JP4536136B2 - Touch panel - Google Patents

Description

  The present invention relates to a pen input panel and a touch panel used for inputting to a personal computer, a word processor, an electronic notebook, and the like.

A resistive film type touch panel used on a display device such as an LCD, PDP, CRT, etc. has two transparent panels each having a transparent conductive film attached to a transparent substrate, and the conductive film sides face each other. Insulating spacers are arranged in the form of dots, electrodes are formed on the respective conductive films, circuits are connected, and one side of the substrate is pressed with a pen or finger to establish vertical conduction. The coordinates are detected by taking them.
Touch panels are being used in large quantities in a wider range of fields that are not associated with the development of electronic devices, and as a result, touch panels that can be manufactured more easily and more durable touch panels are strongly demanded. ing.

For example, two panels have a combination of top / bottom film / glass, film / plastic plate, film / film, etc., and the conductive film material is ITO (indium oxide / tin oxide) or tin oxide (SnO). ₂ ) is used, but it is necessary to divide the conductive film into the desired pattern and attach it to the surface of the substrate. Conventionally, the conductive film is deposited on the entire surface of the substrate by sputtering or the like and then etched. Thus, unnecessary portions have been removed.

  As the etching method, a photolithography method or a sand blast method is used, but the photolithography method uses a wet method using a liquid such as aqua regia or hydrochloric acid depending on the etching material, hydrofluoric acid (HF) or fluoriodic acid. There is a dry method using a gas such as (HI). The wet method has many processes such as application of photosensitive resin, drying, exposure development with a photomask, and drying. Also, in order to use dangerous liquids such as aqua regia and hydrochloric acid, liquid management and waste liquid treatment In addition, since the dry method uses dangerous gases such as hydrofluoric acid and fluoriodic acid, it requires a lot of capital investment for measures against gas leakage and exhaust gas treatment. .

  In addition, there is a method to remove unnecessary parts by sandblasting, but this method takes time, the mask that covers the necessary parts needs to be replaced frequently, and the management man-hour is large. There is also a problem that the strength is lowered due to scratching. Accordingly, there is a strong demand for a touch panel having a conductive film that is divided by simple work with low equipment costs.

  In addition, the upper / lower panel of the touch panel is bonded by double-sided tape at the periphery, but when the surface is pressed, it may be damaged by the edge of this double-sided tape and will not be damaged. A highly durable touch panel is required.

  In many cases, an optical member is attached to the surface of the touch panel via an adhesive layer, but the two may be peeled off when a foreign object or a bubble is attached during the operation. At that time, the touch panel and the optical member may be damaged and reattachment may not be possible. Therefore, in such a case, a touch panel to which an optical member is attached so as to be able to be attached again is sought.

  An object of this invention is to provide the touchscreen which divided | segmented the electrically conductive film adhering on a board | substrate with the simple method in view of the said problem.

According to the first aspect of the present invention, a pair of panels each having a transparent conductive film attached to one side of a transparent substrate are joined to each other with a double-sided tape, and the electrically insulating side is opposed to the conductive film side. In a touch panel that is arranged via a spacer,
A plurality of electrode circuits connected to separate external conductors are provided on the conductive film of one substrate, and the plurality of electrode circuits distributes power on opposite sides of one substrate; An electrode circuit for distributing power on the opposite side of the other substrate disposed adjacent to the substrate,
In order to prevent the adjacent electrode circuits from being short-circuited with each other, a groove is formed by etching with a laser in the conductive film between the adjacent electrode circuits, and each region of the conductive film in which each electrode circuit is arranged is formed. Split each other,
An electrode circuit for distributing power on the opposite side of at least one other substrate is surrounded by the groove except for a connection portion with an external electric wire,
A hole is formed in the double-sided tape to conduct from the electrode circuit provided on the conductive film of one substrate to the electrode circuit provided on the conductive film of the other substrate, and a conductive substance is disposed in the hole. A touch panel is provided.

According to the second aspect of the present invention, a closed groove that circulates along the outer periphery is formed so that the region where the electrode circuit is provided is not exposed to the side end face.
In the invention of claim 3, the double-sided tape covers the groove.

According to the present invention, a pair of panels each having a transparent conductive film attached to one surface of a transparent substrate are joined to each other through a double-sided tape, and the electrically insulating spacer is disposed so that the conductive film side faces each other. In the touch panel arranged via, a plurality of electrode circuits connected to separate external conductors are provided on the conductive film of one substrate, and the plurality of electrode circuits are opposite sides of one substrate. Even when an electrode circuit for power distribution is included and an electrode circuit for power distribution on the opposite side of the other substrate disposed adjacent to the electrode circuit, the short circuit between the electrode circuits is prevented. Thus, it is possible to distribute power to each electrode circuit satisfactorily.
At that time, the conductive film can be divided quickly with simple equipment without using dangerous chemicals or gases, so that the cost is remarkably low.

Hereinafter, embodiments of a touch panel according to the present invention will be described with reference to the accompanying drawings.
In the following description, the movable side panel means a substrate far from the display device pressed by a pen or a finger, and the fixed side panel means a substrate near the display device.
The front side means the input side, and the back side means the display device side.

  FIG. 1 is a view of the fixed side panel 100 of the touch panel according to the first embodiment of the present invention as viewed from the front side. The fixed side panel 100 is electrically conductive with ITO on the front side of a glass substrate 110 (see FIG. 4). After the film 120 (see FIG. 4) is deposited by sputtering, it is etched by a laser to form grooves 131, 132, 133, 134, 135 (shown by thick solid lines), and then dot spacers 140 are formed by screen printing. Further, silver electrode circuits 151, 152, 153, 154, 155, and 156 are additionally provided by printing. The grooves 1311 to 135 are formed so that regions of the conductive film 120 to which the electrode circuits 151, 152, 153, 154, 155, and 156 are connected are divided as desired.

  FIG. 2 is a view of the movable panel 200 as viewed from the front side, and an ITO conductive film 220 (see FIG. 4) is attached to the back side of a transparent resin film substrate 210 (see FIG. 4) by sputtering. Later, silver electrode circuits 251 and 252 are attached and formed by printing.

  FIG. 3 is a view of a double-sided tape 300 interposed between the fixed side panel 100 and the movable side panel 200 and joining the fixed side sub-panel 100 and the movable side panel 200 as viewed from the front side. The fixed side panel 100 and the movable side panel 200 shown in FIGS. Reference numerals 301 and 302 indicate holes, which are provided with a conductive adhesive, and are connected to the electrode circuit 156 of the fixed side panel 100, the electrode circuit 252 of the movable side panel 200, and the fixed side. The electrode circuit 154 of the panel 100 is electrically connected to the electrode circuit 251 of the movable side panel 200.

  4 is a cross-sectional view of the state in which the fixed side panel 100 and the movable side panel 200 are joined by the double-sided tape 300, taken along the plane AA in FIG. The double-sided tape 300 is one in which an adhesive is applied to both sides of a thin film, but is shown integrally. In addition, since the adhesive is soft, the electrode circuits 152 and 153 enter the adhesive.

  In the first embodiment of the present invention, the fixed-side panel 100 is made as described above, and the conductive film 120 of the fixed-side panel 100 is divided by forming the grooves 131 to 135 using a laser. Compared to the photolithographic method as described above, it can be manufactured easily in a much shorter time, and the equipment for splitting the conductive film is only one laser device and much less than the photolithographic method. Tesumu. Further, since no dangerous liquid or gas is used, it is safe, and man-hours and facilities for managing and processing them are not required.

  In addition, since the photolithographic method uses a photomask, it is necessary to prepare another photomask for changing the division pattern. However, when the laser is used as in the present invention, the movement of the laser is controlled. Therefore, it can be done in a short time just by changing the software.

  Further, since the conductive film cannot be finely removed by the conventional technique as described above, it is necessary to remove the conductive film widely as shown by the hatched area in FIG. 5, and the fixing is performed as shown in FIG. The side panel 100 and the movable side panel 200 are joined.

As a laser for performing etching, a YAG laser is used in this embodiment, but a YLF laser, a YVO laser, a CO ₂ laser, or the like can also be used. As the laser light, light in the infrared region having a wavelength of 900 nm or more is preferably used, and the pulse width is preferably set to sub-nanosecond or less so as not to leave the thermal metamorphic layer in the conductive film 120. In addition, a larger laser spot diameter can surely form a groove in the conductive film 120, but if it is too large, energy is dispersed and sharp etching cannot be performed, so that the diameter is 0.1 mm to 2.0 mm. Is preferably used.

  A power connector (not shown) is attached to the fixed side panel 100 of the touch panel completed as described above in FIG. 1B. As shown in the figure, the electrode circuits 153, 154, 155, 156 For example, voltages of 5 volts, 0 volts, 0 volts, and 5 volts are applied, respectively. When the front side of the movable side panel 200 is pressed, the resistance is measured through the electrodes, the coordinate position is detected and input as input information to a control device (not shown), but the configuration is related to the present invention. Since there is no, explanation is omitted.

  Next, a modification of the first embodiment will be described. This is because the conductive film 120 of the fixed-side panel 100 and the conductive film 220 of the movable-side panel 200 each extend to the outer peripheral end face, so that foreign matter adheres to bridge the conductive film 120 and the conductive film 220 at the end face. Then, there is a possibility of short-circuiting, so that such a thing will not occur.

  FIG. 7 is a diagram showing the fixed-side panel 100 in a modification of the first embodiment, and a closed groove 136 that goes around the outer circumference is added to the first embodiment. Yes. FIG. 8 is a sectional view taken along the line A ″ -A ″ of FIG. By doing so, the region including the end face is not electrically connected to the region where the power supply circuit is disposed, so that the short circuit as described above does not occur.

  As described above, the formation of the groove by laser etching has been described for the case where the groove is formed on the glass substrate 110 of the fixed side panel 100 on the conductive film 120. However, the groove formation by the laser etching is performed on the movable side panel 200. The present invention can also be applied to a substrate formed of a film like the substrate 210 of FIG.

  Next, a second embodiment will be described. This prevents the conductive film 220 of the movable side panel 200 from being damaged by the double-sided tape 300. In addition, since the adhesive of the double-sided tape 300 is soft, it is the film (not shown) to which the adhesive panel is applied that damages the movable side panel 200.

  FIG. 9 is a diagram for explaining the characteristics of the second embodiment, and a rubber elastic member 500 is provided on the movable side panel 200 so as to cover the portion of the movable side panel 200 that the edge of the double-sided tape 300 hits. It is attached. By doing so, the edge of the double-sided tape 300 is prevented from hitting the conductive film 220 of the movable side panel 200, and the conductive film 220 is prevented from being damaged.

  FIG. 10 shows a first modification of the second embodiment, which corresponds to the case where an insulating layer 400 is provided between the fixed side panel 100 and the double-sided tape 300, and the elastic member 500 is provided on the inner side. Thus, the edge of the insulating layer 400 is prevented from hitting the conductive film 220 of the movable side panel 200.

  FIG. 11 shows a second modification of the second embodiment in which the elastic member 500 is attached to the double-sided tape 300 instead of the movable panel 200. FIG. 12 shows the second embodiment. This is a third modification of the embodiment and corresponds to the case where the insulating layer 400 is provided by the same method. Thus, even if the elastic member 500 is attached not to the movable side panel 200 but to the double-sided tape 300, the conductive film 220 can be prevented from being damaged.

  The above-described second embodiment and its modification have been described by taking, as an example, the case where the conductive film is divided by a groove formed by laser etching as in the first embodiment. However, since the characteristic part is the structure as described above, the application range is not limited to the case where the conductive film is divided as in the first embodiment. It will be easily understood that the present invention can also be applied to the case where the conductive film is divided by a photolithography method or a sand blast method.

Next, a third embodiment will be described. First, the background will be described in detail.
In order to prevent reflection on the surface of the touch panel and improve visibility, an optical member such as a polarizing plate, a retardation plate, or a circular polarizing plate is provided on the front side of the movable side panel 200 or the back side of the fixed side panel 100. Is often attached via an adhesive layer. During this operation, foreign matter or bubbles may be mixed. In such a case, the optical member may be peeled off from the surface of the movable side panel 200 or the fixed side panel 100 and the operation may be repeated again. However, if the adhesive force of the adhesive layer is inappropriate, the residue may remain on the surface of the optical member, the movable side panel 200, and the fixed side panel 100, and when peeling, the optical member, the movable side panel 200, and the fixed side The panel 100 may be damaged, and these may not be reused and the yield may be deteriorated.

The third embodiment of the present invention addresses such a problem, and the pressure-sensitive adhesive layer is a re-peelable pressure-sensitive adhesive layer having just good adhesive force that does not cause the above-described problems.
FIG. 13 is a cross-sectional view of the touch panel according to the third embodiment. A quarter-wave plate 710 and a polarizing plate 720 are laminated in advance on the front side of the movable side panel 200 via a removable adhesive layer 600a. An optical member 700a made of a quarter-wave plate 710 is attached to the back side of the fixed panel 100 via a removable adhesive layer 600b.

  The adhesive layer 600a has a 90-degree peeling adhesive force of 5 g to 500 g / 25 mm with respect to the substrate 210 of the resin film of the movable side panel 200. Further, the adhesive layer 600b has a 90-degree peeling adhesive force to the glass substrate 110 of the fixed side panel 100 of 5 g to 500 g / 25 mm. The 90-degree peel adhesive strength of 500 g / 25 mm means that the force required to pull a 25 mm width in a direction perpendicular to the adhesive surface is 500 g.

  The re-peelable pressure-sensitive adhesive layer is preferably formed of an ethylene vinyl alcohol-based pressure-sensitive adhesive, a polyacrylic ester-based pressure-sensitive adhesive, a polymethacrylic ester-based pressure-sensitive adhesive, or a silicon-based pressure-sensitive adhesive, The transmittance is preferably 75% or more (JISZ8722) in the visible light region.

  By making the adhesive layer as a removable adhesive layer as described above, the optical members 700a and 700b, or the movable panel 200 and the fixed panel 100 are damaged or the adhesive remains when peeling. This is prevented and the yield is improved.

  The third embodiment has been described by taking as an example the case where the conductive film is divided by a groove formed by laser etching as in the first embodiment. Since the characteristic part of this form is the structure as described above, its application range is not limited to the case where the conductive film is divided as in the first embodiment. For example, it will be easily understood that the present invention can be applied to a case where the conductive film is divided by a photolithography method or a sand blast method.

It is a figure which shows the stationary side panel in the 1st Embodiment of this invention. It is a figure which shows the movable side panel in the 1st Embodiment of this invention. In the 1st Embodiment of this invention, it is a figure which shows the double-sided tape interposed between a fixed side panel and a movable side panel. In the 1st Embodiment of this invention, it is sectional drawing which cut the state which joined the fixed side panel and the movable side panel with the double-sided tape with the surface which passes along the AA line of FIG. It is a figure which shows the removal range of the electrically conductive film of the stationary side panel in a prior art. FIG. 6 is a cross-sectional view of the state in which the fixed side panel from which the conductive film has been removed is joined to the movable side panel with a double-sided tape as shown in FIG. It is a figure which shows the stationary side panel in the 1st modification of the 1st Embodiment of this invention. It is sectional drawing which cut the state which joined the fixed side panel of FIG. 7 with the movable side panel with the double-sided tape by the surface which passes along A "-A" line of FIG. It is a figure which shows the characteristic of 2nd Embodiment. It is a figure which shows the characteristic of the 1st modification of 2nd Embodiment. It is a figure which shows the characteristic of the 2nd modification of 2nd Embodiment. It is a figure which shows the characteristic of the 3rd modification of 2nd Embodiment. It is a figure explaining 3rd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Fixed side panel 110 Glass substrate 120 (ITO) conductive film 131,132,133,134,135,136 groove | channel (formed by laser etching) 140 spacer 151,152,153,154,155 (made of silver) electrode circuit 200 Movable side panel 210 Film substrate 220 (ITO) conductive film 251,252 (made of silver) electrode circuit 300 double-sided tape 301,302 hole 400 insulating layer 500 (rubber) elastic member 600a, 600b adhesive layer 700a, 700b Optical member

Claims (3)

A touch panel in which a pair of panels each having a transparent conductive film attached to one surface of a transparent substrate are joined via a double-sided tape and disposed via an electrically insulating spacer so that the conductive film side faces each other. In
A plurality of electrode circuits connected to separate external conductors are provided on the conductive film of one substrate, and the plurality of electrode circuits distribute power on opposite sides of one substrate; An electrode circuit for distributing power on the opposite side of the other substrate disposed adjacent to the substrate,
In order to prevent the adjacent electrode circuits from being short-circuited with each other, a groove is formed by etching with a laser in the conductive film between the adjacent electrode circuits, and each region of the conductive film in which each electrode circuit is arranged is formed. Split each other,
At least one electrode circuit for power distribution on the opposite side of the other substrate is surrounded by the groove except for a connection portion with an external electric wire,
A hole is formed in the double-sided tape to conduct from the electrode circuit provided on the conductive film of one substrate to the electrode circuit provided on the conductive film of the other substrate, and a conductive substance is disposed in the hole. Yes,
A touch panel characterized by that.   2. The touch panel according to claim 1, wherein a closed groove is formed around the outer periphery so that a region where the electrode circuit is provided is not exposed to the side end face.   The touch panel according to claim 1, wherein the double-sided tape covers the groove.

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