JP2001202826A - Transparent conductive film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transparent conductive film which is patterned without generating property deterioration, contamination and scratch. SOLUTION: A transparent conductive film is patterned by laminating a conductive film as a thin wire less than 1 mm using optical processes such as laser, without shielding or isolating surface of the transparent conductive film using a masking material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a patterned transparent conductive film used for a transparent touch panel, a transparent heater, a transparent electromagnetic wave shielding material and the like.

[0002]

2. Description of the Related Art As a method of patterning a transparent conductive film, a desired pattern mask is first formed on a conductive film surface of the transparent conductive film by a photoresist method or a screen printing method. After that, it is etched with an acid solution to remove only unnecessary portions of the conductive film,
Thereafter, a method of removing the pattern mask by dissolving or the like with a stripping agent such as an alkaline solution is performed. However, Japanese Patent Application Laid-Open No. 4-147526 states that "the transparent electrode is degraded due to the application and peeling of the resist, and the durability such as wet heat resistance is reduced." Perhaps because the transparent conductive layer deteriorates in the layer peeling process, the resistance increases and the input accuracy, or the accuracy of the detection position decreases, ''
There are problems such as durability and deterioration of the conductive film related to the product. Further, in the case of the method of etching using an acid, there are problems in terms of basic operations such as management and handling of the etching solution and treatment of the etching waste solution, and environmental problems. in addition,
Transparent conductive films such as indium tin oxide film are often formed by a sputtering method.
The properties of the conductive film tend to change depending on the type of gas, film temperature, target state, and the like, and it is difficult to set etching conditions. Further, in the case where the crystallinity of the conductive film is increased in order to improve the scratch resistance, there is also a problem that the etching is not sufficiently performed and a pattern defect occurs.

[0003]

According to the conventional patterning method, a desired pattern mask is formed on the conductive film surface of the transparent conductive film, and thereafter, etching is performed with an acid solution to remove only unnecessary portions of the conductive film. A method is used in which the pattern mask is peeled off and then the pattern mask is removed by dissolving or the like with a peeling agent such as an alkaline solution. Therefore, there is a problem that the patterned conductive film is liable to cause functional deterioration, dirt, and scratches. The problem to be solved by the present invention is to provide a transparent conductive film patterned without causing functional deterioration, dirt, and scratches of the transparent conductive film.

[0004]

Means for Solving the Problems As means for solving the above-mentioned problems, a transparent conductive film is separated into a thin line having a width of 1 mm or less without shielding and isolating the surface of the transparent conductive film with a masking material. Provided is a transparent conductive film in which a lead portion for conducting electricity is patterned. On the transparent conductive film surface side, a patterned transparent conductive film having fine irregularities is provided as an optical measure such as Newton's ring. Similarly, on the transparent conductive film surface side, a patterned transparent conductive film having an acrylic resin coating layer is provided below the conductive film as a measure to prevent the generation of oligomers from the substrate film due to heat. On the other hand, optical measures such as anti-reflection,
As a measure against surface properties such as antifouling and strength, a patterned transparent conductive film having various coating layers is provided. Further, the present invention provides a patterned transparent conductive film that is used for an analog or matrix touch panel input by a pen or a finger and that uses optical processing such as laser as a processing means.

[0005]

Embodiments of the present invention will be described below. First, various plastic films having transparency can be used as the film substrate used in the present invention. Specifically, polyethylene terephthalate (PE)
T), polyimide (PI), polyethersulfone (PES), polyetheretherketone (PEE)
K), polycarbonate (PC), polypropylene (P
P), polyamide (PA), polyacryl (PAC),
Examples include a norbornene-based thermoplastic transparent resin and the like, or a laminate thereof. On the surface on which the conductive film is provided, there may be a case where unevenness processing with an average roughness of 2 μm at the maximum is provided as a measure against Newton's ring. Similarly, an acrylic resin coating layer may be provided below the conductive film on the surface on which the conductive film is provided, as a measure to prevent the generation of oligomers from the substrate film due to heat. For touch panels, the surface of the film substrate that comes in contact with the pen or finger has transparency, scratch resistance,
In order to improve abrasion resistance, non-glare property, etc., a hard coat film or the like may be provided. The thickness of the film substrate is usually 20 to 500 μm.

[0006] Next, a method for forming a transparent conductive film is a general method for forming a transparent conductive film on a film substrate, such as a PVD method such as a sputtering method, a vacuum deposition method, an ion plating method, or a CVD method. Method, coating method, printing method and the like. The material for forming the transparent conductive film is not particularly limited. For example, indium-tin composite oxide (ITO), tin oxide, copper, aluminum, nickel,
Chromium and the like may be used, and different forming materials may be formed by being stacked. Before forming the transparent conductive film, an undercoat layer for improving transparency, adhesion, and the like may be provided.

Next, regarding the patterning, conventionally, the transparent conductive film is peeled off in a plane as shown in FIG.
In the portion where 11a, 11b and 11c in FIG.
2 is a peeled portion. However, in view of the flow of electricity, it is not necessary to peel off the sheet. That is, it is only necessary to cut into thin lines so that only the conductive film surface of the transparent conductive film surface is scribed as shown in the examples of FIGS. 1A and 1B so that electricity flows as designed. FIG. 1 (a) shows the outer shape cut, and the peel length is the shortest. FIG. 1 (b) shows an example of continuous cutting when relatively small identical patterns are continuously arranged. Therefore, in the process, if the transparent conductive film is fixed, irradiated with laser light, and the transparent conductive film or the laser light is moved, the conductive film can be peeled in a thin line shape. Once the conditions are determined, it is a very simplified process.

[0008] Conventionally, a conductive film surface of a transparent conductive film is formed with a desired pattern mask, and then etched with an acid solution to peel off only unnecessary portions of the conductive film. It is very different from a method of repeating a number of steps of removing the pattern mask by dissolving or the like with an agent. Of course, it is possible to peel the surface by overlapping thin wires, but it is not efficient in the case of a large area.

As a device, a table and a laser device which hold the film and can move in two dimensions are required. It is desirable that the table be sucked to eliminate the undulation of the film. As the irradiation conditions of the laser device, the distance to the table, the output, and the method of continuous irradiation or pulse irradiation are set. In the case of pulse irradiation, the pulse frequency is also set. The table sets the moving speed, moving distance, and moving conditions of the moving direction. All the setting conditions may be input to the controller and automated. If the conditions are set, the transparent conductive film positioned at the film edge or the reference hole is fixed to the table, and laser irradiation is performed while moving the table to perform fine line patterning. Of course, the table may be fixed and the laser beam side may be movable, and irradiation may be performed. If a winding-up and winding-up device is installed on the table, processing of a roll film is also possible. The film patterned by the laser processing is suitable for a heater or a touch panel, since no residue of the mask material and resistance deterioration occur in the production process. As a post-process, there is a case in which a wiring circuit is printed with a conductive ink or an insulating printing is performed on the wiring circuit.

[0010]

EXAMPLES (Example 1) As a laser device, there are a YAG laser, a carbon dioxide laser, and the like, but a YAG laser that causes less damage to a film due to heat or the like was selected. YAG used
The oscillation wavelength of the laser is near infrared light of 1.064 μm, and the beam diameter where the beam is most focused is 0.45 mm.
Are combined. The laser pulse light having a large peak value is irradiated by the Q switch, and the film sucked and fixed on the table moves at the same pitch in synchronization with the laser pulse. That is, if a signal of one pulse is input, irradiation is performed on a circular surface having a diameter of 0.45 mm, and
Move the pitch. The amount of one pitch movement is 0.45 mm or less and is determined so that the circles overlap each other as shown in FIG. Therefore, the irradiation width is a repetition of a wide portion and a narrow portion, and the wide portion is the diameter of the circle, and the narrow portion is the distance between the intersections of the circles.

The film substrate of Example 1 has a thickness of 1
An 88 μm PET film was used. On that film,
An ITO film having a sheet resistance of 300 (Ω / □) was formed by a sputtering method. The patterning processing conditions were set to a laser oscillation output of 23 W, a laser oscillation pulse frequency of 3 KHz, and a table moving speed of 1026 mm / S. One pitch movement amount per one pulse is calculated from the table movement speed and the laser oscillation pulse frequency, and is 0.342 mm.
In this case, the portion where the irradiation width is wide is 0.45 mm,
The distance between the intersections of the circles, which are narrow places, is approximately 0.292 mm. Table moving distance is straight line 30c
When the thin line patterning was performed as m, the conductive surface was continuously peeled in a wide irradiation range from 0.45 mm to 0.41 mm in a wide irradiation area and in a narrow irradiation range from 0.32 mm to 0.28 mm in a narrow irradiation width. I was In terms of appearance, there was no swelling or dent exceeding 1 μm due to melting of the underlying film, and no microcracks were generated on the conductive surface. Electrically, the insulation resistance when a direct current of 25 volts was applied was 100 MΩ or more. Temperature 60 ° C, Humidity 9
Even after 120 hours at 0%, the appearance and the insulation resistance were good without any change.

(Example 2) As a film substrate, an arton film made of JSR Co., Ltd. ("ARTON" is a registered trademark of the company) made of a norbornene-based thermoplastic transparent resin having a thickness of 188 μm was used. An ITO film having a sheet resistance of 300 (Ω / □) was formed on the film by a sputtering method. All conditions of the apparatus and laser oscillation output, laser oscillation pulse frequency, table moving speed, and table moving distance are described in Example 1.
And the same. The results were as good as in Example 1.

(Example 3) As a film substrate, PET having a thickness of 188 μm and an average roughness of 2 μm at the maximum was used.
A film was used. An ITO film having a sheet resistance of 300 (Ω / □) was formed on the uneven surface of the film by a sputtering method. The conditions of the apparatus and the laser oscillation pulse frequency, table moving speed, and table moving distance were the same as those in Example 1, but the laser oscillation output was 34 W. The results were as good as in Example 1.

(Comparative Example 1) With the sputtered film of Example 3, all the conditions of the apparatus, laser oscillation output, laser oscillation pulse frequency, table moving speed, and table moving distance were the same as in Example 1. The result was peeled in a thin line shape, but completely peeled off was 0.2 ~
At a width of 0.3 mm, the conductive film was partially left at the edge.

[0015]

The present invention is embodied in the form described above, and has the following effects. That is, in the present invention, when patterning a transparent conductive film made of an indium tin oxide film or the like, a desired pattern mask is formed on the transparent conductive film, followed by etching, and thereafter, the pattern mask is removed with a release agent. Since there is no conventional processing, the process is greatly reduced. And functionally, the deterioration and over-etching of the transparent conductive film,
In the case of a touch panel, shortage of etching does not occur, and input accuracy and detection accuracy are excellent. Further, the yield is improved without any trouble due to the residue, dirt and scratches caused by the mask material. Naturally, equipment and maintenance for etching, stripping, cleaning, and water treatment are not required, and the environment does not handle acid or alkali chemicals. In addition, since a mask plate is not required, not only the cost and production time of the plate, but also the mounting setup time are not required, and the effect is extremely large.

[Brief description of the drawings]

FIGS. 1A and 1B are explanatory diagrams showing an example of fine line patterning.

FIG. 2 is an explanatory view showing the shape of laser irradiation for fine line patterning.

FIG. 3 is an explanatory view showing an example of conventional patterning.

[Explanation of symbols]

10: transparent conductive film 11: conductive film portion of transparent conductive film 11a: conductive film portion of transparent conductive film (current-carrying portion) 11b, 11c: conductive film portion of transparent conductive film (lead portion) 12: transparent conductive film 20: The part where the circular surface moves and the laser is irradiated every pulse

Claims (6)

[Claims] A transparent conductive film is provided on at least one surface, and the conductive film is peeled into a thin line having a width of 1 mm or less without shielding and isolating the transparent conductive film surface with a masking material. Transparent conductive film with a patterned lead. 2. The transparent conductive film according to claim 1, wherein the transparent conductive film surface has fine irregularities. 3. The transparent conductive film surface has an acrylic resin coating layer under the conductive film.
3. The transparent conductive film according to item 1. 4. The transparent conductive film according to claim 1, wherein a coating layer is provided on a surface having no transparent conductive film. 5. The transparent conductive film according to claim 1, which is used for a transparent touch panel. 6. The transparent conductive film according to claim 1, wherein the transparent conductive film is formed by optical processing such as a laser.