JP2015047749A - Manufacturing method of film laminate and manufacturing equipment of film laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress intrusion of foreign substances into a film laminate, in a manufacturing method of a film laminate that manufactures a film laminate having a protective film laminated on an optical film with an adhesive layer interposed.SOLUTION: A clean room has two areas or more having higher cleanliness than other areas. Foreign substances are removed at the upstream side of the two areas arranged side by side, and a protective film is bonded at the downstream side thereof which has higher cleanliness than the upstream side.

Description

  The present invention relates to a film laminate manufacturing method and film laminate manufacturing equipment, and more specifically, a film laminate for producing a film laminate in which a protective film is laminated on the surface of an optical film via an adhesive layer. The present invention relates to a production method and production equipment for producing such a film laminate.

  Conventionally, a polarizing film (polarizing plate) is used as an optical film applied to an optical product such as an image display device.

This type of polarizing film is usually produced continuously and has a long band shape.
Then, the polarizing film is a film laminate in which the protective film is laminated on at least one surface via an adhesive layer, and further in a form called an original roll in which the film laminate is wound into a roll. Stored.
Thereafter, the raw roll is processed into a sheet piece (polarizing plate) having a predetermined shape by punching or the like, and the sheet piece is shipped as a product for incorporation into an optical product.

The original roll is not necessarily a non-defective polarizing film over the entire surface, and is a technique for detecting a defective part by applying it to an inspection device with the protective film once peeled off before the punching. It has been known.
In such a case, the punching is performed after a protective film is again laminated on the inspected polarizing film and a film laminate is newly produced.
Inspection of this kind of polarizing film and production of a film laminate are usually carried out in a clean room (see Patent Document 1 below).

JP 2009-069142 A

In producing the film laminate as described above, it is desirable that the clean room has a high degree of cleanliness in order to prevent foreign matters from entering the film laminate.
However, it is not easy to maintain the entire production equipment for film laminates at a high level of cleanliness. In the production of film laminates using conventional equipment, it is difficult to mix foreign substances into the final film laminate. It has the problem that it is difficult to suppress.

  This invention makes it a subject to solve such a problem, and makes it a subject to suppress the foreign material mixing in a film laminated body.

In addition, it is requested not only when the protective film is pasted again on the polarizing film after the inspection, but also to produce a raw roll before the inspection. The same applies to the case where a protective film is bonded to the film.
Moreover, it is desired not only when the optical film is a polarizing film but also for other optical films that the entry of foreign matter into the film laminate is desired.

The inventor locally surrounds an area where a bonding apparatus for bonding a protective film to an optical film to produce a film laminate is installed, thereby reducing the cleanliness of the area from other areas in the clean room. Focusing on the fact that it is easy to improve, the inventors have intensively studied to solve the above problems.
Then, the present inventor provides an area that is locally surrounded also in the preceding stage of the above-mentioned area, and improves the cleanliness of the preceding area (first area) as compared with other areas in the clean room. The foreign matter is removed from the optical film or the like in the first area, the degree of cleanness of the area (second area) on the rear side of the first area is further improved, and the bonding is performed in the second area. As a result, it has been found that a film laminate in which contamination of foreign matters is suppressed as compared with the conventional film laminate can be obtained, and the present invention has been completed.

  That is, the present invention relating to a method for producing a film laminate for solving the above-mentioned problems is a belt-like optical film or a belt-like film laminate in which a protective film is laminated on the surface of the optical film via an adhesive layer. The body is transported in a clean room such that the longitudinal direction is the moving direction, and two or more areas having a higher degree of cleanliness than other areas are arranged in the clean room, and the first area of the two or more areas And a second area having a higher degree of cleanliness than the first area, and the first area is disposed on the upstream side in the movement direction, and the optical film or the film laminate is Foreign matter removal for removing foreign matter from the surface of the optical film or the film laminate by carrying out the transfer so as to be supplied to the second area through the first area After carrying out the process in the first area, in the second area, a bonding process is performed in which the protective film is bonded to the optical film or the optical film after the protective film is peeled off from the film laminate. It is characterized by producing a film laminate.

  Further, the present invention according to the film laminate manufacturing equipment for solving the above problems is a clean room, a strip-shaped optical film, or a strip formed by laminating a protective film on the surface of the optical film via an adhesive layer. A transfer means for transferring the film laminate in the clean room so that the longitudinal direction thereof is the moving direction, and removing foreign matter adhering to the surface of the optical film or the film laminate being transferred by the transfer means A foreign material removing device, and a bonding device that bonds the protective film to the optical film after the protective film is peeled off from the optical film or the film laminate, and the clean room has other regions. There are two or more areas with higher cleanliness than the first area and the first area of the two or more areas. A second area having a high degree of lean is adjacent to the moving direction, and the first area is arranged on the upstream side in the moving direction, and the transfer means moves the optical film or the film laminate to the first. It is provided to be transferred to the second area through one area, the foreign substance removing device is arranged in the first area and the bonding device is arranged in the second area. It is said.

  According to the present invention, it is possible to suppress the entry of foreign matter into the film laminate.

The schematic perspective view which showed the structure of the initial stage film laminated body utilized for the manufacturing method of this invention. Schematic which showed the one aspect | mode of the equipment for enforcing the manufacturing method of this invention. Schematic which showed other embodiment of the manufacturing method of this invention. Schematic which showed other embodiment of the manufacturing method of this invention.

The preferred embodiments of the present invention will be described below.
Here, the protective film is removed from the film laminate in which the protective film is laminated on both sides of the belt-shaped polarizing film via the adhesive layer, and the polarizing film is exposed on the surface. A method for manufacturing a film laminate will be described by taking as an example a case where a protective film is again laminated on the polarizing film after optical inspection is performed and a film laminate similar to the initial film laminate is formed.

First, the structure of the film laminated body produced with the manufacturing method of this invention is demonstrated, referring FIG.
FIG. 1 shows a laminated structure of an initial film laminate (hereinafter also referred to as “initial film laminate”).
In the following, this initial film laminate will be referred to as an “initial film laminate”, and a film laminate newly produced after the inspection will be referred to as a “final film laminate” to be distinguished from each other.

As shown in FIG. 1, the initial film laminate f0 includes a long strip-shaped polarizing film fx and two protective films fy and fz for protecting both sides of the polarizing film fx.
The two protective films fy and fz in the film laminate f0 have the same shape as the polarizing film fx, and are bonded to the polarizing film fx via the adhesive layers a1 and a2, respectively.
Accordingly, the initial film laminate f0 in the present embodiment has a long strip shape in plan view similar to the polarizing film fx and is thicker than the polarizing film fx. From the top of FIG. It has a layer structure in the order of the polarizing film fx, the adhesive layer a2, and the protective film fz.

In the present embodiment, the two protective films fy and fz are both peeled from the polarizing film fx before inspection by the inspection apparatus.
More specifically, among the protective films fy and fz, the upper protective film fy is before the inspection from the surface of the adhesive layer a1 (hereinafter also referred to as “first adhesive layer a1”) between the polarizing film fx. It is peeled off.
On the other hand, the lower protective film fz becomes a protective film with adhesive layer fb with an adhesive layer a2 (hereinafter also referred to as “second adhesive layer a2”) between the polarizing film fx and polarized before inspection. It peels from the surface of the film f0.
In the following, when simply referred to as a “protective film”, it means the lower protective film fz that becomes the protective film with adhesive layer fb and is peeled off from the polarizing film fx unless otherwise specified. The upper protective film fy peeled from the surface of the first adhesive layer a1 is referred to as “first protective film fy” or “separator fy” and is distinguished from the lower protective film fz.
In the following, the lower protective film fz may be referred to as a “second protective film fz” so that the distinction becomes clearer.

Next, a first embodiment of the method for producing a film laminate will be described with reference to FIG.
First, manufacturing equipment will be described.
As shown in FIG. 2, the facility for manufacturing the final film laminate includes a clean room CR and various devices arranged in the clean room.
The manufacturing facility of the present embodiment includes a delivery machine 1 in which an original fabric roll formed by winding the initial film laminate f0 is installed in the clean room, and a product roll by winding the final film laminate f0 ′. And a winding means 6 are provided at both ends of the film laminate production line, and a transfer means for transferring the initial film laminate f0 in the clean room so that the longitudinal direction is the moving direction. The transmitter 1 and the winder 6 are configured.

The manufacturing facility has a first area A1 having a higher degree of cleanliness than the other areas in the clean room between the transmitter 1 and the winder 6 and a higher degree of cleanliness than the first area. The first area A1 and the second area A2 are adjacent to each other in the moving direction of the initial film laminate f0, and the first area A1 is disposed on the upstream side in the moving direction. doing.
That is, the manufacturing facility gradually improves the cleanliness from the area where the transmitter 1 is arranged upstream of the first area A1 to the first area A1 and the second area A2. Yes.
The transfer means in the present embodiment is configured to transfer the film laminate so that the longitudinal direction is the moving direction, and the film laminate passes through the first area A1 and the second area A2 in this order. It is configured accordingly.

The first area A1 is an area for removing foreign matter adhering to the surface of the initial film laminate f0, and the second area A2 is after the protective film is peeled from the initial film laminate f0. It is an area for bonding a protective film with respect to the polarizing film (polarizing film fa with an adhesion layer).
In the manufacturing facility according to the present embodiment, the initial film laminate f0 fed out from the transmitter 1 is transferred with the separator side facing the upper surface, and the initial film laminate f0 is in the first area. It is supplied to the second area A2 through A1, and the final film laminate f0 ′ obtained in the second area A2 is wound up by the winder 6 provided on the downstream side of the second area A2. It is configured accordingly.

The first area A1 and the second area A2 can be formed by arranging a small clean room adjacent to the inside of the clean room CR, and a method of installing such a small clean room in the clean room. Alternatively, the clean room CR can be formed by partitioning from the floor surface to the ceiling surface.
Further, when the first area A1 and the second area A2 are formed by a small clean room, the clean room may be a simple one called a so-called clean booth.

In the manufacturing facility of the present embodiment, a foreign matter removing device 2 that removes foreign matter adhering to the surface of the initial film laminate f0 transferred by the transfer means is arranged in the first area A1. Yes.
Moreover, the manufacturing equipment of this embodiment is equipped with the peeling apparatus 3, the test | inspection apparatus 4, and the bonding apparatus 5 in the said 2nd area A2 in order from the moving direction upstream of a film laminated body.

The foreign matter removing device 2 is for causing a foreign matter removing step for removing foreign matter from the surface of the initial film laminate f0 in the first area A1, and is a belt-like sheet like the film laminate in the present embodiment. Any material that can remove foreign matter adhering to the surface can be used. For example, the surface of a belt-like sheet directly compared to a type that removes foreign matter together with wind. In order to reliably remove foreign matter, a type in which the foreign matter is removed by abutting on the surface is preferable.
Therefore, in the present embodiment, the foreign matter removing device 2 including the pair of adhesive rolls 21 is disposed in the first area A1.

The pair of adhesive rolls 21 is rotatable around the rotation axis, the rotation axis is set in the horizontal direction substantially orthogonal to the transfer direction of the initial film laminate f0, and is provided in the foreign substance removal device 2 in two upper and lower stages. Yes.
The pair of the adhesive rolls 21 have a length equal to or greater than the width of the initial film laminate f0, and the upper surface (separator) and the lower surface ( The respective outer peripheral surfaces are in contact with both the protective film and the protective film.
And the said adhesive roll 21 is distribute | arranged so that it may contact | abut over the full width of the initial film laminated body f0, and is distribute | arranged so that it may be accompanied with the movement of the initial film laminated body f0.
That is, the adhering foreign matter on the surface of the initial film laminate is removed from the surface of the initial film laminate f0 in a form of being transferred to the outer peripheral surface of the rotating adhesive roll 21.

The peeling device 3 to which the initial film laminate f0 that has passed through the foreign matter removing device 2 is supplied following the foreign matter removing device 2 is configured to remove the protective film with adhesive layer fb from one side (lower surface side) of the initial film laminated body f0. A peeling process for peeling and removing the separator fy from the other surface side (upper surface side) is performed in the second area A2.
Moreover, the said inspection apparatus 4 provided in the downstream of the said peeling apparatus 3 implements the test process which test | inspects the optical characteristic of the polarizing film fa with the adhesion layer after the protective film was peeled in said 2nd area A2. In order to identify the defective part of the polarizing film.

  And the bonding apparatus 5 provided in 2nd area A2 with the peeling apparatus 3 and the test | inspection apparatus 4 is a new separator fy 'on the upper surface side of the polarizing film fa with adhesive layer after passing the said test | inspection apparatus 4. FIG. Is laminated via the first adhesive layer a1 and a bonding step of laminating a new protective film with adhesive layer fb ′ on the lower surface side of the polarizing film fa with adhesive layer is provided. The protective film is provided on both surfaces of the polarizing film fa to form the final film laminate f0 ′ having the same configuration as the initial film laminate f0.

In this embodiment, the peeling device 3 is provided on the upstream side of the inspection device 4 in order to improve the inspection accuracy of the polarizing film by the inspection device 4 by removing the protective film from both surfaces of the initial film laminate f0. However, the peeling of the protective film by the peeling device 3 does not have to be performed on both surfaces of the film laminate f0 and may be performed only on one side.
Further, if necessary, the inspection by the inspection device 4 may be performed without providing the peeling device 3 in the second area A2 while the protective film is provided on both surfaces.

Furthermore, in this embodiment, although the case where new separator fy 'and the protective film fb' with an adhesion layer are used in the bonding process by the bonding apparatus 5, as shown in FIG. 3, for example, The separator fy peeled by the peeling device 3 may be bypassed the inspection device 4 and supplied to the bonding device 5, and the bonding device 5 may bond the original surface (upper surface) again.
Further, the side of the protective film with adhesive layer fb may be bypassed the inspection device 4 and supplied to the bonding device 5, and the bonding device 5 may be bonded again to the original surface (lower surface).
Further, both the separator fy and the protective film with adhesive layer fb may be supplied to the bonding device 5 by bypassing the inspection device 4 and bonded to the original surface again by the bonding device 5. .

  In the production method of the film laminate using these production facilities, the foreign matter removal of the initial film laminate f0, the inspection of the polarizing film constituting the initial film laminate f0, and the polarizing film after the inspection The final film laminate f0 ′ can be continuously produced in parallel with the bonding of the protective film.

And in the manufacturing method of this film laminated body, 2nd area A2 in which a polarizing film is made into an exposed state can be made into a state with a high degree of cleanliness.
Accordingly, it is possible to prevent foreign matters from being mixed into the final film laminate f0 ′ while making a space for maintaining a high degree of cleanliness relatively narrow.
In addition, in the present embodiment, the first area A1 having the second highest cleanliness level is provided immediately after the second area A2, and the first area A1 corresponds to the initial film laminate f0. Foreign matter removal is performed.
Accordingly, in this embodiment, the difference in cleanliness from the previous area is reduced, and it is possible to suppress foreign substances from being brought into the second area A2 accompanying the initial film laminate f0. The removal of foreign matter in the first area A1 having a high level makes it easy to maintain the second area A2 in a state of high cleanliness without causing the foreign matter to reattach to the film laminate f0 after the removal of foreign matter, and the final film It can suppress that a foreign material mixes into laminated body f0 '.

In order to form such a gradual degree of cleanness in the clean room CR, for example, the first area A1 is set to a higher positive pressure than the other areas in the clean room, and the second area A2 is used. The positive pressure may be made higher than that in the first area A1.
That is, in the clean room for manufacturing the film laminate, for example, the positive pressure of the other area in the clean room having a relatively low cleanness relative to the first area A1 and the second area A2 is “P0”, The cleanness is “C0”, the positive pressure in the first area A1 is “P1”, the cleanness is “C1”, the positive pressure in the second area is “P2”, and the cleanness is “C2”. In this case, each environment may be adjusted so as to satisfy the following relationship.

(Positive pressure) 0 <P0 <P1 <P2
(Cleanness) Low: C0 <C1 <C2: High

Specifically, the clean room has, for example, a cleanness (C2) of the second area of class 100 or less, a cleanness (C1) of the first area of class 1000 or less, and a cleanness (C0) of other areas. Should be less than or equal to class 10,000.

  The effects as described above are also exhibited when forming the initial film laminate f0, and the manufacturing method for producing the initial film laminate f0 is also within the scope of the present invention. is there.

A method for producing a film laminate for producing the initial film laminate f0 will be described below as a second embodiment with reference to FIG.
In the second embodiment of the present invention illustrated in FIG. 4, the clean room CR has a relatively high first area A1 having a higher degree of cleanliness than other areas, and is relatively in comparison with the first area A1. In the point provided with 2nd area A2 with a high cleanliness, it is common with 1st embodiment.
The second embodiment is also the first embodiment in that the foreign matter removing device 1 is arranged in the first area A1 and the bonding device 5 is arranged in the second area A2. And in common.

On the other hand, in the first embodiment, the target for removing foreign matters in the first area A1 is the initial film laminate f0 in which a protective film is laminated on the surface of the polarizing film via an adhesive layer. The second embodiment is different from the first embodiment in that the object to be removed of foreign matter in the first area A1 is a polarizing film alone.
The second embodiment is different from the first embodiment in that the peeling device 3 is not arranged in the second area A.
In addition, in the said 2nd embodiment, the aspect which has arrange | positioned the test | inspection apparatus 4 in the 2nd area A so that the optical characteristic of the polarizing film fx can be test | inspected before formation of the initial stage film laminated body f0 is illustrated. However, if necessary, the inspection apparatus 4 may not be arranged in the second area A.

Moreover, 2nd embodiment is on the upper surface side of polarizing film fx of what is common in 1st embodiment in the point which laminates | stacks protective film fb 'with an adhesion layer on the lower surface side of polarizing film fx with the bonding apparatus 5. FIG. Unlike the first embodiment, since the adhesive layer (first adhesive layer a1) is not provided, it differs from the first embodiment in that a separator fc with an adhesive layer is stacked instead of the separator fy. ing.
That is, in the first embodiment, the separator fy is laminated via the adhesive layer present on the polarizing film, but in the second embodiment, the adhesive layer present on the separator side is provided. The separator fy is laminated on the polarizing film fx.

  The manufacturing method of the film laminated body (initial film laminated body f0) of the said embodiment transfers the long strip | belt-shaped polarizing film fx to a longitudinal direction, supplies it to the said foreign material removal apparatus 1, and passes this foreign material removal apparatus 1 The polarizing film fx thus supplied is supplied to the bonding device 5 to remove foreign matter by the foreign matter removing device 1 in the first area and to the polarizing film fx by the bonding device 5 in the second area. It can implement by the aspect which manufactures a film laminated body continuously in parallel with bonding of protective film fy and fz.

  In addition, in the above, although the manufacturing method of a film laminated body is illustrated taking the film laminated body which laminated | stacked the protective film and the separator via the adhesion layer on the polarizing film as an example, this invention is a film with a protective film etc. The optical film constituting the laminate is not limited to a polarizing film, but a film laminate is produced by laminating a protective film on a retardation film, a brightness enhancement film, or an optical film obtained by laminating these films. These are also within the scope of the present invention.

Moreover, in the above, although the aspect which forms two areas with high cleanliness is illustrated, in implementing this invention, it is relative to other areas, for example, immediately before the first area. Alternatively, an area having a high degree of cleanness and a lower degree of cleanness than the first area may be provided, and the degree of cleanness may be improved in three stages toward the second area.
Of course, the case where the cleanness is further improved by four or more stages by providing an area with a high cleanness is also within the intended range of the present invention.
Furthermore, the present invention is not limited to the above, and various modifications can be added.

  2: foreign matter removing device, 21: adhesive roll, 5: laminating device, CR: clean room, A1: first area, A2: second area, fa: polarizing film with adhesive layer, fx: polarizing film, fy: Protective film (separator), fz: protective film

Claims (6)

A belt-shaped optical film, or a belt-shaped film laminate in which a protective film is laminated on the surface of the optical film via an adhesive layer is transferred in a clean room so that the longitudinal direction is the moving direction,
In the clean room, two or more areas having a higher degree of cleanliness than other areas are arranged, a first area of the two or more areas and a second area having a higher degree of cleanliness than the first area, Is disposed adjacent to the moving direction and the first area is disposed upstream of the moving direction,
Carrying out the transfer so that the optical film or the film laminate is supplied to the second area through the first area;
After carrying out a foreign matter removing step in the first area to remove foreign matter from the surface of the optical film or the film laminate,
The film laminate is produced by carrying out a bonding step in which the protective film is bonded to the optical film after the protective film is peeled from the optical film or the film laminate in the second area. A method for producing a film laminate.   A peeling device for peeling the protective film from the film laminate after the foreign matter removing step in the second area, and an inspection device for inspecting the optical characteristics of the optical film after the protective film is peeled off by the peeling device The method for producing a film laminate according to claim 1, wherein the bonding step is performed on the optical film after the inspection by the inspection device.   2. The foreign matter removing step uses an adhesive roll and removes the foreign matter adhering to the surface by bringing the outer peripheral surface of the adhesive roll into contact with the surface of the optical film or the film laminate. The manufacturing method of the film laminated body of 2. Clean room,
A belt-shaped optical film, or transport means for transporting a belt-shaped film laminate in which a protective film is laminated on the surface of the optical film via an adhesive layer in the clean room so that the longitudinal direction is the moving direction;
A foreign matter removing device for removing foreign matter adhering to the surface of the optical film or the film laminate being transferred by the transfer means;
A bonding apparatus for bonding the protective film to the optical film after the protective film is peeled off from the optical film or the film laminate;
In the clean room, two or more areas having a higher degree of cleanliness than other areas are arranged, and a first area of the two or more areas and a second area having a higher degree of cleanliness than the first area, Are adjacent to each other in the movement direction, and the first area is arranged on the upstream side in the movement direction,
The transfer means is provided to transfer the optical film or the film laminate to the second area through the first area, and the foreign matter removing device is disposed in the first area and the sticking is performed. An apparatus for manufacturing a film laminate, wherein a combined device is disposed in the second area.   In the second area, a peeling device for peeling the protective film from the film laminate that has passed through the foreign matter removing device, and an optical characteristic of the optical film after the protective film is peeled off by the peeling device are inspected. The manufacturing apparatus of the film laminated body of Claim 4 with which the test | inspection apparatus is further provided and bonding of the protective film by the said bonding apparatus is implemented with respect to the optical film after test | inspection by this test | inspection apparatus.   The foreign matter removing device has an adhesive roll, and in the foreign matter removing device, the outer peripheral surface of the adhesive roll is brought into contact with the surface of the optical film or the film laminate to remove foreign matter attached to the surface. The manufacturing equipment of the film laminated body of Claim 4 or 5 with which is implemented.

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