JP5884763B2 - Electrode substrate for touch panel, touch panel, and image display device - Google Patents

Description

  The present invention relates to an electrode substrate for a touch panel, a touch panel using the same, and an image display device using the touch panel. In particular, the present invention relates to an electrode substrate for a touch panel and a touch panel in which slits (line defect portions) for separating the electrodes for the touch panel are hardly visible, and an image display device using the touch panel.

  In recent years, the use of a touch panel (also called a touch screen or a touch screen) in which a display device and a position input device are combined has been actively used. Various types of position input devices such as a matrix switch method, an electric resistance film method, a surface acoustic wave method, an infrared method, an electromagnetic induction method, and a capacitance method have been put into practical use. In particular, the touch panel combined with the projected capacitive position input device, which is one of the electrostatic capacity methods, is capable of multi-touch (multi-point simultaneous input), and can be operated intuitively with the fingertips. It has been widely used in mobile phones and mobile terminals due to its excellent performance.

  In a projected capacitive touch panel, a touch panel electrode substrate is required in which a plurality of sensor electrode patterns that are insulated and extended in the vertical and horizontal directions are arranged on a transparent insulating substrate such as glass or plastic.

  Furthermore, since the electrode substrate for touch panels is installed between the display device and the observer, transparency is required.

Patent Document 1 describes an electrode substrate for a touch panel using a transparent conductive film such as ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide) as a transparent sensor electrode. However, the transparent conductive film made of an ITO thin film is expensive because a rare metal called indium is used, and the electrical resistance (surface electrical resistivity) is high in order to increase the area of the touch panel. Therefore, if the film thickness is increased to reduce the electrical resistance to an appropriate range, the transparency is lowered, and it is difficult to satisfy both the transparency and the appropriate electrical resistance.

  Therefore, in place of a transparent conductive film such as an ITO thin film, a sensor in which a mesh sensor electrode formed in a mesh shape composed of a linear pattern of a conductor of low electrical resistance such as copper is formed on a transparent insulating substrate has been proposed. (Patent Document 2). According to the mesh-shaped sensor electrode composed of a metal wire portion having a low electrical resistance, the electrical resistance can be reduced at a lower cost than the ITO thin film.

JP 2008-310551 A JP 2006-344163 A

  However, as shown in FIGS. 5 and 6, the conventional mesh electrode pattern is an electrode that realizes transparency by forming a low resistance conductive metal into a mesh pattern as a conductor line portion 2. In the touch panel electrode substrate 1 in which E is provided on one or both surfaces of the transparent insulating substrate 3, the line defect portions (g1, g2, g3,..., Gi) for separating the electrodes are substantially in a straight line. Therefore, the line defect separation line G formed by connecting these line defect parts (g1, g2, g3,..., Gi) becomes a straight line, and the line defect defect separation line between the electrodes becomes a whitish stripe-like unevenness visually. The presence of G is recognized, which causes an appearance problem.

  The present invention has been made in view of such a situation, and as a projected capacitive touch panel, a striped unevenness caused by the line defect separation line G of the electrode substrate for touch panel 1 is difficult to be visually observed. It is an object to realize an electrode substrate 1 for use, a touch panel using the same, and an image display device using the touch panel.

In view of the above situation, earnest research and development has been proceeded, and claim 1 of the present invention is composed of a plurality of conductor line portions 2 formed of a conductor on at least one surface of transparent insulating substrate 1. in the electrode E of the plurality of mesh shape, streak defect of the conductive linear portions 2 provided for providing electrical isolation between adjacent said electrodes (E1, E2) (g1, g2, g3, .., Gi) are linear defect separation lines G that are non-linear, and the width Ag of each defect portion is equal to or less than the period T of the mesh shape forming the electrode. It is.

  In addition, claim 2 of the present invention is a touch panel using the electrode substrate for touch panel according to claim 1.

  In addition, a third aspect of the present invention is an image display device using the touch panel according to the second aspect.

  According to the present invention, a low-cost metal electrode can be used as a projection-type capacitive touch panel electrode, and transparency can be ensured, and stripe-like unevenness caused by a line defect separation line G between the electrodes can be secured. An electrode substrate for a touch panel that is difficult to see can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram (perspective view) which shows a part of electrode substrate for touch panels of the 1st form which is one Embodiment of this invention. It is the schematic diagram which planarly viewed the electrode substrate for touch panels of the 1st form which is one Embodiment of this invention. This drawing is an enlarged plan view of a portion J surrounded by a thick dotted line in FIG. 1 which is a perspective view. It is a schematic diagram (perspective view) which shows a part of the electrode substrate for touch panels of the 2nd form which is one Embodiment of this invention. It is the schematic diagram which planarly viewed the electrode substrate for touch panels of the 2nd form which is one Embodiment of this invention. This drawing is a plan view enlarged view of a portion K surrounded by a thick dotted line in FIG. 3 which is a perspective view. It is the 1st reference example of the conventional electrode substrate for touch panels, and is the mimetic diagram showing the state of the line defect separation line by plane view. It is the 2nd reference example of the conventional electrode substrate for touch panels, and is a mimetic diagram showing the state of the line defect separation line by plane view. This is an application example of the present invention. (A) is a top view of the electrode substrate for deformable touch panels, and the dotted line indicates that it is on the back side of the transparent substrate. (B) is the electrode which looked at the site | part of L of (a) from the back surface, and the right side of the enlarged view (b) of the part M has shown that this invention is applied.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the following embodiments, and can be implemented with appropriate modifications within the scope of the object of the present invention. Note that the drawings are conceptual diagrams, and the scale relations, aspect ratios, and the like of components may be exaggerated as appropriate for convenience of explanation. In addition, in this specification, a part of electrodes of the electrode substrate for a touch panel, which is a main part of the present invention, is described and illustrated. In an actual product, in addition to this, a dummy electrode, a terminal electrode unit, and a sensor In many cases, a wiring portion or the like for electrically connecting the electrode and the terminal electrode portion is provided as necessary.

  “Sheet surface” means that when the sheet-like electrode substrate for touch panel 1 is viewed as a whole and globally, it coincides with the planar direction. The “sheet surface” is also usually the surface of the transparent insulating substrate 3 or a parallel surface, and in FIG. 1 is the XY plane or a surface parallel thereto.

  “Plan view” means viewing from the direction of the normal line set up on the “sheet surface”. The “planar shape” means a shape in a plane parallel to the “sheet surface”. In other words, the “planar shape” means a shape viewed from the direction of the normal line set on the “sheet surface”.

  The terms “sheet”, “film”, and “plate” are not distinguished from each other based solely on the difference in designation. Therefore, for example, “plate” is a concept including a member that can also be called a film or a sheet.

[Electrode substrate for touch panel]
As illustrated in FIGS. 2 and 3, the touch panel electrode substrate 1 according to the present invention includes a plurality of electrodes E <b> 1, E <b> 2, E <b> 3, etc. made of a conductor on at least one surface (surface) of the sheet surface of the transparent insulating substrate 3. Thus, the electrode E1, the electrode E2, and the electrode E3 are electrically insulated and formed independently. Although not shown, an electrode extending in a direction intersecting the front surface is formed on the back surface.

  For convenience of explanation, the side that becomes the front surface when the plan view of FIG. 2 or FIG. 4 is referred to as the front surface, and the other surface of the transparent insulating substrate 3 on the back surface side is referred to as the back surface. These are names for distinguishing the electrodes when the electrodes are formed on both surfaces of the touch panel electrode substrate 1 for the sake of explanation. Basically, one surface may be either the front surface or the back surface when viewed in plan. It is not named for the purpose of limiting to the surface. The same applies to the other surface.

In order to function as the electrode substrate 1 for a normal touch panel, a plurality of sensor electrodes (Ex, Ey) extending in at least two intersecting directions are required as shown in FIG. Yes, a dummy electrode Ed is provided for the purpose of aligning the visible light reflectance and visible light transmittance of the sensor electrode (Ex, Ey) forming portion and the non-forming portion as required.

  Which electrode is adjacent is different depending on the arrangement of the sensor electrode (Ex, Ey) and the dummy electrode (Ed). Therefore, in the explanatory diagrams of FIGS. 1 to 4, the electrodes provided on the same surface are referred to as electrodes E <b> 1, E <b> 2, and E <b> 3 without distinction between sensor electrodes and dummy electrodes.

  Although not shown in the present application, other dummy electrodes exemplified for ensuring uniformity in processing steps and visual uniformity as necessary, terminal electrode portions connected to other components at the time of mounting, In many cases, a wiring portion for electrically connecting the sensor electrode and the terminal electrode portion is provided as necessary. These are appropriately formed according to the manufacturing process and product specifications.

  In addition, for the purpose of protecting the sensor electrode 2, an electrode can be formed, and a film can be attached or a hard coat layer can be formed.

[Transparent insulating substrate]
The transparent insulating substrate 3 is not particularly limited as long as it is a transparent and electrically insulating substrate that generally transmits visible wavelengths (360 nm to 830 nm), and is a polyester resin such as polyethylene terephthalate or polyethylene naphthalate. An acrylic resin such as polymethyl methacrylate, a polyolefin resin such as polypropylene, a cellulose resin such as triacetylcellulose (cellulose triacetate), a resin sheet made of polycarbonate resin, an inorganic plate made of glass, ceramics, or the like can be used. .

  The thickness of the transparent insulating substrate 3 is preferably 5 to 350 μm, and more preferably 30 to 150 μm. If it is the range of 5-350 micrometers, the transmittance | permeability of a desired visible light will be obtained and handling will also be easy.

In general, when the electrode substrate for touch panel 1 or a touch panel using the same is disposed on the display surface of the liquid crystal display device, when a normal biaxially stretched polyethylene terephthalate sheet is used as the transparent insulating substrate 3, the sheet The rotation effect of the polarization plane of the outgoing light of the liquid crystal display device due to the optical anisotropy and the polarizing filter effect of the sheet (the P-polarized component increases in the transmitted light and the S-polarized component increases in the reflected light) It is known that interference fringes or rainbow-colored irregularities are visually recognized and the image visibility is hindered by the combined effect (see Japanese Patent No. 3947950, Japanese Patent No. 4888853, etc.). Such a problem can also occur in the touch panel electrode substrate 1 of the present invention or a touch panel using the same. In order to eliminate such interference fringes or iridescent unevenness, it is effective to use one of the following as the transparent insulating substrate 3.
(1) A material having a small refractive index anisotropy such as a triacetylcellulose sheet.
(2) As disclosed in Japanese Patent No. 3947950, Japanese Patent No. 4888853 and the like, the in-plane retardation value Re is sufficiently larger than that of a normal biaxially stretched polyethylene terephthalate sheet, specifically, Re A polyester resin sheet such as a polyethylene terephthalate sheet stretched at a high stretch ratio (about 3 to 7 times) of ≧ 3000 nm, more preferably Re ≧ 8000 nm. Here, the in-plane retardation value Re is defined as Re = (nx−ny) × d from the phase axis direction refractive index nx, phase advance axis direction refractive index ny, and thickness d in the sheet surface of the resin sheet. Be done

  In the present invention, the electrode is formed of a plurality of mesh conductors as shown in FIGS. 1 to 4 and 7. The mesh-like electrode is formed including at least a conductor line portion 2 formed of a conductive material and an electrode opening 5 which is a non-formation portion of the conductive material surrounded by the conductor line portion 2. Electrode. Usually, the ratio of the area of the non-formation portion of the conductive material is larger than the area of the formation portion of the conductive material.

  The electrode E is composed of a conductor wire portion 2. As shown in FIGS. 2 and 4, which are enlarged views of the electrode portion, the electrode is composed of a conductor line portion 2 made of parallel lines of different directions made of a conductive material and an electrode opening portion 5. Considering the electrode opening 5 as a center, it can be said that the electrode opening 5 is surrounded and formed by the conductor wire portion 2 formed of a conductor material.

  1 to 4 exemplify a substantially square electrode opening 5, a shape having a rectangular or hexagonal electrode opening 5 may be used. As shown in FIG. 2 showing an enlarged plan view of the portion J of FIG. 1 and FIG. 4 showing an enlarged plan view of the portion K of FIG. 3, both the electrode E1 and the electrode E2 are made of a mesh-shaped conductor. A line defect separation line G, which is an electrode and is formed by connecting the line defect parts g1, g2, g3,... Gi of mesh electrodes provided to electrically separate the electrodes E1 and E2 which are adjacent electrodes. Is non-linear.

Here, the line defect separation line G is the line defect part g1, g2, g3 as shown in FIGS. 2 and 4 which are embodiments of the present invention and FIGS. 5 and 6 which are conventional reference examples. ,..., And a hypothetical line formed by connecting the borders of the missing conductor line 2 and if it is a straight line as shown in FIG. 5 and FIG. the width perpendicular to the traveling direction of the contact break G, 2, when Ru curve der as shown in Figure 4 the width of the normal of the streak defect separation line G and defect width Ag.

  Here, the line defect separation line G of the present invention is an embodiment of the present invention without forming a straight line as shown in FIGS. 5 and 6, which is a conventional reference example, within a range in which the traveling direction does not change. As shown in FIG. 7 which is an application example, it is formed without overlapping one straight line. The running direction of the line defect separation line G indicates that the line defect separation line G is formed by extending in that direction when the electrode substrate for touch panel 1 is viewed as a whole and globally. In particular, in the case of FIG. 7 which is an application example of the present invention having portions with different electrode widths, the line defect separation line G formed by the sensor electrode Ey and the dummy electrode Ed extending in the Y direction is shown in FIG. ) In the enlarged range of the portion M shown on the right, it can be seen that it extends in one direction, but in the range shown on the left of (b), it can be seen that the extending direction has changed. .

  Thus, by arranging the line defect separation line G in a non-straight line, it was compared with the line defect separation line G arranged in a straight line as shown in FIGS. 5 and 6 shown in the conventional reference example. In this case, the visibility with human eyes is greatly reduced. Therefore, the wiring board for a touch panel of the present invention can eliminate the appearance defect due to the visual recognition of the line defect separation line G.

In the present invention, the period T of the mesh shape that constitutes the electrode is the minimum length in the length of the repeating unit of the line-and-space consisting of the conductor wire strip portion 2 and the electrode opening portion 5 constituting the electrode. To do. At this time, the defect width Ag and the period T of the mesh shape are
Ag ≦ T
This is because, when the defect width Ag exceeds the mesh-shaped period T, a conspicuous defect is generated in the line defect parts g1, g2, g3,. This is presumed to be due to the occurrence of a portion where the intersections of the conductor line portions 2 having a relatively high density of the conductive material are missing continuously.

Mesh shape of the adjacent electrodes is desirable for inconspicuous most if the same shape formed in a continuous period T. However, if one corresponds to an integer multiple of the other pattern, it can be made inconspicuous if it is arranged so that several smaller patterns are aligned with the larger pattern.

  The lower limit of the line width of the conductor wire portion 2 is preferably 1 μm or more, 3 μm or more, 4 μm or more, or 5 μm or more, and the upper limit is preferably 15 μm, 10 μm or less, 9 μm or less, or 8 μm or less. When the line width of the conductor wire portion 2 is reduced, the visible light transmittance as the whole electrode is increased, and the visible light reflectance is decreased, so that it is difficult to visually recognize, but on the other hand, the electrical resistance is increased, and the wire breakage, etc. This also reduces the production yield. In addition, when the line width of the conductor wire portion 2 is increased, the visible light transmittance as the whole electrode is reduced, and the visible light reflectance is increased, so that it is easy to visually recognize, but the electrical resistance is reduced, and the wire breakage, etc. Defects in the manufacturing process due to can be reduced.

  The line spacing is preferably 30 μm or more and 2000 μm or less, more preferably 50 μm or more and 400 μm or less, and most preferably 100 μm or more and 350 μm or less. When the line spacing is increased, the aperture ratio is improved when the electrode is viewed as a whole, the visible light transmittance is high, the visible light reflectance is lowered, but the electrical resistance is lowered. On the other hand, when the line spacing is small, the aperture ratio is improved and the visible light transmittance is high and the visible light reflectance is low but the electrical resistance is low when viewed as the whole electrode.

  Moreover, the line width of the conductor wire | line part 2 may have a part whose line width is wider than 2000 micrometers for purposes, such as ground connection.

  The aperture ratio of the electrode E in the present embodiment is preferably 85% or more, more preferably 90% or more, and most preferably 95% or more from the viewpoint of visible light transmittance. The aperture ratio is the ratio of the translucent portion excluding the conductor line portion 2 formed of the conductor material from the electrode formation area, for example, a square lattice shape with a line width of 15 μm and a pitch of 300 μm. The aperture ratio is 90%.

  When used as a normal touch panel display device, the conductor line portion 2 is made of a conductor material having a line width of 3 μm or more and 10 μm, and a line pitch of 200 μm or more and 500 μm or less is preferable because of a good balance between electric resistance and visibility. It is.

  As the conductor material, a highly conductive metal such as copper, gold, silver, platinum, tin, aluminum, nickel, and an alloy containing these metals can be used. In particular, these highly conductive metals have an advantage that the surface electrical resistivity of the surface on which the sensor electrodes (Ex, Ey) are formed can be reduced as compared with metal oxide thin films such as ITO thin films and IZO thin films.

  The thickness of the conductor line portion 2 can be selected from 0.1 μm to 200.0 μm, but is preferably 30.0 μm or less, more preferably 20.0 μm or less, and 1.0 to It is more preferable that it is 10.0 micrometers, and it is most preferable that it is 2.0 micrometers-5.0 micrometers. The conductor wire strip portion 2 may be a single layer or may have a multilayer structure of two or more layers. When the conductor line part 2 is a pattern and has a multilayer structure of two or more layers, different color sensitivities can be imparted so that it can be exposed to different wavelengths. Thereby, when the exposure wavelength is changed and exposed, a different pattern can be formed in each layer.

  The thickness of the conductor line portion 2 is preferable for the purpose of the touch panel because the viewing angle of the display panel becomes wider as it is thinner, and a thin film is also required from the viewpoint of improving the visibility. From such a viewpoint, the thickness of the layer made of the conductive metal carried on the conductive metal portion is preferably less than 15 μm, more preferably 0.1 μm or more and less than 12.0 μm. More preferably, it is 1 μm or more and less than 9.0 μm.

  If the conductor strip 2 is allowed, the surface electrical resistivity is higher than that made of metal, but it is not completely transparent like an ITO thin film or an IZO (indium zinc oxide) thin film. It may be formed of a transparent conductive film in which the pattern can be visually recognized if the user gazes.

[Sensor electrode]
The sensor electrode Ex extending in the X direction is composed of a conductor line portion 2 and an electrode opening 5 formed of a conductor material so as to extend in the X direction on the sheet surface of the transparent insulating substrate 3. The sensor electrode Ey extending in the direction is composed of a conductor line 2 and an electrode opening 5 formed of a conductor material so that the sheet surface of the transparent insulating substrate 3 extends in the Y direction. Here, the X direction and the Y direction exemplify different directions perpendicular to the sheet surface for convenience. However, from the viewpoint of detecting the touch position as the sensor electrode, the X direction and the Y direction do not have to be perpendicular to each other, and may be provided extending in two directions that intersect (not parallel) on the sheet surface. .

  The sensor electrode Ex extending in the X direction and the sensor electrode Ey extending in the Y direction are the sensor electrode extending in the Y direction in one direction (surface) of the transparent insulating substrate 3 as described in FIG. It may be provided on the respective surfaces of the sensor electrode extending in the X direction and the transparent insulating substrate 3 on the back surface. Further, both of the sensor electrode Ex extending in the X direction and the sensor electrode Ey extending in the Y direction may be provided on one of the surfaces. When both the sensor electrode Ex extending in the X direction and the sensor electrode Ey extending in the Y direction are provided on one surface of the transparent insulating substrate 3, the sensor electrode Ex extending in the X direction and the sensor electrode extending in the Y direction. In order to prevent Ey from being short-circuited, it is necessary to provide an insulating layer at the intersection of at least the sensor electrode Ex extending in the X direction and the sensor electrode Ey extending in the Y direction so as to be electrically independent.

Each of the sensor electrodes (Ex, Ey) may have a line shape extending on a straight line extending in the X direction and the Y direction, and while extending in the X direction and the Y direction as in the application example shown in FIG. it may be shaped as the width of the electrode changes.

[Dummy electrode]
In the present invention, as shown in FIG. 7, the dummy electrode is a sensor electrode Ex extending in the X direction on both surfaces of the transparent insulating substrate 3 when viewed through at least the thickness direction (Z direction), and a sensor extending in the Y direction. The X direction sensor electrode Ex and the Y direction sensor electrode Ey may be provided in an electrically non-contact manner on at least one surface (front surface) or the other surface (back surface) of a portion where none of the electrodes Ey exists. The dummy electrode Ed is composed of a conductor line portion 2 and an electrode opening portion 5 made of parallel line groups in different directions. Considering the electrode opening 5 as a center, it can be said that the electrode opening 5 is surrounded and formed by the conductor wire portion 2 formed of a conductor material.

  In view of the performance required for the touch panel electrode substrate 1, the dummy electrode Ed may be electrically independently formed on at least a part of a portion other than where the sensor electrodes (Ex, Ey) are formed. . In a portion where either the sensor electrode Ex extending in the X direction or the sensor electrode Ey extending in the Y direction is provided, the transparent insulating substrate 3 is formed on a part or all of the facing surface provided with the sensor electrode. Also good. Moreover, you may form in both surfaces of the part in which neither X direction sensor electrode Ex and Y direction sensor electrode Ey are provided. Thus, if either of the sensor electrode and the dummy electrode is provided on both surfaces of the transparent insulating substrate 3, the reflectance of visible light between the sensor electrode forming portion and the portion where the sensor electrode is not formed, The difference in visible light transmittance can be minimized. However, since the visible light transmittance is such that a double mesh electrode is formed at all sites, the visible light transmittance is reduced and the light emitted from the display device becomes dark. Need attention.

  The dummy electrode Ed provided in the present invention is formed for the purpose of matching the transmittance and reflectance of visible light with the portion where the sensor electrodes (Ex, Ey) are provided, and the formed sensor electrode (Ex , Ey) is preferably made of a material having a visible light transmittance and a visible light reflectance similar to those of the conductor wire strips 2 constituting Ey).

  Considering the ease of manufacturing and the manufacturing cost, it is realistic to form the sensor electrode (Ex, Ey) at the same time as the sensor electrode with the same material on the same plane.

  In the application example described in FIG. 7, the linear defect portions g 1, g 2, g 3,... Gi are formed simultaneously with the Y-direction sensor electrode Ey provided on the back surface so that the Y-direction sensor electrode Ey is not electrically contacted. The Y direction sensor electrode Ey is formed of the same material, the same conductor wire 2 with the same width and line pitch.

[Method of forming sensor electrode and dummy electrode]
As a method of forming the pattern of the sensor electrode (Ex, Ey), for example, by etching using photolithography of a metal thin film or by etching with a printing resist, and further by a method such as printing of a conductive resin paste material, lift-off, etc. Can be formed. The metal thin film to be etched is formed by vacuum deposition, sputtering, ion plating, plating, or bonding of metal foil.

  The pattern formation method of the dummy electrode Ed can be basically formed by the same method as the sensor electrodes (Ex, Ey). The formation of the sensor electrode (Ex, Ey) and the formation of the dummy electrode Ed may be independent processes. However, it is usually more cost effective to form the sensor electrode (Ex, Ey) on the same plane as the sensor electrode (Ex, Ey). To be effective and effective. The sensor electrodes (Ex, Ey) and the dummy electrode Ed formed on the same plane are simultaneously formed by the same process.

  When the pattern of the sensor electrode (Ex, Ey) and the dummy electrode Ed is formed by photoetching, a photoresist film is formed on the metal film and exposed using a photomask having the pattern of the sensor electrode and the dummy electrode Ed. Then, by developing with a developing solution, the pattern of the sensor electrode (Ex, Ey) and the dummy electrode Ed of the resist film is formed. This is etched with an etching solution, and the resist film is peeled and removed to form a pattern of the sensor electrode (Ex, Ey) and the dummy electrode Ed.

  In the case of forming with a printing resist, the pattern of the resist film sensor electrodes (Ex, Ey) and the dummy electrode Ed is printed on the metal film by a method such as screen printing, gravure printing, inkjet, etc. A portion of the film other than the resist coating portion is etched, and the resist film is peeled off to form a network pattern of the metal film.

In the case of forming by conductive paste printing, the pattern of the sensor electrode (Ex, Ey) and the dummy electrode Ed is printed on the transparent substrate with a conductive paste containing metal fine particles, carbon paste, or the like, and the conductive sensor electrode And a pattern of dummy electrodes is formed.

  In the case of forming by a printing method using a conductive paste containing metal powder and a binder resin, a thermosetting resin, an ionizing radiation curable resin, a thermoplastic resin, or the like can be used as the binder resin. Among them, the acrylate ionizing radiation curable resin is a kind of a preferable resin because it cures quickly and is excellent in the strength of the conductor wire portion 2.

  Further, when the pattern of the sensor electrode (Ex, Ey) and the dummy electrode Ed is formed by the lift-off method, the sensor electrode (Ex, Ey) and the dummy are formed on the transparent insulating substrate 3 with a liquid resist or a dry film resist. A reverse pattern of the electrode Ed is formed. Subsequently, after forming a metal vapor deposition layer or filling a conductive paste containing a metal powder and a binder resin, the resist pattern and the dry film resist are peeled off, whereby the sensor electrode (Ex, Ey) and the dummy electrode Ed. Can be formed. The formation by the lift-off method has high uniformity in the line width of the sensor electrode (Ex, Ey) and the dummy electrode Ed, and is suitable as the manufacturing method of the present invention.

[Touch panel]
The touch panel according to the present invention is an input device including the touch panel electrode substrate 1 described above.

  The electrode substrate 1 for a touch panel is incorporated into the touch panel in a form in which necessary portions of the sensor electrodes (Ex, Ey) are left and unnecessary portions are removed and a necessary electrode pattern is formed. Alternatively, the touch panel electrode substrate 1 may be formed with a necessary electrode pattern from the formation of the sensor electrodes (Ex, Ey). The electrode substrate 1 for a touch panel incorporated in the touch panel may be a pattern formed by other conductive layers such as wiring other than the electrode pattern, or a part or all of the pattern.

  The surface-type capacitive touch panel may have a terminal electrode pattern uniformly on one side of the transparent insulating substrate 1 on the extension of the detection electrode. Alternatively, terminal electrode patterns may be provided collectively at positions convenient for mounting, and the detection electrodes 2 to the terminal electrodes may be connected by wiring. A plurality of wirings connected to the outer periphery of the terminal electrode pattern are connected to a control circuit provided outside the transparent insulating substrate 3 via a flexible wiring board (not shown), and drive and input position detection is performed by this control circuit. Is done.

  As for the formation surface of the surface sensor electrode Ey and the back surface sensor electrode Ex, there exist the aspect formed in the same surface of the transparent insulating substrate 1, and the aspect formed in a different surface, respectively. In the latter form formed on different surfaces, an aspect formed separately on both the front and back surfaces of the same transparent insulating substrate 1 and an embodiment formed separately on each one surface of two different transparent insulating substrates 3. There is.

  In the case where the front surface sensor electrode Ey and the rear surface sensor electrode Ex are formed on the same surface, although not shown, the front surface sensor electrode Ey and the rear surface sensor electrode Ex are insulated from each other at the intersection as in the conventional case. By providing the layer, the conductive layer, and the like, the front surface sensor electrode Ey and the back surface sensor electrode Ex are electrically insulated from each other.

  The plurality of front surface sensor electrodes Ey and back surface sensor electrodes Ex are connected to a control circuit provided outside the transparent insulating substrate 1 via wiring, respectively, via a flexible wiring substrate (not shown), and driven by this control circuit. And input position detection is performed.

  The basic configuration of the capacitive touch panel has been described above, but in addition to the above-described components, known members such as a connector, a protective glass, and a protective film provided according to product specifications may be included.

[Add protection layer]
As a method of forming a protective layer on the sensor electrode (Ex, Ey), for example, it is formed by bonding a transparent film or a transparent plate on the sensor electrode (Ex, Ey) using a transparent adhesive or adhesive. It can also be formed by applying a transparent resin to the sensor electrode (Ex, Ey) with a predetermined thickness. Further, a translucent electrode is formed by inserting a transparent film on which sensor electrodes (Ex, Ey) are formed into an injection mold and injecting a molding resin into a cavity (so-called insert molding). A molded plate can be integrated on the electrode surface side of the film to form a protective layer. In this case, the surface on which the touch input surface and the sensor electrodes (Ex, Ey) of the touch panel electrode substrate 1 are formed is a three-dimensional curved surface. And can. If the surface on which the sensor electrode (Ex, Ey) of the touch panel electrode substrate 1 is formed by insert molding is a three-dimensional curved surface, cracks may occur due to deformation during molding if the electrode is made of conventional ITO. However, in the case of the present invention, since the selection line width of the electrode material is wide, a material resistant to deformation can be selected. Further, the integrally molded product obtained by the insert molding may use the transparent insulating substrate 3 as a touch input surface.

[Addition of coloring filter]
The touch panel according to the present invention preferably includes the color filter as a constituent layer in order to make the flicker less noticeable when the image has a fine flicker when the touch panel is installed on the display surface side of the display panel.

[Addition of anti-reflection treatment]
The antireflection treatment can be applied to the image observer side surface, the display panel side surface, or both the image observer side surface and the display panel side surface of the touch panel having the touch panel electrode member 1 according to the present invention as a constituent element. When antireflection treatment is performed on the surface of the image observer, it is possible to prevent image whitening due to reflection of extraneous light such as sunlight and electric light, and deterioration of image visibility due to reflection of surrounding scenery. When the antireflection treatment is performed on the display panel side surface, it is possible to prevent the occurrence of interference fringes (Newton ring, etc.), ghost images, and the like due to optical multiple reflection between the display panel and the touch panel. As such an antireflection treatment, a conventionally known one can be appropriately employed. For example, the following (1) to (3) can be adopted.

(1) An antireflection layer comprising a single layer of a low refractive index layer or a multilayer structure in which a low refractive index layer and a high refractive index layer are alternately laminated so that the low refractive index layer is positioned at the uppermost layer. Silicon oxide, magnesium fluoride, fluorine-containing resin or the like is used for the low refractive index layer, and titanium oxide, zinc sulfide, zirconium oxide, niobium oxide or the like is used for the high refractive index layer. Here, the high (low) refractive index layer is relatively higher in refractive index of the layer than the layer adjacent to the layer (for example, the transparent insulating substrate 1 or the low (high) refractive index layer). It means high (low).

(2) A process of roughening the outermost surface on which light is incident in order to scatter or diffuse extraneous light. For this roughening treatment, a method of forming a rough surface directly on the surface of the substrate by sandblasting or embossing or the like; and roughening the surface of the substrate with a resin binder that is cured by radiation or heat, or a combination thereof, Examples include a method of providing a roughened layer with a coating film containing inorganic particles such as silica or organic particles such as resin particles as light diffusing particles; and a method of forming a porous film with a sea-island structure on the surface of the substrate. be able to. As the resin of the resin binder, a thermosetting or ionizing radiation curable acrylic resin, polyester resin, epoxy resin, urethane resin, or the like is preferably used because the surface strength is desired as the surface layer.

(3) As disclosed in Japanese Patent No. 4406553, Japanese Patent No. 4265729, Japanese Patent No. 4632589, and the like, the surface includes a group of minute protrusions arranged so that the distance between adjacent protrusions is less than the shortest wavelength in the visible light wavelength band. Processing to form a micro uneven structure. The microprotrusions are shaped so that the cross-sectional area at a virtual cut surface perpendicular to the thickness direction decreases as it goes to the outside (adjacent air side). Such a fine concavo-convex structure continuously changes the refractive index of the surface portion with respect to incident light in the thickness direction from the refractive index of the material constituting the microprotrusions toward the refractive index of the external medium (usually air). To function. This can reduce light reflection caused by the refractive index discontinuity at the interface between the object and the external medium.

  In the touch panel of the present invention, the line defect separation line G is hardly visible. Furthermore, since the sensor electrodes (Ex, Ey) can be formed with low resistance, they are particularly suitable for large touch panels.

[Image display device]
An image display device according to the present invention is an image display device having a configuration in which the touch panel described above is arranged on the display surface side of a display panel. In addition, the capacitive touch panel image display device may be formed by providing a transparent adhesive layer on one surface of the touch panel and pasting it on an image display screen such as a display. The touch panel may be simply arranged on the image display screen. . Further, the transparent adhesive layer may be formed with a transparent adhesive on the entire surface, or an adhesive having no transparency may be formed with a portion requiring transparency as an opening. In addition, when providing a transparent adhesive layer, until it adheres a capacitive touch panel to a display screen, generation | occurrence | production of foreign materials, such as dust, can be suppressed by making it coat | cover with a peeling sheet.

  Further, there are various methods for taking electrode terminals in the capacitive touch panel image display device, but all known ones are applicable to the present invention. The exposed surface of the detection electrode can be used as an electrode terminal.

The image display device is a device having a configuration including at least a display panel and the touch panel of the present invention disposed on a light exit surface (screen) of the display panel. The display panel may be a liquid crystal display panel, a plasma display panel, an EL (electroluminescence) panel, various display panels such as electronic paper, or a cathode ray tube.

  The image display device using the touch panel of the present invention can detect a touch position with high sensitivity even in a large application of several tens of inches or more such as an electronic blackboard. Furthermore, the line defect separation line G is hardly visible when the display screen is turned on or off. An image display device using the touch panel of the present invention utilizing the display function of the display panel can be realized.

The use of the electrode substrate 1 for a touch panel according to the present invention and the touch panel is not particularly limited. For example, the display panel or black and white or color prints represented by halftone dots. The image display device of the present invention is a television receiver device, a computer device, a telephone, a measuring instrument, a medical device, an amusement device, an office device, an automatic teller machine, an electronic blackboard, an electronic book terminal, an electronic signboard, a vending machine, etc. The present invention can be widely applied to image display devices provided with input means in a display unit or the like.

DESCRIPTION OF SYMBOLS 1 Electrode board | substrate for touchscreens 2 Conductor line part 3 Transparent insulation board | substrate 5 Electrode opening part g1, g2, g3, ..., gi Line | wire defect | deletion part G Line defect | deletion separation line Ag Deletion part width E, E1, E2, E3 Electrode Ex (extended in the X direction) sensor electrode Ey (extended in the Y direction) sensor electrode Ed dummy electrode T period of mesh shape

Claims (3)

In a plurality of mesh-shaped electrodes (E) composed of a plurality of conductor wire strips (2) formed of a conductor on at least one surface of the transparent insulating substrate (1), the adjacent electrodes the conductor linear portions provided to electrically isolate between the (E1, E2) striatum defect of (2) (g1, g2, g3, ..., gi) linear defect fraction comprising been chosen contact break (G) is in the form of non-linear, the width of each defect (Ag) is Ri period (T) hereinafter der mesh shape forming the electrode,
The width of the electrode changes so as to repeat wide and narrow in its extending direction,
The linear defect separation line extends repeatedly by bending to one side and bending to the other side,
The distance along the longitudinal direction of the linear defect separation line at the portion of the linear defect separation line that bends to one adjacent side is greater than the distance along the longitudinal direction of the two adjacent narrow portions of the electrode. An electrode substrate for a touch panel, characterized by being short .   A touch panel using the electrode substrate for a touch panel according to claim 1.   An image display device using the touch panel according to claim 2.

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