JP5301484B2 - Film conveying apparatus and method - Google Patents

Abstract

A film conveyance device (10, 20) is provided with a conveyance roller (14, 24) and an electrostatic generation device (16, 26). The conveyance roller (14, 24) is provided with two rings (14B, 24B). The two rings (14B, 24B) hold both ends of a film (12) in the transverse direction thereof. The electrostatic generation device (16, 26) is provided between the two rings (14B, 24B). The film (12) is first electrically charged by an electrically charging device (18, 28) and then held by the conveyance roller (14, 24). An electrostatic force (Coulomb force) acts between the electrostatic generation device (16, 26) and electric charges on the film (12). The force is an attractive force or a repulsive force and holds the transverse center of the film (12) so that the film (12) does not make contact with the conveyance roller (14, 24). The device (10, 20) does not damage the transverse center of the film (12). The device (10, 20) conveys the film (12) without contact with the transverse center of the film (12) even under vacuum.

Description

  The present invention relates to a film conveying apparatus and method, and more particularly to a film conveying apparatus and method for conveying a film in a non-contact state.

  Optical devices such as gas barrier films, protective films, optical filters, and antireflection films are used as functional films in various devices such as optical devices, display devices such as liquid crystal displays and organic EL displays, semiconductor devices, and thin film solar cells. ing. As an example of such a functional film, an organic film mainly composed of a polymer is formed on a plastic film (also simply referred to as a film), and an inorganic film made of an inorganic material is formed thereon by a vacuum film forming method. A functional film (laminate) formed as a hard thin film is known.

  Depending on the member whose surface is modified in vacuum, such as vapor deposition, sputtering, or CVD, the roller may not be able to be conveyed because it is soft or easily damaged. In such a case, the surface is usually protected by a laminate, and usually the steps of peeling the laminate immediately before the step of vapor deposition, etc., surface modification, and laminating are usually taken. However, repeating delamination and lamination for each surface modification has a problem that costs are high.

  By the way, as a method of conveying a film to a roller in a non-contact manner, for example, as disclosed in Patent Document 1, it is proposed to convey the film in a non-contact state using air pressure.

Patent No. 3956264

  However, as disclosed in Patent Document 1, a method is generally employed in which air floats under normal pressure and the film surface is conveyed in a non-contact manner, but static pressure and dynamic pressure levitation using gas cannot be used under vacuum. There was a problem. Further, even under normal pressure, the method of floating by gas pressure as in Patent Document 1 causes the dust in the transport environment to rise, and there is a problem that the dust adheres to the film.

  The present invention has been made in view of such circumstances, and provides a film transport apparatus and method that can prevent dust from adhering to the film and transport it non-contactingly to the film surface even under vacuum. The purpose is to do.

  In order to achieve the above object, the present invention provides a transport roller having a step for holding only both ends of a continuously transported film, and a static electricity generator provided at a certain distance from a film surface that is not in contact with the step. A film transporting device is provided that transports the central portion of the film in a non-contact manner to a transporting roller by a Coulomb force between the charge of the film and a static electricity generating device.

  Further, in order to achieve the above object, the present invention provides a film that is continuously conveyed by a conveying roller having a step that holds only both ends. A film conveying method is provided, wherein the film is conveyed in a non-contact manner with the conveying roller.

  The present inventor has obtained the knowledge that the problem can be solved by utilizing the Coulomb force in order to transport the film to the roller in a non-contact manner. That is, it has been discovered that the film can be continuously conveyed in a non-contact manner by repelling or adsorbing the charge on the film by a static electricity generator.

  Here, the film which concerns on this invention should just be a non-contact center part, and both ends of a film are hold | maintained at a roller. Since the static electricity generator generates electric charges in the direction of floating by the Coulomb force while holding only both ends of the film with a conveying roller having a step that holds only both ends of the film, the central part of the film continues without contacting the rollers. Be transported.

  Therefore, according to the present invention, it is possible to prevent the dust in the transport environment from flying up and sticking to the film as in the case of floating with air, and to float and transport even under vacuum.

  In the present invention, it is preferable that a charging device for charging the surface of the film facing the static electricity generator is provided upstream of the static electricity generator.

  Films usually have a certain amount of charge, but this charge is very small. Therefore, the Coulomb force may not be sufficient for a thick film or a wide film. Therefore, the present inventor has found that it is preferable to provide a discharge device for charging the surface of the film facing the static electricity generator upstream of the static electricity generator.

  By providing a discharge device for charging the surface of the film facing the static electricity generating device upstream from the static electricity generating device, the central portion of the film is preferably continuously conveyed without contacting the roller.

  Further, according to the present invention, in the charging device, positive charges and negative charges are alternately charged at an arbitrary pitch in the width direction of the film. In the static electricity generator, the charge of the film and the surface of the static electricity generator are provided. It is preferable to apply a voltage at the above-mentioned arbitrary pitch so that Coulomb forces act on each other.

  By charging the film in this way and applying a voltage to the static electricity generator, the film can be continuously conveyed without the center of the film being in contact with the roller.

  The film transport device of the present invention is preferably used under vacuum.

  Since the film cannot be lifted and conveyed by air under vacuum, the present invention is particularly effective.

  In this invention, it is preferable that the level | step difference holding the said film both ends is a ring which rotates freely independently or dependently.

  The step which holds both ends of the film is a ring, and the film can be preferably continuously conveyed by rotating independently or dependently on the conveying roller.

  In the present invention, it is preferable that a film is nipped on the ring. Or in this invention, it is preferable that the said ring surface is provided with the groove | channel. Alternatively, the ring is preferably tapered.

  Since the film is nipped on the ring, the groove surface is provided with a groove, or the ring is tapered, the holding force of the film at the end of the film is increased. The central part of the film can be conveyed without contact.

  Moreover, in this invention, it is preferable that the electrode of the said static electricity generator is 60% or more of a film width.

  By setting the electrode of the static electricity generator to 60% or more of the film width, the central portion of the film can be preferably conveyed in a non-contact manner.

  In the present invention, the Coulomb force between the charge of the film and the static electricity generator may be an attractive force or a repulsive force.

  According to the present invention, it is possible to provide a film transporting apparatus and method capable of preventing dust from adhering to a film and transporting the film surface in a non-contact manner even under vacuum.

The perspective view which shows the structure of the film conveying apparatus of 1st Embodiment. The side view and front view which show the structure of the film conveying apparatus of 1st Embodiment The perspective view which shows the structure of the film conveying apparatus of 2nd Embodiment. The side view and front view which show the structure of the film conveying apparatus of 2nd Embodiment The side view and front view which show the conveyance roller which concerns on the film conveyance apparatus of this invention The side view which shows the conveyance roller concerning the film conveyance apparatus of this invention

  Hereinafter, preferred embodiments of a film conveying apparatus and method according to the present invention will be described in detail with reference to the accompanying drawings.

  1 and 3 are perspective views showing the configuration of a film transport apparatus according to an embodiment of the present invention, and FIGS. 2 and 4 are a side view and a front view thereof, respectively.

  The film transport apparatus 10 according to the first embodiment uses repulsion of electrostatic force (Coulomb force), and the film repulsive force between the charge of the film 12 and the charge generated by the static electricity generator 16 causes the film to move. The center part of 12 is conveyed to the conveyance roller 14 in a non-contact manner.

  1 and 2 show a film transport apparatus 10 according to the first embodiment, which mainly includes a transport roller 14 and a static electricity generator 16.

  The transport roller 14 is provided with a step for holding only both ends of the film 12 that is continuously transported. The static electricity generator 16 is provided on an axis between the steps of the transport roller 14.

  Further, the film transport apparatus 10 shown in FIG. 1 is provided with a charging device 18 for charging the surface of the film facing the static electricity generation device 16 upstream of the static electricity generation device 16. The electrification charge to the film 12 in the charging device 18 can be arbitrarily selected, but FIG. 1 is a diagram in which positive and negative charges are discharged at a certain pitch in the film width direction to charge the film surface. Is shown.

  The static electricity generator 16 generates a charge on the shaft of the transport roller 14 so as to repel the charge charged on the film 12. Thereby, the charge of the film 12 and the charge generated in the static electricity generator 16 are repelled. Since both ends of the film 12 are held by the step of the conveying roller 14, the flying height of the film is defined thereby.

  That is, since the repulsive force is half proportional to the square of the distance, even if the film is slightly deformed and approaches the static electricity generating device 16 on the conveying roller, the repulsive force becomes strong and the central portion of the film is difficult to contact the conveying roller.

  With the film transport apparatus 10 having the above-described configuration, the central portion of the film 12 can be continuously transported to the transport roller 14 without contact. Therefore, the film can be transported without damaging the surface of the film.

  Under normal pressure, a method is generally used in which air floats and transports the film surface in a non-contact manner, but there is a problem that static pressure and dynamic pressure surfacing using gas cannot be used under vacuum. Further, even under normal pressure, there is a problem that dust adheres to the film when it is floated by a gas pressure (air). However, according to the present invention, it is possible to prevent dust from adhering to the film and to convey it to the film surface in a non-contact manner even under vacuum.

  Since the film 12 is usually charged with a small amount of static electricity, a charge having the same polarity as the charge of the film is applied to the static electricity generator 16, and the charge of the film 12 and the charge generated in the static electricity generator 16 are With the repulsive force, the film 12 can be levitated and conveyed. That is, the charging device 18 is not essential. Further, the film transport device 10 may be provided with a static elimination device (not shown) that neutralizes charges charged on the surface of the film on the downstream side of the static electricity generation device 16.

  3 and 4 show a film transport device 20 according to the second embodiment, which mainly includes a transport roller 24 and a static electricity generator 36.

  The transport roller 24 is provided with a step for holding only both ends of the continuously transported film 12. The static electricity generator 26 is formed in an arc shape at a certain distance from the film 12 at the position of the transport roller 24.

  3 is provided with a charging device 28 for charging the surface of the film facing the static electricity generator 26 on the upstream side of the static electricity generator 26. The electrification charge to the film 12 in the charging device 28 can be arbitrarily selected, but FIG. 3 also discharges positive charges and negative charges at a constant pitch in the film width direction as in FIG. The surface is charged.

  The static electricity generator 26 generates electric charges in an arc shape along the transport roller 24 so as to be adsorbed to the electric charges charged on the film 12. Thereby, the charge of the film 12 and the charge generated in the static electricity generator 26 are adsorbed. Since both ends of the film 12 are held by the level difference of the transport roller 24, the flying height of the film is defined by this.

  Since the attractive force is proportional to the charge generated by the static electricity generator 26, if there is too much charge generated by the static electricity generator 26, the film will be attracted to the static electricity generator 26. Since both ends are held, it is necessary to apply the electric charge generated by the static electricity generator 26 so as to exert an attractive force so that the film does not contact the shaft of the transport roller 24.

  With the film transport device 20 configured as described above, the central portion of the film 12 can be continuously transported to the transport roller 24 without contact. Therefore, the film can be transported without damaging the surface of the film.

  Since the film 12 is usually charged with a small amount of static electricity, a charge having a polarity opposite to the charge of the film is applied to the static electricity generator 26, and the charge of the film 12 and the charge generated in the static electricity generator 26 are applied. The film 12 can be levitated and conveyed by the adsorbing force. That is, as in the first embodiment, the charging device 28 is not essential. In addition, the film transport device 20 may be provided with a static elimination device (not shown) that neutralizes charges charged on the surface of the film downstream of the static electricity generation device 26.

  In the present invention, the both ends of the film are conveyed while being supported by the steps of the conveying roller 14, so that the film 12 is always conveyed while maintaining a constant flying height. Thus, the film 12 can be stably conveyed without causing the above.

  Further, since the transport roller 14 (24) is rotatably supported, when the film 12 travels, the transport roller 14 (24) rotates in synchronization with the web 12 by a frictional force caused by contact with the web 12. Therefore, scratches or the like do not occur on the web 12.

  Here, as shown in FIG. 5, it is preferable that the level difference holding both ends of the film is constituted by a ring 14B (24B) that freely rotates independently or dependently.

  5A is a diagram showing that the ring 14B (24B) rotates depending on the shaft 14A (24A) of the transport roller 14 (24), and FIG. 5 (b) is a diagram illustrating the transport roller. It is the figure which showed that the ring 14B (24B) rotated independently of the axis | shaft 14A (24A) of 14 (24). The conveying roller 14 (24) in FIG. 5B is configured such that the shaft 14 A (24 A) and the ring 14 B (24 B) are rotatable via a bearing 32.

  In the present embodiment, the ring 14B (24B) that forms the step of the transport roller 14 is configured to rotate by frictional force due to contact with the film 12, but the motor 12 or the like is used to travel the film 12. You may make it rotationally drive synchronously. As a result, the web 12 can be prevented from slipping on the ring, and the occurrence of scratches and the like can be suppressed.

  In the present invention, it is preferable that both ends of the film 12 are nipped by a nip roller 34 on the ring 14B (24B) of the transport roller 14 as shown in FIG. Alternatively, in the present invention, although not shown, it is preferable that a groove is provided on the ring surface. Alternatively, the ring is preferably tapered. Since the film is nipped on the ring, a groove is provided on the ring surface, or the ring is tapered, the holding force of the film at both ends of the film is increased. The central part of the film can be conveyed without contact. The taper shape of the ring is preferably a shape in which the outer shape of the outer side in the axial direction of the transport roller 14 is large, and the taper angle is preferably in the range of 0.005 ° to 0.2 ° with respect to the shaft of the transport roller 14. If it is less than 0.005 °, the effect of increasing the holding force of the film is weak, and if it is more than 0.2 °, wrinkles are generated in the film.

  In the present invention, the width of the static electricity generator 16 (26) is preferably 60% or more of the width of the film 12. By setting the electrode of the static electricity generator to 60% or more of the film width, the central portion of the film can be preferably conveyed in a non-contact manner.

  As described above, by continuously transporting the film with the film transport apparatus of the present invention, it is possible to prevent dust from adhering to the film and transport it to the film surface in a non-contact manner even under vacuum.

  In addition, the film conveying apparatus and method concerning this invention can be used before and after the application | coating process of the optical film for liquid crystal display panels which wants to convey avoiding the contact of a film surface. In particular, since the film transport apparatus according to the present invention enables non-contact transport in a vacuum, it is preferably used before or after the film-forming process of a functional film formed as a hard thin film by a vacuum film-forming method. be able to.

  As mentioned above, although the film conveying apparatus and method of this invention were demonstrated in detail, this invention is not limited to the said embodiment, You may perform various improvement and a change in the range which does not deviate from the summary of this invention. Of course.

  DESCRIPTION OF SYMBOLS 10 ... Film conveying apparatus, 12 ... Film (web), 14 ... Conveying roller, 14A ... Shaft, 14B ... Ring, 16 ... Static electricity generator, 18 ... Charging apparatus, 20 ... Film conveying apparatus, 24 ... Conveying roller, 24A ... Shaft, 24B ... Ring, 26 ... Static electricity generator, 28 ... Charging device, 32 ... Bearing, 34 ... Nip roller

Claims (12)

A transport roller having a step for holding only both ends of the continuously transported film;
A static electricity generator provided at a certain distance from the film surface that is not in contact with the step, and
A film transporting device that transports the central portion of the film in a non-contact manner to a transporting roller by a Coulomb force between the charge of the film and the static electricity generation device.   The film transport apparatus according to claim 1, wherein a charging device that charges the surface of the film facing the static electricity generation device is provided upstream of the static electricity generation device. In the charging device, positive and negative charges are alternately charged at an arbitrary pitch in the width direction of the film,
3. The film transport apparatus according to claim 2, wherein in the static electricity generator, a voltage is applied at the arbitrary pitch so that a charge of the film and a surface of the static electricity generator act on each other. .   The film conveyance apparatus of any one of Claims 1-3 is used under a vacuum, The film conveyance apparatus characterized by the above-mentioned.   The film conveying apparatus according to claim 1, wherein the step for holding both ends of the film is a ring that freely rotates independently or dependently. The film transport device according to claim 5 , wherein a film is nipped on the ring. The film transport device according to claim 5 , wherein a groove is provided on the ring surface. The film transport apparatus according to claim 5 , wherein the ring has a tapered shape. 6. The film transport apparatus according to claim 5 , wherein an electrode of the static electricity generator is 60% or more of a film width. The film transport apparatus according to claim 1, wherein the Coulomb force between the charge of the film and the static electricity generator is an attractive force. The film transport apparatus according to claim 1, wherein a Coulomb force between the charge of the film and the static electricity generator is a repulsive force.   A film that is continuously conveyed by a conveying roller having a step that holds only both ends is conveyed in a state where the central portion of the film is not in contact with the conveying roller by a coulomb force between a film charge and a static electricity generator. Film transport method.

Images