JP5617570B2 - Touch panel - Google Patents

Description

  The present invention relates to a touch panel used mainly for operating various electronic devices.

  In recent years, as various electronic devices such as mobile phones and electronic cameras have become highly functional and diversified, a light-transmissive touch panel is mounted on the front surface of a display element such as a liquid crystal display element, and the display element on the back side is attached through this touch panel. There are an increasing number of devices that switch various functions of a device by touching the touch panel with a finger or the like while viewing the display, and there is a demand for a device that can be easily and reliably operated.

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

  In addition, in this drawing, in order to make the configuration easy to understand, the dimensions are partially enlarged.

  FIG. 6 is an exploded perspective view of a conventional touch panel. In FIG. 6, reference numeral 1 denotes a film-like light transmissive upper substrate having a thickness of about 50 to 125 μm, and the upper surface is light transmissive such as indium tin oxide. A plurality of upper conductive layers 2 made of silver, carbon, or the like, each having a substantially strip-like shape, arranged in the left-right direction, one end connected to the end of the upper conductive layer 2 and the other end extending to the front end of the outer periphery. However, the upper conductive layer 2 is formed to extend in the front-rear direction orthogonal to the upper conductive layer 2.

  Similarly, reference numeral 4 denotes a film-like light-transmitting lower substrate having a thickness of about 50 to 125 μm, and a plurality of light-transmitting, substantially band-like lower conductive layers 5 such as indium tin oxide on the upper surface. A plurality of lower electrodes 6 such as silver and carbon whose one end is connected to the end of the lower conductive layer 5 and the other end extends to the front end of the outer periphery are formed in the lower conductive layer 5. And extending in the front-rear direction of the parallel direction.

  Furthermore, 7 is a plate-like or film-like light-transmitting cover substrate having a thickness of around 0.3 to 2 mm. The upper substrate 1 is overlaid on the upper surface of the lower substrate 4, and the cover substrate 7 is overlaid on the upper surface of the upper substrate 1. These are each bonded by an adhesive (not shown) or the like to constitute a touch panel.

  The touch panel configured as described above is disposed on the front surface of a display element such as a liquid crystal display element and attached to an electronic device, and a plurality of upper electrodes 3 and lower electrodes 6 extending to the front end of the outer periphery are flexible wirings. It is electrically connected to an electronic circuit (not shown) of the device via a board, a connector (not shown) or the like.

  In the above configuration, when a voltage is sequentially applied from the electronic circuit to the plurality of upper electrodes 3 and the lower electrodes 6, when the upper surface of the cover substrate 7 is touched with a finger or the like according to the display on the display element on the back surface of the touch panel, Since the electrostatic capacity between the upper conductive layer 2 and the lower conductive layer 5 in the operated part changes, the electronic circuit detects the operated part, and various functions of the device are switched.

  That is, for example, when a finger or the like is touched on the upper surface of the cover substrate 7 on a desired menu in a state where a plurality of menus or the like are displayed on the display element on the back, a part of the charge is conducted to the finger, The capacitance between the upper conductive layer 2 and the lower conductive layer 5 of the touch panel is changed, and the electronic circuit detects the capacitance so that a desired menu can be selected.

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

JP 2009-93397 A

  However, in the conventional touch panel, since the film-like upper substrate 1 and the film-like lower substrate 4 are formed on the lower surface of the cover substrate 7 so as to overlap with each other, the overall thickness becomes thicker. The light transmittance was also about 87%, and there was a problem that the display of the menu of the display element on the back surface was difficult to see.

  The present invention solves such a conventional problem, and an object of the present invention is to provide a touch panel in which the display on the back display element is easy to see and easy to operate.

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

  According to the first aspect of the present invention, a plurality of upper conductive layers having a substantially strip shape are provided on the lower surface of the cover substrate via an adhesive layer, and a plurality of lower conductive layers having a substantially strip shape arranged in a direction orthogonal to the upper conductive layer. A layer is formed on the lower surface of the upper conductive layer via an adhesive layer to constitute a touch panel. The upper conductive layer is formed on the lower surface of the cover substrate via the adhesive layer without using a film-like upper substrate or lower substrate. By providing the lower conductive layer on the lower surface through an adhesive layer, the overall light transmittance can be increased, so that the display on the back of the touch panel is easy to see and the touch panel can be easily and reliably operated. It has the effect | action that can be obtained.

  According to a second aspect of the present invention, in the first aspect of the invention, an antireflective layer having a fine uneven portion formed on the lower surface is provided on the lower surface of the lower conductive layer. Therefore, the light transmittance of the touch panel can be further increased, making it easier to see and operate.

  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 that allows easy and reliable operation of the display on the back display element.

Sectional drawing of the touchscreen by one embodiment of this invention Exploded perspective view Partial sectional view of the same Partial sectional view of the same Partial sectional view of the same Exploded perspective view of a conventional touch panel

  Embodiments of the present invention will be described below with reference to FIGS.

  These drawings are partially enlarged in size for easy understanding of the configuration.

  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, FIG. 2 is an exploded perspective view thereof, in which 7 is a plate or film shape such as glass, polymethyl methacrylate, polycarbonate, etc. A light-transmitting cover substrate of about 0.3 to 2 mm, and a curable adhesive layer 11 having a thickness of about 10 to 50 μm, such as an ultraviolet curable acrylate type or a thermosetting epoxy type, is provided on the lower surface. ing.

  In addition, a plurality of upper conductive layers 12 that are light-transmitting and substantially band-shaped such as indium tin oxide and tin oxide are arranged on the lower surface of the cover substrate 7 with a curable adhesive layer 11 arranged in the left-right direction. Is connected to the end of the upper conductive layer 12 and the other end extends to the front end of the outer periphery, and a plurality of upper electrodes 13 in which a metal foil such as copper is stacked on the indium tin oxide or tin oxide by vapor deposition or the like. The conductive layer 12 is formed to extend in the front-rear direction in the orthogonal direction.

  A curable adhesive layer 11A is similarly laminated on the lower surface of the upper conductive layer 12, and a lower surface of the curable adhesive layer 11A has a plurality of light-transmitting substantially band-like lower layers such as indium tin oxide and tin oxide. A plurality of lower electrodes 16 in which a conductive layer 15 is arranged in the front-rear direction orthogonal to the upper conductive layer 12 and a metal foil such as copper is superimposed on indium tin oxide, tin oxide, or the like, has one end on the lower side. The conductive layer 15 is connected to the end of the conductive layer 15 and extends in the front-rear direction parallel to the lower conductive layer 15 so that the other end extends to the front end of the outer periphery.

  The plurality of upper conductive layers 12 and the lower conductive layer 15 are formed by connecting a plurality of square portions in a strip shape, and a plurality of substantially square gap portions are provided between them. In a state where the layer 12 and the lower conductive layer 15 are opposed to each other with a predetermined gap through the curable adhesive layer 11A, the respective rectangular portions are formed so as to alternately overlap the upper and lower spaces.

  Further, reference numeral 17 denotes an antireflective layer such as acrylic, cycloolefin, and polycarbonate. On the lower surface, fine irregularities are formed at a height and interval of about 100 to 350 nm, and the nonreflective layer 17 is formed on the lower surface of the lower conductive layer 15. The touch panel is formed.

  The touch panel configured as described above is disposed on the front surface of a display element such as a liquid crystal display element and attached to an electronic device, and a plurality of upper electrodes 13 and lower electrodes 16 extending to the outer peripheral right end are flexible wirings. It is electrically connected to an electronic circuit (not shown) of the device via a board, a connector (not shown) or the like.

  In the above-described configuration, with a voltage sequentially applied from the electronic circuit to the plurality of upper electrodes 13 and lower electrodes 16, a finger or the like is brought close to the upper surface of the cover substrate 7 according to the display on the display element on the back of the touch panel, or the cover is covered. When an operation is performed by touching the upper surface of the substrate 7, the capacitance between the upper conductive layer 12 and the lower conductive layer 15 at the operated position changes, so that the operated circuit is detected by the electronic circuit, and various devices are used. Function switching is performed.

  That is, for example, when a plurality of menus and the like are displayed on the display element on the back, when a finger or the like is brought close to or touches the upper surface of the cover substrate 7 on the desired menu, a part of the electric charge is conducted to the fingers, The capacitance between the upper conductive layer 12 and the lower conductive layer 15 of the touch panel at the operated location is changed, and the electronic circuit detects this, whereby a desired menu can be selected.

  In order to manufacture such a touch panel, as shown in the partial cross-sectional view of FIG. 3A, first, a polyethylene foil such as polyethylene terephthalate in which a copper foil 13A is laminated on a thin film 12A of indium tin oxide on the entire upper surface. After exposing and developing the upper surface of the copper foil 13A of the film-like substrate 20 by a photoresist method or the like and masking the pattern of the upper electrode 13 with a coating made of an insulating resin such as a dry film, the upper electrode 13 is It is immersed in an etching solution, and unnecessary portions of the copper foil 13A are melted and removed.

  Then, after a film covering the pattern of the upper conductive layer 12 is formed on the upper surface of the indium tin oxide thin film 12A by a photoresist method or the like, it is immersed in an etching solution different from the above, and the thin film 12A at an unnecessary portion is formed. As shown in FIG. 3 (b) by melting and removing, a plurality of upper conductive layers 12 having a substantially band shape on the upper surface of the base material 20, one end is connected to these end portions, and the other end extends to the outer peripheral front end. A plurality of upper electrodes 13 in which a copper foil is stacked on indium tin oxide are formed.

  Further, after that, a curable adhesive layer 11 is affixed to the entire upper surface of the base material 20 so as to cover the plurality of upper conductive layers 12 and the upper electrodes 13, and a plurality of surfaces on the upper surface as shown in FIG. The base material 20 on which the upper conductive layer 12, the plurality of upper electrodes 13, and the curable adhesive layer 11 are formed is produced.

  Similarly, as shown in the partial cross-sectional view of FIG. 4A, etching is performed on the base material 20A in which the copper foil 16A is laminated on the thin film 15A of indium tin oxide on the entire upper surface, and FIG. As shown in FIG. 4B, after a plurality of lower conductive layers 15 and lower electrodes 16 are formed on the upper surface of the substrate 20A, a curable adhesive layer 11A is pasted on the entire upper surface, as shown in FIG. The base material 20A having a plurality of lower conductive layers 15, lower electrodes 16, and curable adhesive layers 11A formed on the upper surface is prepared.

  Further, after the base material 20 on which the upper conductive layer 12 and the upper electrode 13 are formed is bonded to the lower surface of the cover substrate 7 with the curable adhesive layer 11 as shown in the partial cross-sectional view of FIG. The curable adhesive layer 11 is cured by irradiating it with ultraviolet rays or heating and pressing.

  Next, as shown in FIG. 5B, after the base material 20 is peeled off and the upper conductive layer 12 and the upper electrode 13 are transferred to the lower surface of the curable adhesive layer 11, the lower surface of FIG. As shown, the base material 20A on which the lower conductive layer 15 and the lower electrode 16 are formed is bonded together by the curable adhesive layer 11A, and similarly, the curable adhesive layer 11A is cured by irradiating with ultraviolet rays or heating and pressing. .

  Then, as shown in FIG. 5D, the base material 20A is peeled off, the lower conductive layer 15 and the lower electrode 16 are transferred to the lower surface of the curable adhesive layer 11A, and the curable adhesive layer 11 is applied to the lower surface of the cover substrate 7. Thus, the upper conductive layer 12 and the upper electrode 13 are formed, and a touch panel in which the lower conductive layer 15 and the lower electrode 16 are provided on the lower surface of the upper conductive layer 12 via the curable adhesive layer 11A is completed.

  Moreover, a touch panel as shown in FIG. 1 is manufactured by sticking a sheet or the like on the lower surface and providing the non-reflective layer 17 having fine irregularities formed on the lower surface of the lower conductive layer 15.

  In other words, in the present invention, a plurality of upper conductive layers 12 having a substantially band shape are provided on the lower surface of the cover substrate 7 via the curable adhesive layer 11, and a plurality of strips having a substantially band shape arranged in a direction orthogonal to the upper conductive layer 12. By forming the lower conductive layer 15 on the lower surface of the upper conductive layer 12 through the curable adhesive layer 11A, a touch panel having a high light transmittance is obtained.

  That is, as described in the background art section, a thin curable adhesive layer 11 having a thickness of about 10 to 50 μm is used without using the upper substrate 1 and the lower substrate 4 having a thickness of about 50 to 125 μm. By forming the upper conductive layer 12 on the lower surface of the cover substrate 7 and the lower conductive layer 15 on the lower surface of the upper conductive layer 12 via 11A, the light transmittance can be increased to about 91%. Therefore, the display of the display element on the back of the touch panel is easy to see, and an easy and reliable operation can be performed.

  Further, by providing the non-reflective layer 17 having a fine uneven portion on the lower surface on the lower surface of the lower conductive layer 15, the non-reflective layer 17 can prevent reflection of external light or the like. It can be further increased.

  That is, by providing the lower surface of the lower conductive layer 15 with the non-reflective layer 17 on the lower surface of which concave and convex portions having a height and interval of about 100 to 350 nm, which are much smaller than the wavelength of light of about 400 to 750 nm, are formed. Since the non-reflective layer 17 prevents reflection of external light and the like, and the light transmittance can be increased to about 96%, the touch panel can be more easily seen and operated.

  The plurality of upper electrodes 13 and lower electrodes 16 may be formed on the upper surface of the base material 20 or 20A by printing using silver, carbon or the like, and transferred to the lower surface of the curable adhesive layer 11 or 11A. Although it is possible to implement the present invention, the upper electrode 13 and the lower electrode are made of metal foil such as copper by overlapping the metal foil such as copper on the indium tin oxide or tin oxide as described above. The upper electrode 13 is designed to be thinned or narrowed, with a low and stable resistance value without blurring or blurring of the electrode 16 and with a line width and line spacing of around 0.03 to 0.05 mm. The lower electrode 16 can also be formed.

  In the above description, the structure in which the upper conductive layer 12 and the lower conductive layer 15 are formed of indium tin oxide, tin oxide, or the like has been described. However, a conductive polymer such as polythiophene or a nanotube such as carbon or silver is dispersed. The present invention can be carried out even when the substantially band-shaped upper conductive layer 12 and lower conductive layer 15 are formed of the light-transmitting resin.

  As described above, according to the present embodiment, a plurality of upper conductive layers 12 having a substantially strip shape are provided on the lower surface of the cover substrate 7 via the curable adhesive layer 11 and are arranged in a direction orthogonal to the upper conductive layer 12. By forming the plurality of lower conductive layers 15 on the lower surface of the upper conductive layer 12 via the curable adhesive layer 11A, the curable adhesive layer 11 is formed on the lower surface of the cover substrate 7 without using a film-like upper substrate or lower substrate. By providing the upper conductive layer 12 and the lower conductive layer 15 via 11A, the overall light transmittance can be increased, so that the display on the back of the touch panel is easy to see, easy and reliable operation The touch panel which can do is obtained.

  In addition, since the non-reflective layer 17 having a fine uneven portion formed on the lower surface is provided on the lower surface of the lower conductive layer 15, the non-reflective layer 17 can prevent reflection of external light and the like. Can be further increased to make it easier to see and operate.

  The touch panel according to the present invention has an advantageous effect that it is easy to see the display of the display element on the back surface and can be easily and surely operated, and is mainly useful for operation of various electronic devices.

7 Cover substrate 11, 11A Curing adhesive layer 12 Upper conductive layer 12A Thin film 13 Upper electrode 13A Copper foil 15 Lower conductive layer 15A Thin film 16 Lower electrode 16A Copper foil 17 Non-reflective layer 20, 20A Base material

Claims (2)

A plurality of upper conductive layers in a substantially strip shape arranged in a predetermined direction, and a plurality of lower conductive layers in a substantially strip shape arranged in a perpendicular direction with a predetermined gap from the upper conductive layer, covering the upper conductive layer A touch panel in which the lower conductive layer is provided on the lower surface of the substrate via the adhesive layer, and the lower conductive layer is formed on the lower surface of the upper conductive layer via the adhesive layer. The touch panel according to claim 1, wherein a non-reflective layer having a fine uneven portion formed on the lower surface is provided on the lower surface of the lower conductive layer.

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