11 while the upper rolling bearing 26a and the lower rolling bearing 26b roll.

<Rail movement mechanism 27>
The rail moving mechanism 27 is provided over an interval adjustment range 27b-Z (see FIG. 2). It is set in a range from the position to start to at least the grip release point 18p-OFF. The grip release point 18p-OFF is a position where the grip on the clip 18 is released when the original film 5a is conveyed in the conveyance direction Y while being grasped by the clip 18.

When the original film 5a is conveyed by the vertical contraction-type second transverse stretching machine 110, in the interval adjustment range 27b-Z, a lateral relaxation process for following contraction of the original film 5a along the transverse direction X and a conveying direction. A longitudinal relaxation process is performed so as to follow the contraction of the original film 5a along Y. The rail moving mechanism 27 can adjust the interval between the clips 18 adjacent to each other in the transport direction Y on the outward path 2 by moving the adjustment rail 27b that constitutes the rail moving mechanism 27, and as a result, The rail moving mechanism 27 is capable of performing a longitudinal relaxation process. That is, the vertical shrinkable second horizontal stretching machine 110 can shrink the original film 5a in the longitudinal direction Y, which is the transport direction Y, by adjusting the interval between the clips 18.

The rail moving mechanism 27 has an adjusting block 27a, an adjusting rail 27b, an adjusting passage 27d, and an adjusting screw 27e (see FIG. 5). As described above, in the adjustment block 27a, a preset number of adjustment blocks 27a are fixed to the return path block 14 by a plurality of bolts 28.

The adjustment rail 27b is a rail arranged to adjust the interval between the clips 18, and is provided on the positioning block 31. The positioning block 31 is supported on the opposite side of the adjusting block 27a in the lateral direction X from the side fixed to the return path block 14. The adjusting rail 27b is arranged so as to face the positioning block 31 supported by the adjusting block 27a and the adjusting bearing 19-3 attached to the second joint member 19-2 of the interval adjusting mechanism 19 (see FIG. 3). And is arranged so as to be able to contact the adjusting bearing 19-3. As a result, the adjustment rail 27b moves in a direction in which the support surface 18Sa of the clip 18 and the gripping member 18p are positioned in the lateral direction X with respect to the adjustment bearing 19-3 attached to the second joint member 19-2 of the gap adjusting mechanism 19. It is possible to apply a pressing force to. That is, in the interval adjusting mechanism 19, the adjusting bearing 19-3 comes into contact with the adjusting rail 27b, and the pressing force from the adjusting rail 27b acts to adjust the interval of the clips 18.

The adjustment passage 27d is formed as a hole penetrating the outward block 13 in the lateral direction X at a position facing the adjustment block 27a fixed to the return block 14 and the positioning block 31 in the outward block 13. The adjustment passage 27d is configured so that not only the adjustment block 27a but also the positioning block 31 can be inserted, and the adjustment block 27a and the positioning block 31 enter the adjustment passage 27d.

As described above, the adjusting screw 27e is supported by the side wall portion 12c by screwing the screw portion into the screw hole formed in the side wall portion 12c of the rail block 12, and the tip side is attached to the slider 15. It is connected to the slider 15 via a bearing 29. Further, the end of the adjusting screw 27e opposite to the end connected to the slider 15 is located outside the oven 30.

<Operation of the vertical contraction type second horizontal stretching machine 110>
The vertical shrinkage type second transverse stretching machine 110 included in the separator film manufacturing apparatus 100 according to the first embodiment includes the above-described configuration, and its operation will be described below. At the time of manufacturing the separator film by the separator film manufacturing apparatus 100, the liquid plasticizer is extracted by the extraction/drying device 107, and the raw film 5a having a large number of fine holes opened vertically contracts from the extraction/drying device 107 (see FIG. 1). The mold is conveyed to the second transverse stretching machine 110. The vertical contraction type second transverse stretching machine 110 positions the raw film 5a transported from the extraction/drying device 107 in the transport area 1A from the side where the inlet side sprocket 6 is positioned (see FIG. 2). At that time, in the original film 5a, the longitudinal direction of the original film 5a, that is, the longitudinal direction is the second direction Y of the vertical contraction-type second transverse stretching machine 110. It is positioned in the transport area 1A in the width direction orthogonal to both the directions, that is, in the direction in which the lateral direction is the first direction X of the second longitudinal contraction type horizontal stretching machine 110.

The raw film 5a fed from the entrance-side sprocket 6 side of the transport area 1A to the transport area 1A from a device such as the extraction/drying device 107 used in the preceding step of the vertical shrinkage type second horizontal stretching machine 110 is gripped in the forward path 2. At the starting point 18p-ON, both edges in the lateral direction X are sequentially gripped by the clip 18. The gripping start point 18p-ON mentioned here is such that the original film 5a is directed from the inlet side sprocket 6 side toward the outlet side sprocket 7 side while gripping the original film 5a by the clip 18 forming the

clip chains

8 and 9. The position is such that the clip 18 starts gripping the original film 5a during transportation.

When gripping both edges of the original film 5a with the clip 18, the gripping member 18p rotatably supported by the clip body 18a is rotated (see FIG. 4). As a result, the vicinity of both edges of the original film 5a in the lateral direction X is sandwiched between the holding surface 18Sp of the holding member 18p and the support surface 18Sa of the clip body 18a, and the vicinity of both edges of the original film 5a is clipped. Hold by 18.

The original film 5a is conveyed by driving a motor that applies a driving force to the outlet side sprocket 7 while the original film 5a is being held by the clips 18 forming the clip chains 8 and 9 (FIG. 2). reference). As a result, the clip chain 8 provided on the left moving path 1L circulates on the left moving path 1L by the driving force transmitted from the outlet side sprocket 7, and the clip chain 9 provided on the right moving path 1R moves toward the outlet side sprocket 7. The driving force transmitted from the vehicle circulates in the right movement path 1R.

The circulation direction of the

clip chains

8 and 9 is such that the

clip chains

8 and 9 move from the inlet side sprocket 6 side toward the outlet side sprocket 7 side in the forward path 2 of the left movement path 1L and the right movement path 1R, and the left movement path. In the return path 3 of 1L or the right movement path 1R, the

clip chains

8 and 9 are in the direction of moving from the outlet side sprocket 7 side toward the inlet side sprocket 6 side. The original film 5a has both edges in the lateral direction X gripped by the clip 18 at the position of the outward path 2 of the left moving path 1L or the right moving path 1R, so that the

clip chains

8 and 9 circulate, and The anti-film 5a is moved in the moving direction of the

clip chains

8 and 9 in the outward path 2 by the

clip chains

8 and 9 located in the outward path 2. Therefore, the original film 5a moves in the transport area 1A from the inlet sprocket 6 side in the transport direction Y toward the outlet sprocket 7 side.

The raw film 5a transported in the transport area 1A is stretched in the lateral direction X while being heated while being transported, for example, stretched 1.1 to 1.7 times in the lateral direction X. As a result, when the original film 5a is sent out from the side where the outlet side sprocket 7 is located, the product film 5b which is a stretched film is sent out.

Specifically, the transport area 1A is provided with a plurality of heat-retaining greenhouses T1 to T10, each of which is capable of temperature control, and the heat-retaining greenhouses T1 to T10 are arranged at respective positions in the transport direction Y. It is possible to heat the original film 5a at a temperature according to the above. In other words, in each of the heating greenhouses T1 to T10, the temperature of the oven 30 suitable for the position in the transport direction Y is controlled in each of the heating greenhouses T1 to T10.

In addition, the distance in the lateral direction X between the outward paths 2 of the left moving path 1L and the right moving path 1R is different for each position in the carrying direction Y, and within a predetermined range in the carrying direction Y, from the inlet side sprocket 6 side. The distance between the two outward paths 2 becomes larger toward the exit side sprocket 7 side. That is, in a predetermined range in the transport direction Y, the distance in the lateral direction X between the clips 18 holding both ends of the original film 5a in the lateral direction X increases in the direction from the inlet side sprocket 6 side toward the outlet side sprocket 7 side. It is like this. Thereby, the longitudinal contraction type second transverse stretching machine 110 heats the original film 5a by the oven 30 when the original film 5a is conveyed in the conveyance area 1A, and the lateral direction X with respect to the original film 5a. Is applied to stretch in the transverse direction X. That is, in a region where the distance between the outward paths 2 of the left moving path 1L and the right moving path 1R increases from the inlet side sprocket 6 side toward the outlet side sprocket 7 side, by running the

clip chains

8 and 9, The original film 5a is stretched in the transverse direction X while the film 5a is conveyed in the conveying direction Y. As a result, the size of the fine holes formed in the original film 5a is adjusted.

Further, the vertical contraction-type second horizontal stretching machine 110 is configured such that, in the transport direction Y, the original film in the lateral direction X is within a predetermined range on the outlet sprocket 7 side with respect to the range in which the original film 5a is stretched in the lateral direction X. The distance between the outward paths 2 located on both sides of 5a becomes smaller from the inlet side sprocket 6 side toward the outlet side sprocket 7 side. That is, in a predetermined range located on the outlet side sprocket 7 side with respect to the range in which the original film 5a is stretched in the lateral direction X, the distance in the lateral direction X between the clips 18 for gripping both ends in the lateral direction X of the original film 5a. However, it becomes smaller as it goes from the inlet side sprocket 6 side toward the outlet side sprocket 7 side. Therefore, in this range, the original film 5a contracts in the lateral direction X as being conveyed from the inlet side sprocket 6 side to the outlet side sprocket 7 side. In the range in which the original film 5a is contracted in the lateral direction X, for example, it is contracted in the lateral direction X by about 10% to 30%.

Here, when the raw film 5a shrinks, it also shrinks in the transport direction Y, that is, in the vertical direction Y. Therefore, in the range in which the raw film 5a shrinks in the vertical direction Y, the distance between the adjacent clips 18 is small. Is reduced by moving the adjusting rail 27b by the rail moving mechanism 27 arranged in the interval adjusting range 27b-Z. In other words, the space adjustment range 27b-Z is a range including the range in which the original film 5a shrinks in the outward path 2. When adjusting the distance between the adjacent clips 18 by the rail moving mechanism 27 (see FIG. 5), the adjustment screw 27e that constitutes the rail moving mechanism 27 is rotated.

Since the adjusting screw 27e is screwed into the side wall portion 12c of the rail block 12, when the adjusting screw 27e is rotated, the adjusting screw 27e moves in the lateral direction X, and the slider 15 moves in the lateral direction X together with the adjusting screw 27e. Moving. As a result, the return path block 14 also moves in the lateral direction X together with the slider 15, and the adjustment block 27a fixed to the return path block 14 also moves together with the return path block 14. When the adjusting block 27a is moved together with the return path block 14 by a preset distance by rotating the adjusting screw 27e, the rotation of the adjusting screw 27e is stopped.

When the adjustment block 27a moves in the lateral direction X, the positioning block 31 supported by the adjustment block 27a and the adjustment rail 27b provided on the positioning block 31 also move together with the adjustment block 27a. For example, when the return path block 14 moves toward the side where the outward path block 13 is located in the lateral direction X by rotating the adjustment screw 27e, the adjustment rail 27b, which moves in the same direction as the positioning block 31, moves in the same direction as the adjustment bearing 19. Contact -3.

FIG. 6 is a plan view of the

clip chains

8 and 9 shown in FIG. 5, and is an explanatory view showing a state in which the adjustment rail 27b is in contact with the adjustment bearing 19-3. When the adjusting rail 27b comes into contact with the adjusting bearing 19-3, a pressing force acts on the adjusting bearing 19-3 from the adjusting rail 27b. The pressing force acting on the adjusting bearing 19-3 from the adjusting rail 27b is a force for moving the adjusting bearing 19-3 in the lateral direction X to the side where the gripping member 18p of the clip 18 is located with respect to the adjusting bearing 19-3. To work. In the space adjusting mechanism 19, the second joint member 19-2, to which the adjusting bearing 19-3 is attached, rotates about the second pivot portion 24 by the pressing force acting on the adjusting bearing 19-3 from the adjusting rail 27b. .. Accordingly, in the second joint member 19-2, the end of the second joint body 19-2a on the side where the relay shaft 22 is located moves in the lateral direction X toward the side on which the gripping member 18p is located. The entire second joint member 19-2 rotates about the second pivot portion 24.

When the relay shaft portion 22 moves in the lateral direction X due to the rotation of the second joint member 19-2, the first joint member 19-1 connected to the second joint member 19-2 via the relay shaft portion 22 also The entire first joint member 19-1 rotates about the first pivot portion 21. Therefore, in the space adjusting mechanism 19, the first joint member 19-1 and the second joint body portion 19-2a of the second joint member 19-2, the relay shaft portion 22 in the lateral direction X, and the gripping member 18p are arranged. Bends around the relay shaft portion 22 in the direction of moving to the position side.

When the first joint member 19-1 and the second joint member 19-2 are bent, the first pivot portion 21 connecting the first joint member 19-1 to the first clip 18-1 and the second joint member 19- The second pivot portion 24 connecting the second clip 18-2 and the second clip portion 18-2 comes close to each other, and the distance becomes smaller. As a result, the distance between the first clip 18-1 and the second clip 18-2, which are connected to the interval adjusting mechanism 19 via the first pivot portion 21 and the second pivot portion 24, is also reduced, and the two adjacent ones. The distance between the clips 18 becomes smaller.

On the contrary, by rotating the adjusting screw 27e, when the return path block 14 moves in the direction away from the side where the forward path block 13 is located in the lateral direction X, the adjusting rail 27b is also moved from the side where the forward path block 13 is located. Move away. When the adjustment rail 27b moves in the direction away from the outward block 13 in the lateral direction X, the adjustment rail 27b is brought into a non-contact state where it does not contact the adjustment bearing 19-3 or a weak contact state where the pushing amount is small. When the adjusting rail 27b comes into non-contact with the adjusting bearing 19-3, the pressing force from the adjusting rail 27b does not act on the adjusting bearing 19-3.

When the pressing force does not act on the adjustment bearing 19-3, the first joint member 19-1 and the second joint member 19-2 of the space adjusting mechanism 19 are connected to the

clip chains

8 and 9 from the outlet side sprocket 7. The tension acting as a result increases the distance between the first pivot portion 21 and the second pivot portion 24 in the vertical direction Y. Accordingly, in the interval adjusting mechanism 19, the first pivot portion 21, the second pivot portion 24, and the relay shaft portion 22 are located on a straight line, and the first joint member 19-1 and the second joint member 19-2 are The second joint body 19-2a and the second joint body 19-2a are in a deployed state (see FIG. 3). Therefore, the distance between the first clip 18-1 and the second clip 18-2 connected to the interval adjusting mechanism 19 via the first pivot portion 21 and the second pivot portion 24 also becomes large. Since tension is applied from the outlet side sprocket 7 to the

clip chains

8 and 9 in the direction in which the distance between adjacent clips 18 increases, the pressing force from the adjusting rail 27b does not act on the adjusting bearing 19-3. In the state, the distance between the adjacent clips 18 becomes maximum.

On the other hand, when the contact state of the adjusting rail 27b with respect to the adjusting bearing 19-3 is the weak contact state, the pushing amount acting on the adjusting bearing 19-3 from the adjusting rail 27b becomes small. In this state, the amount of bending between the first joint member 19-1 of the space adjusting mechanism 19 and the second joint body portion 19-2a of the second joint member 19-2 changes from the adjusting rail 27b to the adjusting bearing 19-3. It becomes smaller than the bending amount in the state where the pushing amount acting is large. As a result, the distance between the adjacent clips 18 is also the distance in the state in which the amount of push-in that acts on the adjustment bearing 19-3 from the adjustment rail 27b is large, and the distance in the state in which the adjustment rail 27b does not contact the adjustment bearing 19-3. It becomes the size of the space.

The adjustment of the interval between the adjacent clips 18 by the rail moving mechanism 27 applied to the interval adjustment range 27b-Z is performed by rotating the adjustment screw 27e in this manner to adjust the interval between the two adjacent clips 18 to each other. Make it larger or smaller. Further, in the part of the outward path 2 other than the interval adjustment range 27b-Z, the interval between the adjacent clips 18 is not adjusted by the rail moving mechanism 27, so that the adjacent clips 18 have the maximum interval. Is maintained.

The adjustment of the interval between the adjacent clips 18 by rotating the adjustment screw 27e may be performed manually or automatically. In the manual adjustment, it is preferable to provide the adjustment screw 27e with a scale that can be visually confirmed by the operator. On the other hand, in the automatic adjustment, it is preferable to provide a motor that can be connected to the adjustment screw 27e and a detection device that can detect a rotation state such as a rotation angle of the motor.

In the range in which the original film 5a shrinks in the longitudinal direction Y, the distance between the clips 18 is reduced by the rail moving mechanism 27 in this way, so that the original film 5a is moved not only in the lateral direction X but also in the longitudinal direction Y. Also shrink. That is, in the range in which the original film 5a shrinks, the interval between the outward paths 2 is reduced to reduce the restraint of the original film 5a in the lateral direction X, and the interval between the clips 18 is reduced to decrease the original film. The restraint in the vertical direction Y of the film 5a is reduced. Thereby, the distance between the clips 18 in the horizontal direction X and the distance between the clips 18 in the vertical direction Y are made to follow the contraction of the original film 5a, and the original film 5a is appropriately maintained while maintaining a constant tension. Contract. The vertical contraction-type second horizontal stretching machine 110 according to the first exemplary embodiment can reduce the interval between the clips 18 in the vertical direction Y within a range from the maximum interval to the interval that reduces it by 20%. The original film 5a can be shrunk in the vertical direction Y.

In the method for manufacturing the separator film according to the first embodiment, the original film 5a is conveyed in the vertical direction Y by reducing the interval between the clips 18 in the range in which the original film 5a is contracted in the vertical direction Y. The contraction rate in the vertical direction Y is contracted in the vertical direction Y within the range of 6% to 20%. That is, the contraction of the original film 5a in the longitudinal direction Y is performed by reducing the interval between the clips 18, so that the original film 5a is contracted in the longitudinal direction Y in the range in which the original film 5a is contracted in the longitudinal direction Y. While being transported, the contraction rate in the vertical direction Y of the clips 18, which is the interval between the clips 18, is contracted in the vertical direction Y within the range of 6% or more and 20% or less. Specifically, in the range in which the original film 5a is contracted in the longitudinal direction Y, the distance between the clips 18 at the start position of the range in the transport direction of the original film 5a is different from that between the clips 18 at the end position of the range. The interval between the clips 18 is contracted in the vertical direction Y within a range in which the contraction rate of the interval is 6% or more and 20% or less.

In the range where the original film 5a is contracted in the longitudinal direction Y, the longitudinal contraction type second transverse stretching machine 110 contracts the original film 5a in the longitudinal direction Y by thus reducing the interval between the clips 18. The shrinkage ratio of the length in the longitudinal direction Y of the raw fabric film 5 after passing through this range is 6% or more and 20% or less with respect to the length in the longitudinal direction Y of the raw fabric film 5a before passing through the range. The original film 5a is shrunk within the range. As a result, the vertical contraction type second transverse stretching machine 110 grips the raw film 5a at the grip start point 18p-ON, then conveys it in the longitudinal direction Y and grips the raw film 5a at the grip release point 18p-OFF. Until the release, the original film 5a is contracted in the vertical direction Y while being conveyed in the vertical direction Y. In the vertical shrinkage type second horizontal stretching machine 110, the distance between the clips 18 in the horizontal direction X and the vertical direction Y is thus reduced to shrink the raw film 5a in both the horizontal direction X and the vertical direction Y. Thus, the residual stress generated when the original film 5a is stretched is removed.

The product film 5b, which is a film from which residual stress generated when the original film 5a is stretched due to the completion of the heat treatment, is conveyed to the outlet side sprocket 7 side, and both edges are clipped at the grip release point 18p-OFF. Freed from 18. That is, each clip 18 that moves while gripping the product film 5b releases the grip of the product film 5b when it reaches the grip release point 18p-OFF. As a result, the product film 5b that has been stretched by the vertical shrinkage type second horizontal stretching machine 110, and that has residual stress removed by being further shrunk, is sent to the winder 111.

On the other hand, the clips 18 of the

clip chains

8 and 9 that have released the grip of the product film 5b at the grip release point 18p-OFF reach the outlet sprocket 7 by the rotation of the outlet sprocket 7, and then return from the outlet sprocket 7 to the return path 3 Sent to the side. The clip 18 sent to the return path 3 moves from the exit side sprocket 7 side to the entrance side sprocket 6 side through the return path 3, moves again to the forward path 2 via the entrance side sprocket 6, and the grip start point 18p− When it is ON, the original film 5a is gripped. The clip 18 conveys the original film 5a by moving the outward path 2 from the inlet side sprocket 6 side toward the outlet side sprocket 7 side while holding the original film 5a.

<Effect of Embodiment 1>
As described above, in the separator film manufacturing apparatus 100 according to the first embodiment and the separator film manufacturing method according to the first embodiment, a liquid plasticizer is extracted by the extraction/drying device 107 to open many fine holes. The original fabric film 5a is stretched in the transverse direction X by a vertical contraction type second transverse stretching machine 110 which is a longitudinal contraction type heat treatment device arranged on the post-process side of the extraction drying device 107, and the raw fabric film 5a is further formed. By adjusting the distance between the gripped clips 18, the horizontal direction X and the vertical direction Y are contracted. As a result, the size of the fine holes is adjusted by stretching in the transverse direction X, and both the residual stress in the transverse direction X and the residual stress in the longitudinal direction Y generated in the original film 5a are eliminated. It can be removed by shrinking 5a. That is, the residual stress in the lateral direction X can be removed by contracting the original film 5a in the lateral direction X, and the residual stress in the longitudinal direction Y can be removed by contracting the original film 5a in the longitudinal direction Y. be able to. Therefore, thermal shrinkage of the product film 5b in the vertical direction Y due to residual stress in the vertical direction Y can be suppressed.

Therefore, after the raw film 5a is stretched and shrunk in the transverse direction X by the vertical shrink type second horizontal stretching machine 110, the product film 5b can be obtained without increasing the exposure time at high temperature or performing roll annealing or aging. The vertical heat shrinkage rate of As a result, a separator film used in a lithium-ion battery can be provided while suppressing the provision of equipment for roll annealing or aging, and suppressing the exposure time at a high temperature in the vertical contraction type second transverse stretching machine 110 for a long time. The longitudinal heat shrinkage of the product film 5b used for can be reduced. As a result, the longitudinal heat shrinkage rate of the separator film can be reduced while suppressing the increase in manufacturing time and the complexity of the apparatus configuration.

Roll annealing is a process of removing the internal stress of the film by passing the film through a plurality of heating rolls, but since the width dimension cannot be regulated, the film is not limited to the longitudinal direction Y but to the lateral direction X. May contract. Therefore, the size of the film in the lateral direction X may be smaller than the desired size. On the other hand, when the residual film in the longitudinal direction Y is removed by contracting in the longitudinal direction Y after stretching the raw film 5a in the longitudinal contraction type second transverse stretching machine 110, both ends are Since it can be heat-treated in a tension state in which the film tension is maintained by sandwiching the film, it is possible to suppress thermal contraction after the product film 5b is fed from the vertical contraction type second transverse stretching machine 110 and prevent occurrence of unevenness due to contraction. You can As a result, the manufacturing accuracy of the product film 5b can be improved.

Further, aging is a process of reducing residual stress by extracting the liquid plasticizer, drying it, and stretching the product film 5b after stretching it in the transverse direction X at a relatively high temperature for a long time to reduce residual stress. , The processing time becomes longer. For example, in aging, since it is necessary to leave the product film 5b after being stretched in the transverse direction X in the temperature region of 60° C. for one day, the work film 5b cannot be worked for a long time. The time required for manufacturing the separator film is substantially increased. Further, since the rolled product film 5b contracts, wrinkles may occur. On the other hand, in the case of removing the residual stress in the longitudinal direction Y by stretching the raw fabric film 5a in the transverse direction X and then contracting it in the longitudinal direction Y with the longitudinal contraction type second transverse stretching machine 110, The product film 5b sent out from the contraction-type second transverse stretching machine 110 can be immediately wound up by the winding machine 111, or other work can be performed on the product film 5b. As a result, it is possible to more reliably suppress the increase in manufacturing time and prevent wrinkles from occurring.

Further, when the product film 5b has a large vertical heat shrinkage ratio, if it is wound by the winder 111 without performing aging, wrinkles or folds may occur due to winding tightness due to the heat shrinkage of the product film 5b in the vertical direction. There is. Therefore, in order to suppress winding tightness, it is necessary to wind with a low tension, and winding misalignment due to winding with a low tension occurs, or a soft sponge was wound to achieve a low tension winding. It is necessary to use a special winding core. On the other hand, when the longitudinal heat shrinkage of the product film 5b is reduced by shrinking the raw film 5a in the longitudinal direction Y, winding tightness occurs even if the product film 5b is wound by the winder 111 without performing aging. It is possible to prevent the occurrence of wrinkles and breaks due to winding tightness. As a result, the ease and quality of manufacture of the product film 5b can be improved.

In addition, the vertical contraction type second horizontal stretching machine 110 connects the adjusting rails 27b provided for adjusting the distance between the clips 18 and the adjacent clips 18 and abuts the adjusting rails 27b so that the distance between the clips 18 is increased. Since it has a space adjusting mechanism 19 for adjusting, the space between the adjacent clips 18 can be easily adjusted by adjusting the position of the adjusting rail 27b. Accordingly, the original film 5a held by the clip 18 can be easily contracted in the longitudinal direction Y, and residual stress in the longitudinal direction Y of the original film 5a is removed, whereby the longitudinal direction Y of the product film 5b can be reduced. Thermal contraction can be easily suppressed. As a result, it is possible to more easily reduce the longitudinal heat shrinkage of the separator film while suppressing the increase in the manufacturing time and the complexity of the apparatus configuration.

Further, in the range where the original film 5a is contracted in the vertical direction Y, the interval between the clips 18 is contracted in the vertical direction Y, so that the contraction rate in the vertical direction Y is 6% or more and 20% or less. Since the film 5a is shrunk in the vertical direction Y, the thermal shrinkage of the product film 5b in the vertical direction Y can be more reliably suppressed. That is, when the shrinkage rate of the original film 5a in the vertical direction Y is less than 6%, the shrinkage rate in the vertical direction Y is too small, and therefore the residual stress in the vertical direction Y of the product film 5b is effectively removed. May become difficult, and it may become difficult to suppress thermal contraction in the vertical direction Y. When the shrinkage rate of the raw film 5a in the longitudinal direction Y is larger than 20%, the shrinkage rate in the vertical direction Y is too large, so that the transported raw film 5a may be easily loosened.

On the other hand, when the shrinkage rate in the longitudinal direction Y during transport of the raw film 5a is shrunk in the vertical direction Y within the range of 6% or more and 20% or less, while suppressing the looseness of the raw film 5a, The residual stress in the vertical direction Y of the product film 5b can be effectively removed. As a result, it is possible to suppress the occurrence of slack in the original film 5a and improve the quality of the product film 5b, and it is possible to more reliably suppress the heat shrinkage of the product film 5b in the longitudinal direction Y. As a result, the longitudinal heat shrinkage rate of the separator film can be reduced more reliably.

[Embodiment 2]
The separator film manufacturing apparatus 100 according to the second embodiment has substantially the same configuration as the separator film manufacturing apparatus 100 according to the first embodiment, but includes a second horizontal stretching machine 115, and also has a longitudinal contraction type second horizontal stretching machine. It is characterized in that 110 is used as the vertical contraction type third transverse stretching machine 120. Since the second transverse stretching machine 115 in the preceding stage performs the transverse stretching, the longitudinal contraction-type third transverse stretching machine 120 does not perform the transverse stretching but performs the treatment while contracting in the longitudinal and lateral directions. Since the configuration is the same as that of the first embodiment, the description thereof will be omitted and the same reference numerals will be given.

<Configuration of separator film manufacturing apparatus 100>
FIG. 7 is a block diagram showing an apparatus configuration of the separator film manufacturing apparatus 100 according to the second embodiment. The separator film manufacturing apparatus 100 according to the second embodiment, like the separator film manufacturing apparatus 100 according to the first embodiment, is mainly used for manufacturing a separator film used in a lithium ion battery. The separator film manufacturing apparatus 100 according to the second embodiment is similar to the separator film manufacturing apparatus 100 according to the first embodiment in that the raw material supply device 101, the extruder 102, the T die 103, the casting machine 104, and the longitudinal stretching machine. 105, a first transverse stretching machine 106, an extraction/drying device 107, and a winding machine 111.

Furthermore, the separator film manufacturing apparatus 100 according to the second embodiment is configured such that the raw film 5a from which the liquid plasticizer has been extracted by the extraction/drying device 107 is conveyed in the vertical direction, while the raw film 5a is stretched in the horizontal direction. The stretching machine 115 and the longitudinal contraction type third lateral stretching machine 120 are provided. Of these, the vertical shrinkage type third horizontal stretching machine 120 has the same configuration as the vertical shrinkage type second horizontal stretching machine 110 included in the separator film manufacturing apparatus 100 according to the first embodiment, and is upstream of the winder 111. It is located on the side. Further, the second transverse stretching machine 115 receives the raw fabric film 5 a from the extraction drying device 107, and conveys the raw fabric film 5 a stretched in the transverse direction by the second transverse stretching machine 115 to the vertical contraction type third transverse stretching machine 120. It is placed in a position where you can. That is, the second transverse stretching machine 115 is arranged between the extraction/drying device 107 and the longitudinal contraction type third transverse stretching machine 120 in the transport path of the original film 5a.

The second transverse stretching machine 115 thus arranged has the same configuration as the first transverse stretching machine 106, and grips both ends in the transverse direction of the raw film 5a conveyed from the extraction/drying device 107, The anti-film 5a is stretched in the transverse direction while being conveyed in the longitudinal direction. As a result, the second transverse stretching machine 115 adjusts the size of the fine holes formed in the original film 5a. The raw film 5a stretched in the transverse direction by the second transverse stretching machine 115 is conveyed from the second transverse stretching machine 115 to the longitudinal shrinkable third transverse stretching machine 120.

The vertical shrinkage type third horizontal stretching machine 120 included in the separator film manufacturing apparatus 100 according to the second embodiment has the same configuration as the vertical shrinkage type second horizontal stretching machine 110 included in the separator film manufacturing apparatus 100 according to the first embodiment. ing. Therefore, the vertical contraction-type third horizontal stretching machine 120 reduces the distance between the clips 18 in the horizontal direction X and the distance between the longitudinal directions Y of the raw film 5a stretched in the horizontal direction by the second horizontal stretching machine 115. Thus, the original film 5a can be contracted in the horizontal direction X and the vertical direction Y. That is, the vertical shrinkage-type third horizontal stretching machine 120 stretches the raw film 5a in the horizontal direction X while conveying the raw film 5a in the vertical direction Y, similarly to the vertical shrinkage-type second horizontal stretching machine 110 of the first embodiment. It is provided as a vertical shrinkage type heat treatment device capable of shrinking the transported original film 5a in the vertical direction Y.

The product film 5b, which is a film obtained by shrinking the original film 5a in the horizontal direction X and the vertical direction Y by the vertical shrinkage type third horizontal stretching machine 120, is sent out from the vertical shrinkage type third horizontal stretching machine 120 and is wound by the winder 111. And is wound into a roll by the winder 111.

<Effect of Embodiment 2>
Also in the separator film manufacturing apparatus 100 according to the second embodiment, the vertical shrinkage type third transverse stretching machine 120, which is a vertical shrinkage type heat treatment apparatus, generates residual stress by stretching in the transverse direction X by the second transverse stretching machine 115. The residual stress in the vertical direction Y of the original film 5a can be removed by the contraction of the original film 5a in the vertical direction Y. Thereby, the heat shrinkage of the product film 5b in the longitudinal direction Y can be suppressed, and after the raw film 5a is stretched in the transverse direction X by the second transverse stretching machine 115, the raw film 5a is exposed at a high temperature. The longitudinal thermal shrinkage of the product film 5b can be reduced without lengthening the time or performing roll annealing or aging. Therefore, even in the existing separator film manufacturing apparatus 100 including the second transverse stretching machine 115, the longitudinal thermal shrinkage rate of the product film 5b can be reduced only by adding the longitudinal shrinkage type third lateral stretching machine 120. As a result, even in the existing separator film manufacturing apparatus 100, it is possible to easily reduce the longitudinal heat shrinkage rate of the separator film while suppressing the increase in manufacturing time and the complexity of the apparatus configuration.

[Modification]
In the separator film manufacturing apparatus 100 according to

Embodiments

1 and 2 described above, in the step of stretching the sheet cooled and solidified by the casting machine 104 between the casting machine 104 and the extraction drying apparatus 107, the longitudinal stretching machine 105. However, the step of stretching the sheet to form a film may be performed by one apparatus. That is, in the separator film manufacturing apparatus 100 according to the first and second embodiments, in the step of stretching the sheet between the casting machine 104 and the extraction/drying apparatus 107, longitudinal stretching and transverse stretching are sequentially performed. Although biaxial stretching is carried out, longitudinal bidirectional stretching and transverse stretching may be carried out simultaneously, or simultaneous biaxial stretching may be carried out. In this case, between the casting machine 104 and the extraction/drying apparatus 107, in place of the longitudinal stretching machine 105 and the first transverse stretching machine 106, it is possible to simultaneously perform longitudinal stretching and transverse stretching of the sheet. Yes, a simultaneous biaxial stretching machine is placed. After extracting the liquid plasticizer from the raw fabric film 5a and drying the raw fabric film 5a, if the raw fabric film 5a can be contracted in the longitudinal direction Y, the method of stretching the sheet in the preceding step The stretching in the direction and the stretching in the transverse direction may be performed sequentially or simultaneously, or either.

Further, in the separator film manufacturing apparatus 100 according to the first and second embodiments according to the above-described embodiments, T1 to T10 are used as the heat-retaining greenhouses for the vertical shrinkage type second horizontal stretching machine 110 and the vertical shrinkage type third horizontal stretching machine 120. Although it is set, it is preferable to appropriately set the heat-retaining greenhouse according to the specifications of the raw film 5a.

Further, in the separator film manufacturing apparatus 100 according to the first and second embodiments according to the above-described embodiment, the vertical contraction type second horizontal stretching machine 110 and the vertical contraction type third horizontal stretching machine 120 have the return rail unit 11 of the oven 30. Although it is configured as a so-called inside return type installed inside, in the vertical contraction type second horizontal stretching machine 110 and the vertical contraction type third horizontal stretching machine 120, the return rail unit 11 is installed outside the oven 30. It may be configured as a so-called outside return type.

<Test for manufacturing method of separator film>
The inventors conducted a test for the shrinkage rate during transport of the raw film 5a, which can reduce the longitudinal heat shrinkage rate of the separator film. Next, an evaluation test on the relationship between the longitudinal shrinkage rate of the original film 5a during transportation and the thermal shrinkage rate of the product film 5b after transportation will be described. The longitudinal shrinkage here refers to the original film 5a immediately before being conveyed by the second longitudinal contraction type horizontal stretching machine 110 or the third vertical contraction type horizontal stretching machine 120, or the original film 5a at the start of conveyance. The contraction rate is in the vertical direction Y, and is substantially the contraction rate of the interval between the clips 18 that hold the original film 5a.

FIG. 8 is an explanatory diagram showing the relationship between the shrinkage rate of the original film 5a during transportation and the thermal shrinkage rate of the product film 5b after transportation. FIG. 9 is a graph of the test results shown in FIG. The test on the relationship between the longitudinal shrinkage rate of the original film 5a during transportation and the thermal shrinkage rate of the product film 5b after transportation is carried out by the vertical shrinkage type second oven 30 having seven heating-retaining greenhouses T1 to T7. The transverse stretching machine 110 was used. The heated greenhouses are arranged in order from T1 to T7 with T1 being located closest to the inlet sprocket 6 side and T7 being located closest to the outlet sprocket 7. In this test, the temperature of each heat-retaining greenhouse is 126° C., the raw film 5a is conveyed at a conveying speed of 50 m/min, and the product film 5b after conveyance is left in an atmosphere of 120° C. for 1 hour to shrink. The rate was measured as the heat shrinkage rate. The heat shrinkage in this case is the shrinkage of the product film 5b immediately after being conveyed, and the heat shrinkage in the vertical direction Y and the heat shrinkage in the horizontal direction X were measured.

In the test on the relationship between the longitudinal shrinkage rate of the raw film 5a during transportation and the thermal shrinkage rate of the product film 5b after transportation, as shown in FIG. The test was conducted with five different types of longitudinal shrinkage. That is, the test No. In No. 1, the longitudinal shrinkage rate is 0% in the entire range of the heating greenhouses T1 to T7. In addition, the test No. In No. 2, the vertical shrinkage in the heat-retaining greenhouses T1 to T3 is 0%, the vertical shrinkage in the heat-retaining greenhouse T4 is 2.5%, and the vertical shrinkage in the heat-retaining greenhouses T5 to T7 is 5%. There is. In addition, the test No. In No. 3, the vertical shrinkage rate in the heat-retaining greenhouses T1 to T3 is 0%, the vertical shrinkage rate in the heat-retaining greenhouse T4 is 3.8%, and the vertical shrinkage rate in the heat-retaining greenhouses T5 to T7 is 7.5%. %. In addition, the test No. In No. 4, the vertical shrinkage rate in the heat-retaining greenhouses T1 to T3 is 0%, the vertical shrinkage rate in the heat-retaining greenhouse T4 is 5%, and the vertical shrinkage rate in the heat-retaining greenhouses T5 to T7 is 10%. In addition, the test No. In No. 5, the vertical shrinkage rate in the heat-retaining greenhouses T1 to T3 is 0%, the vertical shrinkage rate in the heat-retaining greenhouse T4 is 6%, and the vertical shrinkage rate in the heat-retaining greenhouses T5 to T7 is 12%.

In this way, the test on the relationship between the longitudinal shrinkage rate of the original film 5a during transportation and the thermal shrinkage rate of the product film 5b after transportation was performed, and as a result, as shown in FIGS. It was confirmed that when the final longitudinal shrinkage of the anti-film 5a exceeds 5%, the thermal shrinkage of the product film 5b in the longitudinal direction Y and the lateral direction X after being conveyed is effectively reduced. .. That is, in this test, the heat shrinkage rate of the product film 5b is appropriately reduced by transporting the raw film 5a in the vertical direction Y and shrinking the raw film 5a in the vertical direction Y within the range of 6% or more and 20% or less. It was confirmed that

1L... left moving path, 1R... right moving path, 1A... transport area, 2... forward path, 3... return path, 4L... left rail structure, 4R... right rail structure, 5a... original film, 5b... product film, 6... Entrance side sprocket, 7... Exit side sprocket, 8, 9... Clip chain, 10... Forward rail unit, 11... Return rail unit, 12... Rail block, 13... Forward block, 14... Return block, 18... Clip, 19... Interval adjusting mechanism, 20... Moving mechanism, 27... Rail moving mechanism, 30... Oven, 40L... Left gripping device, 40R... Right gripping device, 100... Separator film manufacturing device, 101... Raw material supply device, 102... Extruder , 103... T-die, 104... Casting machine, 105... Longitudinal stretching machine, 106... First transverse stretching machine, 107... Extraction drying apparatus, 108... Extraction apparatus, 109... Drying apparatus, 110... Vertical contraction type second transverse stretching Machine (longitudinal shrinkage type heat treatment device), 111...winding machine, 115...second transverse stretching machine, 120...longitudinal shrinkage type third transverse stretching machine (longitudinal shrinkage type heat treatment device)

Claims

Extraction to extract the liquid plasticizer from the raw film made into a porous film by performing longitudinal stretching and transverse stretching on the sheet obtained by molding after melt-kneading the polyolefin resin and the liquid plasticizer A device,
A clip chain having a plurality of clips for holding the original film is provided, and the original film is stretched in the horizontal direction while the original film is conveyed in the longitudinal direction by running the clip chain, and the clip is A vertical shrinkage type heat treatment apparatus capable of shrinking the original film in the vertical direction by adjusting the interval of
An apparatus for producing a separator film, comprising:
The vertical shrinkage type heat treatment device,
An adjustment rail arranged to adjust the distance between the clips,
An interval adjusting mechanism that connects the clips adjacent to each other among the plurality of clips and abuts on the adjusting rail to adjust the interval between the clips.
The separator film manufacturing apparatus according to claim 1, further comprising:
A second transverse stretching machine for stretching the raw fabric film in the transverse direction while conveying the raw fabric film in which the liquid plasticizer is extracted in the extraction device in the longitudinal direction,
The separator film manufacturing apparatus according to claim 1 or 2, wherein the longitudinal shrinkage type heat treatment device is capable of shrinking the original film stretched in the transverse direction by the second transverse stretching machine in the longitudinal direction.
4. The longitudinal shrinkage type heat treatment apparatus shrinks the raw fabric film in the lateral direction by stretching the raw fabric film in the lateral direction and then reducing the interval between the clips in the lateral direction. The separator film manufacturing apparatus as described in 1 above.
A step of extracting the liquid plasticizer from a raw film formed into a porous film by performing longitudinal stretching and transverse stretching on a sheet obtained by molding a polyolefin resin and a liquid plasticizer after melt-kneading When,
While stretching the raw fabric film in the transverse direction while conveying the raw fabric film that has extracted the liquid plasticizer in the longitudinal direction, a step of shrinking the raw fabric film in the longitudinal direction,
A method for producing a separator film containing:
The method for producing a separator film according to claim 5, wherein after the raw film is stretched in the lateral direction, the raw film is contracted in the lateral direction.
The method for producing a separator film according to claim 5 or 6, wherein the original film is shrunk in the machine direction in the range of 6% to 20% in the machine direction.