JP2014071865A - Touch panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a touch panel having good appearance.SOLUTION: An electrostatic capacitive touch panel 1 includes a transparent base material 10, a first detection electrode pattern 20 provided on a first principal surface 10a of the transparent base material 10, a transparent insulating layer 40 provided on the first principal surface 10a to cover the first detection electrode pattern 20, and a second detection electrode pattern 50 provided on the transparent insulating layer 40.

Description

  The present invention relates to a capacitive touch panel.

  A touch panel having a structure in which two types of electrode patterns orthogonal to each other are formed on the same substrate, and a conductive line connecting electrodes of one electrode pattern straddles a conductive line connecting electrodes of the other electrode pattern Is known (see, for example, Patent Document 1).

JP 2011-22659 A

  In the above structure, since the transmittance of the portion where the conductive lines overlap is different from the transmittance of the other portions, there is a problem that the transmittance of the entire touch panel varies and the appearance may be inferior.

  The problem to be solved by the present invention is to provide a touch panel having a good appearance.

  [1] A touch panel according to the present invention is a capacitive touch panel, and includes a transparent base material, a first detection electrode pattern provided on a first main surface of the transparent base material, and the first touch panel. A transparent insulating layer provided on the first main surface so as to cover one detection electrode pattern, and a second detection electrode pattern provided on the transparent insulating layer. .

  [2] In the above invention, the touch panel is provided on the first main surface, and is provided on the first main surface and a first lead wiring pattern connected to the first detection electrode pattern. The second lead wiring pattern, and a third lead wiring pattern provided on the transparent insulating layer and connected to the second detection electrode pattern, the third lead wiring pattern comprising: The second lead wiring pattern may be connected.

  [3] In the above invention, the transparent insulating layer covers the first lead wiring pattern and the second lead wiring pattern, and the third lead wiring pattern is formed on the transparent insulating layer. It may be connected to the second lead wiring pattern through an opening.

  [4] In the above invention, the transparent substrate surrounds the first region where the first detection electrode pattern is provided, the first region, the first lead wiring pattern and the second region. A second region provided with a lead wiring pattern, and the opening may be disposed on the second region of the transparent substrate.

  [5] In the above invention, the transparent base material has a third region that protrudes outward from the second region, and the first lead-out wiring pattern and the second lead-out wiring pattern are It may extend to the third region.

  [6] In the above invention, a plurality of the openings are formed in the transparent insulating layer, and one of the third lead wiring patterns is connected to one second lead wiring pattern through the one opening. It may be connected to.

  In the present invention, since the first detection electrode pattern is provided on the first main surface of the transparent substrate and the second detection electrode pattern is provided on the insulating layer provided on the first main surface, The variation in transmittance is reduced, and the appearance of the touch panel is improved.

FIG. 1 is a plan view of a touch panel according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is a plan view showing a transparent substrate in the embodiment of the present invention. FIG. 4 is a plan view showing a state where the first detection electrode pattern is formed on the transparent substrate of FIG. FIG. 5 is a plan view showing a state where the first and second lead wiring patterns are formed on the transparent substrate of FIG. FIG. 6 is a plan view showing a state in which a protective layer is formed at the ends of the first and second lead wiring patterns in FIG. FIG. 7 is a plan view showing a state in which a transparent insulating layer is formed on the transparent substrate of FIG. FIG. 8 is a plan view showing a state where the second detection electrode pattern is formed on the transparent insulating layer of FIG. FIG. 9 is a plan view showing a state in which a third lead wiring pattern is formed on the transparent insulating layer of FIG. FIG. 10 is a plan view showing a cover panel in the embodiment of the present invention. FIG. 11 is a cross-sectional view showing a modification of the touch panel in the embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 is a plan view of a touch panel according to the present embodiment, FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1, and FIGS. 3 to 10 are exploded plan views of the touch panel according to the present embodiment. 2 is a cross-sectional view taken along the second detection electrode pattern 50, the third lead wiring pattern 61, the opening 41, and the second lead wiring pattern 32 located at the top of FIG. .

  The touch panel 1 in the present embodiment is, for example, a mutual capacitance type capacitive sensor (touch sensor, input device), and as illustrated in FIGS. 1 and 2, a transparent base material 10 and a first detection electrode pattern 20. The first and second lead wiring patterns 31, 32, the transparent insulating layer 40, the second detection electrode pattern 50, the third lead wiring pattern 61, the transparent adhesive layer 70, the cover panel 80, It is equipped with.

  The transparent substrate 10 is a substrate that can transmit visible light and has flexibility. Specific examples of the material constituting the transparent substrate 10 include, for example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethylene (PE), polypropylene (PP), polystyrene (PS), and ethylene-vinyl acetate copolymer. Examples of the resin material include resin (EVA), vinyl resin, polycarbonate (PC), polyamide (PA), polyimide (PI), polyvinyl alcohol (PVA), acrylic resin, and triacetyl cellulose (TAC).

  The transparent substrate 10 may be a rigid substrate as long as it can transmit visible light. In this case, the transparent substrate 10 may be made of glass or the like in addition to the resin material described above. Good.

  As shown in FIGS. 2 and 5, the first detection electrode pattern 20 and the first and second lead wiring patterns 31 and 32 are formed on the surface 10 a of the transparent substrate 10. In the present embodiment, three regions 11 to 13 as shown in FIG. 3 are set on the surface 10 a of the transparent substrate 10.

  Specifically, the first area 11 has a rectangular shape, the second area 12 has a rectangular frame shape surrounding the first area 11, and the third area 13 is a second area. 12 has a rectangular shape protruding outward. In addition, the surface 10a of the transparent base material 10 in this embodiment is equivalent to an example of the 1st main surface of the transparent base material in this invention.

  And the 1st detection electrode pattern 20 is provided in the 1st area | region 11 of the transparent base material 10, as shown in FIG. The first detection electrode pattern 20 is a transparent electrode made of, for example, indium tin oxide (ITO) or a conductive polymer.

  In the present embodiment, the first detection electrode pattern 20 is composed of five strip-shaped solid patterns (planar patterns) extending in the Y direction in the drawing, and the first region 11 is illustrated in FIG. Dividing substantially evenly along the middle X direction. The shape, number, layout, etc. of the first detection electrode pattern 20 are not particularly limited to the above.

  When the first detection electrode pattern 20 is made of ITO, it is formed by sputtering, photolithography, and etching, for example. On the other hand, when the first detection electrode pattern 20 is composed of a conductive polymer, instead of sputtering similar to the case of ITO, a printing method such as screen printing or gravure offset printing, or etching after coating is performed. It can also be formed by performing.

  Specific examples of the conductive polymer constituting the first detection electrode pattern 20 include organic compounds such as polythiophene, polypyrrole, polyaniline, polyacetylene, and polyphenylene, among these. It is preferable to use a PEDOT / PSS compound.

  On the other hand, the first and second lead wiring patterns 31 and 32 are provided in the second region 12 and the third region 13 of the transparent substrate 10 as shown in FIG. The first lead wiring patterns 31 and 32 are formed, for example, by printing a conductive paste on the transparent base material 10 and curing it. Examples of such a conductive paste include silver (Ag) and A mixture of metal particles such as copper (Cu) and a binder such as polyester or polyphenol can be used.

  In the present embodiment, as shown in FIG. 5, five first lead wiring patterns 31 are formed on the transparent substrate 10. The five first lead wiring patterns 31 correspond to the five first detection electrode patterns 20, respectively. Each first lead-out wiring pattern 31 is connected to the first detection electrode pattern 20 at one end thereof, and is extended to the third region 13 along the outer edge of the second region 12. The other end 311 of one lead wiring pattern 31 is located in the vicinity of the end of the third region 13.

  On the other hand, the second lead wiring pattern 32 is extended from the right end portion in the drawing in the second region 12 to the third region 13, and the end portion 321 of the second lead wiring pattern 32. Is located near the end of the third region 13. The second lead wiring pattern 32 is a wiring pattern for electrically connecting a third lead wiring pattern 61 described later to the connector.

  Note that the first detection electrode pattern 20 described above may be formed by printing and curing a conductive paste on the transparent substrate 10 in the same manner as the first and second lead wiring patterns 31 and 32. Good. In this case, each first detection electrode pattern 20 is formed in a mesh shape in order to ensure sufficient light transmission. The line width of the mesh pattern is 1 μm to 20 μm, preferably 5 μm to 10 μm, and the thickness of the mesh pattern is 0.1 μm to 20 μm, preferably 1 to 5 μm.

  Furthermore, when all the patterns 20, 31, 32 are formed of conductive paste having the same composition, these patterns 20, 31, 32 can be printed at the same time, and the number of processes can be reduced.

  As shown in FIGS. 2 and 6, the end portions 311 and 321 of the first and second lead-out wiring patterns 31 and 32 located on the third region 13 are electrically conductive because connectors not shown are particularly fitted. It is covered with a protective layer 35 having a property. The conductive protective layer 35 is formed, for example, by printing and curing a carbon paste on the end portions 311 and 321 of the first and second lead wiring patterns 31 and 32.

  In addition, the connector fitted to the first and second lead wiring patterns 31 and 32 is connected to a touch panel drive circuit (not shown). For example, the touch panel drive circuit periodically applies a predetermined voltage between the first detection electrode pattern 20 and a second detection electrode pattern 50 to be described later, so that the first and second detection electrode patterns 20 and 50 are applied. The contact position of the finger on the touch panel 1 is determined based on the change in capacitance at each intersection.

  Incidentally, the portions corresponding to the first and second regions 11 and 12 in the touch panel 1 of the present embodiment constitute a sensor unit 1 a that detects a change in capacitance, and the third region 13 in the touch panel 1. The part corresponding to 1 constitutes a wiring extraction part 1b (so-called tail part) for extracting the wiring from the sensor part 1a (see FIG. 1). And this wiring extraction part 1b is bend | folded in the state connected to the connector, when the touch panel 1 is integrated in the housing of electronic devices, such as a mobile telephone, for example.

  As shown in FIGS. 2 and 7, the transparent insulating layer 40 is a resin layer capable of transmitting visible light and having flexibility, and on the first to third regions 11 to 13 of the transparent substrate 10. The first detection electrode pattern 20 and the first and second lead wiring patterns 31 and 32 are covered. As shown in FIG. 7, the protective layer 35 is exposed from the end of the transparent insulating layer 40.

  The transparent insulating layer 40 is formed, for example, by printing and curing a resin material on the transparent base material 10, and examples of the resin material constituting the transparent resin layer 40 include polyester, polyacryl, A resin material having electrical insulation such as polyurethane can be exemplified. The layer thickness of the transparent insulating layer 40 is, for example, 5 μm to 50 μm, preferably 35 μm to 45 μm.

  In the present embodiment, as shown in FIG. 7, three openings 41 to 43 are formed at the right end portion in the drawing in the second region 12. As will be described later, these openings 41 to 43 electrically connect the third lead wiring pattern 61 formed on the transparent insulating layer 40 and the second lead wiring pattern 32 formed on the transparent substrate 10. Is a through hole for electrical conduction.

  In the present embodiment, one opening 41 to 43 is assigned to each of the three combinations of the second and third lead wiring patterns 32 and 61 connected to each other. Accordingly, it is possible to prevent the third leading wiring pattern 61 from bleeding due to the step at the peripheral edge of the opening, and the adjacent third leading wiring patterns 61 from being short-circuited.

  In the present embodiment, since the openings 41 to 43 are arranged on the second area 12, the openings 41 to 43 are hidden by a concealing portion 81 (so-called frame area) of the cover panel 80 described later, and the touch panel 1. It is possible to prevent a decrease in visibility.

  On the transparent insulating layer 40, as shown in FIGS. 2 and 9, a second detection electrode pattern 50 and a third lead wiring pattern 61 are formed.

  As shown in FIG. 8, the second detection electrode pattern 50 is provided in a portion corresponding to the first region 11 in the transparent insulating layer 40. The second detection electrode pattern 50 is a transparent electrode made of, for example, indium tin oxide (ITO) or a conductive polymer, like the first detection electrode pattern described above.

  In the present embodiment, the second detection electrode pattern 50 is composed of three strip-shaped solid patterns extending in the X direction in the drawing, and the first region 11 extends along the X direction in the drawing. The first detection electrode pattern 20 is substantially orthogonal to the first detection electrode pattern 20 in plan view. The shape, number, layout, etc. of the second detection electrode pattern 50 are not particularly limited to the above.

  On the other hand, as shown in FIG. 9, the third lead wiring pattern 61 is provided between the second detection electrode pattern 50 and the openings 41 to 43 on the transparent insulating layer 40. The second lead wiring pattern 32 is connected to the transparent substrate 10 via 43.

  The third lead wiring pattern 61 is formed by printing and curing a conductive paste on the transparent insulating layer 40 in the same manner as the first and second lead wiring patterns 31 and 32 described above. As such an electrically conductive paste, what mixed metal particles, such as silver (Ag) and copper (Cu), and binders, such as polyester and polyphenol, can be used, for example.

  Note that the second detection electrode pattern 50 described above may be formed by printing and curing a conductive paste on the transparent substrate 10 in the same manner as the third lead wiring pattern 61. In this case, each second detection electrode pattern 50 is formed in a mesh shape in order to ensure sufficient light transmission. The line width of the mesh pattern is 1 μm to 20 μm, preferably 5 μm to 10 μm, and the thickness of the mesh pattern is 0.1 μm to 20 μm, preferably 1 to 5 μm.

  Furthermore, when all the patterns 50 and 61 are formed of the conductive paste having the same composition, these patterns 50 and 61 can be printed at the same time, and the number of processes can be reduced.

  As shown in FIG. 2, the cover panel 80 is a transparent substrate attached to the transparent base material 10 via the transparent adhesive layer 70, and can transmit visible light. Specific examples of the material constituting the cover panel 80 include glass, polymethyl methacrylate (PMMA), polycarbonate (PC), and the like.

  As shown in FIGS. 2 and 10, a shielding portion 81 formed by applying, for example, black ink is provided on the back surface of the cover panel 80. The shielding portion 81 is formed on the back surface of the cover panel 80 except for the central rectangular region 82.

  The cover panel 80 is affixed to the transparent base material 10 via the transparent adhesive layer 70 so that the rectangular region 82 faces the first and second detection electrode patterns 20 and 50, and the frame shape described above. The first to third wiring patterns 31, 32, 61 are concealed by the shielding portion 81. Note that. As a specific example of the transparent adhesive layer 70, an acrylic adhesive can be illustrated, for example. The layer thickness of the transparent adhesive layer 70 is, for example, 50 μm to 500 μm, and preferably 100 μm to 200 μm.

  As described above, in the present embodiment, the first detection electrode pattern 20 is provided on the surface 10a of the transparent substrate 10, and the second detection electrode pattern is provided on the transparent insulating layer 40 provided on the surface 10a. 50 is provided, variation in transmittance is reduced, and the appearance of the touch panel 1 is improved.

  In the present embodiment, since the third lead wiring pattern 61 is connected to the second lead wiring pattern 32 through the openings 41 to 43 of the transparent insulating layer 40, the detection electrode patterns 20 and 50 are arranged on the same surface. 10a can be connected to the outside, facilitating connection work and improving connection reliability.

  The embodiment described above is described for facilitating the understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

  For example, in the above-described embodiment, the first detection electrode pattern 20, the first and second lead wiring patterns 31 and 32, the transparent insulating layer 40, the second detection electrode pattern 50, and the first detection electrode pattern 20 are formed on the transparent substrate 10. However, the present invention is not limited to this. As shown in FIG. 11, the transparent substrate 10 is omitted, and the first detection electrode pattern 20 and the first detection electrode pattern 20 are formed on the cover panel 80. The first and second lead wiring patterns 31, 32, the transparent insulating layer 40, the second detection electrode pattern 50, and the third lead wiring pattern 61 may be laminated. FIG. 11 is a cross-sectional view showing a modification of the touch panel in the present embodiment.

  Specifically, as shown in the figure, first, the first detection electrode pattern 20 is formed in the rectangular region 82 of the cover panel 80, and the first and second lead wiring patterns 31, 32 is formed, and a first transparent insulating layer 40 is formed thereunder. Further, a second detection electrode pattern 50 and a third lead wiring pattern 61 are formed under the first transparent insulating layer 40, and a second transparent insulating layer 90 is formed thereunder.

  The third lead wiring pattern 61 is connected to the second lead wiring pattern through the opening 41 formed in the first transparent insulating layer 40. In addition, the second transparent insulating layer 90 is made of an electrically insulating resin material such as polyester, polyacryl, polyurethane, etc., like the transparent insulating layer 40 described above.

  In the case of the example shown in FIG. 11, the cover panel 80 corresponds to an example of the transparent substrate in the present invention.

  In the above-described embodiment, an example in which the present invention is applied to a mutual capacitive touch panel has been described. However, the present invention is not particularly limited thereto, and the present invention may be applied to a self-capacitive touch panel.

  In this case, although not particularly illustrated, for example, the first detection electrode pattern has a plurality of rhombus shapes connected in the Y direction, and the second detection electrode pattern is also a plurality of rhombus shapes connected in the X direction. These rhombus shapes are alternately arranged so as not to overlap each other.

  In the above-described embodiment, the third lead wiring pattern 61 is connected to the second lead wiring pattern 32 through the openings 41 to 43 formed in the transparent insulating layer 40. However, the present invention is not particularly limited to this. For example, the end portion of the second lead wiring pattern 32 is not exposed from the transparent insulating layer 40, or the transparent insulating layer 40 is not formed on most of the second lead wiring pattern 32, and the exposed portion thereof Three lead wiring patterns 61 may be connected to the second lead wiring pattern 32.

DESCRIPTION OF SYMBOLS 1 ... Touch panel 1a ... Sensor part 1b ... Wiring extraction part 10 ... Transparent base material 10a ... Surface 11 ... 1st area | region 12 ... 2nd area | region 13 ... 3rd area | region 20 ... 1st detection electrode pattern 31 ... 1st Lead wiring pattern 311 ... End 32 ... Second lead wiring pattern 321 ... End 35 ... Protective layer 40 ... Transparent insulating layer 41-43 ... Small opening 50 ... Second detection electrode pattern 61 ... Third lead wiring Pattern 70 ... Transparent adhesive layer 80 ... Cover panel 81 ... Shielding part 82 ... Rectangular area 90 ... Second transparent insulating layer

Claims (6)

A capacitive touch panel,
A transparent substrate;
A first detection electrode pattern provided on the first main surface of the transparent substrate;
A transparent insulating layer provided on the first main surface so as to cover the first detection electrode pattern;
A touch panel comprising: a second detection electrode pattern provided on the transparent insulating layer. The touch panel according to claim 1,
A first lead wiring pattern provided on the first main surface and connected to the first detection electrode pattern;
The second lead wiring pattern provided on the first main surface;
A third lead wiring pattern provided on the transparent insulating layer and connected to the second detection electrode pattern,
The touch panel, wherein the third lead wiring pattern is connected to the second lead wiring pattern. The touch panel according to claim 2,
The transparent insulating layer covers the first lead wiring pattern and the second lead wiring pattern,
The touch panel, wherein the third lead wiring pattern is connected to the second lead wiring pattern through an opening formed in the transparent insulating layer. The touch panel according to claim 3,
The transparent substrate is
A first region provided with the first detection electrode pattern;
Surrounding the first region, and having a second region provided with the first lead wiring pattern and the second lead wiring pattern,
The touch panel, wherein the opening is disposed on the second region of the transparent substrate. The touch panel according to claim 4,
The transparent substrate has a third region protruding outward from the second region;
The touch panel, wherein the first lead wiring pattern and the second lead wiring pattern extend to the third region. The touch panel according to any one of claims 1 to 5,
A plurality of the openings are formed in the transparent insulating layer;
The touch panel, wherein one third lead wiring pattern is connected to one second lead wiring pattern through one opening.

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