WO2017111048A1

WO2017111048A1 - Film manufacturing method and film

Info

Publication number: WO2017111048A1
Application number: PCT/JP2016/088421
Authority: WO
Inventors: 慶栄董
Original assignee: 住友化学株式会社
Priority date: 2015-12-25
Filing date: 2016-12-22
Publication date: 2017-06-29
Also published as: JPWO2017111048A1; CN108474890A; JP6342081B2; KR101907336B1; CN108474890B; KR20170118961A

Abstract

This film manufacturing method includes a sheet film acquisition step for acquiring a sheet film, which is a sheet-shaped resin film, from a long strip-shaped resin film, and an end-face-machining step for machining the end face of the film to obtain an end-face-machined film following the sheet film acquisition step, wherein the film manufacturing method furthermore includes an environment adjustment step for providing an unattended environment for leaving the sheet film unattended in which the atmosphere has been at least adjusted for humidity.

Description

Film manufacturing method and film

The present invention relates to a film manufacturing method and a film.
This application claims priority based on Japanese Patent Application No. 2015-254899 filed in Japan on December 25, 2015, the contents of which are incorporated herein by reference.

Conventionally, as a film manufacturing method, for example, there is one disclosed in Patent Document 1. This relates to a method of cutting out a sheet-like optical film chip from a long belt-like optical film.
For example, the optical film chip is cut to a size that matches the display area of the liquid crystal panel and then bonded to the liquid crystal panel.

JP 2003-255132 A

By the way, the optical film chip is rarely attached to the liquid crystal panel immediately after being cut out, and is often left until it is attached to the liquid crystal panel. The optical film chip expands and contracts depending on the humidity level of the leaving environment. Therefore, even if the optical film chip is cut out to a size that matches the display area of the liquid crystal panel, the size of the optical film chip may change when the optical film chip is subsequently bonded to the liquid crystal panel. For this reason, it may be difficult to attach the optical film chip to the display area of the liquid crystal panel with high accuracy. On the other hand, recently, display devices have become framed, and stricter dimensional accuracy than ever is required for optical film chips. For example, the conventional dimensional tolerance is about ± 100 to 150 μm, but recently a dimensional tolerance of about ± 30 to 50 μm is required. In the future, the required accuracy will become stricter, and it is expected that the optical film chip obtained by the conventional manufacturing method will not be able to cope with it.

The present invention has been made in view of the above circumstances, and provides a film manufacturing method capable of improving the dimensional accuracy of a film and a film having improved dimensional accuracy.

In order to achieve the above object, the present invention employs the following means.
(1) A film manufacturing method according to one aspect of the present invention includes a sheet-fed film acquisition step of acquiring a sheet-fed film that is a sheet-fed resin film from a long strip-shaped resin film, and the sheet-fed film acquisition step. And an end face processing step for obtaining an end face processed film by processing an end face of the single wafer film, wherein the single wafer is between the single film acquisition step and the end face processing step. It further includes an environment adjustment step in which the leaving environment in which the film is left is at least an atmosphere in which the humidity is adjusted.

(2) In the film manufacturing method of (1), in the environment adjustment step, the humidity and temperature of the leaving environment are ± 5 relative to the humidity and temperature at which the end face processed film is used after the end face processing step. % And ± 5 ° C.

(3) In the film manufacturing method according to (1) or (2) above, in the environment adjustment step, the dimensional change per unit time of the single-wafer film converges in the time for which the single-wafer film is left in the leaving environment. More than the time approaching.

(4) In the film manufacturing method according to (3), in the environment adjustment step, the time for leaving the sheet film in the leaving environment is set to a dimensional change rate per unit time of 0.003%. The time is equal to or less than / hour.

(5) In the film manufacturing method according to (3) or (4) above, in the environmental adjustment step, the time for leaving the sheet film in the leaving environment is set to 6 hours or more.

(6) In any one of the above-described film manufacturing methods (1) to (5), in the environmental adjustment step, the single-wafer film is left with the main surface of the single-wafer film along the vertical direction.

(7) In the film manufacturing method according to any one of (1) to (6), the sheet film is rectangular, and in the environment adjustment step, an end surface along the long side of the sheet film is used. The sheet film is left exposed.

(8) In any one of the above-described film manufacturing methods (1) to (7), in the environment adjustment step, the laminate is left as a laminate in which a plurality of the single-wafer films are stacked.

(9) In the film manufacturing method of (8), in the environmental adjustment step, a dummy film is provided on the main surface side of the laminate, and the laminate is left unattended.

(10) In the film manufacturing method according to any one of (1) to (9), the end face of the single wafer film is polished in the end face processing step.

(11) In any one of the film production methods (1) to (10), the resin film is an optical film.

(12) The film according to one aspect of the present invention has a rectangular shape, and when held for 24 hours in an environment of humidity of 52% and temperature of 23 ° C., the dimensional change rate of the two long sides is Is less than 0.0002% / hour.

According to the present invention, a film manufacturing method capable of improving the dimensional accuracy of a film and a film having improved dimensional accuracy can be provided.

It is a top view which shows an example of a liquid crystal display panel. FIG. 2 is a sectional view taken along the line II-II in FIG. It is sectional drawing which shows an example of an optical film. It is a perspective view which shows the film manufacturing method which concerns on embodiment. It is a flowchart of the film manufacturing method which concerns on embodiment. It is a perspective view which shows the example of the leaving state of the sheet | seat film which concerns on embodiment. It is a perspective view which shows the other example of the leaving state of the sheet | seat film which concerns on embodiment. It is a perspective view which shows the modification of the leaving state of a sheet | seat film. It is a perspective view which shows the other modification of the leaving state of a sheet | seat film. It is a graph for demonstrating the dimensional change amount of the long side of the film in an Example. It is a graph for demonstrating the dimensional change amount of the short side of the film in an Example. It is a figure for demonstrating the leaving state of the film in an Example. It is a graph for demonstrating the dimensional change amount of the 1st long side of the film in an Example. It is a graph for demonstrating the dimensional change amount of the 2nd long side of the film in an Example. It is a graph for demonstrating the dimensional change amount of the 1st short side of the film in an Example. It is a graph for demonstrating the dimensional change amount of the 2nd short side of the film in an Example. It is a graph which shows the dimensional change amount of the 1st long side of the film in an Example and a comparative example. It is a graph which shows the dimensional change amount of the 2nd long side of the film in an Example and a comparative example. It is a graph which shows the dimensional change amount of the 1st short side of the film in an Example and a comparative example. It is a graph which shows the dimensional change amount of the 2nd short side of the film in an Example and a comparative example.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In the present embodiment, a film manufacturing method using an optical film as a resin film will be described.

For example, examples of the optical film include a polarizing film, a retardation film, and a brightness enhancement film. For example, the optical film is used by being bonded to a panel-like optical display component (optical display panel) such as a liquid crystal display panel or an organic EL display panel.

In this embodiment, a transmissive liquid crystal display device (not shown) will be described as an example of an optical display device. The transmissive liquid crystal display device includes a liquid crystal display panel and a backlight. In this liquid crystal display device, illumination light emitted from the backlight is incident from the back side of the liquid crystal display panel, and light modulated by the liquid crystal display panel is emitted from the front side of the liquid crystal display panel, thereby displaying an image. It is possible.

(Optical display device)
First, the configuration of the liquid crystal display panel P shown in FIGS. 1 and 2 will be described as an optical display device. FIG. 1 is a plan view showing an example of the liquid crystal display panel P. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. In FIG. 2, hatching showing a cross section is omitted.

As shown in FIGS. 1 and 2, the liquid crystal display panel P includes a first substrate P1, a second substrate P2 disposed opposite to the first substrate P1, a first substrate P1, and a second substrate P1. And a liquid crystal layer P3 arranged between the substrate P2.

The first substrate P1 is made of a transparent substrate having a rectangular shape in plan view. The second substrate P2 is a transparent substrate having a rectangular shape that is relatively smaller than the first substrate P1. The liquid crystal layer P3 seals the periphery between the first substrate P1 and the second substrate P2 with a sealing material (not shown), and is located inside a rectangular region in plan view surrounded by the sealing material. Is arranged. In the liquid crystal display panel P, an area that fits inside the outer periphery of the liquid crystal layer P3 in plan view is a display area P4, and an outer area that surrounds the display area P4 is a frame portion G.

On the back surface (backlight side) of the liquid crystal display panel P, there are a first optical film F11 as a polarizing film and a third optical film F13 used as a brightness enhancement film on the first optical film F11. They are laminated and bonded in order. On the surface (display surface side) of the liquid crystal display panel P, a second optical film F12 as a polarizing film is bonded. Hereinafter, the first, second, and third optical films F11, F12, and F13 may be collectively referred to as an optical film F1X.

(Optical film)
Next, an example of the optical sheet FX constituting the optical film F1X shown in FIG. 3 will be described. FIG. 3 is a cross-sectional view illustrating a configuration of the optical sheet FX. In FIG. 3, hatching showing a cross section is omitted.

The optical film F1X is obtained by cutting a sheet piece having a predetermined length from the long belt-like optical sheet FX shown in FIG. Specifically, the optical sheet FX includes a base material sheet F4, an adhesive layer F5 provided on one surface (upper surface in FIG. 3) of the base material sheet F4, and a base material sheet via the adhesive layer F5. It has a separator sheet F6 provided on one surface of F4 and a surface protection sheet F7 provided on the other surface (lower surface in FIG. 3) of the base material sheet F4.

In the case of a polarizing film, for example, the base sheet F4 has a structure in which a polarizer F4a is sandwiched between a pair of protective films F4b and F4c.
The adhesive layer F5 adheres the base material sheet F4 to the liquid crystal display panel P.
Separator sheet F6 protects adhesive layer F5. The adhesive layer F5 is exposed by peeling and removing the separator sheet F6 from the optical film F1X. Thereafter, the optical film F1X is bonded to the liquid crystal display panel P. In addition, the part (part used as the optical film F1X) remove | excluding the separator sheet F6 from the optical film F1X is set as the bonding sheet | seat F8.
The surface protection sheet F7 protects the surface of the base material sheet F4. The surface protective sheet F7 is peeled off from the surface of the base sheet F4 after the base sheet F4 is attached to the liquid crystal display panel P.

In addition, about the base material sheet F4, you may abbreviate | omit any one of a pair of protective films F4b and F4c. For example, the protective film F4b on the adhesive layer F5 side may be omitted, and the adhesive layer F5 may be provided directly on the surface of the polarizer F4a. The protective film F4c on the surface protective sheet F7 side may be subjected to a surface treatment such as a hard coat treatment for protecting the outermost surface of the liquid crystal display panel P or an antiglare treatment for obtaining an antiglare effect. . Moreover, about the base material sheet F4, not only the laminated structure mentioned above but a single layer structure may be sufficient. In the optical film F1X described in the present embodiment, the surface protection sheet F7 may be omitted.

(Film production method)
Next, the film manufacturing method according to the present embodiment will be described. FIG. 4 is a perspective view showing the film manufacturing method according to the present embodiment. FIG. 5 is a flowchart of the film manufacturing method according to this embodiment.

For example, the film manufacturing method according to the present embodiment is a method of manufacturing an optical film F10X in which a surface protective film is bonded to both surfaces of a polarizing film. This film manufacturing method may include a manufacturing process of the optical film F10X. Moreover, for example, the film manufacturing method according to the present embodiment includes an original roll manufacturing process for manufacturing an original roll (not shown) of a long strip-shaped polarizing film, and a long strip-shaped surface on the long strip-shaped polarizing film. A pasting step in which a protective film is pasted to manufacture an original fabric roll R1 of the long belt-shaped optical film F10X.

For example, in the above-mentioned raw roll manufacturing process, a film that has been subjected to the above-mentioned treatment after being subjected to a dyeing treatment, a crosslinking treatment, a stretching treatment, etc. on a film that is a base material for a polarizer such as PVA (Polyvinyl Alcohol) A protective film such as TAC (Triacetylcellulose) is pasted on both sides of the film to produce a long band-shaped polarizing film, and the resulting polarizing film is wound around a core material to obtain an original roll (not shown) .

In the laminating step, the long strip-shaped polarizing film and the long strip-shaped surface protective film are obtained from the long strip-shaped polarizing film original roll and the long strip-shaped surface protective film original roll (not shown). While unwinding each, these are pinched | interposed with a nip roll etc., are bonded, and are drawn out, and produce the elongate optical film F10X. And the original fabric roll R1 is obtained by winding up manufactured optical film F10X to a core material. For example, PET (Polyethylene terephthalate) is used as the surface protective film.

As shown in FIG.4 and FIG.5, the film manufacturing method of this embodiment is a sheet | seat film acquisition process (in FIG. 5) which acquires the sheet | seat film 11 which is a sheet-like optical film from the elongate strip-shaped optical film F10X. Step S1) shown, an environment adjustment step (step S2 shown in FIG. 5) in which the leaving environment in which the sheet film 11 is left after the sheet-fed film acquisition step is at least a humidity-adjusted atmosphere, and an environment adjustment step After that, it further includes an end face processing step (step S3 shown in FIG. 5) of polishing (processing) the end face of the sheet film 11 to obtain the end face processed film 11A.

(Single wafer film acquisition process)
As shown in FIG. 4, in the single-wafer film acquisition step, a plurality of rectangular single-wafer films 11 are cut out from the long belt-like optical film F 10 X using a cutting device not shown in FIG. 4. As said cutting device, for example, a plurality of cutters arranged at intervals corresponding to the length of the long side of the sheet film 11, and a plurality of cutters arranged at intervals corresponding to the length of the short side of the sheet film 11 Can be used that are arranged in a grid pattern in a plan view. In this cutting apparatus, a region cut out in a rectangular shape by four cutters is a cut-out region of one single sheet film 11. In addition, you may use a laser cutter as a cutting device.

In addition, in FIG. 4, although the example which cuts out the rectangular sheet | seat film 11 from the elongate optical film F10X was shown, it does not restrict to this. Various shapes can be adopted as the shape of the sheet film 11 to be cut out. For example, the shape of the sheet film 11 may be a polygonal shape such as a square, rhombus, hexagon, or octagon, or a shape having a curve such as a circle or an ellipse, The shape may have a curved edge and a straight edge.

(Environmental adjustment process)
In the environment adjustment process, the humidity and temperature of the leaving environment are adjusted to an environment close to the humidity and temperature (target value) at which the end face processed film 11A is used after the end face processing process. For example, in the environmental adjustment step, the humidity and temperature of the leaving environment are substantially the same as the humidity and temperature when the end face processed film 11A is bonded to the liquid crystal display panel P (see FIG. 2) as the optical film F1X (see FIG. 3). Are the same. For example, the humidity and temperature of the leaving environment are preferably in the range of ± 5% and ± 5 ° C. with respect to the target value, and more preferably in the range of ± 3% and ± 3 ° C. with respect to the target value. In the present embodiment, an example in which the single wafer film 11 is moistened (absorbed) in the environment adjustment process will be described. Here, “humidity” described in the present specification refers to relative humidity, which is the ratio of the actual water vapor pressure to the saturated water vapor pressure at room temperature.

For example, the neglected environment in the environment adjustment process is set inside the storage chamber 15 in which a plurality of single-wafer films 11 can be stored. In addition, the leaving environment in an environmental adjustment process may be the same as the usage environment of the cutting device in a sheet-fed film acquisition process. That is, the leaving of the sheet film 11 in the environment adjustment process may be performed in the same environment as the sheet film acquisition process.

The accommodation room 15 is configured such that the humidity and temperature inside the accommodation room 15 can be adjusted. The storage chamber 15 is provided with a humidity adjusting device and a temperature adjusting device (not shown). For example, as the storage room 15, a clean room that can keep the inside of the storage room 15 clean can be used.

Generally, the clean room is used when the single wafer film 11 is an optical film such as a polarizing film. In order to more effectively exhibit the effects of the present invention, it is more preferable that the environment of the accommodation room 15 is brought closer (matched) with the environment of the clean room. Usually, the clean room environment has a humidity of 47% to 57% and a temperature of 18 ° C to 28 ° C.

Next, the leaving state of the single wafer film 11 according to this embodiment will be described. FIG. 6 is a perspective view showing an example of the leaving state of the sheet film 11 according to the present embodiment. FIG. 7 is a perspective view showing another example of the leaving state of the sheet film 11 according to the present embodiment.

As shown in FIG.6 and FIG.7, in the environmental adjustment process, the main surface 11a of the sheet | seat film 11 is made to follow the vertical direction V1. In the environment adjustment step, the end face 11e along the long side of the sheet film 11 is exposed and the sheet film 11 is left unattended.
In addition, the “main surface 11 a of the sheet film 11” described in the present specification is any one of both surfaces of the sheet film 11.

In FIG. 6, the film stand 20 which can stand the sheet | seat film 11 piece by piece is illustrated.
As shown in FIG. 6, the film stand 20 is connected to a rectangular plate-like bottom plate portion 21 having a longitudinal direction in the arrangement direction of the sheet films 11 and one end portion of the bottom plate portion 21 and along the vertical direction V 1. Connected to the bottom surface of the rectangular plate-like side wall portion 22 standing in the direction and having the longitudinal direction in the arrangement direction of the sheet films 11 and the other end portion of the bottom plate portion 21 (the end portion opposite to the side wall portion 22) A rectangular columnar bottom support portion 23 having a longitudinal direction in the arrangement direction of the sheet film 11, and a rectangular frame shape that is connected to the bottom plate portion 21 and the side wall portion 22 and smaller than the sheet film 11, and A partition frame 24 arranged at intervals in the arrangement direction of the sheet films 11.

In the film stand 20, a single sheet film 11 is disposed between two adjacent partition frames 24 so as to lean on the partition frame 24. The interval between two adjacent partition frames 24 is sufficiently larger than the thickness of the sheet film 11. The main surface 11 a of the sheet film 11 is exposed from the opening 24 h of the partition frame 24.
Moreover, in the film standing base 20, the end surface 11e along the long side on the opposite side to the baseplate part 21 of the sheet | seat film 11 and the short side on the opposite side to the side wall part 22 of the sheet | seat film 11 is exposed. It is configured. Thereby, since the sheet | seat film 11 can be exposed as much as possible, the sheet | seat film 11 can fully be wetted in an environmental adjustment process.
In addition, from the viewpoint of sufficiently wetting the sheet film 11 in the environmental adjustment step, it is more preferable to leave the end face 11e along the two long sides of the sheet film 11 exposed.

In the film stand 20, the end portion of the single-wafer film 11 on the side of the bottom support portion 23 protrudes to the side of the bottom support portion 23. Further, the film stand 20 is inclined so as to be positioned higher toward the bottom support portion 23 side. Thereby, since the operation | work which leans the sheet | seat film 11 on the film stand 20 or takes out from the film stand 20 becomes easy, workability | operativity can be improved.

In FIG. 7, the film support stand 30 which can support the laminated body 12 which piled up the sheet | seat film 11 in multiple numbers is illustrated.
As shown in FIG. 7, the film support 30 is connected to the rectangular plate-shaped base 31 and the upper surface of the base 31, and stands in the direction along the vertical direction V 1, and the thickness direction of the stacked body 12. And prismatic support pillars 32 arranged at intervals (in the arrangement direction of the sheet films 11). The support pillars 32 are provided as a pair so as to sandwich the laminate 12 in the thickness direction of the laminate 12. A plurality of (for example, two sets in FIG. 7 referred to in the present embodiment) a plurality of pairs of support pillars 32 are arranged in the longitudinal direction of the laminated body 12 (longitudinal direction of the sheet film 11).

A dummy film 13 is provided on the main surface side of the laminate 12 (side adjacent to the pair of support columns 32). The dummy film 13 is a film that is not used as a product. In the present embodiment, the sheet film 11 is also used as the dummy film 13. For example, when 100 sheet films 11 are stacked to form a laminated body 12, the first sheet film 11 and the 100th sheet film 11 are the dummy films 13.

In the film support base 30, the distance between the pair of support columns 32 (two support columns 32 adjacent to each other in the thickness direction of the stacked body 12) is such that the thickness of the stacked body 12 can be maintained. Is slightly larger than. In the laminated body 12, the main surface 11 a of the sheet film 11 is exposed from between two adjacent sheet films 11. Further, in the film support base 30, from between the pair of support pillars 32, there are end faces 11 e along the long side opposite to the base 31 of the sheet film 11 in the laminate 12 and the short side of the sheet film 11. It is supposed to be exposed. Thereby, since the sheet | seat film 11 can be exposed and left as much as possible, the sheet | seat film 11 can fully be wetted in an environmental adjustment process.

In the film support table 30, the distance between the pair of support columns 32 is large so that a sufficiently thick laminate 13 (a sufficient number of sheet films 11) can be disposed. As a result, a sufficient number of sheet films 11 can be collectively supported on the film support table 30 and taken out from the film support table 30, so that workability can be improved.

In addition, in the laminated body 12, the number of stacked sheets 11 can be arbitrarily set in consideration of the thickness of the sheets 11 and the like. For example, the number of stacked sheets 11 is preferably 50 or more and 300 or less in consideration of handling in a later process.

In the environmental adjustment process, the following effects are achieved by leaving the laminated film 11 as a laminated body 12 in which a plurality of sheet films 11 are stacked. First, the end face processing of the single wafer film 11 can be efficiently performed after the environmental adjustment process. Moreover, the dimensional change and curl change of the end face processed film 11A can be effectively suppressed.

Next, the time for leaving the sheet film 11 in the leaving environment in the environment adjusting step will be described.
In the environment adjustment step, the time for which the sheet film 11 is left in the leaving environment (hereinafter referred to as “leaving time”) is set to be longer than the time when the dimensional change per unit time of the sheet film 11 approaches convergence. Here, the “time when the dimensional change per unit time of the sheet film approaches convergence” described in the present embodiment is specifically the following time.
For example, in the environment adjustment process, the standing time can be set to be equal to or longer than the time when the dimensional change rate per unit time of the sheet film 11 is 0.003% / hour or less. In the environmental adjustment process, it is more preferable that the standing time is set to a time when the rate of dimensional change per unit time of the sheet film 11 is 0.002% / hour or less. In the environment adjustment step, it is more preferable that the standing time is set to a time when the dimensional change rate per unit time of all of the long and short sides of the sheet film 11 is not more than the above value.
In the environment adjustment step, the leaving time is more preferably 6 hours or more.
In addition, said dimensional change rate is calculated | required from the dimensional change amount per unit time of the sheet | seat film 11. FIG. The dimensional change rate per unit time (% / hour) is calculated by the following formula (I).
W = (X / Y) × 100 (%) ÷ Z (hours) (I)
Here, in the above formula (I), “W” is the dimensional change rate (% / hour), and “X” is the time when the length of the long side or the short side of the film is measured twice over Z time. Dimensional change amount (mm), which is the difference between the first length and the second length, “Y” is the length of the long side or short side (mm) before the dimensional change. The time between them is “Z” (hours). The measurement of the length of the film twice with a Z time can be measured, for example, the first time before leaving the film and the second time after leaving the film.

(End face processing process)
As shown in FIG. 4, in the end face processing step, the end face processing film 11 A is obtained by polishing the end face 11 e (see FIGS. 6 and 7) along the four sides of the single wafer film 11 using a polishing apparatus (not shown). . For example, as a polishing apparatus, a medium and small size polishing machine (model PLBP300) manufactured by Megaro Technica Co., Ltd. can be used. The polishing amount is, for example, about 0.3 to 2 mm on each side.

As described above, the film manufacturing method according to the present embodiment is performed after the sheet-fed film acquisition step of acquiring the sheet-fed sheet film 11 from the long strip-shaped optical film F10X and the sheet-fed film acquisition step. An end face processing step of polishing an end face 11e of the leaf film 11 to obtain an end face processing film 11A, wherein the single wafer film 11 is left between the single wafer film acquisition step and the end face processing step. It further includes an environment adjustment step in which the leaving environment is set to an atmosphere at least adjusted in humidity.

According to the present embodiment, between the sheet film acquisition process and the end face processing process, by further including an environment adjustment process in which the leaving environment in which the sheet film 11 is left is in an atmosphere with at least humidity adjusted, There are effects like this. That is, compared with the case where the end face processing step is reached without going through the environment adjustment step, the end face processing film 11A can be obtained because the sheet film 11 can be stretched in advance in the environment adjustment step before the end face processing step. It is possible to prevent the end-face processed film 11A from being excessively stretched by wetting during use. Thus, the end face processed film 11A is cut out to a size that matches the display area P4 of the liquid crystal display panel P, and the size of the end face processed film 11A changes excessively when the end face processed film 11A is subsequently attached to the liquid crystal display panel P. Can be suppressed. Therefore, the dimensional accuracy of the film (end face processed film 11A) can be improved.

Also, in the environment adjustment process, the humidity and temperature of the leaving environment are brought close to the humidity and temperature at which the end face processed film 11A is used after the end face processing step, thereby providing the following effects. That is, in the environment adjustment process, the sheet film 11 can be stretched in advance in accordance with the usage environment of the end face processed film 11A. Therefore, when the end face processed film 11A is used, the end face processed film 11A is excessively wet. Can be effectively suppressed. Therefore, the dimensional accuracy of the film can be further improved.

Also, in the environmental adjustment process, as described above, the following effects are achieved by setting the standing time to be equal to or longer than the time when the dimensional change per unit time of the sheet film 11 approaches convergence. That is, in the environmental adjustment step, the sheet film 11 can be sufficiently stretched by wetness in advance, so that when the end face processed film 11A is used, the end face processed film 11A is effectively stretched by wetness. Can be suppressed. Therefore, the dimensional accuracy of the film can be further improved.

Also, in the environmental adjustment process, the following effects are achieved by setting the standing time to a time when the dimensional change rate per unit time of the sheet film 11 is 0.003% / hour or more. That is, in the environment adjustment step, the sheet film 11 can be stretched in advance to such an extent that the dimensional change does not occur any more. Therefore, when the end face processed film 11A is used, the end face processed film 11A is excessively stretched due to moisture. It can be effectively suppressed. Therefore, the dimensional accuracy of the film can be further improved.

Also, in the environmental adjustment process, the following effects can be obtained by setting the standing time to 6 hours or more. That is, in the environment adjustment step, the sheet film 11 can be sufficiently stretched by wet in advance in a time that can contribute to the dimensional change of the sheet film 11 to the maximum, so that when the end face processed film 11A is used, It is possible to effectively suppress the end face processed film 11 A from being excessively stretched by wetting by time management. Therefore, the dimensional accuracy of the film can be further improved, and workability by time management can be improved.

Also, in the environment adjustment process, the following effects are achieved by causing the main surface 11a of the sheet film 11 to be along the vertical direction V1. That is, as compared with the case where the main surface 11a of the sheet film 11 is set along the horizontal direction (for example, when the sheet film 11 is placed on a flat mounting table as it is), the sheet film 11 is not subjected to its own weight. The single wafer film 11 can be exposed as much as possible. Thereby, in the environmental adjustment process, since the single wafer film 11 can be sufficiently stretched by wetting in advance, when the end face processing film 11A is used, it is effectively prevented that the end face processing film 11A is excessively stretched by wetting. Can be suppressed. Therefore, the dimensional accuracy of the film can be further improved.

Moreover, in the environment adjustment process, the following effects are produced by exposing the end face 11e along the long side of the sheet film 11. That is, in the environment adjustment step, the sheet film 11 can be exposed as much as possible with the long end surface 11e as compared with the case where the end surface 11e along the short side of the sheet film 11 is exposed. Thereby, in the environmental adjustment process, since the single wafer film 11 can be sufficiently stretched by wetting in advance, when the end face processing film 11A is used, it is effectively prevented that the end face processing film 11A is excessively stretched by wetting. Can be suppressed. Therefore, the dimensional accuracy of the film can be further improved.

Moreover, in the environment adjustment process, the following effects can be obtained by forming a laminated body 12 in which a plurality of sheet films 11 are stacked. That is, in the environmental adjustment process, the sheet film 11 can be left in units of the laminated body 12, so that the workability is improved and the work time is reduced as compared with the case where the sheet film 11 is left alone. It can be shortened.

Moreover, in the environment adjustment process, the following effects are achieved by providing the dummy film 13 on the main surface side of the laminate 12. That is, in the environmental adjustment process, a plurality of sheet films 11 inside the dummy film 13 can be protected in the thickness direction of the laminated body 12, and therefore, disturbance or the like affects when the sheet film 11 is stretched by wetting. Can be kept as small as possible. Therefore, the dimensional accuracy of the film can be further improved.

Also, in the end face processing step, the end face 11e of the sheet film 11 is polished, and the following effects are obtained. That is, in the end face processing step, since the end face 11e of the single wafer film 11 can be processed more smoothly than in the case of cutting the end face 11e of the single wafer film 11, the size of the end face processed film 11A is the product. It becomes easy to adapt to size.

Hereinafter, modifications of the embodiment of the film manufacturing method according to the present invention will be described. In the following modifications, the same reference numerals are given to components common to the above embodiment, and detailed description thereof is omitted.

(Modification of the state of leaving a sheet film)
FIG. 8 is a perspective view showing a modified example of the leaving state of the sheet film 11 in the environment adjustment process.
In the said embodiment, the example (refer FIG. 7) by which the laminated body 12 was supported by the film support stand 30 provided with the base 31 and the support pillar 32 was given. On the other hand, in this modification, as shown in FIG. 8, the laminated body 12 is mounted on the film mounting table 40 having an L-shaped cross section.

As shown in FIG. 8, the film mounting table 40 is connected to one end of the rectangular plate-shaped first support plate 41 and the first support plate 41, and stands up in the direction along the vertical direction V 1. And a second support plate 42 having a rectangular plate shape having a longitudinal direction in the thickness direction.

In the film mounting table 40, the length of the first support plate 41 and the second support plate 42 along the thickness direction of the laminate 12 is sufficiently longer than the thickness of the laminate 12. The laminated body 12 is supported so as to lean against the second support plate 42 so that one short side thereof is along the second support plate 42. The thickness of the second support plate 42 is sufficiently large so that the posture of the stacked body 12 can be maintained. In the film mounting table 40, an end surface along the long side of the laminate 12 opposite to the first support plate 41 of the sheet film 11 and the short side of the sheet film 11 opposite to the second support plate 42. 11e is exposed. Thereby, since the sheet | seat film 11 can be exposed as much as possible, the sheet | seat film 11 can fully be wetted in an environmental adjustment process.

FIG. 9 is a perspective view showing another modified example of the leaving state of the sheet film 11 in the environment adjustment process.
In the above modification, an example (see FIG. 8) in which the laminate 12 is supported by leaning against the second support plate 42 so that one short side thereof is along the second support plate 42 has been described. On the other hand, in this modified example, as shown in FIG. 9, the laminated body 12 has the second support so that a part of one long side (lower part of the laminated body 12) is along the second support plate 42. It leans against the plate 42 and is supported. In other words, the stacked body 12 stands up so that the longitudinal direction thereof follows the vertical method V1.

According to the present modification, the laminated body 12 is supported by leaning against the second support plate 42 so that a part of one long side thereof is along the second support plate 42, as described below. There is an effect. That is, as compared with the case where the laminate 12 is supported by leaning against the second support plate 42 so that one short side thereof is along the second support plate 42, the sheet film 11 is formed with the long end surface 11e. It can be exposed as much as possible. Thereby, in the environmental adjustment process, since the single wafer film 11 can be sufficiently stretched by wet in advance, when the end face processed film 11A is used, it is effectively prevented that the end face processed film 11A is excessively stretched by wet. Can be suppressed. Therefore, the dimensional accuracy of the film can be further improved.

Note that the present invention is not necessarily limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

For example, when the shape of the sheet film 11 is other than a rectangular shape (for example, rhombus, hexagon, octagon, circle, or ellipse), the end face of the sheet film 11 is made possible in the environmental adjustment process. It is preferable to expose it. Specifically, it is preferable to expose the longest edge among the edges of the sheet film 11. Thereby, the sheet | seat film 11 can fully be extended by moistening in an environmental adjustment process.

In the present invention, when the sheet film 11 has a symmetrical shape (for example, a square, a rhombus, a regular hexagon, a regular octagon, or a circle), the following effects can be obtained. That is, since the dimensional change of the sheet film 11 can be uniformly suppressed from the end surface to the center portion, the stress due to the dimensional change can be relaxed. Therefore, the curl change of the sheet | seat film 11 and generation | occurrence | production of the crack of an edge part can be suppressed.

The end face processed film 11A obtained by the film manufacturing method of the present embodiment is subjected to end face processing after sufficiently changing the dimensions of the single-wafer film 11 in an environmental adjustment step. Therefore, even if the end face processed film 11A is left in the same environment (for example, the same humidity and the same temperature) as the environment adjustment step, the dimensional change hardly occurs. Such an effect is particularly remarkable when an optical film (particularly a polarizing film) is used as the resin film.

Also, when the optical film is bonded to the display device, it is important to keep the longest edge side dimension change small. For example, when kept for 24 hours in an environment of humidity 47% to 57% and temperature 18 ° C. to 28 ° C., the dimensional change rate of the longest edge is preferably less than 0.0002% / hour, Preferably it is 0.0001% / hour or less. Usually, the dimensional change rate of the resin film is 0.00001% / hour or more.

When the optical film has a rectangular shape, the dimensional change rate of the two long sides is less than 0.0002% / hour when held for 24 hours in an environment of humidity 52% and temperature 23 ° C. Preferably there is. Thereby, a film with improved dimensional accuracy can be provided.

In the above-described embodiment, the example in which the sheet film 11 is moistened in the environment adjustment process has been described. However, the present invention is not limited to this. For example, the sheet film 11 may be dried in the environment adjustment step.

In the above embodiment, the example in which the end face of the sheet film is polished in the end face processing step has been described. However, the present invention is not limited to this. For example, in the end face polishing step, the end face of the single wafer film may be processed by cutting such as laser cutting. Thereby, even when it is a case where it is set as the laminated body which laminated | stacked the sheet | seat film in multiple, in the end surface grinding | polishing process, since the end surface of a laminated body can be cut | disconnected collectively with a laser cut, workability | operativity can be improved. .

In the above embodiment, the example in which an optical film is used as the resin film has been described. However, the present invention is not limited to this. The effect of the present invention can be sufficiently obtained as long as the film to be used is capable of causing dimensional changes such as expansion and contraction due to humidity.

As described above, the preferred embodiments according to the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to such examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

Hereinafter, the present invention will be described more specifically by way of examples. However, the present invention is not limited to the following examples.

Example 1
The present inventor confirmed that the film can be stretched longer by exposing the long side rather than the short side of the film by adjusting the leaving environment using a rectangular film.

As a film to be evaluated, a rectangular optical film (a sheet film 11 cut out from a long belt-shaped optical film F10X as shown in FIG. 4) was used. The length of the long side of the film was 110 mm. The short side length of the film was 60 mm. The thickness of the film was 200 μm.

FIG. 10 is a diagram for explaining the dimensional change amount of the long side of the film in the example. FIG. 11 is a diagram for explaining the dimensional change amount of the short side of the film in the example. In each graph of FIG.10 and FIG.11, a horizontal axis shows time [hour] and a vertical axis | shaft shows dimensional change [micrometer].

The temperature of the leaving environment in this example was 23 ° C.
The humidity of the leaving environment was set to three conditions of 45%, 55%, and 65%. In the graphs of FIG. 10 and FIG. 11, ◇ indicates humidity 45%, □ indicates humidity 55%, and Δ indicates humidity 65%.
The moisture content (initial moisture content) of the film was set to three conditions of 0.284%, 0.476%, and 0.594%. 10 and 11, the solid line is a graph with a moisture content of 0.284%, the alternate long and short dash line is the graph with a moisture content of 0.476%, and the broken line is a graph with a moisture content of 0.594%. The moisture content of the film was measured by a dry weight method. The sample used for the measurement by the dry weight method was a square having a side length of 100 mm. The drying conditions at this time were a temperature of 105 ° C. and a drying time of 2 hours. Here, when the moisture content is “α”, the sample weight before drying is “M1”, and the sample weight after drying is “M2”, the relationship of the following equation (1) is established.
α = (M1−M2) / M1 (1)

As shown in the graphs of FIGS. 10 and 11, the dimensional change amount of the long side is larger than the dimensional change amount of the short side under any of the moisture ratio and humidity conditions. In addition, the dimensional change amount on the long side was about twice as large as the dimensional change amount on the short side in each moisture ratio and each humidity condition.
From the above, it was confirmed that the film can be stretched longer by exposing the long side rather than the short side of the film by adjusting the leaving environment using a rectangular film.

(Example 2)
By adjusting the leaving environment using a rectangular film, the present inventor made it possible to “extend the film longer than when the film is not exposed” and “the dimensions of each side”. The change was confirmed by the following evaluation about “coming closer to convergence after 6 hours”.

As the film to be evaluated, a rectangular optical film (a single-wafer film 11 cut out from an elongated optical film F10X as shown in FIG. 4) was used. The length of the long side of the film was 110 mm. The short side length of the film was 60 mm. The thickness of the film was 200 μm.
The film is left standing one by one (state leaning on a film leaning base 20 as shown in FIG. 6), or in a laminated state (state supported on a film support 30 as shown in FIG. 7). ). In the state which used the film as the laminated body, the film which exists in two positions of a center part and an edge part in the thickness direction of this laminated body was used among the laminated bodies. In addition, the center part in the thickness direction of the laminated body corresponds to a portion T1 shown in FIG. 7 (for example, the 50th sheet when 100 films are stacked to form a laminated body). The end portion in the thickness direction of the laminated body corresponds to a portion T2 shown in FIG. 7 (for example, the 25th sheet when 100 films are stacked to form a laminated body).

FIG. 12 is a diagram for explaining the state of leaving the film in this example. In FIG. 12, the symbol J1 is the first long side covered with the first wall W1, the symbol J2 is the second long side exposed to the outside on the opposite side of the first long side W1, and the symbol K1 is the second long side. The first short side covered with the wall W2 and the symbol K2 indicate the second short side exposed to the outside on the opposite side of the first short side K1.

FIG. 13 is a diagram for explaining the dimensional change amount of the first long side of the film in this example. FIG. 14 is a diagram for explaining the dimensional change amount of the second long side of the film in this example. FIG. 15 is a diagram for explaining the dimensional change amount of the first short side of the film in this example. FIG. 16 is a diagram for explaining the dimensional change amount of the second short side of the film in this example. In each graph of FIGS. 13 to 16, the horizontal axis represents time [hour], and the vertical axis represents the dimensional change [μm].

In this example, the temperature of the standing environment was 23 ° C. and the humidity was 55%.
As described above, the film was left standing one by one, or a laminated body. In the state which used the film as the laminated body, the film which exists in two positions of a center part and an edge part in the thickness direction of this laminated body was used among the laminated bodies.
In each graph of FIG. 13 to FIG. 16, ◇ indicates a state of standing one by one, □ indicates a center portion in the thickness direction of the laminate, and Δ indicates an end portion in the thickness direction of the laminate.
The moisture content (initial moisture content) of the film was set to two conditions of 0.289% and 0.361%.
In each graph of FIGS. 13 to 16, the solid line indicates a graph with a moisture content of 0.289%, and the alternate long and short dash line indicates a graph with a moisture content of 0.361%. The moisture content was calculated using the above formula (1).

As shown in FIG. 13 and FIG. 14, the result is that the dimensional change amount of the second long side tends to be larger than the dimensional change amount of the first long side in each leaving state and each moisture content. Got.
As shown in FIGS. 15 and 16, the dimensional change amount of the second short side is not as different as the result of the dimensional change amount of the long side, but the first short side is not changed in each standing state and each moisture content. The result that it tends to become larger than the dimensional change amount of the side was obtained.
Further, as shown in the graphs of FIGS. 13 to 16, it was obtained that the dimensional change amount of each side became the largest by the time 6 hours passed.
As described above, it was confirmed that by adjusting the leaving environment using a rectangular film, the film can be stretched longer when the film is exposed than when the film is not exposed. In addition, it was confirmed that the dimensional change of each side of the film approaches the convergence after 6 hours have passed.

(Example 3)
The present inventor has confirmed by the following evaluation that the dimensional accuracy of the film can be improved by adjusting the leaving environment using a rectangular film.

As the film to be evaluated, a rectangular optical film (a single-wafer film 11 cut out from an elongated optical film F10X as shown in FIG. 4) was used. The length of the long side of the film was 110 mm. The short side length of the film was 60 mm. The thickness of the film was 200 μm.
As described above, the film was left standing one by one, or a laminated body. In the state which used the film as the laminated body, the film which exists in two positions of a center part and an edge part in the thickness direction of this laminated body was used among the laminated bodies.

In addition, the film manufacturing method of the comparative example shall have no environmental adjustment process. In the comparative example, the end face processing step is reached without going through the environment adjustment step.

On the other hand, the film manufacturing method of this example has an environmental adjustment step. In a present Example, it has an environmental adjustment process between a sheet-fed film acquisition process and an end surface processing process. In this example, the temperature of the leaving environment was 23 ° C., the humidity was 52%, and the leaving time was 48 hours.

Further, in the end face processing steps of the present example and the comparative example, the above-described medium and small size polishing machine (model PLBP300) manufactured by Megaro Technica Co., Ltd. was used as a polishing apparatus. The polishing conditions were a parallel arbor, a rotational speed of 4000 rpm, a feed rate of 500 mm / min, a clamp pressure of 0.06 MPa, and a cutting amount (0.5 mm on one side).

FIG. 17 is a diagram showing a dimensional change amount of the first long side of the film in this example and the comparative example. FIG. 18 is a diagram showing the dimensional change amount of the second long side of the film in this example and the comparative example. FIG. 19 is a diagram showing the dimensional change amount of the first short side of the film in this example and the comparative example. FIG. 20 is a diagram showing the dimensional change amount of the second short side of the film in this example and the comparative example. In each graph of FIGS. 17 to 20, the horizontal axis represents time [day], and the vertical axis represents the dimensional change [μm]. In each graph of FIGS. 17 to 20, the solid line indicates the graph of the example, and the broken line indicates the graph of the comparative example.

FIGS. 17 to 20 are graphs when the film is left again in the leaving environment after the end face processing step. That is, FIG. 17 to FIG. 20 show the results of confirming the dimensional change of the film obtained through the end face processing step in a standing environment (temperature 23 ° C., humidity 52%).

As described above, the film was left standing one by one and a laminated body. In the state made into the laminated body, the film which exists in two positions of a center part and an edge part in the thickness direction of this laminated body was used among the laminated bodies.
In each graph of FIG. 17 to FIG. 20, ◇ indicates a state of standing one by one, □ indicates a center portion in the thickness direction of the laminate, and Δ indicates an end portion in the thickness direction of the laminate.

As shown in the graphs of FIGS. 17 to 20, the result was that the dimensional change amount of this example was smaller than the dimensional change amount of the comparative example in each side and in each leaving state.
In particular, on the long side where the dimensional change is likely to occur, the result was that the dimensional change amount of the example was significantly smaller than the dimensional change amount of the comparative example.
Here, in the comparative example, as shown in FIG. 17, the dimensional change amount becomes maximum at the first long side of the film located at the end portion (Δ mark shown in FIG. 17) in the thickness direction of the laminated body, and the time is 7 days. And obtained a result of about 30 μm.
On the other hand, in this example, the dimensional change amount is maximum at the first long side of the film at the position of the central portion (□ mark shown in FIG. 17) in the thickness direction of the laminated body, and is about 10 μm at 7 days. Results were obtained.

Table 1 below shows the dimensional change rate of the long side in the present example and the comparative example, which was obtained from the result of the dimensional change amount in the present example and the comparative example.
In addition, the dimensional change rate (% / hour) of the long side was calculated by the following formula (2).
D = (E / H) × 100 (%) ÷ 24 (hours) (2)
Here, in the above formula (2), “D” is the dimensional change rate (% / hour) of the long side, “E” is the dimensional change amount (mm) of the long side when the film is held for 24 hours, “ “H” is the length (mm) of the long side before the dimension change. In this embodiment, H = 110 mm. In Table 1 below, the dimensional change rate of the long side after 4 days or 7 days was obtained by holding “E” for 4 days (96 hours) or 7 days (168 hours) in the above formula (2). It is a value calculated with the dimensional change amount (mm) of the long side at the time and 24 (hours) as 96 (hours) or 168 (hours).

As shown in Table 1, in the comparative example, when the film is left standing one by one, the dimensional change rate is maximized on the first long side, and the result is 0.0005% / hour. It was.
On the other hand, in the examples, the film is left standing one by one, and is a laminated body (when a film is used at two positions in the center and the end in the thickness direction of the laminated body). In all cases, the dimensional change rate of the long side of the film was 0.0001% / hour or less.
From the above, it was confirmed that the dimensional accuracy of the film can be improved by adjusting the leaving environment using a rectangular film.

11 ... Sheet-fed film 11A ... End-face processed film 11a ... Main surface of sheet-fed film 11e ... End surface of sheet-fed film 12 ... Laminate 13 ... Dummy film F10X ... Optical film (resin film)

Claims

A sheet-fed film acquisition step of acquiring a sheet-fed film that is a sheet-fed resin film from a long strip-shaped resin film;
An end face processing step of processing an end face of the single wafer film to obtain an end face processed film after the single wafer film acquisition process,
The film manufacturing method which further includes the environmental adjustment process which makes the leaving environment which leaves the said single wafer film leave in the atmosphere which adjusted the humidity at least between the said single wafer film acquisition process and the said end surface processing process.
In the environmental adjustment step, the humidity and temperature of the leaving environment are in a range of ± 5% and ± 5 ° C with respect to the humidity and temperature at which the end face processed film is used after the end face processing step. The film manufacturing method of description.
3. The film production according to claim 1, wherein, in the environmental adjustment step, a time during which the sheet film is left in the leaving environment is equal to or longer than a time when a dimensional change per unit time of the sheet film approaches convergence. Method.
4. In the environmental adjustment step, the time for which the single-wafer film is left in the leaving environment is set to a time when the dimensional change rate per unit time of the single-wafer film is 0.003% / hour or less. The film manufacturing method of description.
The film manufacturing method according to claim 3 or 4, wherein in the environmental adjustment step, the time for which the single-wafer film is left in the leaving environment is 6 hours or more.
The film manufacturing method according to any one of claims 1 to 5, wherein in the environmental adjustment step, the single-wafer film is left with the main surface of the single-wafer film along a vertical direction.
The sheet film is rectangular,
The film manufacturing method according to any one of claims 1 to 6, wherein, in the environmental adjustment step, an end surface along a long side of the single-wafer film is exposed and the single-wafer film is left as it is.
The film manufacturing method according to any one of claims 1 to 7, wherein in the environment adjustment step, the laminate is left as a laminate in which a plurality of the single-wafer films are stacked.
The film manufacturing method according to claim 8, wherein, in the environmental adjustment step, a dummy film is provided on a main surface side of the laminated body and the laminated body is left as it is.
The film manufacturing method according to any one of claims 1 to 9, wherein, in the end face processing step, the end face of the single wafer film is polished.
The film manufacturing method according to any one of claims 1 to 10, wherein the resin film is an optical film.
Has a rectangular shape,
A film having a dimensional change rate of two long sides of less than 0.0002% / hour when held for 24 hours in an environment of humidity 52% and temperature 23 ° C.