JPH04231185A - Method and device for selectively removing metallic thin film of metallized film - Google Patents

Abstract

PURPOSE:To selectively remove the metallic thin film by irradiating the laser beam on the metallized film running while being wound on the rotating metallic drum. CONSTITUTION:The metallic thin film is removed selectively by winding the metallized film 7a whose thin film surface is made to the outer side on the circular column like metallic drum 1 having the roughness <=0.4S of the front surface and being rotationable, and irradiating the laser beam 8 while running to the metallized film 7a running on the drum. Therefore, for example, the metallized film of the thickness <=1.2mum being set the non-metallic belt of extra fine width <=0.2mm width which is required for manufacturing the extra small size film capacitor can be easily manufactured.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a method for obtaining a metallized film from which any part of the metal thin film is removed, which is necessary when manufacturing film capacitors, etc. The present invention relates to a method and apparatus for removing the same.

0002

[Prior Art] A method for obtaining a metallized film from which any part of a thin metal film has been removed is to mask the film with tape or oil before metallizing it. However, there is a problem in that precise processing such as obtaining a non-metalized band with a width of 0.2 mm or less cannot be performed.

[0003] Recently, several methods have also been developed in which a film is metallized and then unnecessary portions are removed. Examples include removal by electric discharge as shown in Japanese Patent Application Laid-Open No. 59-103,324, and removal by irradiation with laser light as shown in U.S. Pat. No. 4,533,813. There are various methods, but the thickness is 1.
When attempting to remove a thin metal film formed on an ultra-thin film of 2 μm or less, or somewhat thicker but not heat resistant, damage to the film due to discharge or laser energy is unavoidable, resulting in deformation and holes in the film due to melting. Problems such as opening and even breaking occurred.

0004

[Problems to be Solved by the Invention] The present invention enables precise processing without damaging the film even when the film is extremely thin or has no heat resistance. An object of the present invention is to provide a method and an apparatus for selectively removing a metal thin film of a metallized film.

[0005]

[Means for Solving the Problems] In order to solve the above problems, the present invention improves a method of selectively removing a metal thin film by irradiating a metallized film with a laser beam that enables precise processing, and The inventors completed the invention by discovering that the problem of light irradiation can be solved by holding a metalized film on a drum and optimizing the surface condition of the drum.

That is, the present invention provides the following features: (1) A metallized film having a metal thin film formed on at least one side is attached to a rotatable cylindrical metal drum having a surface roughness of 0.4S or less. A method for selectively removing a metal thin film on a metallized film, the method comprising: irradiating the metallized film running on the drum with a laser beam to remove the metal thin film while the metallized film is wound on the outside and traveling.

(2) A metal thin film removal device consisting of a metal drum whose surface has a roughness of 0.4S or less, a laser light source and a laser beam concentrator for removing the metal thin film on the drum, and a metallization 1. An apparatus for selectively removing a metal thin film from a metallized film, comprising a film running device for running the film while being wound around the metal drum.

[0008]

[0009] In the present invention, a metallized film (hereinafter referred to as
A plastic film (sometimes simply referred to as a film) is a plastic film with a thin metal film formed on at least one surface. The method for forming the metal thin film includes vacuum evaporation method,
Examples include sputtering method and ion plating method. Further, aluminum, copper, nickel, zinc, etc. are used as the metal for forming the metal thin film.

[0010] The thickness of the metal thin film is preferably 100 angstroms or more and 2000 angstroms or less.

[0011] Also, what is meant by plastic film here?
Polyethylene film, polypropylene film, polyethylene terephthalate film, polyphenylene sulfide film, polyarylate film, polyethylene naphthalate film, polycarbonate film,
Films whose main component is organic polymers, such as polyetherimide film, polyetheretherketone film, and nylon film. Among these, the effects of the present invention are great when the film is made of a thermoplastic resin composition, particularly biaxially oriented polypropylene film, biaxially oriented polyethylene terephthalate film,
The effect is great when using biaxially oriented polyethylene naphthalate film or biaxially oriented polyphenylene sulfide film.

[0012] The thickness of the plastic film is 0.5
The effect of the present invention is large when the diameter is not less than μm and not more than 3.5 μm.
In the case of a film made of a thermoplastic resin composition with a melting point exceeding 250 ° C., when it is 0.5 μm or more and 1.2 μm or less,
Especially effective.

[0013] In the method of selectively removing a metal thin film of a metallized film of the present invention, the back side of the metallized film,
That is, the surface roughness Ra of the surface opposite to the surface from which the metal thin film is to be selectively removed is 0.003 μm or more and 0.08 μm.
It is preferable that it is below. If Ra is less than 0.003 μm, it will be difficult to remove wrinkles that occur when winding the film around a drum, making precise processing difficult, and if Ra is greater than 0.08 μm, it will be difficult to irradiate with laser light. Sometimes the film becomes susceptible to damage.

The present invention provides a method and an apparatus for removing the metal thin film while winding such a metallized film around a metal drum with the surface on which the metal thin film is formed facing outward and running the film.

[0015] In the present invention, the metal drum (hereinafter sometimes simply referred to as drum) is a rotatable cylindrical metal drum, and is also called a metal roll or metal roller.

[0016] The term "made of metal" as used herein means that at least the portion that comes into contact with the metallized film (the outer peripheral portion of the drum) is made of metal. Unless the part is made of metal, damage to the film caused by laser light cannot be suppressed.

[0017] It is preferable that the diameter of the drum is 150 mm or more, since it is easy to convey the film to an accurate position. Furthermore, although any method may be used to run the film, it is preferable that the drum be driven, since this makes it easier to run the film at an accurate speed.

In the present invention, it is necessary to give the surface of the drum a mirror finish with a roughness of 0.4S or less. Preferably it is 0.3S or less, more preferably 0.2S or less.

[0019] Furthermore, it is preferable to cool the temperature of the drum surface to 5°C or less. Methods for cooling the drum surface include a method of circulating a refrigerant inside the drum, and a method of cooling the drum surface by blowing cold air from the outside.

[0020] Here, the surface of the drum refers to the surface of the drum that comes into contact with the metallized film. By creating such a mirror surface or by cooling the surface, damage to the film caused by laser light can be suppressed.

[0021] The present invention provides the above-mentioned metal drum with
A method and an apparatus for selectively removing a thin metal film of a metalized film running by a film running device for running the metalized film while being wound around the metal drum using a laser beam.

Here, "wrapping" means that the metallized film from which the metal thin film is to be removed is in close contact with at least a portion of the outer peripheral surface of the metal drum.

[0023] Adhesion means that the metallized film does not slip on the drum surface, and a common method for making the metallized film adhere to the drum is to apply tension to the metallized film and wind it around the drum. However, when you want to reduce the tension as much as possible, such as when the metallized film is thin, you can apply an electric charge to the metallized film and make it adhere with static electricity.
It is also possible to adopt or use a method in which a liquid such as water is interposed between the metallized film and the drum to bring them into close contact.

[0024]Film running devices include rolls, drums, film winding devices, etc. driven by power.
A device that can move the film at a desired speed in the longitudinal direction of the film.

[0025] As the technique for removing the metal thin film using laser light, known techniques can be applied as they are. In other words, a laser light source and a condensing device that condenses the light beam emitted from the light source onto the metal thin film of the metallized film are essential requirements, and a laser beam splitting device, a film position detection device, and a condensing device movement are required as necessary. Mechanisms can be combined.

A YAG laser is generally used as a laser light source, and the necessary energy can be obtained by combining this with a Q switch. Further, a carbon dioxide laser, a semiconductor laser, an excimer laser, etc. can also be used as a light source.

The light beam emitted from such a light source is focused on the metal thin film portion of the metallized film by a condensing device to remove the metal thin film.

At this time, if the laser beam is fixed and the film is run, a band-shaped non-metalized portion running in the longitudinal direction of the film can be formed. In addition, if the position of the laser beam is periodically moved in the width direction of the film, or if the laser beam is irradiated intermittently and then stopped repeatedly, the non-metalized band may move periodically or the non-metalized band may be discontinuous. A banded metallized film can be obtained. Further, by moving the position of the laser beam back and forth and left and right, it is possible to obtain a metallized film in which a non-metalized portion is formed in an arbitrary shape.

[0029]

[Examples] The present invention will be specifically explained below with reference to Examples.

Embodiment FIG. 1 shows a schematic diagram of an apparatus according to one embodiment of the invention. Here, a film unwinding device 2 that supplies an unprocessed metallized film 7a and a film winding device that winds a processed metallized film 7b sandwiching a metal drum 1, which is an important component of the present invention. 3 is shown. The film unwinding device 2 and the film winding device 3 are capable of performing other steps before and/or after the step of selectively removing a metal thin film using a laser beam according to the present invention. It can be replaced with the equipment to be implemented.

[0031] Here, the metal drum 1 is driven in a speed controllable manner, and the film unwinding device 2 and film winding device 3 are driven by a servo motor (
(not shown) are connected to constitute a film transport device.

In FIG. 1, the surface of a metal drum 1 made of iron is plated with chrome over the entire circumference and has a mirror finish with a roughness of 0.2S. Drum diameter is 600mm, width 10
It is 0mm.

Further, the laser light source 4 is a YAG laser (
200W) and is combined with a Q switch (10kHz) to obtain a pulse wave. The light beam emitted from the light source passes through a half mirror 5a, a total reflection mirror 5b,
After passing through a beam splitting device consisting of a total reflection mirror 5c,
It is guided by a light concentrator 6 and reaches the surface of the metallized film conveyed on the drum 1. Note that the four condensing devices 6 in the figure are arranged at equal distances in the width direction of the metallized film.

The metallized film was a polyethylene terephthalate film with a thickness of 0.9 μm, with aluminum vapor-deposited on the entire surface of one side to a thickness of 250 angstroms, and was slit to a width of 75 mm. The surface roughness Ra of the non-metalized surface of this metalized film is 0
．． It was 03 μm.

This metallized film was passed through the apparatus shown in FIG. 1 and irradiated with laser light while traveling at 100 m/min. By adjusting the power of the laser beam, it was possible to obtain a metallized film in which continuous non-metalized bands with an average width of 0.15 mm were formed.

Comparative Example The drum of the apparatus shown in FIG. 1 was replaced with a conventional drum (the size is the same as that of Example 1, but a nonwoven fabric was pasted on the surface all around to prevent diffuse reflection of laser light). Instead, run the metallized film in the same manner as in Example 1,
irradiated with laser light. However, when the film was irradiated with laser light under the same conditions as in the example, part of the film melted due to the energy of the irradiated laser light, and a hole was formed at the center of the laser light pulse. Therefore, when the power of the laser is gradually reduced, the metal thin film is irradiated with pulses of laser light, and when the power is reduced to the point where there are no holes, the non-metalized part begins to become discontinuous while there are holes. Only the central part of the evaporated area was evaporated in spots. That is, no matter how the power of the laser beam was adjusted, it was not possible to obtain a high-quality metallized film in which continuous non-metalized bands were formed without damaging the film.

As described above, according to the present invention, the metal thin film of the metallized ultra-thin film can be selectively removed.

[0038]

[Effects of the Invention] With the above structure, the feature of the removal method using laser light, which allows for more precise, accurate, and fine processing than conventional methods, is maintained in the method of selectively removing the metal thin film of the metallized film. The metal thin film can now be removed even from metallized ultra-thin films, which could not be applied in the past because the film would be damaged by the energy of the laser beam, causing holes and breakage. The present invention enables the easy production of a metallized film having a thickness of 1.2 μm or less and provided with a non-metalized band having an extremely narrow width of 0.2 mm or less, which is required for manufacturing ultra-small film capacitors, for example. enable.

[0039]

[Operation] The present invention has a mirror finish on the surface of the drum that is in contact with the metallized film.
The contact area between the metallized film and the drum increases, and the remaining heat from the metal thin film that absorbs laser light and evaporates can be dissipated to the drum without being stored inside the film, reducing damage to the film. It is thought that this could be suppressed. The reason why thick films were not damaged in the past is thought to be because residual heat could be dispersed in the thickness direction of the film.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an apparatus according to Example 1 of the present invention.

[Explanation of symbols]

1... Metal drum 2... Metallized film unwinding device 3...
Metallized film winding device 4... Laser light source 5a... Half mirror 5b... Total reflection mirror 5c... Total reflection mirror 6... Concentrator 7a... Metallized film (before processing) 7b...
Metallized film (after processing) 8 ... Laser beam

Claims (2)

[Claims] Claim 1: A metallized film having a metal thin film formed on at least one side is wound around a rotatable cylindrical metal drum having a surface roughness of 0.4S or less with the metal thin film surface facing outward, and the drum is run. A method for selectively removing a metal thin film of a metallized film, the method comprising: irradiating the metallized film running on the drum with a laser beam to remove the metal thin film while moving the metallized film. 2. A metal thin film removal device comprising a metal drum having a surface roughness of 0.4S or less, a laser light source and a laser beam concentrator for removing the metal thin film on the drum, and a metallized film. 1. A device for selectively removing a metal thin film from a metallized film, comprising: a film running device for running the film while being wound around the metal drum.