JP2015228036A - Foreign matter removal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method that can efficiently remove a foreign matter adhering onto a film.SOLUTION: In a foreign matter removal method, a film 1 is made to pass through a non-contact type foreign matter removal device 15 and a contact type foreign matter removal device 16 in this order in foreign matter removal zones 10 and 11, each including the non-contact type foreign matter removal device 15 and the contact type foreign matter removal device 16, thereby removing a foreign matter adhering onto the film 1. The foreign matter removal zones 10 and 11 further include static eliminators 17a and 17b positioned at an upstream side of the non-contact type foreign matter removal device 15 in a conveying direction of the film 1.

Description

  The present invention relates to a method for removing foreign substances adhering to a film.

  Patent Document 1 discloses a method of obtaining a polarizing film by continuously feeding a polyvinyl alcohol-based raw film wound in a roll shape, performing various treatments while restricting the conveyance path with a plurality of guide rollers. Have been described. In the obtained polarizing film, a protective film is usually bonded to one side or both sides to form a polarizing plate. Therefore, when foreign matters such as dust and dust are adhered on the polarizing film, there is a problem that uneven marks caused by the foreign matters are formed at the time of bonding, and the yield is lowered.

  In order to solve this problem, in a manufacturing process of a film typified by an optical film such as a polarizing film, it is generally performed to remove foreign matter adhering to the film by a predetermined foreign matter removing device. . It is desirable that the removal of foreign substances adhering to the film can be efficiently performed.

JP 2010-8509 A

  The subject of this invention is providing the method which can remove the foreign material adhering on a film efficiently.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found a solution means having the following constitution and have completed the present invention.
(1) The film is passed through the non-contact type foreign matter removing device and the contact type foreign matter removing device in this order through the foreign matter removing region including the non-contact type foreign matter removing device and the contact type foreign matter removing device, and adheres on the film. A foreign matter removing method characterized by removing foreign matter.
(2) The foreign matter removing method according to (1), wherein the foreign matter removing region further includes a static eliminator located upstream of the non-contact type foreign matter removing device in the film transport direction.
(3) The foreign matter removing method according to (1) or (2), wherein the foreign matter removing region further includes a static eliminating device positioned between the non-contact foreign matter removing device and the contact foreign matter removing device. .
(4) The foreign matter removing method according to any one of (1) to (3), wherein a plurality of the foreign matter removing regions are formed.
(5) The plurality of foreign matter removal regions are located on the downstream side in the film transport direction from the first foreign matter region located corresponding to the front or back surface of the film passing through the foreign matter removal region. And a second foreign substance region positioned corresponding to the back surface or front surface of the film that passes through the foreign substance removal region.
(6) The foreign matter removing method according to any one of (1) to (5), wherein the film is an optical film.
(7) The foreign matter removal method according to any one of (1) to (6), wherein a surface activation processing device is disposed downstream of the foreign matter removal region in the film conveyance direction.
(8) The foreign matter removing method according to (7), wherein the surface activation treatment by the surface activation treatment apparatus is at least one selected from corona treatment, plasma treatment, glow treatment and ozone treatment.

  The “film” in the present invention is not limited to a film shape, and is a concept including a film shape or a sheet shape as long as the effects of the present invention are not impaired.

  According to the present invention, the foreign matter adhering to the film can be efficiently removed during film conveyance, and therefore, the process of continuously obtaining the film from which the foreign matter has been removed, and this film as another film It can use suitably with respect to the process of laminating | stacking.

It is a schematic explanatory drawing which shows the foreign material removal method concerning one Embodiment of this invention.

  The foreign matter removing method of the present invention is a method for removing foreign matter adhering to a film. As the film, a desired film that needs to remove foreign substances attached on the film can be adopted, and is not particularly limited. Examples thereof include an optical film such as a polarizing film, and a protective film for protecting the optical film. . Examples of the polarizing film include those obtained by adsorbing and orienting a dichroic dye on a polyvinyl alcohol film, and examples of the protective film include acetyl cellulose resin films such as triacetyl cellulose and diacetyl cellulose. .

  Hereinafter, with respect to one embodiment of the foreign matter removing method according to the present invention, a polarizing film is used as a film, and a protective film is pasted on the surface of the polarizing film to give a polarizing plate, with reference to FIG. Will be described in detail.

  As shown in FIG. 1, the foreign matter removing method according to the present embodiment is a method of removing foreign matter adhering to both surfaces of the polarizing film 1 while the polarizing film 1 is being transported. If it demonstrates concretely, as shown in FIG. 1, the conveyance path | route of the polarizing film 1 is controlled by the some guide roll 2. As shown in FIG. The polarizing film 1 is conveyed in the conveyance direction shown by arrow A along this conveyance path.

  In this embodiment, the 1st foreign material removal area | region 10 and the 2nd foreign material removal area | region 11 are formed in this order along the conveyance path | route of the polarizing film 1. FIG. Among these foreign matter removal regions, the first foreign matter removal region 10 is located corresponding to the surface of the polarizing film 1 that passes through the foreign matter removal region, and is a region that removes foreign matter adhering to the surface of the polarizing film 1. It is.

  The first foreign matter removal area 10 includes a non-contact type foreign matter removal device 15 and a contact type foreign matter removal device 16. The non-contact type foreign matter removing device 15 is configured to remove foreign matter attached to the surface of the polarizing film 1 in a non-contact manner with respect to the surface of the polarizing film 1. As such a non-contact type foreign matter removing device 15, for example, a so-called web configured such that the foreign matter is lifted by blowing ultrasonic waves or air onto the surface of the polarizing film 1, and the lifted foreign matter is sucked and removed. For example, a cleaner.

  The contact-type foreign matter removing device 16 is configured to be able to remove foreign matter that comes into contact with the surface of the polarizing film 1 and adheres to the surface of the polarizing film 1. Examples of such a contact-type foreign matter removing device 16 include an adhesive roll provided with a predetermined adhesive layer on the outer peripheral surface of the roll and configured to be rotatable while being in contact with the surface of the polarizing film 1.

  Here, the first foreign matter removing region 10 includes these foreign matter removing devices so that the contact-type foreign matter removing device 16 is located downstream of the non-contact type foreign matter removing device 15 in the transport direction of the polarizing film 1. . Therefore, in the first foreign matter removing region 10, the polarizing film 1 passes through these foreign matter removing devices in the order of the non-contact type foreign matter removing device 15 and the contact type foreign matter removing device 16. Thereby, when the polarizing film 1 first passes through the non-contact type foreign matter removing device 15, coarse foreign matters among foreign matters adhering to the surface of the polarizing film 1 are removed, and then the contact type foreign matter removing device 16 is used. When passing, the remaining fine foreign matter is removed.

  On the other hand, the first foreign matter removing region 10 is in the order opposite to the order described above for the foreign matter removing devices, that is, the non-contact type foreign matter removing device 15 is downstream of the contact type foreign matter removing device 16 in the transport direction of the polarizing film 1. In the case of including these foreign matter removing devices so as to be located in the position, the function of each foreign matter removing device cannot be fully exhibited for the following reason.

  That is, when the first foreign matter removing region 10 includes the foreign matter removing devices in the reverse order, the polarizing film 1 passes through these foreign matter removing devices in the order of the contact type foreign matter removing device 16 and the non-contact type foreign matter removing device 15. become. As a result, in the polarizing film 1, coarse foreign substances out of the foreign substances attached to the surface thereof are removed by the contact type foreign substance removing device 16.

  As described above, the contact-type foreign matter removing device 16 is configured to contact the surface of the polarizing film 1 and remove the foreign matter, so that a dent is formed on the surface of the polarizing film 1 at the time of the contact. And the yield of the polarizing film 1 will fall. Further, when an adhesive roll is employed as the contact-type foreign matter removing device 16, a large amount of foreign matter is stuck on the pressure-sensitive adhesive layer on the outer peripheral surface of the roll, so that the adhesive strength is likely to be reduced. As a result, maintenance such as cleaning and replacement of the adhesive roll becomes complicated. On the other hand, since the non-contact type foreign matter removing device 15 is not in contact with the polarizing film 1, the non-contact type foreign matter removing device 15 can easily deal with many foreign matters, has no problem of dents due to contact, and moreover than the contact type foreign matter removing device 16. Maintenance is often easy.

  Therefore, the first foreign matter removal area 10 includes these foreign matter removal devices 10 so that the contact foreign matter removal device 16 is located downstream of the non-contact type foreign matter removal device 15 in the conveyance direction of the polarizing film 1. The functions of each of the contact-type foreign matter removing device 15 and the contact-type foreign matter removing device 16 can be sufficiently exerted, and therefore foreign matters that are efficiently attached to the surface of the polarizing film 1 can be efficiently conveyed. It becomes possible to remove.

  The second foreign matter removal area 11 located on the downstream side in the conveyance direction of the polarizing film 1 with respect to the first foreign matter removal area 10 described above is located corresponding to the back surface of the polarizing film 1 that passes through the foreign matter removal area. This is a region for removing foreign substances adhering to the back surface of the polarizing film 1.

  Similar to the first foreign substance removal area 10, the second foreign substance removal area 11 is arranged so that the contact type foreign substance removal apparatus 16 is located downstream of the non-contact type foreign substance removal apparatus 15 in the transport direction of the polarizing film 1. Includes a foreign material removal device. Therefore, in the second foreign matter removal area 11, as in the first foreign matter removal area 10, the functions of each of the non-contact type foreign matter removal device 15 and the contact type foreign matter removal device 16 are sufficiently exhibited, and the polarizing film 1 is efficiently produced. It becomes possible to remove the foreign matter adhering to the back surface of the polarizing film 1 during the conveyance of the polarizing film 1. Other configurations of the second foreign matter removal area 11 are the same as those of the first foreign matter removal area 10.

  On the other hand, the optical film such as the polarizing film 1 tends to be charged with static electricity, and foreign matter tends not to be removed. Therefore, in this embodiment, each of the first and second foreign matter removal regions 10 and 11 includes the static elimination devices 17a and 17b that are located on the upstream side in the transport direction of the polarizing film 1 with respect to the non-contact type foreign matter removal device 15. In addition, include. Thereby, the static electricity charged in the polarizing film 1 can be removed, and the foreign matter can be removed smoothly by the non-contact type foreign matter removing device 15.

  Further, for the same reason as described in the static eliminators 17a and 17b, each of the first and second foreign matter removal regions 10 and 11 is located between the non-contact type foreign matter removal device 15 and the contact type foreign matter removal device 16. In addition, static elimination devices 17c and 17d are further included. Thereby, the removal of the foreign material by the contact-type foreign material removal apparatus 16 can be performed smoothly.

  The surface of the polarizing film 1 is often activated. In the present embodiment, the surface activation processing device 3 is disposed on the downstream side in the transport direction of the polarizing film 1 with respect to the second foreign matter removal area 11. Thereby, since the activation process can be performed on the surface of the polarizing film 1 from which the foreign matter has been removed, the activation process can be performed in an environment that is hardly affected by the foreign matter. The surface activation treatment by the surface activation treatment device 3 is preferably at least one selected from corona treatment, plasma treatment, glow treatment and ozone treatment.

  The polarizing film 1 whose surface has been activated is taken up in the direction of arrow C after the protective film 4 conveyed along the direction of arrow B is bonded to the surface by a pair of upper and lower bonding rolls 5a and 5b. Thus, the polarizing plate 6 is obtained. At this time, since the foreign matter adhering to both surfaces of the polarizing film 1 is removed by passing through the first foreign matter removal region 10 and the second foreign matter removal region 11, the uneven shape caused by the foreign matter at the time of bonding. Can be prevented from being formed on the polarizing plate 6.

  In addition, also about the protective film 4, you may make it form the 1st foreign material removal area | region 10 and the 2nd foreign material removal area | region 11 along the conveyance path | route, and remove the foreign material adhering to both surfaces. Moreover, although the layer structure of the polarizing plate 6 described above is a two-layer structure in which the protective film 4 is bonded to the surface of the polarizing film 1, the protective film 4 is bonded to the back surface of the polarizing film 1 and three layers are formed. It is good also as a structure. Bonding of the polarizing film 1 and the protective film 4 can be performed using, for example, an adhesive, a pressure-sensitive adhesive (pressure-sensitive pressure-sensitive adhesive), and the like, and is not particularly limited.

  As mentioned above, although preferred embodiment concerning this invention was described, it cannot be overemphasized that this invention can be made arbitrary, unless it deviates from the summary of this invention, and is not limited to embodiment mentioned above.

  For example, in the above-described embodiment, the first foreign matter removal region 10 and the second foreign matter removal region 11 are formed in this order along the conveyance path of the polarizing film 1, and foreign matters are removed in the order of the front surface and the back surface of the polarizing film 1. Although the case has been described, this order may be reversed in the order of the second foreign matter removal region 11 and the first foreign matter removal region 10, and the foreign matter may be removed in the order of the back surface and the front surface of the polarizing film 1.

  Moreover, when the conveyance path | route of the polarizing film 1 is long, or when it is in the environment where a foreign material tends to adhere, you may form the 1st foreign material removal area | region 10 and the 2nd foreign material removal area | region 11 in multiple numbers. The foreign matter removal region is not limited to the combination of the first foreign matter removal region 10 and the second foreign matter removal region 11, and may be only one of them.

  Moreover, although one Embodiment mentioned above demonstrated the case where the polarizing film 1 was used for a film, this invention has the same effect also with respect to the other film which needs the removal of the foreign material adhering on a film. Can do.

DESCRIPTION OF SYMBOLS 1 Polarizing film 2 Guide roll 3 Surface activation processing apparatus 4 Protective film 5a, 5b Bonding roll 6 Polarizing plate 10 First foreign substance removal area 11 Second foreign substance removal area 15 Non-contact type foreign substance removal apparatus 16 Contact type foreign substance removal apparatus 17a , 17b, 17c, 17d

Claims (8)

  The film is passed through the non-contact type foreign matter removing device and the contact type foreign matter removing device in this order through the foreign matter removing region including the non-contact type foreign matter removing device and the contact type foreign matter removing device, and adheres on the film. A foreign matter removing method characterized by removing foreign matter.   The foreign matter removing method according to claim 1, wherein the foreign matter removing region further includes a static eliminator located upstream of the non-contact type foreign matter removing device in the film transport direction.   The foreign matter removing method according to claim 1, wherein the foreign matter removing region further includes a static eliminator located between the non-contact type foreign matter removing device and the contact type foreign matter removing device.   The foreign matter removal method according to claim 1, wherein a plurality of foreign matter removal regions are formed. The plurality of foreign matter removal areas are:
A first foreign matter region located corresponding to the front or back surface of the film passing through the foreign matter removal region;
5. A second foreign matter region positioned downstream of the first foreign matter region in the film transport direction and located corresponding to the back surface or front surface of the film passing through the foreign matter removal region. Foreign matter removal method.   The foreign matter removing method according to claim 1, wherein the film is an optical film.   The foreign matter removal method according to any one of claims 1 to 6, wherein a surface activation processing device is disposed downstream of the foreign matter removal region in the film conveyance direction. The foreign matter removing method according to claim 7, wherein the surface activation treatment by the surface activation treatment apparatus is at least one selected from corona treatment, plasma treatment, glow treatment, and ozone treatment.

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