JP2021140115A - Optical laminate film manufacturing device and optical laminate film manufacturing method - Google Patents

Abstract

To provide an optical laminate film manufacturing device with which it is possible to easily manufacture an optical film in a state with desired curls added or in a flat state.SOLUTION: Provided is a manufacturing device 5 for an optical laminate film 1 comprising an optical film 2 having an adhesive layer 3 and a separator film 4 pasted together via the adhesive layer 3. This manufacturing device includes: conveyance devices 62, 64 for conveying the optical film 2 and the separator film 4 to a laminate roller 7; a laminate roller 7 including a first roller 71 and a second roller 72 for pasting the optical film 2 and the separator film 4 together; and a curl adjustment roller 8 for adjusting curls of the optical laminate film 1 and arranged on the exit side of the laminate roller 7. The curl adjustment roller 8 is, while in contact with a first face of the optical laminate film 1, capable of displacing the conveyance path for the optical laminate film 1 on the exit side of the laminate roller 7 to the first roller 71 side and second roller 72 side, respectively.SELECTED DRAWING: Figure 3

Description

The present invention relates to an optical laminated film manufacturing apparatus having an optical film and a separator film, and more particularly to an optical laminated film manufacturing apparatus capable of adjusting the curl of the optical film and a manufacturing method thereof.

Conventionally, an optical film has been used in an image display device such as a liquid crystal display device or an organic EL display device. Examples of the optical film include a polarizing film containing a polarizer, a retardation film, and a light diffusing film. Further, the polarizing film and the like are also used for applications other than image display devices such as polarized sunglasses and dimming windows.
An adhesive layer may be laminated on the optical film in order to attach it to the screen of an image display device or the like. An optical film having a pressure-sensitive adhesive layer is provided, for example, in the form of an optical laminated film in which a separator film is laminated on the pressure-sensitive adhesive layer.
Such an optical laminated film is obtained by laminating an optical film and a separator film via an adhesive layer. However, since the optical film is generally subjected to various treatments such as stretching treatment, it tends to be in a curled state.

In order to correct the curl of such an optical film, Patent Document 1 discloses a laminated film laminating device including a curl correcting portion for correcting the curl generated in the laminated film sent out from the laminating portion. There is. The bonding device of Patent Document 1 conveys the sheet-fed base film A and the continuous base film B to the bonding section 20, respectively, and laminates both films by bonding rollers 21U and 21L of the bonding section 20. Form film C. A curl correction roller 31 is arranged on the exit side of the bonding rollers 21U and 21L. By raising the curl correction roller 31, the roller 21U follows the transport path of the laminated film C coming out of the bonding rollers 21U and 21L. Displace to the side. By setting the transport path of the laminated film C on the exit side of the laminated portion 20 upward (the carry-out angle of the laminated film C protruding from the laminated portion 20 is upward) in this way, the downward curl of the laminated film C can be corrected. .. As the reference numeral, the reference numeral described in Patent Document 1 is used as it is.

Japanese Patent No. 4415126

However, with the bonding device of Patent Document 1, even if the curl in one direction (downward curl) can be corrected, the curl in the opposite direction cannot be corrected appropriately.
Specifically, when the curl correction roller 31 is lowered, the transport path of the laminated film C coming out of the bonding portion 20 becomes horizontal, but the transport path of the laminated film C does not change any more. That is, even if the curl correction roller 31 is sufficiently lowered, the transport path of the laminated film C on the exit side of the bonding portion 20 cannot be directed downward (the carry-out angle of the laminated film C protruding from the bonding portion 20 is downward). .. Therefore, the bonding device of Patent Document 1 can correct only one-way curl.
Depending on the application, a curled optical film having a convex first surface side, a curled optical film having a convex second surface side, and a flat optical film are required. With conventional equipment, it is difficult to easily produce the desired curl or flat optical film.

An object of the present invention is to provide an optical laminated film manufacturing apparatus and a method for manufacturing an optical laminated film, which can easily manufacture an optical film in a desired curled state or a flat state.

In the present invention, in an optical laminated film manufacturing apparatus having an optical film having an adhesive layer and a separator film bonded to the optical film via the adhesive layer, the optical film and the separator film are laminated, respectively. A transport device for transporting to a roller, a laminate roller having a first roller and a second roller for forming the optical laminated film by laminating the optical film and a separator film via the pressure-sensitive adhesive layer, and the laminate. It has a curl adjusting roller which is arranged on the outlet side of the roller and adjusts the curl of the optical laminated film, and the curl adjusting roller is in contact with the first surface of the optical laminated film while being in contact with the first surface of the optical laminated film. The transport path of the optical laminated film in the above can be displaced to the first roller side and the second roller side, respectively.

In a preferred manufacturing apparatus of the present invention, the laminating roller sandwiches the optical film and the separator film without tension cutting, and the two films are bonded together.
In a preferred manufacturing apparatus of the present invention, the conveying apparatus has a feed adjusting unit for adjusting a feed amount of either one of the optical film and the separator film to the laminate roller.
The preferred manufacturing apparatus of the present invention further has a guide roller on the downstream side of the curl adjustment roller, and the optical laminated film ejected from the laminate roller is bent by the curl adjustment roller in a side view and the guide. It is transported in contact with the rollers.
In the preferred manufacturing apparatus of the present invention, the second surface of the optical laminated film in contact with the curl adjusting roller is free on the second surface opposite to the first surface.
In the preferred manufacturing apparatus of the present invention, the optical film contains a polarizer.
In a preferred manufacturing apparatus of the present invention, the curl adjusting roller causes the optical film of the optical laminated film to be curled with the first surface side convex, curl with the second surface side convex, or flat. Adjust to the state of.

According to another aspect of the present invention, there is provided a method for producing an optical laminated film.
The method for producing an optical laminated film of the present invention is a step of transporting the optical film and the separator film to a laminating roller having a first roller and a second roller, respectively, and the optical film and the separator film are transferred to the first roller and the second roller. A step of obtaining an optical laminated film by passing the optical film and a separator film together via an adhesive layer, and curling the optical laminated film by a curl adjusting roller arranged on the outlet side of the laminate roller. The curl adjusting roller is in contact with the first surface of the optical laminated film, and the transport path of the optical laminated film on the outlet side of the laminated roller is set to the first roller side and the second roller. Displace each on the roller side.

In a preferred manufacturing method of the present invention, the laminating roller sandwiches the optical film and the separator film without tension cutting, and the two films are bonded together.
A preferred manufacturing method of the present invention further comprises a guide roller on the downstream side of the curl adjustment roller, and the optical laminated film coming out of the laminate roller is bent by the curl adjustment roller in a side view. Transport in contact with the guide roller.

According to the manufacturing apparatus and manufacturing method of the present invention, it is possible to easily manufacture an optical film in a state with a desired curl or in a flat state.

The schematic side view which shows the layer structure of the optical laminated film of one Embodiment. The schematic side view which shows the layer structure of the optical laminated film of another embodiment. The schematic side view which shows the manufacturing apparatus of an optical laminated film. The schematic side view which shows the state which moved the curl adjustment roller of the manufacturing apparatus to the 1st roller side. An enlarged side view of the vicinity of the laminating roller and the curl adjusting roller in the state of FIG. The schematic side view which shows the state which moved the curl adjustment roller of the manufacturing apparatus to the 2nd roller side. An enlarged side view of the vicinity of the laminating roller and the curl adjusting roller in the state of FIG. (A) is a reference side view showing an optical laminated film with a curl on the first surface side, and (b) is an optical laminated film with a curl on the second surface side. A reference side view showing the above, (c) is a reference side view showing an optical laminated film in a flat state. The reference side view which shows the method of confirming the curl or flatness of an optical laminated film (optical film).

In the present specification, the downstream side means the leading side of the transport of the film, and the upstream side means the opposite side of the transport. In the present specification, "first" and "second" may be added to the beginning of terms, but the first and the like are added only for distinguishing the terms, and their order and superiority or inferiority. It has no special meaning such as. Further, the numerical range represented by "lower limit value X to upper limit value Y" means a lower limit value X or more and an upper limit value Y or less. When a plurality of the numerical values are described separately, it is possible to select an arbitrary lower limit value and an arbitrary upper limit value and set "arbitrary lower limit value to arbitrary upper limit value".

[Optical laminated film]
1 and 2 illustrate the layer structure of the optical laminated film 1 of the present invention.
The optical laminated film 1 of the present invention has an optical film 2, a separator film 4, and an adhesive layer 3 that is interposed between the optical film 2 and the separator film 4 to bond both films 2 and 4. The pressure-sensitive adhesive layer 3 is firmly adhered to the optical film 2 and is detachably adhered to the separator film 4.
Therefore, the separator film 4 can be peeled off at the interface with the pressure-sensitive adhesive layer 3. By peeling off the separator film 4, the optical laminated film 1 can be separated into an optical film 2 having an adhesive layer 3 and a separator film 4.

The optical film 2 includes an optical functional film. Examples of the optical functional film include a polarizer, a retardation film, a light diffusing film, a brightness improving film, an antiglare film, and a light reflecting film. The polarizer is a film having a property of transmitting light (polarized light) vibrating in one specific direction and blocking light vibrating in the other direction. The retardation film is a film exhibiting optical anisotropy, and typical examples thereof include 1 / 2λ film and 1 / 4λ film.
Further, the optical film 2 may include a protective film. The protective film is laminated for the purpose of protecting the optical functional film. As the protective film, a colorless and transparent film having no optical anisotropy is typically used.

In the optical laminated film 1 illustrated in FIG. 1, the optical film 2 has a first protective film 21, a polarizer 22, a second protective film 23, and a surface protective film 24 in this order from the bottom of the drawing. One laminated film (optical film 2) is formed by adhering the films 21, 22, 23, 24 to each other. In the illustrated example, the first protective film 21 and the polarizer 22, the polarizer 22 and the second protective film 23, and the second protective film 23 and the surface protective film 24 are directly adhered to each other. If necessary, an adhesive layer (or an adhesive layer) may be interposed between these films, and each film may be adhered via an adhesive layer (or an adhesive layer) (not shown). ..

In the optical laminated film 1 illustrated in FIG. 2, the optical film 2 has a retardation film 25 and a surface protective film 26 in this order from the bottom of the drawing. One laminated film (optical film 2) is formed by adhering the films 25 and 26 to each other. In the illustrated example, the retardation film 25 and the surface protective film 26 are directly adhered to each other, but if necessary, an adhesive layer (or an adhesive layer) is interposed between the films. Each film may be adhered via an adhesive layer (or an adhesive layer) (not shown).
The optical film 2 is not limited to the layer structure shown in FIGS. 1 and 2, and can be changed in various ways. For example, the optical film 2 may include two or more layers of optical functional films, or may be composed of only one layer of optical functional films.

The pressure-sensitive adhesive layer 3 provided on the second surface of the optical film 2 has adhesiveness at room temperature, and the adhesiveness is maintained even after peeling and can be reattached. The pressure-sensitive adhesive layer 3 is composed of a known pressure-sensitive adhesive. Examples of the adhesive include a colorless and transparent acrylic adhesive, a rubber adhesive, a silicone adhesive, a urethane adhesive, a vinyl alkyl ether adhesive, a polyvinylpyrrolidone adhesive, a polyacrylamide adhesive, and a cellulose adhesive. Adhesives and the like can be mentioned.
The thickness of the pressure-sensitive adhesive layer 3 is not particularly limited, but is, for example, 0.1 μm to 50 μm, preferably 1 μm to 30 μm. When the thickness of the pressure-sensitive adhesive layer 3 is within the above range, the pressure-sensitive adhesive layer 3 having appropriate peelability and reattachability can be formed.

The separator film 4 is not particularly limited, but a film that does not contain an optical functional film is usually used.
The separator film 4 has a release surface having excellent peelability with respect to the pressure-sensitive adhesive layer.
Examples of the separator film 4 include resin films such as polyethylene, polypropylene, polyethylene terephthalate, and polyester film; paper; porous films such as woven cloth, non-woven fabric, and net cloth; foamed resin film; and the like. The separator film 4 is preferably a resin film because it has excellent surface smoothness.
Examples of the resin film include polyethylene terephthalate film, polybutylene terephthalate film, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyurethane film, and ethylene. -Vinyl acetate copolymer film and the like can be mentioned.
In general, the surface (release surface) of the separator film 4 is generally peeled off. Although it depends on the material of the separator film 4 and the material of the pressure-sensitive adhesive layer 3, if the separator film 4 itself is made of a material having excellent peelability to the pressure-sensitive adhesive layer 3, the peeling treatment may not be performed. be. Examples of the peeling treatment include applying a silicone-based, fluorine-based, long-chain alkyl-based, or fatty acid amide-based release agent.
The thickness of the separator film 4 is not particularly limited, and is, for example, 5 μm to 200 μm, preferably 10 μm to 100 μm.

[Optical laminated film manufacturing equipment]
FIG. 3 is a schematic side view of the manufacturing apparatus for the optical laminated film 1.
The manufacturing apparatus 5 of FIG. 3 can manufacture the long strip-shaped optical laminated film 1. The long strip shape refers to a substantially rectangular shape in a plan view in which the length in the longitudinal direction is sufficiently longer than that in the width direction. As the long strip, for example, the length in the width direction is 1000 mm to 4000 mm, the length in the longitudinal direction is 5 m or more, and the length in the longitudinal direction is preferably 10 m or more. The width direction is a direction orthogonal to the longitudinal direction.
With reference to FIG. 3, the manufacturing apparatus 5 includes a conveying device for conveying the optical film 2 and the separator film 4, a laminating roller 7 for laminating the optical film 2 and the separator film 4 via the adhesive layer 3. It has a curl adjusting roller 8 arranged on the outlet side of the laminate roller 7 and adjusting the curl of the optical film 2, and a guide roller 9 arranged on the downstream side of the curl adjusting roller 8. The white arrows in FIGS. 3 to 7 indicate the transport directions of the optical film 2, the separator film 4, and the optical laminated film 1.

Specifically, the transport device transports the optical film 2 on which the pressure-sensitive adhesive layer 3 is laminated on the second surface and the separator film 4 independently to the laminating roller 7. Both the optical film 2 and the separator film 4 have a long strip shape, and the transport device transports the films 2 and 4 in the longitudinal direction thereof.
The transport device includes a nip roller 61, a transport unit 62 for transporting the optical film 2 (hereinafter referred to as an optical film transport unit 62), and a transport unit 64 for transporting the separator film 4 (hereinafter referred to as a separator transport unit 64). Have.
The nip roller 61 is composed of a pair of rollers.
The optical film transport unit 62 has at least one guide roller 621 arranged between the nip roller 61 and the laminate roller 7. On the exit side of the nip roller 61, the optical film 2 is conveyed to the laminate roller 7 with the second surface in contact with the guide roller. At the exit side of the nip roller 61, the optical film 2 is conveyed to the laminate roller 7 by a transfer path independent of the separator film 4. Here, the first surface refers to one surface of the film, and the second surface refers to the side opposite to the first surface. The first surface of the optical film 2 is the surface on which the pressure-sensitive adhesive layer 3 is not provided, and the second surface of the optical film 2 is the surface opposite to the first surface, and the pressure-sensitive adhesive layer 3 is provided. It is a provided surface.
The optical film transport unit 62 may be provided with a known device such as a tension meter for measuring the tension of the optical film 2, if necessary.

The separator transport section 64 includes at least one guide roller 641 arranged between the nip roller 61 and the laminate roller 7, and a feed adjusting section for adjusting the feed amount of the separator film 4 to the laminate roller 7. The feed adjusting unit has a dancer roller 642, preferably a dancer roller 642 and a pendulum roller 643 arranged on the downstream side of the dancer roller 642. The dancer roller 642 can move in one direction (up and down in the drawing) while being in contact with the separator film 4. By moving the dancer roller 642, the feed amount of the separator film 4 to the laminate roller 7 can be adjusted. The pendulum roller 643 swings in an arc shape in a side view around a support shaft 646 fixed to a fixed side 645 (for example, a frame of equipment or a ceiling surface). FIG. 3 shows the moving direction of the dancer roller 642 and the swinging direction of the pendulum roller 643 with arrows.
On the exit side of the nip roller 61, the separator film 4 is conveyed to the laminate roller 7 while being in contact with the guide roller 641, the dancer roller 642, and the pendulum roller 643. On the exit side of the nip roller 61, the separator film 4 is conveyed to the laminate roller 7 by a transfer path independent of the optical film 2. The transport path of the separator film 4 here is longer than the transport path of the optical film 2 described above.
If necessary, the optical film transport unit 62 and the separator transport unit 64 may be provided with known equipment (not shown) such as a tension meter for measuring the tension of the optical film 2.

The laminate roller 7 is composed of a first roller 71 and a second roller 72 facing each other. By sandwiching the separator film 4 and the optical film 2 in the gap between the first roller 71 and the second roller 72, the separator film 4 is bonded to the adhesive layer 3 provided on the optical film 2. Therefore, the separator film 4 and the optical film 2 that have entered the laminating roller 7 pass through the laminating roller 7 to become the optical laminated film 1.
The sizes of the first roller 71 and the second roller 72 of the laminate roller 7 are not particularly limited, and may be, for example, the same diameter as the curl adjustment roller 8, or may be larger or smaller than that of the curl adjustment roller 8. Preferably, the diameters of the first roller 71 and the second roller 72 of the laminate roller 7 are larger than the diameter of the curl adjusting roller 8. For example, the diameters of the first roller 71 and the second roller 72 of the laminate roller 7 are 1.5 times or more, preferably 2 times or more the diameter of the curl adjusting roller 8.

The laminating roller 7 sandwiches the optical film 2 and the separator film 4 without tension cutting, and attaches both films 2 and 4 together. A normal laminate roller (nip roller) is a so-called tension cut roller, but the laminate roller 7 of the present application does not cut the tension of the optical film 2 and the separator film 4 at the time of bonding (does not absorb the tension). The laminate roller 7 of the present application gently presses both films 2 and 4 to such an extent that the optical film 2 and the separator film 4 can be bonded to each other via the adhesive layer 3, but does not excessively press both films 2 and 4. Is set to.

A curl adjusting roller 8 for adjusting the curl of the optical film 2 is arranged on the outlet side of the laminate roller 7. The curl adjusting roller 8 can be moved in a direction substantially vertical to the first surface of the optical laminated film 1 while being in contact with the first surface of the optical laminated film 1 protruding from the laminated roller 7. The second surface of the optical laminated film 1 in contact with the curl adjusting roller 8 opposite to the first surface is free. The free second surface means a state in which a member such as a roller does not contact the second surface and the second surface is merely in contact with air. The first surface of the optical laminated film 1 corresponds to the first surface of the optical film 2, and the second surface of the optical laminated film 1 corresponds to the surface opposite to the pressure-sensitive adhesive layer of the separator film.
In the example of FIG. 3, the curl adjusting roller 8 is movable in the left-right direction of the paper surface (both the left side and the right side of the paper surface). FIG. 3 shows the moving direction of the curl adjusting roller 8 with arrows. The curl adjusting roller 8 displaces the transport path of the optical laminated film 1 on the exit side of the laminated roller 7 toward the first roller 71 side and the second roller 72 side, respectively, while being in contact with the first surface of the optical laminated film 1. Can be made to. The curl adjusting roller 8 is provided with a driving device (not shown) for moving the curl adjusting roller 8. Rollers such as the nip roller 61 are also provided with a drive device (not shown) for moving the rollers, if necessary.

Specifically, the curl adjusting roller 8 and the guide roller 9 are arranged in this order on the downstream side of the laminating roller 7. The guide roller 9 is a guide roller arranged immediately downstream of the curl adjusting roller 8 (hereinafter, "specific guide roller 9" is used to distinguish the guide roller 9 from other guide rollers in terms of terms. ).
The optical laminated film 1 coming out of the laminating roller 7 is bent by the curl adjusting roller 8 in the side view shown in FIG. 3, and is further brought into contact with the specific guide roller 9 and conveyed. For example, the optical laminated film 1 coming out of the laminating roller 7 is conveyed to the specific guide roller 9 while being bent at an obtuse angle by the curl adjusting roller 8 in a side view.
The specific guide roller 9 is arranged at the following positions. Normally, the optical laminated film 1 on the outlet side of the laminated roller 7 is conveyed along the tangential direction (vertical direction of the paper surface in FIG. 3) common to the first roller 71 and the second roller 72. The specific guide roller 9 is arranged so that the optical laminated film 1 can be conveyed along a direction inclined with respect to the tangential direction when the curl adjusting roller 8 is not arranged. For example, the specific guide roller 9 is arranged at a position where the transport path of the optical laminated film 1 is inclined toward the second roller 72 side when the curl adjustment roller 8 is not arranged.

Since the curl adjusting roller 8 and the specific guide roller 9 are provided on the downstream side of the laminating roller 7, the curl adjusting roller 8 is displaced so that the transport path of the optical laminated film 1 is set on the first roller 71 side and the first roller 71. It can be changed to the 2 roller 72 side respectively.
In FIG. 3, the curl adjusting roller 8 is arranged so that the transport path of the optical laminated film 1 on the exit side of the laminate roller 7 is in the tangential direction (vertical direction of the paper surface) common to the first roller 71 and the second roller 72. It shows the state of being located. The position of the curl adjustment roller 8 is called the home position. The tangents refer to the tangents of the first roller 71 and the second roller 72 at the points where the optical laminated film 1 is in point contact with the first roller 71 and the second roller 72, and the two tangents are common. do.
From this home position, the curl adjustment roller 8 is moved to the optical laminated film 1 side (left side of the paper surface). Then, as shown in FIG. 4, the optical laminated film 1 is pushed out to the first roller 71 side, and the transport path of the optical laminated film 1 is displaced to the first roller 71 side.
On the other hand, the curl adjusting roller 8 is moved from the home position to the side away from the optical laminated film 1 (on the right side of the paper surface). Then, as shown in FIG. 6, the optical laminated film 1 is attracted to the second roller 72 side, and the transport path of the optical laminated film 1 is displaced to the second roller 72 side.

On the downstream side of the specific guide roller 9, a winding portion 51 for winding the optical laminated film 1 having the curl adjusted is provided.

In the manufacturing apparatus 5 of the present invention, the optical film 2 of the optical laminated film 1 is placed on the first surface side (the first surface is the surface on which the adhesive layer 3 is not provided as described above) by the curl adjusting roller 8. The curl can be adjusted to be convex, the curl can be adjusted to be convex on the second surface side (the second surface is the surface on which the adhesive layer 3 is provided as described above), or flat.
The two types of curls and flats will be described with reference to FIGS. 8A to 8C.
FIG. 8A shows an optical laminated film 1 with a curl that makes the first surface 2a side convex in the longitudinal direction, and FIG. 8B shows the second surface 2b side that is convex in the longitudinal direction. The optical laminated film 1 in the state of being curled is shown, and FIG. 3C shows the optical laminated film 1 in the state of being flat in the longitudinal direction.
Hereinafter, the curl in the state of FIG. 8 (a) is referred to as "convex curl", the optical laminated film 1 in the state of FIG. 8 (a) is referred to as "convex curl film", and the curl in the state of FIG. 8 (b) is referred to as "convex curl film". The optical laminated film 1 in the state of FIG. 8 (b) is referred to as a "concave curl film", and the optical laminated film 1 in the state of FIG. 8 (c) is referred to as a "flat film".

The above three states can be confirmed as follows.
For example, a sample S having a predetermined shape (for example, a square shape having a length of 15 cm in the longitudinal direction and a length of 15 cm in the width direction) is cut out from the optical laminated film 1 after curl adjustment, and as shown in FIG. 9, a flat surface. Place on a table with F. Then, the state (curl or flat) of the sample S is confirmed by any of the following methods (a) to (c). (A) The state (curl or flat) of the sample S is confirmed by visually observing the sample S from the side surface direction. (B) As shown in FIG. 9, the distance D between the end of the sample S and the flat surface F is determined. The state of the sample S is confirmed by measuring with a ruler. (C) The state of the sample S is confirmed from the image of the sample S taken from the side surface by an imaging means such as a camera.
In the present invention, the state (curl or flat) of the optical film 2 is adjusted, but the separator film 4 does not affect the state of the optical film 2. Therefore, checking the state of the optical laminated film 1 (optical film 2 / adhesive layer 3 / separator film 4) as described above is substantially equivalent to checking the state of the optical film 2.

[Operation of optical laminated film manufacturing equipment and curl adjustment method]
The method for producing an optical laminated film of the present invention is a step of transporting the optical film and the separator film to a laminating roller having the first roller and the second roller, respectively, and the laminating roller adheres the optical film and the separator film to the adhesive. The present invention includes a step of obtaining an optical laminated film by laminating through an agent layer, and a step of adjusting the curl of the optical laminated film by a curl adjusting roller arranged on the outlet side of the laminating roller. While the curl adjusting roller is in contact with the first surface of the optical laminated film, the transport path of the optical laminated film on the exit side of the laminated roller is displaced to the first roller side and the second roller side, respectively. The optical laminated film can be adjusted to a desired curled state and a flat state.

With reference to FIG. 3, a long strip-shaped original fabric 1A composed of an optical film 2, an adhesive layer 3 and a separator film 4 is supplied to the nip roller 61.
Usually, in order to reduce the amount of waste of the optical film 2 and the like, a so-called dummy film (not shown) is attached to each tip side of the optical film 2 and the separator film 4 of the original fabric 1A. At the initial stage of production, the optical film 2 and the separator film 4 are conveyed into the apparatus by passing each dummy film through a nip roller 61 or the like and attaching the film to the winding portion.
In the basic description of the optical laminated film manufacturing apparatus and the optical laminated film manufacturing method including curl adjustment, it is assumed that the optical film 2 included in the original fabric 1A is a flat film.
The state of the optical film 2 contained in the original fabric 1A can be confirmed to be convex curl, concave curl or flat by taking a small sample from the original fabric 1A and examining the optical film 2 of the sample.
Regarding the confirmation of the state of the optical film 2 of the original fabric 1A, the sample S may be cut out from the original fabric 1A and placed on the flat surface F in the same manner as described above.

After passing through the nip roller 61, the original fabric 1A is separated into an optical film 2 having an adhesive layer 3 and a separator film 4. The optical film 2 is conveyed to the laminating roller 7 by the optical film conveying unit 62. The separator film 4 is conveyed to the laminating roller 7 by the separator conveying unit 64. In order to illustrate the transport state of the optical film 2 and the like, FIG. 3 includes a film enlargement of a portion surrounded by a thin broken line.

The separator film 4 and the optical film 2 are sandwiched between the first roller 71 and the second roller 72 of the laminate roller 7, so that the optical laminate film 1 is discharged from the laminate roller 7.
The long strip-shaped optical laminated film 1 composed of the optical film 2 / the adhesive layer 3 / the separator film 4 passes through the curl adjusting roller 8 and the specific guide roller 9 and is wound around the winding portion 51.

As shown in FIG. 3, when the curl adjusting roller 8 is in the home position, the feed amount of the optical film 2 and the feed amount of the separator film 4 to the laminate roller 7 are the same.
Further, when the curl adjusting roller 8 is in the home position, the optical laminated film 1 coming out of the laminating roller 7 is not close to either side of the first roller 71 or the second roller 72. Therefore, the optical laminated film 1 is in point contact with the first roller 71 and the second roller 72 on the outlet side of the laminate roller 7. In this case, the transport path of the optical laminated film 1 between the laminating roller 7 and the curl adjusting roller 8 is substantially parallel to the tangential direction common to the first roller 71 and the second roller 72. In the home position, the optical film 2 is not curled, and when the optical film 2 of the original fabric 1A is a flat film, the optical laminated film 1 in a flat state can be obtained.

<Give concave curl>
Next, when applying concave curl to the optical film 2, the curl adjusting roller 8 is moved to the optical laminated film 1 side as shown in FIGS. 4 and 5. In FIGS. 4 and 5, the moving direction of the curl adjusting roller 8 is indicated by a thick arrow.
When the curl adjusting roller 8 is moved to the optical laminated film 1 side, the transport path of the optical laminated film 1 between the laminating roller 7 and the curl adjusting roller 8 is displaced toward the first roller 71 side. When the transport path is changed to the first roller 71 side, the optical laminated film 1 coming out of the laminate roller 7 is transported to the curl adjustment roller 8 while being in contact with the peripheral surface of the first roller 71. Since the separator film 4 faces the first roller 71 side, the separator film 4 is conveyed in contact with the peripheral surface of the first roller 71 on the outlet side of the laminate roller 7. As shown in FIG. 5, since the optical film 2 passes outside the first roller 71 with respect to the separator film 4, the length of the optical film 2 between the laminating roller 7 (first roller 71) and the curl adjusting roller 8 is , It becomes larger than the length of the separator film 4 in the same period. Since the laminate roller 7 is not tension-cut, it is possible to prevent excessive tension from being applied to the film when there is a difference in length between the films 2 and 4 between the laminate roller 7 and the curl adjustment roller 8.

The feed adjusting unit of the separator transport unit 64 adjusts the feed amount of the separator film 4 according to the length difference between the two films 2 and 4. The feed adjusting unit reduces the feed amount of the separator film 4 to be smaller than the feed amount of the optical film 2 when the transport path of the optical laminated film 1 is displaced toward the first roller 71 side. That is, as shown in FIG. 4, when the transport path of the optical laminated film 1 is displaced toward the first roller 71, the dancer roller 642 is lowered, so that the feed amount of the separator film 4 is reduced. Even if the curl adjusting roller 8 is moved, the amount of the separator film 4 sent to the laminating roller 7 is reduced, and as a result, it is possible to prevent the film from being excessively loosened.
When the curl adjusting roller 8 is moved to the optical laminated film 1 side in this way, when the optical film 2 of the original fabric 1A is a flat film, the optical laminated film 1 (optical film 2) with concave curl is obtained. Be done.

<Convex curl addition>
On the other hand, when applying convex curl to the optical film 2, the curl adjusting roller 8 is moved to the opposite side of the optical laminated film 1 as shown in FIGS. 6 and 7. In FIGS. 6 and 7, the moving direction of the curl adjusting roller 8 is indicated by a thick arrow.
When the curl adjusting roller 8 is moved away from the first roller 71, the transport path of the optical laminated film 1 between the laminating roller 7 and the curl adjusting roller 8 is displaced toward the second roller 72 side. When the transport path is changed to the second roller 72 side, the optical laminated film 1 coming out of the laminate roller 7 is transported to the curl adjustment roller 8 while being in contact with the peripheral surface of the second roller 72 in large quantities. Since the optical film 2 faces the second roller 72 side, the optical film 2 is conveyed in contact with the peripheral surface of the second roller 72 on the outlet side of the laminate roller 7. As shown in FIG. 7, since the separator film 4 passes outside the second roller 72 with respect to the optical film 2, the length of the separator film 4 between the laminating roller 7 (second roller 71) and the curl adjusting roller 8 is , It becomes larger than the length of the optical film 2 in the same period. Since the laminate roller 7 is not tension-cut, it is possible to prevent excessive tension from being applied to the film when there is a difference in length between the films 2 and 4 between the laminate roller 7 and the curl adjustment roller 8.

The feed adjusting unit of the separator transport unit 64 adjusts the feed amount of the separator film 4 according to the length difference between the two films 2 and 4. When the transport path of the optical laminated film 1 is displaced toward the second roller 72, the feed adjusting unit increases the feed amount of the separator film 4 to be larger than the feed amount of the optical film 2. That is, as shown in FIG. 6, when the transport path of the optical laminated film 1 is displaced toward the second roller 72, the pendulum roller 643 swings and the dancer roller 642 rises, so that the separator film 4 is fed. The amount will increase. Even if the curl adjusting roller 8 is moved, as a result of increasing the number of separator films 4 sent to the laminating roller 7, it is possible to prevent excessive tension from being applied to the film.
When the curl adjusting roller 8 is moved away from the first roller 71 in this way, when the optical film 2 of the original fabric 1A is a flat film, the optical laminated film 1 (optical film 2) having a convex curl. Is obtained.

By using the manufacturing apparatus 5 of the present invention, an optical film 2 selected from a convex curl film, a concave curl film and a flat film can be arbitrarily manufactured.
In the above, the case where the optical film 2 of the original fabric 1A is a flat film has been described, but even when the optical film 2 of the original fabric 1A is a concave curl film or a convex curl film, it can be adjusted to a desired curl.
For example, when the original fabric 1A is a concave curl film, when the transport path of the optical laminated film 1 is displaced according to the above <convex curl addition>, the optical laminated film 1 (optical film) becomes a flat film or a convex curl film. 2) is obtained. By appropriately adjusting the amount of movement of the curl adjusting roller 8, when the original fabric 1A is a concave curl film, it is possible to obtain an optical laminated film 1 (optical film 2) having a gentler concave curl. Is.
Further, when the original fabric 1A is a convex curl film, when the transport path of the optical laminated film 1 is displaced according to the above <concave curl addition>, the optical laminated film 1 (optical film) becomes a flat film or a concave curl film. 2) is obtained. By appropriately adjusting the amount of movement of the curl adjustment roller 8, when the original fabric 1A is a convex curl film, it is possible to obtain an optical laminated film 1 (optical film 2) having a gentler convex curl. Is.

The manufacturing apparatus 5 is provided with a feed adjusting unit for adjusting the feed amount of the separator film 4 to the laminate roller 7, but instead of or in combination with this, the optical film 2 is provided with a feed adjusting unit. The manufacturing apparatus 5 may be provided with a feed adjusting unit for adjusting the feed amount to the laminate roller 7.

1 Optical laminated film 2 Optical film 3 Adhesive layer 4 Separator film 5 Manufacturing equipment 62, 64 Conveyor device 642 Feed adjustment unit 7 Laminate roller 71 1st roller 72 2nd roller 8 Curl adjustment roller 9 Placed on the downstream side of the curl adjustment roller Guide roll

Claims (10)

In an apparatus for producing an optical laminated film having an optical film having an adhesive layer and a separator film bonded to the optical film via the adhesive layer.
A transport device that transports the optical film and the separator film to the laminating rollers, respectively.
The laminate roller having the first roller and the second roller forming the optical laminate film by bonding the optical film and the separator film via the adhesive layer, and the laminate roller.
It has a curl adjusting roller which is arranged on the outlet side of the laminated roller and adjusts the curl of the optical laminated film.
While the curl adjusting roller is in contact with the first surface of the optical laminated film, the transport path of the optical laminated film on the exit side of the laminated roller can be displaced to the first roller side and the second roller side, respectively. , Optical laminated film manufacturing equipment. The apparatus for producing an optical laminated film according to claim 1, wherein the laminating roller sandwiches the optical film and the separator film and adheres the two films without tension cutting. The apparatus for producing an optical laminated film according to claim 1 or 2, wherein the transport device has a feed adjusting unit for adjusting a feed amount of either one of the optical film and the separator film to the laminate roller. A guide roller is further provided on the downstream side of the curl adjustment roller.
The optical laminated film according to any one of claims 1 to 3, wherein the optical laminated film emitted from the laminated roller is bent by the curl adjusting roller and conveyed in contact with the guide roller in a side view. manufacturing device. The apparatus for manufacturing an optical laminated film according to any one of claims 1 to 4, wherein the second surface opposite to the first surface of the optical laminated film in contact with the curl adjusting roller is free. The apparatus for producing an optical laminated film according to any one of claims 1 to 5, wherein the optical film contains a polarizer. The claim that the curl adjusting roller adjusts the optical film of the optical laminated film to any one of a curl having a convex first surface side, a curl having a convex second surface side, and a flat state. The apparatus for producing an optical laminated film according to any one of 1 to 6. A process of transporting an optical film and a separator film to a laminate roller having a first roller and a second roller, respectively.
A step of passing the optical film and the separator film between the first roller and the second roller, and laminating the optical film and the separator film via an adhesive layer to obtain an optical laminated film.
It has a step of adjusting the curl of the optical laminated film by a curl adjusting roller arranged on the outlet side of the laminated roller.
Optical lamination in which the curl adjusting roller is in contact with the first surface of the optical laminate film, and the transport path of the optical laminate film on the exit side of the laminate roller is displaced to the first roller side and the second roller side, respectively. Film manufacturing method. The method for producing an optical laminated film according to claim 8, wherein the laminating roller sandwiches the optical film and the separator film and attaches the two films together without tension cutting. A guide roller is further provided on the downstream side of the curl adjustment roller.
The method for producing an optical laminated film according to claim 8 or 9, wherein the optical laminated film taken out of the laminated roller is conveyed in contact with the guide roller while being bent by the curl adjusting roller in a side view.

Images