JP2007316705A - Touch panel and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a touch panel with satisfactory visibility and easy operability, as to the touch panel used for various kinds of electronic equipment, and a manufacturing method therefor. <P>SOLUTION: Oxygen and nitrogen are released less from an upper substrate 11 even when used under a high temperature condition, by using one with oxygen and nitrogen replaced with moisture by humidification, as the upper substrate 11 formed with an upper conductive layer 3 on an under face and stuck with a polarizing plate 6 on an upper face, the substituted moisture is discharged to an outside through the polarizing plate 6, to prevent generation of bubbles in an adhesive layer 7, and to obtain the touch panel with satisfactory visibility and easy operability. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a touch panel mainly used for operation of various electronic devices and a manufacturing method thereof.

  In recent years, as various electronic devices such as mobile phones and car navigation systems have become more sophisticated and diversified, a light-transmissive touch panel is attached to the front surface of a display element such as a liquid crystal display, and the display element on the rear side is passed through this touch panel. There is an increasing number of devices that switch each function of a device by pressing the touch panel with a finger or a pen while visually recognizing the display, and there is a demand for a device that has excellent visibility and is easy to operate.

  Such a conventional touch panel will be described with reference to FIG.

  In addition, in order to make the structure easy to understand, the drawing shows an enlarged dimension in the thickness direction.

  FIG. 2 is a cross-sectional view of a conventional touch panel. In FIG. 2, 1 is a film-like upper substrate such as a light-transmitting polycarbonate, 2 is a light-transmitting lower substrate, and the lower surface of the upper substrate 1 is oxidized. A light-transmissive upper conductive layer 3 such as indium tin is formed on the upper surface of the lower substrate 2, and a lower conductive layer 4 is also formed on the upper surface.

  A plurality of dot spacers (not shown) are formed on the upper surface of the lower conductive layer 4 by an insulating resin at predetermined intervals, and a pair of upper electrodes (not shown) are formed at both ends of the upper conductive layer 3. At both ends of the lower conductive layer 4, a pair of lower electrodes (not shown) perpendicular to the upper electrode are formed.

  Reference numeral 5 denotes a frame-like spacer, and the outer periphery of the upper substrate 1 and the lower substrate 2 is bonded to each other by an adhesive (not shown) applied to the upper and lower surfaces or one surface of the spacer 5. The lower conductive layer 4 opposes with a predetermined gap.

  Further, 6 is a polarizing plate in which triacetyl cellulose or the like is laminated on the upper and lower surfaces of polyvinyl alcohol in which iodine or a dye is oriented. This polarizing plate 6 is adhered to the upper surface of the upper substrate 1 by an adhesive layer 7 to constitute a touch panel. Has been.

  The touch panel configured in this manner is disposed on the front surface of a liquid crystal display element or the like and attached to an electronic device, and a pair of upper and lower electrodes are connected to an electronic circuit (not shown) of the device. .

  In the above configuration, when the upper surface of the polarizing plate 6 is pressed with a finger or a pen while visually recognizing the display of the liquid crystal display element on the back of the touch panel, the upper substrate 1 is bent together with the polarizing plate 6 and the upper conductive layer is pressed. 3 contacts the lower conductive layer 4.

  Then, a voltage is sequentially applied from the electronic circuit to the upper electrode and the lower electrode, and the electronic circuit detects the pressed portion by the voltage ratio between these electrodes, and various functions of the device are switched.

  At this time, when external light such as sunlight and lamps from above passes through the polarizing plate 6, the light wave in the X direction and the Y direction perpendicular to the X direction is a straight line only in one direction by the polarizing plate 6. It becomes polarized light and enters the upper substrate 1 from the polarizing plate 6.

  Then, this light passes through the upper substrate 1 and is reflected upward by the lower conductive layer 4. Since this reflected light is substantially halved by the polarizing plate 6 as described above, it is reflected from the upper surface of the polarizing plate 6. Therefore, the liquid crystal display element on the back surface is easy to see.

As prior art document information related to the invention of this application, for example, Patent Document 1 is known.
JP 2006-107015 A

  However, in the conventional touch panel, when the surroundings are used at a high temperature, such as in an automobile room under direct sunlight, the upper substrate 1 is easy to adsorb oxygen and nitrogen, and the upper conductive material on the lower surface thereof. Since the layer 3 and the polarizing plate 6 affixed to the upper surface are difficult to pass gas or the like, as shown in FIG. 2, oxygen and nitrogen released from the upper substrate 1 due to heat are absorbed by the upper substrate 1 and the polarizing plate. 6 is accumulated in the adhesive layer 7 between 6 and bubbles 8 are generated, and external light is reflected on the bubbles 8 to make it difficult to see the liquid crystal display element on the back surface and the visibility is impaired.

  The present invention solves such a conventional problem, and an object of the present invention is to provide a touch panel with good visibility by preventing the generation of bubbles and the like even when used at high temperatures.

  In order to achieve the above object, the present invention has the following configuration.

  According to the first aspect of the present invention, a touch panel is configured by using an upper substrate in which an upper conductive layer is formed on the lower surface and a polarizing plate is attached on the upper surface, in which oxygen and nitrogen inside are replaced with moisture. Even when used in a high temperature state, the release of oxygen and nitrogen from the upper substrate is reduced, and moisture substituted for these is released to the outside through the polarizing plate. It has an effect that a touch panel with good visibility can be obtained by preventing the generation of bubbles in the inside.

  According to the second aspect of the present invention, the upper substrate on which the upper conductive layer is formed is humidified, and then the lower substrate is pasted on the lower surface and the polarizing plate is pasted on the upper surface to produce the touch panel according to the first aspect. There is an effect that a touch panel with good visibility can be realized by a simple method.

  As described above, according to the present invention, it is possible to obtain an advantageous effect that it is possible to realize a touch panel with good visibility and easy operation, and a manufacturing method thereof.

  Hereinafter, an embodiment of the present invention will be described with reference to FIG.

  In addition, in order to make the structure easy to understand, the drawing shows an enlarged dimension in the thickness direction.

  Further, the same reference numerals are given to the same components as those described in the background art section, and the detailed description will be simplified.

(Embodiment)
FIG. 1 is a cross-sectional view of a touch panel according to an embodiment of the present invention. In FIG. 1, reference numeral 11 denotes a film-like transparent substrate such as polyethersulfone or polycarbonate, and the upper substrate 11 is humidified or the like. Is used in which oxygen and nitrogen inside are replaced by moisture.

  Reference numeral 2 denotes a light-transmitting lower substrate such as glass, acrylic, or polycarbonate, and a light-transmitting upper conductive layer 3 such as indium tin oxide or tin oxide is formed on the lower surface of the upper substrate 11. Similarly, the lower conductive layer 4 is formed by sputtering or the like.

  A plurality of dot spacers (not shown) are formed on the upper surface of the lower conductive layer 4 by an insulating resin such as epoxy or silicon at a predetermined interval, and a pair of silver, carbon, or the like is formed at both ends of the upper conductive layer 3. A pair of lower electrodes (not shown) perpendicular to the upper electrode are formed at both ends of the lower conductive layer 4.

  Further, reference numeral 5 denotes a frame-like spacer such as polyester or epoxy, and an adhesive (not shown) such as acrylic or rubber applied and formed on the upper and lower surfaces or one surface of the spacer 5 to fix the upper substrate 11 and the lower substrate 2. The outer periphery is bonded, and the upper conductive layer 3 and the lower conductive layer 4 face each other with a predetermined gap.

  Reference numeral 6 denotes a flexible polarizing plate in which triacetyl cellulose or the like is laminated on the upper and lower surfaces of polyvinyl alcohol which has been adsorbed with iodine or a dye and stretched / oriented. This polarizing plate 6 is an adhesive layer made of acrylic or rubber. 7 is attached to the upper surface of the upper substrate 11 to constitute a touch panel.

  In order to manufacture such a touch panel, first, the upper substrate 11 on which the upper conductive layer 3 is formed is cut into a predetermined size, and then, for example, this is placed in a high temperature and high humidity tank of 90 to 95% RH at around 40 degrees. By storing in a heated and humidified state at a predetermined temperature and humidity, such as 24 hours, large molecules of oxygen and nitrogen in the upper substrate 11 are released, and the upper substrate 11 in which these are replaced by small molecules of water is released. To manufacture.

  Then, the polarizing plate 6 is attached to the upper surface of the upper substrate 11 by the adhesive layer 7, and the lower surface of the upper substrate 11 and the outer periphery of the upper surface of the lower substrate 2 are bonded together with the adhesive of the spacer 5 to complete the touch panel.

  At this time, since oxygen and nitrogen in the upper substrate 11 are replaced with moisture, oxygen and nitrogen in the atmosphere will not be re-adsorbed suddenly even if left at room temperature for about 24 hours. Then, the upper substrate 11 and the polarizing plate 6 are pasted in several hours, and the upper and lower surfaces of the upper substrate 11 are covered with the polarizing plate 6 and the upper conductive layer 3 that are difficult for gas to pass through. It is preferable to prevent adsorption.

  The touch panel configured in this manner is disposed on the front surface of a liquid crystal display element or the like and attached to an electronic device, and a pair of upper and lower electrodes are connected to an electronic circuit (not shown) of the device. .

  In the above configuration, when the upper surface of the polarizing plate 6 is pressed with a finger or a pen while visually recognizing the display of the liquid crystal display element on the back of the touch panel, the upper substrate 11 is bent together with the polarizing plate 6 and the upper conductive layer is pressed. 3 contacts the lower conductive layer 4.

  Then, a voltage is sequentially applied from the electronic circuit to the upper electrode and the lower electrode, and the electronic circuit detects the pressed portion by the voltage ratio between these electrodes, and various functions of the device are switched.

  At this time, when the external light such as sunlight and lamps from above passes through the polarizing plate 6, among the light waves in the X direction and the Y direction perpendicular thereto, for example, the polarizing plate 6 is a light wave in the Y direction. Is absorbed in the X direction, and enters the upper substrate 11 from the polarizing plate 6.

  Then, this light passes through the upper substrate 11 and is reflected upward by the lower conductive layer 4. Since this reflected light is substantially halved by the polarizing plate 6 as described above, it is reflected from the upper surface of the polarizing plate 6. The liquid crystal display element on the back is easy to see.

  Further, as described above, the upper substrate 11 is made by replacing oxygen and nitrogen with moisture, so that release of oxygen and nitrogen due to heat is reduced, and the substituted moisture is polyvinyl alcohol of the polarizing plate 6 or the like. Since it is emitted to the outside through the air, bubbles are not easily generated in the adhesive layer 7 even when the surroundings are used at a high temperature such as in an automobile under direct sunlight. It is designed not to impair sex.

  As described above, according to the present embodiment, by using the upper substrate 11 having the upper conductive layer 3 formed on the lower surface and the polarizing plate 6 attached on the upper surface, oxygen and nitrogen are replaced by moisture by humidification. Even when used in a high temperature state, the release of oxygen and nitrogen from the upper substrate 11 is reduced, and the substituted water is released to the outside through the polarizing plate 6. It is possible to obtain a touch panel that prevents generation of bubbles and the like, has good visibility, and is easy to operate, and a manufacturing method thereof.

  In the above description, a polarizing plate 6 is attached to the upper surface of the upper substrate 11 to prevent only reflection of external light from above, but a so-called linearly polarized light type is described. The present invention also applies to a so-called circularly polarized light type in which a quarter-wave retardation plate is provided between the lower substrate 2 and the lower surface of the lower substrate 2 to improve the visibility of a liquid crystal display element on the back surface in addition to reflection of external light. Can be implemented.

  The touch panel according to the present invention has an advantageous effect that it can provide an easy-to-operate device with good visibility, and is mainly useful for operating various electronic devices.

Sectional drawing of the touchscreen by one embodiment of this invention Cross-sectional view of a conventional touch panel

Explanation of symbols

2 Lower substrate 3 Upper conductive layer 4 Lower conductive layer 5 Spacer 6 Polarizing plate 7 Adhesive layer 11 Upper substrate

Claims (2)

A light transmissive upper substrate having an upper conductive layer formed on the lower surface, a light transmissive lower substrate having an upper conductive layer formed on the upper surface and facing the upper conductive layer with a predetermined gap therebetween, and the upper substrate A touch panel comprising a polarizing plate attached to the upper surface, wherein oxygen and nitrogen in the upper substrate are replaced with moisture. The touch panel manufacturing method according to claim 1, wherein after the upper substrate on which the upper conductive layer is formed is humidified, the lower substrate is pasted on the lower surface and the polarizing plate is pasted on the upper surface.

Images