JPS63488A - Method for patterning electrically conductive film - Google Patents

Abstract

PURPOSE:To make it possible to etch and wash and electrically conductive film on one side of a polymer film while moving the polymer film on a roller conveyor by sticking a protective surface film to the other side of the polymer film so as to make the polymer film hardly bendable. CONSTITUTION:A protective surface film is stuck to one side of a polymer film having an electrically conductive film on the other side so that the total thickness is regulated to >=170Xm A polyethylene film coated with an acrylic adhesive, a polyethylene film coated with a synthetic rubber adhesive or a polyester film coated with an acrylic adhesive may be used as the protective surface film.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a method for forming a pattern on a conductive film.
Specifically, the process of etching a conductor or semiconductor film made of a metal or metal compound applied to a polymer film as a substrate by vapor deposition or the like to form a pattern of the required conductive film. This relates to the mode of transportation.

(Prior art and problems) A conductive polymer film with 89 digits of conductive film on a polymer film can be used for wiring boards, heaters, touch panel electrodes, etc.
Alternatively, it can be used as electrodes for liquid crystal displays, but generally, in order to use it for such purposes, the conductive film that is provided on the entire surface is usually left with the necessary parts and the other parts are dissolved. It is then necessary to remove or etch it into a predetermined pattern.

Recently, there has been active development of liquid crystal display elements such as liquid crystal televisions that use conductive polymer films as electrodes. However, when used as electrodes for such display elements, extremely thin electrodes are required due to the recent trend towards light, thin, and short size. It has become necessary to process conductive polymer films without causing scratches, stains, etc. during the pattern forming process.

Conventionally, as a method for etching a conductive film formed on a substrate, a mask with a predetermined pattern is first formed on the conductive layer by a screen printing method or a photoresist method, then etching is performed, and then the patterned mask is etched. A method of dissolving and removing using a stripping agent is used. This type of etching method has been widely used for Nesa glass in the past, but since the substrate is glass, there is no problem in performing etching, washing, etc. while moving it on a roller conveyor, but if the substrate is raised from glass When replacing the conductive polymer film with a molecular film, the polymer film is flexible, bends easily, and is light, making it difficult to convey smoothly and causing scratches and stains due to friction with the rollers. When I passed it through, I found that only 1q of material with insufficient conductivity could be removed, which was more than expected.

(Method for solving the problem) In order to improve the above-mentioned drawbacks, the present inventor tried a method of bonding a conductive polymer film onto a hard substrate and passing it through an etching process. It was found that the adhesive polymer film was scratched and was very time consuming, so further improvements were attempted and the present invention was developed. That is, in the present invention, a surface protective film is bonded to the opposite side of the conductive film of a polymer film having a conductive film on one side, and a process such as etching is performed in a relatively curved state to make the thickness of the bonded film 170 μm or more. This is a method of patterning a conductive film, which is characterized by:

Examples of the conductive film to be formed on the conductive polymer film to be processed in the method of the present invention include thin films of metals such as silver, copper, and aluminum, and thin films of metal oxides such as tin oxide and indium oxide. These thin films are usually formed by IM by vapor deposition etc.
be done. The vapor deposition method may be any method such as vacuum vapor deposition, RF and DC sputtering, and ion blating. Examples of the polymer film include polystyrene, polymethyl acrylate, polycarbonate, polyvinyl chloride, acetate, and polyether. Sulfone, polysulfone, polyethylene, polypropylene,
Examples include plastics such as polyamide, polytetrafluoroethylene, and polyester.

The surface protection film used in the method of the present invention may be any film that has adhesiveness on one side and has a total thickness of 170 μm or more when bonded to the conductive polymer film, but is preferably bonded to the conductive polymer film. The total thickness when combined is 170 to 250μm (for example, if the thickness of the conductive polymer film is 100μm, the thickness of the protective film is 70μm).
0 to 150 μm) A light adhesive film with a standard adhesive strength of 5 to 209/25 m width is good. For example, a film made of polyethylene film coated with an acrylic adhesive, a film made of a polyethylene film coated with a synthetic rubber adhesive,
Polypropylene film coated with synthetic rubber adhesive, polyester film coated with acrylic adhesive, polyester film coated with synthetic rubber adhesive, coextruded film of polyethylene and adhesive, polyester film coated with synthetic rubber adhesive, Examples include coextruded films with adhesives.

These surface protection films are applied to the entire surface of a polymer film having a conductive film on one side, after or before a mask is provided on the conductive film on the opposite side.

The method for providing the mask is not particularly limited, and may be any conventional method, and may be a screen printing method or a photoresist method.

In the screen marking method, a masking agent is coated onto the conductive living membrane according to the pattern using a predetermined pattern screen plate, and the predetermined pattern is formed by rapid etching.

There are two types of photoresist methods: a coating type and a resist film sticking type. In either case, a predetermined pattern can be formed by exposing and developing using a method specific to the resist, and then etching.

If the total thickness of the bonded material is less than 170 μm, it will easily bend.
If the thickness exceeds 50 μm, the conductive film will be bent when the surface protection film is peeled off, which may cause cracks in the conductive film, which is not preferable.

(Effects) In the present invention, since the surface protection film is entirely attached to the opposite side of the conductive film of the conductive polymer film, it can be done by a simple method such as passing it between two rollers.

By bonding the surface protection film to a thickness of 170 μm or more, it is relatively curved, so processing such as etching and cleaning can be performed while moving it on a low-speed conveyor without bonding it to a hard substrate. I can do it. Furthermore, the surface protection film does not damage the conductive polymer film, does not impair the transparency of the liquid crystal display element, and does not reduce visibility due to diffused reflection.

In particular, since the surface protection film is bonded over the entire surface, there is no possibility of staining with etching solution, and cleaning is simple and requires only one side, the conductive film side.

Hereinafter, the method of the present invention will be explained in detail with reference to Examples.

Example 1゜A polyethylene terephthalate film with a thickness of 100 μm was coated with indium so that the surface resistance was 3000/mm.
A thin film of tin oxide was deposited. This film was laminated with a water-soluble processed photosensitive film resist (Liston J3410, manufactured by DuPont), and then a 70 μm thick surface protection film (
Manufactured by Sunair Chemical Industry Co., Ltd., [Sanitect J PAC-3
) was laminated. After exposing the photosensitive film resist portion of this film, the unexposed portion of the photosensitive film resist was dissolved and removed with a dilute alkaline aqueous solution while moving on a roller conveyor, and after drying, the film was heated in a 25 vol.% aqueous hydrochloric acid solution (25°C). After that, the resist was removed with a 1.5% by weight aqueous sodium hydroxide solution (25°C), washed with water, and dried, and etching was completed. Moreover, when the surface protection film laminated on the surface of the polyethylene terephthalate film was peeled off, a pattern was formed on the polyethylene terephthalate film on which the indium-tin oxide thin film was deposited without any scratches or stains. The electrode formed in this manner could be used as a display electrode with excellent display quality.

Comparative Example 1 In the same manner as in Example 1, an indium-tin oxide thin film having a surface resistance of 300 Ω/hole was deposited on a polyethylene terephthalate film. The same photosensitive film resist as in Example 1 was laminated thereon and exposed. After that, while moving on a roller conveyor, the unexposed parts of the photosensitive film resist were dissolved and removed with a dilute alkaline aqueous solution, and after drying,
Etching was performed with a vol.% aqueous hydrochloric acid solution (25°C). Thereafter, the resist was removed with a 1.5% by weight aqueous sodium hydroxide solution (525°C), washed with water, and dried. As a result, although etching was achieved and a pattern was formed, the film was bent, scratched, and stained, and could not be used as a display electrode.

Claims (1)

[Claims] A method for patterning a conductive film, the method comprising: laminating a surface protective film on the opposite side of the conductive film of a polymer film having a conductive film on one side, and making the thickness of the laminated product 170 μm or more.