JP2012128675A - Touch panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly durable and reliable touch panel.SOLUTION: A touch panel includes: an upper electrode substrate having an upper conductive film; a lower electrode substrate having a lower conductive film; and a flexible substrate having an electrode terminal connected to an electrode terminal provided on the upper electrode substrate and an electrode terminal connected to an electrode terminal provided on the lower electrode substrate. The electrode terminal provided on the upper electrode substrate and the electrode terminal provided on the flexible substrate are electrically connected with each other by thermocompression bonding. The electrode terminal provided on the lower electrode substrate and the electrode terminal provided on the flexible substrate are electrically connected with each other by thermocompression bonding.

Description

  The present invention relates to a touch panel.

  The touch panel is an input device that can directly input to the display, and is often installed and used on the front surface of the display. Touch panels are widely used in various applications because they can be directly input based on information visually captured by a display.

  As such a touch panel, a resistance film method is widely known. The resistive film type touch panel is installed so that each transparent conductive film is opposed to each other in the upper electrode substrate and the lower electrode substrate on which the transparent conductive film is formed, and each of the upper electrode substrates is applied with a force. The transparent conductive films are in contact with each other, and the position where the force is applied can be detected.

  Resistive touch panels can be broadly classified into four-wire, five-wire, and diode. In the 4-wire system, an X-axis electrode is provided on one of the upper electrode substrate and the lower electrode substrate, and a Y-axis electrode is provided on the other (for example, Patent Document 1). In the 5-wire system, both the X-axis electrode and the Y-axis electrode are provided on the lower electrode substrate, and the upper electrode substrate functions as a probe for detecting a voltage (for example, Patent Documents). 2). The diode type has a structure in which a diode is provided on the lower electrode substrate, and is provided with two electrodes for applying a voltage and four electrodes for monitoring a potential. In addition to the electrodes provided on the upper electrode substrate that functions as a probe for detecting the presence of seven electrodes, it is also called a seven-wire type (for example, Patent Document 3).

  A 7-wire touch panel will be described with reference to FIGS. The 7-wire touch panel has an upper electrode substrate 210 formed in a substantially rectangular shape by a transparent film or the like, a lower electrode substrate 220 formed in a substantially rectangular shape by a glass substrate or the like, and a flexible substrate 240.

  A transparent conductive film is formed on the surface of the upper electrode substrate 210, and a film electrode 211 for connecting to the flexible substrate 240 via the lower electrode substrate 220 is provided.

  A transparent conductive film is formed on the surface of the lower electrode substrate 220. A connection terminal 231 that is electrically connected to the film electrode 211 in the upper electrode substrate 210 is provided, and the connection terminal 231 is electrically connected to the electrode terminal 233 via a wiring 232. In addition, six electrode terminals 234, 235, 236, 237, 238, and 239 that are electrically connected to wiring (not shown) provided around the lower electrode substrate 220 are provided.

  The flexible substrate 240 is provided with seven wires, and ends of these wires are connected to electrode terminals 233, 234, 235, 236, 237, 238, and 239 provided on the lower electrode substrate 220. Seven electrode terminals 243, 244, 245, 246, 247, 248, and 249 are formed.

  As shown in FIGS. 4 and 5, the upper electrode substrate 210 and the lower electrode substrate 220 are joined to each other by a double-sided tape 251, and the film electrode 211 on the upper electrode substrate 210 and the lower electrode substrate 220 on the lower electrode substrate 220 are joined. The connection terminal 231 is connected via a conductive adhesive 252. The electrode terminals 243, 244, 245, 246, 247, 248, and 249 on the flexible substrate 240 are heat-treated with the electrode terminals 233, 234, 235, 236, 237, 238, and 239 provided on the corresponding lower electrode substrate 220. Connected by crimping.

  More specifically, as shown in FIG. 5, a transparent conductive film 212 is provided on the surface of the upper electrode substrate 210, and a film electrode 211 is provided on the transparent conductive film 212. FIG. 5 is a cross-sectional view taken along the alternate long and short dash line 4A-4B in FIG.

  A transparent conductive film 221 made of ITO (Indium Tin Oxide) or the like is formed on the surface of the lower electrode substrate 220, and an insulating film 222 is formed on the transparent conductive film 221. The insulating film 222 is formed of a thermosetting or ultraviolet curing acrylic resin. On the insulating film 222, connection terminals 231, wirings 232, and electrode terminals 233, 234, 235, 236, 237, 238, and 239 are formed. The connection terminal 231, the wiring 232, and the electrode terminals 233, 234, 235, 236, 237, 238, and 239 are formed by performing screen printing using a silver paste and then heating and drying. Note that an insulating film 223 is formed on the wiring 232 and the like.

  The flexible substrate 240 is provided with seven copper wirings as wirings, and electrode terminals 243, 244, 245, 246, 247, 248, 249 are formed by exposing a part of the copper wiring. ing.

  As described above, the electrode terminals 233, 234, 235, 236, 237, 238, and 239 in the lower electrode substrate 220 correspond to the electrode terminals 243, 244, 245, 246, 247, 248, and 249 in the flexible substrate 240, respectively. The electrode terminals to be connected are connected. For example, in the case shown in FIG. 5, the electrode terminal 233 provided on the lower electrode substrate 220 is connected to the electrode terminal 243 provided on the flexible substrate 240, and the electrode terminal 234 provided on the lower electrode substrate 220 is Each electrode is connected to an electrode terminal 244 provided on the flexible substrate 240, and the electrode terminal 239 provided on the lower electrode substrate 220 is connected to an electrode terminal 249 provided on the flexible substrate 240. The terminals are connected.

JP 2004-272722 A JP 2008-293129 A JP 2005-196280 A

  By the way, in the touch panel having such a structure, when the touch panel is driven, a voltage may be applied between the transparent conductive film 212 in the upper electrode substrate 210 and the transparent conductive film 221 in the lower electrode substrate 220. In this case, since the transparent conductive film 212 in the upper electrode substrate 210 is connected to the connection terminal 231, the wiring 232, and the electrode terminal 233 in the lower electrode substrate 220 via the conductive adhesive 252, the connection terminal in the lower electrode substrate 220. 231, the wiring 232, and the electrode terminal 233 are equal to the potential of the transparent conductive film 212 in the upper electrode substrate 210. Accordingly, a potential difference is generated between the transparent conductive film 221 formed on the surface of the lower electrode substrate 220 via the insulating film 222 and the connection terminal 231, the wiring 232, and the electrode terminal 233, and an electric field concentrates in the insulating film 222.

  Since the insulating film 222 is formed thin, an electric field concentrates between the transparent conductive film 221 and the connection terminal 231, the wiring 232, and the electrode terminal 233, thereby forming the connection terminal 231, the wiring 232, and the electrode terminal 233. The silver ions that have migrated in the insulating film 222 may reach the transparent conductive film 221 in the lower electrode substrate 220 in some cases. In this case, an insulation failure occurs in the insulating film 222 in the region where the silver ions have migrated. Such an insulation failure is particularly prominent in an environment at high temperature and high humidity, and has been a factor of reducing the durability of the touch panel.

  The present invention has been made in view of the above, and an object of the present invention is to provide a touch panel having a structure in which migration of metal ions such as silver ions hardly occurs and has improved durability and reliability. To do.

  The present invention provides an upper electrode substrate having an upper conductive film, a lower electrode substrate having a lower conductive film, an electrode terminal connected to an electrode terminal provided on the upper electrode substrate, and the lower electrode substrate. A flexible substrate having an electrode terminal connected to the electrode terminal, and the electrode terminal provided on the upper electrode substrate and the electrode terminal provided on the flexible substrate are electrically connected by thermocompression bonding The electrode terminal provided on the lower electrode substrate and the electrode terminal provided on the flexible substrate are electrically connected by thermocompression bonding.

  Further, the present invention is characterized in that the upper electrode substrate is made of a transparent resin material.

  The present invention is characterized in that, in the flexible substrate, a cut portion is provided between an electrode terminal connected to the upper electrode substrate and an electrode terminal connected to the lower electrode substrate. .

  Further, the present invention is characterized in that the thermocompression bonding between the electrode terminal provided on the upper electrode substrate and the electrode terminal on the flexible substrate is performed at a temperature of 150 ° C. or lower.

  In the present invention, the electrode terminal provided on the flexible substrate connected to the electrode terminal provided on the upper electrode substrate has a plurality of electrode terminals with respect to one electrode terminal provided on the upper electrode substrate. Is provided.

  According to the present invention, the flexible substrate has a metal film formed on both surfaces of the insulating film, and the metal film formed on both surfaces of the insulating film is a through hole provided in the insulating film. It is electrically connected via the.

  Further, the invention is characterized in that the number of wirings provided on the flexible substrate is five or seven.

  ADVANTAGE OF THE INVENTION According to this invention, it is a structure which is hard to generate | occur | produce migration of metal ions, such as silver ion, Comprising: The touch panel of the structure which improved durability and reliability can be provided.

Structure of the upper electrode substrate of a conventional 7-wire touch panel Structural diagram of lower electrode substrate of conventional 7-wire touch panel Structural diagram of a flexible substrate for a conventional 7-wire touch panel Structure of a conventional 7-wire touch panel Sectional view of a conventional 7-wire touch panel Structural diagram of upper electrode substrate of touch panel in first embodiment Structural diagram of lower electrode substrate of touch panel in first embodiment Structural drawing of the double-sided tape of the touch panel in the first embodiment Structural diagram of flexible substrate of touch panel in first embodiment Structural diagram of the touch panel in the first embodiment Sectional drawing of the touchscreen in 1st Embodiment Illustration of a conventional touch panel Explanatory drawing of the touch panel in 1st Embodiment Structural diagram of flexible substrate of touch panel in second embodiment Sectional drawing of the flexible substrate of the touchscreen in 2nd Embodiment

  The form for implementing this invention is demonstrated below. In addition, about the same member etc., the same code | symbol is attached | subjected and description is abbreviate | omitted.

[First Embodiment]
(Touch panel)
The touch panel in the first embodiment will be described with reference to FIGS. The touch panel in the present embodiment is a 7-wire touch panel, and includes an upper electrode substrate 10 formed of a transparent film or the like, a lower electrode substrate 20 formed of a glass substrate or the like, and a flexible substrate 40. ing.

  A transparent conductive film is formed on the surface of the upper electrode substrate 10, and a film electrode terminal 11 and a film electrode 12 for connecting to the flexible substrate 40 via the lower electrode substrate 20 are provided. The upper electrode substrate 10 is formed in a film shape, and the material for forming the upper electrode substrate 10 is a transparent resin material such as polyethylene terephthalate, polycarbonate, heat-resistant polycarbonate, polyethylene naphthalate, and polyethersulfone. , Cyclic polyolefin, norbornene resin, polyarylate, polypropylene, heat-resistant nylon and the like are used.

  A transparent conductive film is formed on the surface of the lower electrode substrate 20, and six electrode terminals 31, 32, 33, 34, 35 connected to a wiring (not shown) provided around the lower electrode substrate 20, 36 is provided. As the material for forming the lower electrode substrate 20, glass and plastic are used. As the plastic, polycarbonate, heat-resistant polycarbonate, polyacrylate, polymethacrylate, cyclic polyolefin, norbornene resin, polyarylate, polypropylene Heat resistant nylon or the like is used. A dot spacer (not shown) is formed on one surface of the upper electrode substrate 10 or the lower electrode substrate 20.

  The upper electrode substrate 10 and the lower electrode substrate 20 are bonded to each other with a double-sided tape 51 shown in FIG. 8 with the surfaces on which the transparent conductive film is formed facing each other. The double-sided tape 51 has a shape in which a central portion is cut out, and an adhesive resin, a printing paste, or the like may be used in addition to the double-sided tape 51.

  The flexible substrate 40 has seven wirings, and electrode terminals 41, 42, 43, 44 for connecting to electrode terminals 31, 32, 33, 34, 35, 36 provided on the lower electrode substrate 20. , 45 and 46 and two electrode terminals 47 and 48 for connection to the film electrode terminal 11 provided on the upper electrode substrate 10 are formed. Since the electrode terminals 41, 42, 43, 44, 45, 46 in the flexible substrate 40 are connected to the electrode terminals 31, 32, 33, 34, 35, 36 provided on the lower electrode substrate 20, On the side. Moreover, since the electrode terminals 47 and 48 in the flexible substrate 40 are connected to the film electrode terminal 11 in the upper electrode substrate 10, they are provided on the surface side in FIG. 9.

  Further, the flexible substrate 40 is provided with a notch 49 between the electrode terminals 41, 42, 43, 44, 45, 46 and the electrode terminals 47, 48. The electrode terminals 41, 42, 43, 44, 45, and 46 are connected to the lower electrode substrate 20, and the electrode terminals 47 and 48 are connected to the upper electrode substrate 10. The upper electrode substrate 10 is made of a resin material. Since the lower electrode substrate 20 is made of glass or the like, the material forming the upper electrode substrate 10 and the material forming the lower electrode substrate 20 have different thermal expansion coefficients. For this reason, when the cut portion 49 is not formed, the joint portion between the flexible substrate 40 and the upper electrode substrate 10 and the lower electrode substrate 20 is peeled off due to the effects of thermal expansion and contraction, resulting in failure. There is. Therefore, by forming the cut portion 49 in the flexible substrate 40, the influence of thermal expansion and thermal contraction in the upper electrode substrate 10 and the lower electrode substrate 20 is alleviated, and durability in the touch panel is enhanced and reliability is enhanced. Can do.

  As shown in FIGS. 10 and 11, a transparent conductive film 13 made of ITO or the like is provided on the surface of the upper electrode substrate 10, and the film electrode terminal 11 and the film electrode 12 are provided on the transparent conductive film 13. Is provided. 11 is a cross-sectional view taken along the alternate long and short dash line 10A-10B in FIG.

  A transparent conductive film 21 made of ITO or the like is formed on the surface of the lower electrode substrate 20, and an insulating film 22 is formed on the transparent conductive film 21. The insulating film 22 is formed of a thermosetting or ultraviolet curing acrylic resin. On the insulating film 22, electrode terminals 31, 32, 33, 34, 35, and 36 and wirings 23 are formed. The electrode terminals 31, 32, 33, 34, 35, and 36 and the wiring 23 are formed by heat drying after screen printing using a silver paste. An insulating film 24 is formed on the wiring 23 and the like.

  In addition, the flexible substrate 40 is provided with seven copper wirings as wirings, and electrode terminals 41, 42, 43, 44, 45, 46, 47, 48 are formed by exposing a part of the copper wiring. It is formed.

  As described above, the electrode terminals 31, 32, 33, 34, 35, and 36 in the lower electrode substrate 20 and the electrode terminals 41, 42, 43, 44, 45, and 46 in the flexible substrate 40 are respectively corresponding electrode terminals. Are connected, and the film electrode terminal 11 in the upper electrode substrate 10 and the electrode terminals 47 and 48 in the flexible substrate 40 are connected. For example, in the case shown in FIG. 11, the film electrode terminal 11 provided on the upper electrode substrate 10 is connected to the electrode terminals 47 and 48 provided on the flexible substrate 40, and the electrode terminal provided on the lower electrode substrate 20. 31 is connected to an electrode terminal 41 provided on the flexible substrate 40, and an electrode terminal 32 provided on the lower electrode substrate 20 is connected to an electrode terminal 42 provided on the flexible substrate 40. Each electrode terminal 36 is connected to each other so that the electrode terminal 36 provided on 20 is connected to the electrode terminal 46 provided on the flexible substrate 40.

  In the touch panel in the present embodiment, a flexible substrate 40 is provided between the transparent conductive film 13 in the upper electrode substrate 10 and the transparent conductive film 21 in the lower electrode substrate 20, and the transparent conductive film in the upper electrode substrate 10 is provided. 13 and the transparent conductive film 21 on the lower electrode substrate 20 do not concentrate the electric field on the insulating film 22 or the like. Therefore, even when the electrode terminals 31, 32, 33, 34, 35, 36, etc. are formed of silver paste, silver ions do not migrate in the insulating film 22. Thereby, the insulation defect by the migration of silver ion does not generate | occur | produce in the insulating film 22, but durability and reliability in a touch panel can be improved.

  The electrode terminals 31, 32, 33, 34, 35, and 36 on the lower electrode substrate 20 and the electrode terminals 41, 42, 43, 44, 45, and 46 on the flexible substrate 40 are anisotropic conductive films (Anisotropic Conductive). Film: ACF) and bonded by thermocompression bonding. Similarly, the film electrode terminal 11 in the upper electrode substrate 10 and the electrode terminals 47 and 48 in the flexible substrate 40 are joined by thermocompression bonding using an anisotropic conductive film.

  In the touch panel in the present embodiment, upper electrode substrate 10 is formed of a transparent resin material. Therefore, when the temperature of thermocompression bonding is high, upper electrode substrate 10 is deformed or the like. For this reason, it is preferable to use so-called low temperature ACF as the anisotropic conductive film. The low temperature ACF is preferably one that can be thermocompression bonded at a temperature of 150 ° C. or lower, which is a temperature that does not deform the upper electrode substrate 10, and examples thereof include a low temperature ACF containing epoxy acrylate and the like. It is done.

  In the touch panel in the present embodiment, two electrode terminals 47 and 48 are formed on the flexible substrate 40 connected to the film electrode terminal 11 on the upper electrode substrate 10.

  As shown in FIG. 12, in the case of a wide electrode terminal such as the electrode terminal 311 in the flexible substrate 310, when the thermocompression bonding is performed through the anisotropic conductive film 320, the upper electrode substrate 10 is a film. Therefore, it is deformed at the time of thermocompression bonding and is thermocompression bonded in such a shape that the central portion of the anisotropic conductive film 320 is thick and the peripheral portion is thin. When thermocompression bonding is performed in such a shape, resistance may increase between the electrode terminal 311 in the flexible substrate 310 and the film electrode terminal 11 in the upper electrode substrate 10, and sufficient conductivity may not be obtained. .

  On the other hand, in the touch panel in the present embodiment, as shown in FIG. 13, in the flexible substrate 40, the electrode terminal connected to the film electrode terminal 11 in the upper electrode substrate 10 is separated into two electrode terminals 47 and 48. Is formed. For this reason, the anisotropic conductive film 60 can be connected in a substantially uniform thickness, and it is sufficient between the film electrode terminal 11 in the upper electrode substrate 10 and the electrode terminals 47 and 48 in the flexible substrate 40. Conductivity can be obtained.

  In this embodiment, a 7-wire type touch panel in which 7 wires are formed on the flexible substrate 40 has been described. However, in this embodiment, a flexible substrate on which 5 wires are formed is used. The present invention can be similarly applied to a linear touch panel, and can be applied to all touch panels in which electrodes are provided on both the upper electrode substrate and the lower electrode substrate.

[Second Embodiment]
Next, a second embodiment will be described. This embodiment includes the upper electrode substrate 10 and the lower electrode substrate 20 in the first embodiment, and uses a flexible substrate having a structure different from that of the first embodiment.

  Based on FIG. 14 and FIG. 15, the flexible substrate of the touch panel in this Embodiment is demonstrated. The flexible substrate 140 includes electrode terminals 141, 142, 143, 144, 145, 146 connected to the electrode terminals 31, 32, 33, 34, 35, 36 on the lower electrode substrate 20, and a film on the upper electrode substrate 10. Electrode terminals 147 and 148 connected to the electrode terminal 11 are provided.

  The electrode terminals 141, 142, 143, 144, 145, and 146 on the flexible substrate 140 are connected to the electrode terminals 31, 32, 33, 34, 35, and 36 provided on the lower electrode substrate 20. In FIG. Further, since the electrode terminals 147 and 148 in the flexible substrate 140 are connected to the film electrode terminal 11 in the upper electrode substrate 10, they are provided on the surface side in FIG. 14.

  As shown in FIG. 15, the copper wiring connected to the electrode terminals 147 and 148 in the flexible substrate 140 is formed on the copper wiring 151 formed on one surface of the polyimide film 150 that is an insulating film and on the other surface. The copper wiring 152 is electrically connected through a through hole 153 provided in the polyimide film 150. In addition, a polyimide film 154 which is an insulating film is formed on the surface of the copper wiring 151 formed on one surface of the polyimide film 150, and an insulating film is formed on the surface of the copper wiring 152 formed on the other surface. A certain polyimide film 155 is formed. Therefore, the electrode terminals 147 and 148 can be formed by removing the polyimide film 154 formed on one surface and exposing the copper wiring 151. In other copper wirings, electrode terminals 141, 142, 143, 144, 145, and 146 can be formed by removing the polyimide film formed on the other surface and exposing the copper wiring.

  The through hole 153 is formed by performing metal plating after forming an opening for connecting the copper wirings 151 and 152 in the polyimide film 150 with a drill or the like. Thereby, the copper wiring 151 formed on one surface of the polyimide film 150 and the copper wiring 152 formed on the other surface can be electrically connected.

  The contents other than the above are the same as in the first embodiment.

Example 1
The touch panel in Example 1 will be described.

  The touch panel in Example 1 is screen-printed using a silver paste on the upper electrode substrate 10 made of a PET (Polyethylene terephthalate) film having a thickness of 188 μm on which an ITO film is formed as the transparent conductive film 13 and then dried by heating. Thus, the film electrode terminal 11 and the film electrode 12 are formed.

  Next, a dot spacer (not shown) is formed on the surface of the lower electrode substrate 20 made of a glass substrate having a thickness of 1.1 mm with an ITO film formed as the transparent conductive film 21, and then the lower electrode substrate is formed. An insulating film 22 is formed around 20 by printing using an insulating resist. Further, on the insulating film 22, wiring 23 and electrode terminals 31, 32, 33, 34, 35, 36 are formed by screen printing using silver paste. Etc.

  Next, the upper electrode substrate 10 and the lower electrode substrate 20 are bonded to each other with the double-sided tape 51 in a state where the transparent conductive film 13 and the transparent conductive film 21 face each other, and then the film electrode provided on the upper electrode substrate 10 The terminal 11 and the electrode terminals 47 and 48 in the flexible substrate 40 are electrically connected by thermocompression bonding using a low temperature ACF, and the electrode terminals 31, 32, 33, 34, 35, 36 provided on the lower electrode substrate 20 The electrode terminals 41, 42, 43, 44, 45, and 46 provided on the flexible substrate 40 are electrically connected by thermocompression using a normal ACF. Thus, the touch panel in Example 1 was produced.

  When the initial characteristics of the touch panel of Example 1 were measured, both the electrical characteristics and the appearance were good.

  Further, when a high temperature and high humidity test (85 ° C., 85% RH, 1000 hours) was performed, the initial characteristics were maintained without change and good characteristics were obtained. Moreover, when the thermal shock test (-40 degreeC-+85 degreeC, each 0.5 hour, 1000 cycles) was done, the initial stage characteristic was maintained as it was.

(Comparative Example 1)
Next, the touch panel in Comparative Example 1 will be described.

  The touch panel in Comparative Example 1 is a film electrode obtained by screen-printing using silver paste on an upper electrode substrate 210 made of a PET film having a thickness of 188 μm with an ITO film as the transparent conductive film 212, and drying by heating. 211 and the like are formed.

  Next, a dot spacer (not shown) is formed of a photoresist on the surface of a lower electrode substrate 220 made of a glass substrate having a thickness of 1.1 mm, on which an ITO film is formed as the transparent conductive film 221, and thereafter, the lower electrode substrate An insulating film 222 is formed around 220 by printing using an insulating resist, and further, connection terminals 231, wirings 232, electrode terminals 233, 234, 235, 236, 237, 238, by screen printing using silver paste. 239 and the like are formed.

  Next, the upper electrode substrate 210 and the lower electrode substrate 220 are bonded to each other with a double-sided tape 251 in a state where the transparent conductive film 212 and the transparent conductive film 221 face each other, and then the film electrode provided on the upper electrode substrate 210 211 and a connection terminal formed on the lower electrode substrate 220 are electrically connected by a conductive adhesive, and the electrode terminals 233, 234, 235, 236, 237, 238, 239 provided on the lower electrode substrate 220 are flexible. The electrode terminals 243, 244, 245, 246, 247, 248, and 249 provided on the substrate 240 are electrically connected by thermocompression using a normal ACF. Thus, the touch panel in Comparative Example 1 was produced.

  When the initial characteristics of the touch panel in Comparative Example 1 were measured, both the electrical characteristics and the appearance were good.

  Further, when a high temperature and high humidity test (85 ° C., 85% RH) was performed, the insulation between the upper electrode substrate 210 and the lower electrode substrate 220 decreased to 5 kΩ in 200 hours, and normal coordinate detection was performed. The function as a touch panel was lost. When the cause was investigated, the film electrode 211 provided on the upper electrode substrate 210 and the connection terminal formed on the lower electrode substrate 220 are short-circuited at the portion of the insulating film 222 connected by the conductive adhesive. There was found. This is presumably caused by migration of silver ions in the insulating film 222.

  As described above, in the touch panel in Example 1, migration of silver ions in the insulating film does not occur, so that insulation failure does not occur and the flexible substrate 40 and the upper part are not affected by thermal expansion and contraction. The electrical connection between the electrode substrate 10 and the lower electrode substrate 20 is maintained. Therefore, the touch panel has high durability and reliability.

  As mentioned above, although the form which concerns on implementation of this invention was demonstrated, the said content does not limit the content of invention.

DESCRIPTION OF SYMBOLS 10 Upper electrode substrate 11 Film electrode terminal 12 Film electrode 13 Transparent conductive film 20 Lower electrode substrate 21 Transparent conductive film 22 Insulating film 23 Wiring 24 Insulating films 31, 32, 33, 34, 35, 36 Electrode terminal 40 Flexible substrates 41, 42 , 43, 44, 45, 46, 47, 48 Electrode terminal 49 Notch 51 Double-sided tape

Claims (7)

An upper electrode substrate having an upper conductive film;
A lower electrode substrate having a lower conductive film;
A flexible substrate having an electrode terminal connected to an electrode terminal provided on the upper electrode substrate and an electrode terminal connected to an electrode terminal provided on the lower electrode substrate;
Have
The electrode terminal provided on the upper electrode substrate and the electrode terminal provided on one surface of the flexible substrate are electrically connected by thermocompression bonding, and the electrode terminal provided on the lower electrode substrate and the flexible terminal A touch panel, which is electrically connected to an electrode terminal provided on the other surface of the substrate by thermocompression bonding.   The touch panel according to claim 1, wherein the upper electrode substrate is made of a transparent resin material.   3. The flexible substrate, wherein a cut portion is provided between an electrode terminal connected to the upper electrode substrate and an electrode terminal connected to the lower electrode substrate. Touch panel as described in 1.   The thermocompression bonding between the electrode terminal provided on the upper electrode substrate and the electrode terminal provided on one surface of the flexible substrate is performed at a temperature of 150 ° C. or less. 4. The touch panel according to any one of 3.   A plurality of electrode terminals provided on one surface of the flexible substrate connected to electrode terminals provided on the upper electrode substrate are provided for one electrode terminal on the upper electrode substrate. The touch panel according to any one of claims 1 to 4.   The flexible substrate has metal films formed on both sides of an insulating film, and the metal films formed on both sides of the insulating film are electrically connected through through holes provided in the insulating film. The touch panel according to claim 1, wherein the touch panel is a touch panel.   The touch panel according to any one of 1 to 6, wherein the number of wirings provided on the flexible substrate is five or seven.

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