KR20020027938A - Touch panel - Google Patents

Abstract

PURPOSE: A touch panel is provided to reduce the production cost and to enhance the productivity by enabling the parts wanted to exchange to easily exchange the defect part. CONSTITUTION: The touch panel comprises an upper substrate(11) equipped with an upper transparent conductive film(12), a lower substrate(15) equipped with a lower transparent conductive film(14), a plurality of dot spacers(16) formed between the upper and lower transparent film in order to prevent the contact between the upper and lower transparent film without outer pressure, and an adhesive layer adhering the upper and lower transparent film. The adhesive layer adhering the upper and lower transparent film uses a formed both-faces adhesive tape. Both faces of supporter are coated with the adhesive agent and the under coating connecting the supporter with the adhesives is inserted between the supporter and the adhesives. The materials of supporter are polyurethane and polyethylene. The formed both-faces adhesive tape has a thickness of 50-150 micrometers, the diameter of foamed particle is 20-70micrometers and the materials of foam is expanded by 2 to 5times at 150 deg.C.

Description

Touch panel {Touch panel}

The present invention relates to a touch panel, and more particularly, to a touch panel employing a double-sided adhesive or double-sided tape in which foamed resin is incorporated.

The display device is a device for displaying an image, and research and development of the display device has been continuously progressed since the appearance of the cathode ray tube (CRT). In particular, research / development has been actively developed in the field of flat panel display devices, and as a result, various flat panel display devices have shown lines. In other words, liquid crystal display (LCD) using optical characteristics (transmitting or blocking light according to changes in voltage and temperature) and liquid crystal display (PDP) using gas discharge due to a strong electric field. Panel, VFD (Vacuum Fluorescent Display), which emits letters and symbols by colliding electrons emitted from the cathode in the vacuum vessel to the fluorescent surface, and optoelectrons in the light emitting layer accelerated by high field. The ELD (Electroluminescent Display) using light emitted when returning to the level is the main dominant of such a flat panel display device. In addition, there are flat panel display devices using a change in capacitance or a change in voltage caused by a contact object.

However, in order to use information easily by using such an image display device, there are a touch panel and a digitizer as input devices. According to such an input device, a button displayed on a display by an input means, ie, a hand or a pen, is used. The contact information may be connected in a contact or non-contact manner to easily use the information of the electrically connected image display device.

In addition, the touch panel used with the image display device is applied to a pen computer or a personal information terminal, and the use thereof is being increased, and an analog resistive type, a digital resistive type, and an infra red Various types of touch panels, such as an infrared type, a saw type, and a capacitive type, are used.

1 is a cross-sectional view of a conventional touch panel. Referring to the drawings, the touch panel includes an upper substrate 11 and a lower substrate 15 that face each other, an adhesive layer 13 and a dot space 16.

The lower substrate 15 and the upper substrate 11 are electrically insulated from each other, a lower transparent conductive film 14 is formed on the lower substrate 15, and an upper transparent conductive film is formed on the bottom surface of the upper substrate. In addition, the transparent conductive film mainly uses an indium tin oxide (ITO) film.

On the lower transparent conductive film 14, dot spaces 16 are uniformly formed in the same shape at predetermined intervals, and the upper substrate 11 and the lower substrate 15 are adhered to each other by an adhesive layer 13 do. Here, the adhesive layer 13 is composed of a double-sided tape or double-sided adhesive.

Looking at the operation of the touch panel according to such a configuration as follows. When a point of the upper substrate 11, which is a flexible film material, is pressed by an input means such as a pen or a hand, one point of the transparent conductive films 12 and 14 formed on the upper substrate 11 and the lower substrate 15 is in contact. Will be energized. At this time, when the voltage value changed according to each resistance value is read out and the control unit converts the digital value according to the change in the potential difference to find the position coordinate, the contact position is measured.

However, in the conventional touch panel, since the upper substrate 11 and the lower substrate 15 are bonded to each other using a double-sided tape or a double-sided adhesive, the adhesive force of the double-sided tape or the double-sided adhesive is increased while undergoing heat treatment or the like in the manufacturing process of the touch panel. It is difficult to peel it off because it is strengthened by heat. Therefore, if the upper substrate and the lower substrate are bonded to each other, the ITO (indium tin oxide) film used as a transparent conductive film is damaged by scratching, stamping, or the like during the touch panel manufacturing process. If so, it should be disposed of as is. In addition, if the ITO film of the touch panel is damaged while the product is shipped and the user is using it, the damaged product is discarded and replaced with a new product.

The present invention has been devised to improve such a problem, and when a defect occurs among materials constituting the touch panel, a touch panel capable of repairing can be implemented so as to smoothly exchange the material to be replaced, thereby reducing costs and It is for achieving productivity improvement.

1 is a cross-sectional view of a conventional touch panel.

Figure 2 is a cross-sectional view of a touch panel according to an embodiment of the present invention, a cross-sectional view of a touch panel using a foamed double-sided adhesive tape.

Figure 3 is a cross-sectional view of a touch panel according to another embodiment of the present invention, a cross-sectional view of a touch panel using a double-sided adhesive agent mixed with foamed resin.

4 is a cross-sectional view of the foam double-sided adhesive tape.

<Description of Symbols for Major Parts of Drawings>

11. Upper board 15. Lower board

12. Upper transparent conductive film 14. Lower transparent conductive film

13. Adhesive layer 16. Dot spacer

20. Foam double sided adhesive tape

30. Double sided adhesive with foamed resin

41.Support 42.Conductor

43. Adhesive

In order to achieve the above object, the present invention provides an upper substrate on which the upper transparent conductive film is formed; and a lower substrate on which a lower transparent conductive film is formed; and a predetermined pressing force is formed between the upper transparent conductive film and the lower transparent conductive film. Otherwise, a plurality of dot spacers in which contact between upper and lower transparent conductive films is prevented; And an adhesive layer for adhering the upper substrate and the lower substrate to each other, wherein the touch panel has a structure in which the adhesive layer is detachable.

Hereinafter, an embodiment of a touch panel according to the present invention will be described in detail with reference to the accompanying drawings.

2 illustrates a cross-sectional view of an embodiment of a touch panel according to the present invention. Referring to FIG. 2, a foamed double-sided adhesive tape 20 (FIG. 4) is used as an adhesive layer for bonding the upper substrate 11 and the lower substrate 15 to each other.

Looking at the structure of the foam double-sided adhesive tape 20 as shown in FIG. Referring to the drawings, the double-sided adhesive tape has an adhesive 43 distributed on both sides of the support 41, and a conductor 42 connecting the support 41 and the adhesive 43 has the support 41 and the adhesive. Sandwiched between 43.

Examples of the material of the support 41 include polyurethane, polyethylene, and the like. When heat is applied to the material, bubbles in the material are foamed to significantly lower the adhesive force.

In addition, the thickness of the foamed double-sided tape (20, Fig. 4) is preferably 50 ~ 150 ㎛, the diameter of the foam particles 20 ~ 70 ㎛ is preferred, the material that foams 2 to 5 times when subjected to 150 ℃ heat is preferred.

Figure 3 shows a cross-sectional view of another embodiment of a touch panel according to the present invention. Referring to FIG. 3, a double-sided adhesive agent 30 containing a foamed resin is used as an adhesive layer 13 for adhering the upper substrate 11 and the lower substrate 15.

At this time, the diameter of the foam particles is preferably 20 ~ 70 ㎛ and preferably a material that foams 2 to 5 times when subjected to heat of 150 ℃.

According to the touch panel according to the present invention, when a predetermined heat is applied to the adhesive layer, foaming is formed in the adhesive layer so that the adhesive layer can be easily peeled off, thereby selectively repairing a defect generated during the manufacturing process of the touch panel, thereby reducing the cost. The cost savings can be improved and productivity can be increased, and repairs can be made selectively, even if the defects may be caused by improper use by the user, rather than a total replacement. In addition, when the end-of-life of the touch panel is used up, it is possible to effectively cope with the separation of used materials.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (3)

An upper substrate having an upper transparent conductive film formed on one surface thereof; A lower substrate provided to face the upper substrate and having a patterned lower transparent conductive film formed on one surface thereof; A plurality of dot spacers interposed between the upper substrate and the lower substrate to maintain a gap therebetween; And Touch panel, characterized in that the adhesive layer for bonding the upper substrate and the lower substrate is made of a detachable material The method of claim 1, A touch panel comprising a foamed double-sided adhesive tape as the adhesive layer. The method of claim 1, The adhesive layer is a touch panel, characterized in that the foam mixed with a double-sided adhesive agent.