JPH04314121A - Touch panel - Google Patents

Abstract

PURPOSE:To prevent imperfect connection between an electrode and an output circuit and a defect that the output circuit is peeled off from a polymer film. CONSTITUTION:A first electrode 5 such as ITO is installed on the polymer film 2, and a first output circuit 6 to be c1onnected to this first electrode 5 and a second output circuit 7 insulated from the first electrode 5 are installed by applying Ag paste, etc., and these are made into a first insulated base board 1. Then, a conductive adhesive layer 14 is laminated at the part of the polymer film 2 at the surface of the second output circuit 7 and its periphery, and in addition, it comes into contact with a second electrode 11 so as to connect both electrically, and a touch panel 10 is formed. Since the conductive adhesive layer is laminated not only at the surface of the second output circuitk but up to the part of the polymer film at its periphery, the defect that the conductive adhesive layer is peedled off from the second output circuit and the imperfect connection is caused, or the second output circuit is peeled off from the polymer film can be prevented even if stress is applied to the conductive adhesive layer since the internal pressure is increased.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a touch panel.

0002

2. Description of the Related Art Conventionally, a touch panel has been installed on the surface of a display such as a CRT display or a liquid crystal display and used as an information input device or a coordinate indicating device.

For example, as shown in FIG. 3, this touch panel has a structure in which an insulating substrate 20 in which electrodes are formed on a glass plate, an acrylic plate, etc., and an insulating substrate 21 in which electrodes are formed in a flexible polymer film are laminated. ing. In order to connect the electrode to an external circuit, a lead-out circuit made of Ag paste or the like is provided and connected to the electrode. However, if a lead-out circuit is provided on the glass plate or the like in the former case, it will be costly to connect it to an external circuit, so usually, the lead-out circuit 23 for the electrode 22 formed on the insulating substrate 20 in the former case is
They are also provided on the latter insulating substrate 21 made of a polymer film. Then, the surface of the electrode 22 and the extraction circuit 2
A conductive adhesive 24 is laminated only on the surfaces of 3 and 3 to electrically connect them to each other.

0004

[Problems to be Solved by the Invention] However, when a touch panel is exposed to a high-temperature atmosphere, the internal pressure increases and the touch panel swells, and when exposed to a high-humidity atmosphere, the polymer film sag and swell. Therefore, stress is applied to the portion of the conductive adhesive layer, resulting in a disadvantage that poor connection between the electrode and the extraction circuit is likely to occur.

[0005] Furthermore, the Ag paste used to form the lead-out circuit has relatively low adhesion to the polymer film, and therefore, if stress is applied to the conductive adhesive layer, the lead-out circuit will separate from the polymer film. It also has the disadvantage of peeling.

SUMMARY OF THE INVENTION An object of the present invention is to improve the above-mentioned drawbacks and to provide a touch panel that can prevent poor connection between electrodes and take-out circuits and failures such as peeling of the take-out circuits from the polymer film.

[0007]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a first electrode on a polymer film, a first extraction circuit connected to the first electrode, and a first electrode connected to the first electrode. A second insulating substrate is provided with a second insulating circuit insulated with a second electrode, and the first insulating substrate is laminated on a second insulating substrate provided with a second electrode, and the second insulating circuit is insulated with the second electrode. The present invention provides a touch panel connected via an adhesive layer, characterized in that a conductive adhesive layer is provided that is laminated up to a portion of the polymer film around the second take-out circuit.

[0008]

[Function] The conductive adhesive layer is not only laminated only on the second take-out circuit and connected to the second electrode, but also on the part of the polymer film around the second take-out circuit.
At this location, the polymer film can be firmly bonded to the second insulating substrate. Therefore, even if the internal pressure increases or the polymer film becomes sagging and stress is applied to the conductive adhesive layer, there may be a poor connection between the second take-out circuit and the second electrode, or if the second take-out circuit is made of polymer film. It can prevent it from peeling off from the film.

[0009]

EXAMPLES The present invention will be explained below based on examples. FIG. 1 shows a plan view of the first insulating substrate 1. As shown in FIG. Reference numeral 2 denotes a flexible polymer film such as polyester, which has a rectangular shape and has protruding first and second tail parts 3 and 4 on its long and short sides, respectively. 5 is this polymer film 2
The first electrode is made of ITO or the like and is formed in a rectangular shape with the long side aligned with the short side of the polymer film 2, and a plurality of strips are arranged in parallel with each other. 6 is a first electrode provided by printing Ag paste or the like from the first tail portion 3 to the first electrode 5.
This is the extraction circuit. 7 passes through the second tail portion 4 and the first
This is a second extraction circuit provided up to the vicinity of the electrode 5. The end of the second extraction circuit 7 closer to the first electrode 5 has a wider width and forms a second electrode head portion 8 .

FIG. 2 shows a first insulating substrate 1 and a second insulating substrate 9.
The touch panel 10 is shown laminated on the top of the screen. The second insulating substrate 9 is a glass plate, an acrylic plate, etc., on which a plurality of second electrodes 11 are provided, and dot-shaped spacers 12 are provided at appropriate intervals. The second electrode 11 has a rectangular shape and is provided in a direction perpendicular to the first electrode 5 provided on the first insulating substrate 1 . Reference numeral 13 denotes a spacer made of double-sided tape or the like, and is arranged between the ends of the first insulating substrate 1 and the second insulating substrate 9. Reference numeral 14 denotes an anisotropic conductive adhesive layer, which is laminated between the second electrode 11 and the second take-out circuit 7, and in particular, is laminated to the surface of the polymer film 2 around the second take-out circuit 7. It is set up as follows.

Next, the manufacturing method of the above embodiment will be described. First, a transparent conductive film is laminated on the polymer film 2 by sputtering or vacuum deposition of ITO or the like, and the first electrode 5 is formed by etching. Next, the first extraction circuit 6
And the second extraction circuit 7 is formed by printing Ag paste or the like. After forming each circuit 6 and 7, the polymer film 2 is cut into a predetermined shape.

[0012] Further, a transparent conductive film is laminated by sputtering ITO or the like on a glass plate or the like that has been previously formed into a predetermined shape, and then etched to form the second electrode 11. After forming the second electrode 11, dot-shaped spacers 12 are printed and formed.

Further, an anisotropic conductive adhesive layer 14 is laminated and temporarily bonded to the second electrode head portion 8 of the second extraction circuit 7 and its surroundings, and the first insulating substrate 1 and the second insulating substrate 9 are bonded together. Attach the ends to each other using double-sided tape, etc. Then, the thermal head 13 is pressed from the first insulating substrate 1 side of the touch panel 10 to hot press the anisotropically conductive adhesive layer 14 .

Next, a wet/dry cycle test was conducted for the example and the conventional example, and changes therein were measured. The manufacturing conditions for Examples etc. are as follows.

Example: Polyester film 20×30cm thick polyester film 175 μm thick
m (excluding the first tail part and the second tail part) in a rectangular shape. A transparent conductive film made of ITO electrodes with a thickness of 400 A is applied and printed with Ag ink for the first and second extraction circuits to a thickness of 10 μm. A 4 mm wide Anisolm (trade name, manufactured by Hitachi Chemical Co., Ltd.) is used as an anisotropic conductive adhesive for thermocompression bonding, and is laminated on the second electrode head portion and its periphery. And from the Anisorum side 4
Apply a heat head of mm x 17 cm and heat the anisolum to temperature 1.
Temporarily press-bond by heat pressing at 00°C for 5 seconds at a pressure of 4 kg/cm2. After this temporary pressure bonding, the separator is peeled off from the Anisolm, and from the polymer film side, the Anisolm is heated to 150° C. and hot pressed at 20 kg/cm 2 for 20 seconds to perform the main bonding.

Conventional example: In the example, a 3 mm wide anisolm was used as the anisotropic conductive adhesive, and this was laminated only on the second electrode head portion, and was not laminated around it.

In the wet-dry cycle test, the touch panel is left in an atmosphere at a temperature of 65° C. and humidity of 95% RH for 1 hour, and then dried at a temperature of 65° C. for 1 hour, which is repeated 100 times. Furthermore, the number of samples used in the test was five for both the example and the conventional example.

As a result of the test, in the conventional example, the second electrode head part was lifted from the polymer film, but in the example, there was no change.

Further, when a probe was brought into contact with the second electrode and the electrode was connected to the second extraction circuit, the electrical resistance therebetween was measured, and the results shown in Table 1 were obtained.

[0020]

As is clear from Table 1, the resistance value does not change according to the example, but increases by 50 times according to the conventional example.

[0022]

As described above, according to the present invention, since the conductive adhesive layer is laminated not only on the edge of the second lead-out circuit but also on the portion of the polymer film around it, the conductive adhesive layer A touch panel can be obtained that can prevent connection failures at the agent layer portion and failures in which the second extraction circuit peels off from the polymer film.

[Brief explanation of drawings]

FIG. 1 shows a plan view of a first insulating substrate used in an example of the present invention.

FIG. 2 shows a cross-sectional view of an embodiment of the invention.

FIG. 3 shows a cross-sectional view of a conventional touch panel.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1...First insulating substrate, 2...Polymer film, 5...
First electrode, 6... First extraction circuit, 7... Second extraction circuit, 8... Second electrode head portion, 9... Second insulating substrate, 10... Touch panel, 11... Second electrode, 14... Anisotropic conductive adhesive agent layer.

Claims (1)

[Claims] 1. A first insulating substrate including a first electrode provided on a polymer film, a first extraction circuit connected to the first electrode, and a second extraction circuit insulated from the first electrode; In a touch panel in which this first insulating substrate is laminated on a second insulating substrate provided with a second electrode, and the second take-out circuit is connected to the second electrode via a conductive adhesive layer, the area around the second take-out circuit is A touch panel characterized by providing a conductive adhesive layer laminated to a portion of a polymer film.