JP5667938B2 - Capacitive touch panel - Google Patents

Description

  The present invention relates to a conductive sheet suitable for use in a projected capacitive touch panel, a method of using the conductive sheet, a manufacturing method, and a capacitive touch panel.

In general, a capacitive touch panel is a position input device that detects a fingertip position by detecting a change in capacitance between a human fingertip and a conductive film. There are surface type and projection type. The surface mold as described in Patent Document 1 has a simple structure, but cannot detect contact (multi-touch) at two or more points at the same time. On the other hand, the projection type has a configuration in which a large number of electrodes are arranged in a matrix, for example, like a pixel configuration of a liquid crystal display device. The first electrode group is arranged in the horizontal direction, and a plurality of second electrode groups in which a plurality of electrodes arranged in the horizontal direction are connected in series are arranged in the vertical direction. Multi-touch can be detected by sequentially detecting capacitance changes with the second electrode group. As a prior art of this projected capacitive touch panel, for example, there are capacitive input devices described in Patent Documents 2 and 3.
As shown in FIG. 7A of Patent Document 2, the touch switch described in Patent Document 2 includes a first auxiliary line (24b) formed between the first electrodes (14b) on one surface of the substrate, As shown in FIG.7 (b), it is provided with the 2nd auxiliary line (26b) formed between 2nd electrodes (16b) in the other surface of a board | substrate, The conductor line of a 1st electrode, 1st auxiliary | assistant When the first electrode and the second electrode are seen through from the upper part of the panel, a plurality of lattice shapes with equal line intervals are formed by the lines, the conductor lines of the second electrode, and the second auxiliary lines. The entire surface is a mesh with no gaps. However, this method requires extremely high accuracy for the superposition of the first electrode and the second electrode, and easily causes an overlap portion and a gap, and as a result, a problem that the line thickness and the gap are visually recognized is likely to occur.
As shown in FIG. 6, the touch panel described in Patent Document 3 describes a configuration in which the upper electrode on the touch side is an electrode in which conductive thin wires are bundled, and the lower electrode is a bar electrode made of ITO. It is intended to increase the responsiveness by reducing the upper electrode from inhibiting the electrostatic coupling with the electrode. However, this method tends to cause problems related to the visibility of the image, such as easy to pick up moire and that the difference in reflection due to the difference between the upper and lower electrodes is easily recognized as a subtle color difference.

JP 2006-344163 A International Publication No. 2010/013679 International Publication No. 2010/014683

  The present invention has been made in consideration of the above-described problems, and an object of the present invention is to provide a touch panel that can prevent interference fringes generated between pixels of a display for display and maintain an image that is easy to visually recognize. And Another object of the present invention is to provide a touch panel that is excellent in responsiveness even in a large area and can be multi-touched.

<1>
At least a transparent material layer constituting the touch surface, an upper electrode layer having a plurality of sensor electrodes, an insulating layer, a lower electrode layer having a plurality of sensor electrodes and arranged orthogonal to the arrangement direction of the upper electrode, one or more transparent layers A capacitive touch panel having a multilayer structure including a base layer, wherein the sensor electrode constituting the upper electrode layer has a mesh shape made of a grid of conductive thin wires, and the direction of the fine wires of the grid is the direction of the sensor electrode It has an inclination angle of 30 ° or more and 60 ° or less with respect to the arrangement direction,
The upper electrode has a non-conductive belt-like boundary region formed between adjacent sensor electrodes of the plurality of sensor electrodes constituting the electrode, and the non-conductive belt-like boundary region breaks the mesh-like conductive thin wire A capacitive touch panel that is formed by removing the width of the belt-like boundary region and randomly changes in the extending direction of the sensor electrode.
<2>
<1> The capacitive touch panel according to <1>, wherein an average value of the width of the belt-like boundary region is 15 μm or more and 70 μm or less.
<3>
The capacitive touch panel as described in <1> or <2>, wherein the maximum value rdmax of the width of the strip boundary region is 100 μm or less and the minimum value rdmin of the width is 10 μm or more.
<4>
The ratio of the standard deviation of the width of the strip boundary area to the average value of the width (standard deviation of the width / average value of the width) is 0.20 or more and 0.65 or less, from <1> to < The capacitive touch panel according to any one of 3>.
<5>
The capacitance type touch panel according to any one of <1> to <4>, wherein a width of the mesh-like conductive fine wire of the upper sensor electrode is 0.5 μm or more and 10 μm or less.
<6>
<1> to <5>, wherein the mesh-like conductive thin wire of the upper sensor electrode has a metal or alloy layer and a blackening layer formed on the layer. Capacitive touch panel.
<7>
<6> The capacitive touch panel according to <6>, wherein the thickness of the metal layer or the alloy layer of the mesh-like conductive thin wire of the upper sensor electrode is 0.1 μm or more and 3 μm or less.
<8>
The capacitive touch panel as described in <6> or <7>, wherein the blackening layer has a thickness of 0.1 μm or more and 3 μm or less.
<9>
The capacitance type touch panel according to any one of <1> to <8>, wherein a width of each of the plurality of sensor electrodes constituting the upper electrode is 3 mm or more and 7 mm or less.
<10>
The capacitive touch panel according to any one of <1> to <9>, wherein each electrode material of the plurality of sensor electrodes constituting the lower electrode is ITO.
<11>
<1> to <1> characterized in that when the display part shape of the capacitive touch panel is represented by a long side and a short side, the sensor electrode constituting the upper electrode is arranged in parallel with the long side part. 10. The capacitive touch panel according to any one of 10>.
<12>
<6> to <8> The touch panel manufacturing method according to any one of <8>, wherein the mesh-like conductivity of the upper sensor electrode including the metal or alloy layer and the blackened layer formed on the layer. A method for manufacturing a touch panel, characterized by forming a fine thin wire by the following steps.
Forming the metal layer or alloy layer on a transparent substrate;
Forming an electrode pattern on the metal layer or alloy layer;
Forming a blackening layer on the metal layer or alloy layer;
Removing a blackened layer in a portion other than the electrode pattern;
The present invention relates to the above <1> to <12>, but other matters (for example, the matters described in the following 1) to 22) are also described for reference.
1) At least a transparent material layer constituting the touch surface, an upper electrode layer having a plurality of sensor electrodes, an insulating layer, a lower electrode layer having a plurality of sensor electrodes and arranged perpendicular to the arrangement direction of the upper electrode, one or more layers A capacitive touch panel having a multi-layer structure including a transparent substrate layer, wherein the sensor electrode constituting the upper electrode layer has a mesh shape composed of a grid of conductive thin lines, and the direction of the fine lines of the grid is a sensor A capacitive touch panel having an inclination angle of 30 ° or more and 60 ° or less with respect to the electrode arrangement direction.
2) The upper electrode has a non-conductive belt-like boundary region formed between adjacent sensor electrodes of the plurality of sensor electrodes constituting the electrode, and the non-conductive belt-like boundary region is a mesh-like conductive thin wire. Item 2. The width of the belt-like boundary region is randomly changed in the extending direction of the sensor electrode, and the average value of the width is 15 μm or more and 70 μm or less. Capacitive touch panel.
3) The average value of the width of the belt-shaped boundary region is 15 μm or more and 70 μm or less, the maximum value rdmax of the width is 100 μm or less, and the minimum value rdmin of the width is 10 μm or more. Capacitive touch panel.
4) The average value of the width of the strip boundary region is 15 μm or more and 70 μm or less, and the ratio of the standard deviation of the width to the average value of the width (standard deviation of the width / average value of the width) is 0.20 or more, Item 4. The capacitive touch panel according to Item 2 or 3, wherein the capacitance type touch panel is 0.65 or less.
5) The mesh-like thin conductive wire of the upper sensor electrode has a metal or alloy layer and a blackened layer formed on the layer, or any one of items 1 to 4 Capacitive touch panel.
6) Any one of Items 1 to 5, wherein the mesh-like conductive thin wire of the upper sensor electrode is a developed silver-containing layer mainly composed of silver formed by exposure and development of photosensitive silver halide. 2. The capacitive touch panel according to item 1.
7) The capacitive touch panel according to any one of items 1 to 6, wherein a width of the mesh-like conductive fine wire of the upper sensor electrode is 0.5 μm or more and 10 μm or less.
8) The capacitive touch panel according to item 7, wherein the width of the mesh-like conductive fine wire of the upper sensor electrode is 1 μm or more and 8 μm or less.
9) The electrostatic capacity according to any one of items 1 to 8, wherein the thickness of the metal layer or the alloy layer of the mesh-like conductive thin wire of the upper sensor electrode is 0.1 μm or more and 3 μm or less. Capacitive touch panel.
10) The capacitive touch panel according to item 9, wherein the metal layer or alloy layer of the mesh-like conductive thin wire of the upper sensor electrode is 0.2 μm or more and 1 μm or less.
11) The capacitive touch panel as described in any one of items 5 and 7 to 10, wherein the blackened layer has a thickness of 0.1 μm or more and 3 μm or less.
12) The capacitive touch panel according to Item 11, wherein the blackened layer has a thickness of 0.2 μm or more and 2 μm or less.
13) The capacitive touch panel as described in any one of Items 1 to 12, wherein the developed silver-containing layer has a thickness of 0.5 μm or more and 10 μm or less.
14) The capacitive touch panel according to item 13, wherein the developed silver-containing layer has a thickness of 1 μm or more and 5 μm or less.
15) The capacitance type touch panel according to any one of items 1 to 14, wherein the width of each of the plurality of sensor electrodes constituting the upper electrode is 3 mm or more and 7 mm or less.
16) The capacitive touch panel according to any one of items 1 to 15, wherein the electrode material of each of the plurality of sensor electrodes constituting the lower electrode is ITO.
17) From the first aspect, the sensor electrode constituting the upper electrode is arranged so as to be parallel to the long side portion when the shape of the display portion of the capacitive touch panel is expressed by the long side and the short side. Item 18. The capacitive touch panel according to any one of Items 16 above.
18) In the method for manufacturing a touch panel according to items 1 to 17, forming a mesh-like conductive thin wire of an upper sensor electrode having a metal or alloy layer and a blackened layer formed on the layer by the following steps. A method for manufacturing a touch panel.
Forming a metal layer or alloy layer on the transparent substrate;
Forming an electrode pattern on the metal layer or alloy layer;
Forming a blackening layer on the metal layer or alloy layer;
Removing the blackened layer in portions other than the electrodes;
19) In item 18, in the step of forming an electrode pattern on the metal layer or alloy layer, a photomask which is a negative image of the electrode pattern is exposed in close contact with the metal layer or alloy layer, and then exposed by photolithography. A manufacturing method of a touch panel, which is a manufacturing method for forming a pattern.
20) The method for producing a touch panel according to any one of items 1 to 17, wherein the mesh-like conductive fine wire of the upper sensor electrode made of the developed silver-containing layer is formed by the following steps.
Providing a silver halide photosensitive material layer on a transparent substrate;
Exposing the halogenated photosensitive material layer in a pattern;
A step of developing the pattern-exposed silver halide photosensitive material layer to form a mesh-like conductive fine line pattern.
21) In the item 20, in the step of exposing the halogenated photosensitive material layer in a pattern, the photomask which is a negative image of the electrode pattern is exposed in close contact with the silver halide photosensitive material layer, and thereafter developed by a developing method A method for manufacturing a touch panel, which is a manufacturing method for forming an electrode pattern of developed silver.
22) An image of a random non-conductive boundary region between two electrodes of the photomask according to Item 19 and Item 21 is an image of a random boundary region width formed by generating a random number. A method for manufacturing a touch panel, comprising using a photomask having a ratio of a standard deviation of width to an average value of width (standard deviation of width / average value of width) of 0.20 or more and 0.65 or less.

  As described above, according to the electrode layer, the electrode layer manufacturing method, and the touch panel using the electrode layer according to the present invention, the resistance of the upper electrode can be reduced and the touch sensitivity of the lower electrode can be improved. Therefore, it is possible to obtain a large-area projected capacitive touch panel. In addition, it is possible to reduce the moire when the image display device is equipped with the touch panel of the present case, and it is possible to obtain a touch panel that eliminates difficulty in viewing the display screen due to the thickening of the touch sensor electrodes.

It is sectional drawing of the touch panel 10 of this invention. 2a is an example of an array diagram of sensor electrodes in the upper electrode layer. 2b is a diagram showing a mesh structure which is a detailed structure of the sensor electrode. 3a is a diagram showing a sensor electrode and a non-conductive boundary region between the electrodes. 3b is a diagram showing a non-conductive boundary region between electrodes. It is an arrangement | sequence diagram of the sensor electrode in a lower electrode layer. It is the figure which saw through the panel from the toucher side. It is an example of the formation method of the sensor electrode in an upper electrode layer. It is another example of the formation method of the sensor electrode in an upper electrode layer. It is another example of the arrangement | sequence diagram of the sensor electrode in an upper electrode layer. It is an example of the figure for forming the nonelectroconductive boundary area between two electrodes. It is an example of the drawing for giving randomness to the width of the nonconductive boundary area between two electrodes. It is an example of drawing for giving randomness to the width of the nonconductive boundary area between two electrodes. It is another example of the drawing for giving randomness to the width of the nonconductive boundary area between two electrodes.

Hereinafter, embodiments of the touch panel according to the present invention and the components of the touch panel of the present invention will be described with reference to FIGS.
In the present specification, “to” is used as a meaning including numerical values described before and after the lower limit value and the upper limit value.

The present invention provides a projected capacitive touch panel that is excellent in responsiveness even in a large area and capable of multi-touch, as described in the section “Problems to be Solved by the Invention” above. In addition, when the projected capacitive touch panel is mounted on an image display device, the present invention is intended to prevent the display image of the image display device from being easily viewed.
Of the above objectives, the first part is a problem for dealing with a large screen that is expected to develop in the future. Specifically, in the present invention, it is considered that the resistance of the conductive thin wire forming the touch sensing portion of the sensor electrode is lowered and the efficiency of the electrostatic coupling between the lower electrode and the finger to be touched is improved.
Further, among the above-mentioned purposes, as a factor that impairs the visibility of the display image of the image display device, there is a problem of the occurrence of moiré, a sensor electrode with low light transmittance is visually recognized, and there is coloring. As a problem of non-uniform appearance such as unevenness due to different reflectances.

FIG. 1 shows a cross-sectional view of a touch panel 10 of the present invention. FIG. 1A shows, from the toucher side, a transparent material layer 16 constituting a touch surface, an adhesive layer 19 also serving as an insulating layer, and a plurality of sensor electrodes. A capacitive touch panel having a multilayer structure comprising an upper electrode layer 11 having a transparent substrate layer 15 also serving as an insulating layer, an adhesive layer 19 also serving as an insulating layer, a lower electrode layer 12 having a plurality of sensor electrodes, and a transparent substrate layer 17. Is illustrated. FIG. 1B shows, from the toucher side, a transparent material layer 16 constituting a touch surface, an adhesive layer 19 also serving as an insulating layer, an upper electrode layer 11 having a plurality of sensor electrodes, a transparent substrate layer 15 also serving as an insulating layer, and a plurality of layers. This example illustrates a capacitive touch panel having a multilayer structure including a lower electrode layer 12 having the sensor electrode, an adhesive layer 19 also serving as an insulating layer, and a transparent substrate layer 18 also serving as electrode protection.
Although not shown in the figure, the arrangement direction of the plurality of sensor electrodes of the upper electrode and the arrangement direction of the plurality of sensor electrodes of the lower electrode are set so as to be orthogonal to each other, and multi-touch is possible. It has a configuration.
FIG. 1 (a) shows a preferable configuration when the upper electrode and the lower electrode are formed on separate transparent substrates, and FIG. 1 (b) shows that the upper electrode and the lower electrode are formed on the front and back surfaces of one transparent substrate. In this case, a preferable configuration is shown.
Hereinafter, each of the above components will be described.

[Transparent material layer, transparent substrate layer]
The transparent material used for the transparent material layer 16 constituting the touch surface, the transparent substrate layer 15 also serving as an insulating layer, the transparent substrate layer 17 and the transparent substrate layer 18 also serving as electrode protection may be the same material or different from each other. Materials may be used, and plastic films, plastic plates, glass plates and the like are used. It is desirable that the thickness of the layer is appropriately selected according to each application.

  Examples of the raw material for the plastic film and plastic plate include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN); polyolefins such as polyethylene (PE), polypropylene (PP), polystyrene, and EVA; Resin; In addition, polycarbonate (PC), polyamide, polyimide, acrylic resin, triacetyl cellulose (TAC) and the like can be used.

  Preferred materials include PET (melting point: 258 ° C.), PEN (melting point: 269 ° C.), PE (melting point: 135 ° C.), PP (melting point: 163 ° C.), polystyrene (melting point: 230 ° C.), polyvinyl chloride (melting point) : 180 ° C), polyvinylidene chloride (melting point: 212 ° C), TAC (melting point: 290 ° C) or other plastic film or plastic plate having a melting point of about 290 ° C or less is preferable. From the viewpoint of PET, PET is preferable. The thickness of the film or plate is preferably 50 μm to 300 μm.

  For the pressure-sensitive adhesive layer 19 that also serves as an insulating layer, an adhesive having no conductivity can be used. There are various types of adhesives, among which acrylic resin, epoxy resin, phenol resin, vinyl resin, and the like are used. There is no particular limitation on the method for forming the layer, but a screen printing method or the like can be used.

FIG. 2 is a diagram for explaining the upper electrode layer 11 of the present invention. FIG. 2A shows an arrangement of a plurality of sensor electrodes (indicated by r-i) constituting the upper electrode layer. Adjacent electrodes are blocked from conduction by a non-conductive boundary region rb formed between the electrodes. It is exemplified that the electrodes indicated by r-i extend in the Y direction (the Y direction is the conduction direction of the electrodes) and i are arranged in the X direction. In the figure, rw represents the width of the sensor electrode ri, and rd represents the width of the non-conductive boundary region between the sensor electrodes.
The detailed structure of the electrode r-i is shown in FIG. 2B, and has a mesh structure with an orthogonal lattice shape. The direction of the fine wire rm of the lattice constituting the mesh is inclined at an angle θ with respect to the arrangement direction X of the electrode group ri. The angle θ is preferably 30 ° or more and 60 ° or less, and more preferably 35 ° or more and 55 ° or less. The inclination angle is provided in order to prevent the generation of moire due to interference between fine mesh lines and electrodes of the image display device. The mesh electrode can be formed in a polygon other than the above-mentioned orthogonal lattice, but it is necessary to prevent any side of the polygon from being parallel to the electrode of the image display device. Is most preferred. In the above description, the mesh is an orthogonal lattice, but may be a rhombus. In this case, two adjacent sides must satisfy the above inclination angle. Note that the tilt angle is roughly 45 ° because it is necessary to match the pixel arrangement of the image display device equipped with the touch panel of the present invention, but the absolute value of the angle needs to be optimized for each image display device. .

The width rw of the sensor electrode r-i forming the upper electrode layer is preferably 2 mm or more and 8 mm or less, and more preferably 3 mm or more and 7 mm or less. The line width of the conductive fine wires rm having a lattice-like mesh structure, which is the detailed structure of the sensor electrode ri, is preferably 0.5 μm or more and 10 μm or less, and more preferably 1 μm or more and 8 μm or less. The length of one side of the lattice constituting the mesh is preferably from 100 μm to 700 μm, and more preferably from 200 μm to 600 μm.
The sensor electrode r-i is meshed to create a large number of openings in the electrode, and through this opening, the touched finger and the lower electrode can be electrostatically coupled, improving responsiveness. Can do. The material and manufacturing method of the conductive fine wire having the mesh structure will be described below.

FIG. 3A is a diagram showing a non-conductive boundary region rb between sensor electrodes. The adjacent sensor electrode r-i and electrode r-i + 1 of the upper electrode layer of the present invention provide a non-conductive boundary region rb by providing a broken portion in a continuous uniform mesh-shaped conductive thin wire. Thus, the conduction between the sensor electrode ri and the electrode ri + 1 is interrupted.
In the prior art, the non-conductive boundary region between the sensor electrodes of the upper electrode is usually an elongated band. The width of the band is set to 100 μm or less, for example, 50 μm or less, which is a very small width that is difficult to be visually recognized. Even in this case, since the band-like body is long, the difference in light transmittance between the electrode part and the non-conductive part, difference in reflectance In some cases, it may be perceived as irregularity with regularity due to differences in inherent colors including gloss. For this reason, attempts have been made to dispose isolated thin conductive wires in the non-conductive boundary area and make the distribution of the conductive thin wires uniform in the plane. May occur.

  In the present invention, the width of the non-conductive boundary region is randomly changed in the extending direction of the sensor electrode, that is, the band is irregular and has no linearity. I tried to solve the sex problem. It is possible to improve the visibility to some extent by making the width of the boundary region the same width but not linear, for example, zigzag shape or wavy shape, but as irregularity with regularity However, it is preferable to use a band having an irregular width and no linearity according to the present invention. Below, the shape of the strip | belt body from which the width | variety of this invention changes at random, and the manufacturing method of such a strip | belt body are demonstrated.

FIG. 3B is a diagram showing a non-conductive boundary region rb formed by removing the disconnection of the mesh-like thin line in FIG. rb is a region sandwiched between the smoothed line connecting the ends of the thin lines of the sensor electrode ri and the smoothed line connecting the ends of the thin lines of the sensor electrode ri + 1, and has a band shape whose width changes randomly. Is the body. The width rd of the strip can be calculated as an average value of the distance separating the electrode ri and the electrode ri + 1. Specifically, the intersection of continuous meshes before disconnection is deleted (illustrated as cp in FIG. 3a), and the width of the boundary region rb (X direction in FIG. 3a) is measured at the intersection. The intersection points are all the intersection points in the boundary region rb, the widths at the respective intersection points are measured, the average value is obtained, and the average value rd is obtained.
In the above description, the upper electrode has been described as an example. However, in the case of the lower electrode, the average value of the width can be obtained by the same method as that for the upper electrode. In addition, when the lower electrode is not a mesh electrode, a virtual point as many as the number of intersections of the upper electrode is provided, and an average value of each width and width is obtained by a method of obtaining the width at that point. .
The width rd (average value) of the belt-like body is preferably 15 μm or more and 70 μm or less, and more preferably 20 μm or more and 50 μm or less from the viewpoint of interelectrode conduction and visibility. The maximum width rdmax is preferably 100 μm or less, and the minimum width rdmin is preferably 10 μm or more, more preferably 90 μm or less and 15 μm or more. Furthermore, on the condition that the average value of the width is 15 μm or more and 70 μm or less, the ratio of the standard deviation of the width of the boundary area to the average value of the width (standard deviation of the width / average value of the width) is 0.20 to 0.65. It is preferable. If it is less than 0.2, the boundary line approaches a straight line and there is a possibility of seeing unevenness. If it exceeds 0.65, there is a risk of conduction between adjacent electrodes.

Below, the manufacturing method of the strip | belt shaped object from which the width | variety of this invention changes at random is demonstrated. In the present invention, a desired electrode pattern is formed in the form B (utilization as a metal foil or thin film), form C (utilization of conductive ink), or form D (utilization of a silver salt photosensitive material) described later depending on the material used. In forms B and D, a desired electrode pattern is generally formed on a photomask, and in form C, an ink layer is generally provided in a desired pattern. In the forms B and D, the relationship between the pattern of the photomask and the actually formed electrode pattern may be a negative image or a positive image depending on the material used. In the following description, the photomask is In the electrode pattern formed using the above, it is assumed that a band-like body whose width is randomly changed is assumed. A photomask used in an actual manufacturing process can generate a mask pattern based on the above description.
In the band-shaped specific conductivity region in which the width between the two electrodes changes randomly, two disconnection portions are provided on a uniform mesh made of conductive thin wires, and the conductive thin wires between the two points are removed. Thus, a non-conductive belt-like boundary region that separates adjacent electrodes is formed. The present invention is an invention that improves visibility by randomly changing the width of the band when forming the band-like boundary region. Below, the example about the method of changing the width | variety of a strip | belt shaped body at random is demonstrated, referring FIG.9, FIG.10, FIG.11a, and FIG.11b.

FIG. 9 is an example of the formed uniform mesh. The left side of the drawing is an area for forming the electrode ri, the right side is an area for forming the adjacent electrode ri + 1, and a dotted line C is a center line between two adjacent electrodes. The total number of intersections between the center line C and the thin conductive wires rm is M, and the intersections are represented by c1, c2, c3,... Cm, cm + 1,. A band-like boundary region having a non-conductive and random width according to the present invention is formed based on the intersection cm between the center line C and the conductive thin wire. In the present invention, the center line c is included in the band-shaped boundary region (described below). (In the case of (1)) and in the case of including only a part of the intersection cm (in the case of (2) below). In the case of (2), since the center line C is only partially included in the random disconnection area, it is a more preferable boundary area formation method for improving visibility.
In the present invention, it is preferable that the uniform mesh composed of the conductive thin wires take the direction of θ, and the conductive thin wires are neither parallel nor perpendicular to the X direction or Y direction of the touch panel. In the following description, the conduction direction of the formed electrode ri is the Y direction (upper electrode), but the same operation can be performed when the conduction direction of the formed electrode cj is the X direction (lower electrode). .
The relationship between the disconnection length D (m) on the conductive thin wire starting from the intersection point m and the length (width) rd (m) in the X direction of the boundary region is
D (m) * cos θ = rd (m) (* represents multiplication)
In the following, for the sake of convenience, it is assumed that θ is 45 °.

Hereinafter, the case of (1) and the case of (2) will be described in detail. In both cases, the length of the portion to be broken and removed on the conductive thin wire is determined by the generation of a random number, whereby a random strip-like body having no regularity is obtained.
In both cases (1) and (2), the design values of the boundary area in the present invention are as follows.
Average width rd of the belt-like boundary region: 15 μm ≦ rd ≦ 70 μm
Relation between maximum and minimum width: 10 μm ≦ rd (m) ≦ 100 μm
Ratio of standard deviation (σ) of width and average value of width: 0.20 ≦ σ / rd ≦ 0.65

The above-mentioned design values are calculated based on the disconnection length D (m) due to the intersection cm on the conductive thin wire of the mesh, the total D (= ΣD (m)) of the disconnection length D (m), and the average disconnection length D. / M
Formula 1 15 * √2 <D / M <70 * √2
Formula 2 10 * √2 <D (m) <100 * √2
Formula 3 0.20 ≦ {σ (standard deviation of D (m)) / (D / M)} ≦ 0.65

(1) In the case where the intersection of the center line C and the conductive thin wire is left in the boundary area, the following symbols in FIG. 10 have the following meanings.
When the side of the electrode i to be created is shown, the left side of the drawing is l, and the side of the electrode i + 1 side is the right side with r.
Of the portion where the thin conductive wire rm passing through the intersection cm is removed, the length on the electrode i + 1 side is Dr (m) and the length on the electrode i side is Dl (m).
Random numbers are generated twice (on the right and left electrode sides) at each intersection m and are R (m1) and R (m2). However, 0 <R (m) <1.
If the provisional average value of the lengths of the thin wires to be removed is RB (2 * rd may be used), the length D (m) of the removed portion is D (m) = Dr (m) + Dl (m ) = RB * R (m1) + RB * R (m2). Thus, the Dr (m) and Dl (m) portions before and after the intersection cm are removed.
D (m), D, D / M, and σ (standard deviation of D (m)) obtained from the above are the non-conductive belt-like boundary regions between the electrodes under the conditions where the above Equations 1 to 3 are satisfied And the portions of Dr (m) and Dl (m) before and after the intersection cm are removed to form a band-like boundary region having a random width.

(2) Including the case where the intersection of the center line C and the conductive thin wire is not left in the boundary area Random numbers are generated twice for each intersection m, and the first time is used to determine the position of the start of disconnection. The second time is used to determine the length of the disconnection. The disconnection removal is started from the electrode i side in FIGS. 11a and 11b.
Assuming that RB is the provisional average value of the lengths of the thin lines to be disconnected, the product Dm1 of the first random number R (m1) and RB at the intersection m is the distance from the intersection of the thin lines to the point Xm1 where the disconnection starts. . A product D (m) of the second random number R (m2) and RB at the intersection m is defined as the length of the disconnection (start point Xm1, end point Xm2).
The total length D of the removed portions is D = ΣD (m) of the sum of D (1) to D (M), and the average length of the removed portions is D / M.
D (m), D, D / M, and σ (standard deviation of D (m)) obtained from the above are the non-conductive belt-like boundary regions between the electrodes under the conditions where the above Equations 1 to 3 are satisfied , And a portion between the points Xm1 and Xm2 on the conductive thin line is removed to form a belt-like boundary region having a random width.

  In the non-conductive belt-like boundary region of the present invention, dummy conductive thin wires that are not electrically connected to adjacent electrodes, which will be described in detail later, may be formed (not shown). These dummy conductive thin wires are provided with a disconnection portion of 1 μm to 10 μm on a uniform mesh pattern before forming the non-conductive belt-like boundary region, so that the band-like boundary region and the dummy conductive thin wire of the present invention are provided. A part may be formed. By doing so, the visibility is further improved.

FIG. 4 is a diagram for explaining the lower electrode layer 12 of the present invention, and shows an arrangement of a plurality of sensor electrodes (indicated by cj) constituting the lower electrode layer. The electrodes indicated by cj are illustrated as extending in the X direction and arranged in the Y direction. The electrode c-j is a so-called bar electrode having no structure in detail. In the figure, cw represents the width of the sensor electrode cj, and cd represents the width of the non-conductive boundary area between the sensor electrodes.
The sensor electrode c-j constituting the lower electrode layer is preferably a solid electrode having no opening in order to sense an electric field passing through the opening of the upper electrode. Because of the structure having no opening, a light transmissive conductive material is used as the electrode material. The light-transmitting conductive material used for the lower electrode will be described separately. The width cw of the sensor electrode of the lower electrode may be the same as the width rw of the sensor electrode of the upper electrode, but may be wider than rw due to restrictions on the display device side such as pixel pitch and display area. The width cd of the non-conductive boundary region between the sensor electrodes is preferably 15 μm or more and 70 μm or less, and more preferably 20 μm or more and 50 μm or less. The shape of the boundary region may be a belt-like body whose width changes at random like the upper electrode.

  FIG. 5 is a perspective view when the touch panel of the present invention is viewed from the toucher side. The sensor electrode group r-i constituting the upper electrode and the sensor electrode group c-j constituting the lower electrode are arranged orthogonally. It shows how it is. A rectangular area indicated by a dotted line 20 represents a touch area. When the touch area is not square, the sensor electrode group r-i that constitutes the upper electrode is arranged in parallel with the Y axis of the long side in the long side direction. In FIG. 5, the electrode groups r-i and c-j are arranged orthogonally, but may not be arranged orthogonally depending on matching with the display device equipped with the touch panel of the present invention.

Next, a conductive material and a method for forming the electrodes that can form the sensor electrodes of the upper and lower electrode layers of the present invention will be described below.
A As a light-transmitting conductive material, a conductive polymer and some metal oxides can be raised, but metal oxides are used in terms of durability and weather resistance. Transparent metal oxides include indium tin oxide (ITO), antimony doped tin oxide (ATO), tin oxide, aluminum doped zinc oxide (ZnO: Al), and indium zinc oxide (In ₂ O ₃ —ZnO). (IZO)).
In the present invention, the above transparent oxide can be used as a sensor electrode for forming the lower electrode layer. Among the above oxides, from the viewpoint of resistance value, transparency, and ease of film formation, ITO or IZO is preferably used. A sputtering method, an electron beam method, an ion plating method, or the like is used to form a thin film of ITO or IZO.

Since the sensor electrode constituting the upper electrode layer of the present invention is a mesh electrode made of a conductive thin wire, it is necessary to use a material having a lower resistance than the material for the lower electrode. Therefore, a highly conductive metal or alloy is used. It is preferable to use it. Examples of such metals include copper, silver, gold, platinum, palladium, nickel, tin, aluminum, cobalt, rhodium, iridium, iron, ruthenium, osmium, manganese, molybdenum, tungsten, niobium, tantel, titanium, and bismuth. , Antimony, lead and the like. Among these, copper, silver, gold, platinum, palladium, nickel, tin, aluminum, and alloys thereof are preferable in terms of excellent conductivity.
The following forms B to D can be used for electrode formation with these metals or alloys.
B Use as metal foil or thin film.
To use as a thin film, first form a metal thin film on the base material by vacuum deposition, sputtering, ion plating, or by plating or bonding metal foil. To do. Next, this metal thin film is subjected to the following patterning to form a mesh electrode. When the mesh pattern is formed by photoetching, a photoresist film is formed on the metal thin film, exposed using a photomask, and developed with a developer to form a resist film mesh pattern. This is etched with an etching solution, and the resist film is peeled and removed to form a mesh pattern made of fine metal wires. Alternatively, when forming with a printing resist, a mesh pattern of the resist film is printed on the metal thin film by a method such as screen printing, gravure printing, inkjet, etc., and the resist film is etched except for the resist coating portion in the metal thin film with an etching solution. A fine metal mesh pattern is formed by peeling the film.

C A method of printing the mesh pattern with an ink (or paste) containing conductive nanoparticles. In addition to the above metal fine particles, carbon may be used as the conductive nanoparticles. The conductive nanoparticles are preferably particles containing gold, silver, palladium, platinum, copper, carbon, or a mixture thereof. The average particle size of the nanoparticles is 2 μm or less, preferably 200 nm to 500 nm, and those having a particle size smaller than that of conventional micron particles are preferable for forming a mesh pattern. Screen printing or gravure printing is used for mesh pattern printing. The conductive material included in the ink (or paste) may be conductive fibers instead of metal particles. In the present case, the conductive fiber includes a metal wire, a fibrous substance called nanowire, a hollow structure tube, and a nanotube. The average minor axis length of the metal nanowire (sometimes referred to as “average minor axis diameter” or “average diameter”) is preferably 100 nm or less, more preferably 1 nm to 50 nm, still more preferably 10 nm to 40 nm, and even more preferably 15 nm. -35 nm is particularly preferred. In the case of forming a conductive layer using conductive fibers, for example, JP2009-215594, JP2009-242880, JP2009-299162, JP2010-84173, JP2010-87105, JP2010. It can be formed by combining the techniques disclosed in -86714.

D This is a method in which a silver halide photographic light-sensitive material used in photography is used, and this material is subjected to a mesh pattern exposure, followed by development and fixing to obtain a conductive fine line pattern by developed silver. The method for obtaining a conductive fine line pattern in the present invention includes the following three forms depending on the photosensitive material and the form of development processing.
(1) A mode in which a photosensitive silver halide black-and-white photosensitive material not containing physical development nuclei is chemically developed or thermally developed to form a metallic silver portion on the photosensitive material.
(2) An embodiment in which a photosensitive silver halide black-and-white photosensitive material containing physical development nuclei in a silver halide emulsion layer is dissolved and physically developed to form a metallic silver portion on the photosensitive material.
(3) A photosensitive silver halide black-and-white photosensitive material containing no physical development nuclei and an image receiving sheet having a non-photosensitive layer containing physical development nuclei are overlapped and developed by diffusion transfer, and the metallic silver portion is non-photosensitive image-receiving sheet. Form formed on top.

The aspect (1) is an integrated black-and-white development type, and a light-transmitting conductive film such as a light-transmitting conductive film is formed on the photosensitive material. The obtained developed silver is chemically developed silver or heat developed silver, and is highly active in the subsequent plating or physical development process in that it is a filament with a high specific surface.
In the above aspect (2), the light-transmitting conductive film such as a light-transmitting conductive film is formed on the photosensitive material by dissolving silver halide grains close to the physical development nucleus and depositing on the development nucleus in the exposed portion. A characteristic film is formed. This is also an integrated black-and-white development type. Although the development action is precipitation on the physical development nuclei, it is highly active, but developed silver is a sphere with a small specific surface.
In the above aspect (3), the silver halide grains are dissolved and diffused in the unexposed area and deposited on the development nuclei on the image receiving sheet, whereby a light transmitting conductive film or the like is formed on the image receiving sheet. A conductive film is formed. This is a so-called separate type in which the image receiving sheet is peeled off from the photosensitive material.

  In either embodiment, either negative development processing or reversal development processing can be selected (in the case of the diffusion transfer method, negative development processing is possible by using an auto-positive type photosensitive material as the photosensitive material). .

The chemical development, thermal development, dissolution physical development, and diffusion transfer development mentioned here have the same meanings as are commonly used in the industry, and are general textbooks of photographic chemistry such as Shinichi Kikuchi, “Photochemistry” (Kyoritsu Publishing) (Published in 1955), C.I. E. K. It is described in "The Theory of Photographic Processes, 4th ed." Edited by Mees (Mcmillan, 1977). Although this case is an invention related to liquid processing, a technique of applying a thermal development system as another development system can also be referred to. For example, the technique described in each specification of Unexamined-Japanese-Patent No. 2004-184893, 2004-334077, 2005-010752, 2004-085655 is applicable.
In addition, regarding the material and the conductive pattern manufacturing method used in the present invention, the description and technology of JP-A-2006-352073, which is an invention of a mesh-like electromagnetic wave shielding film, and Japanese Patent Application No. 2009, which is an invention of a capacitive touch panel -265467 and the technique described therein can be used.

Next, a method for forming a mesh sensor electrode constituting the upper electrode will be described.
First, a forming method in the case of use as a metal foil or a thin film (above B) as a material for forming the upper electrode layer will be described with reference to FIG. FIG. 6A shows a transparent substrate 15 that also serves as an insulating layer, for example, a PET film of about 100 μm. The surface of the film is cleaned, and then a thin layer of metal or alloy is provided on the surface of the film (FIG. 6 (b)). As the metal, the materials described in B above can be used, and silver, copper, aluminum, or an alloy thereof is preferably used. A sputtering method or the like is used as a method for forming the thin layer, but other methods may be used. The thickness of the formed metal thin layer can be appropriately adjusted according to a desired resistance value, but is preferably 0.1 μm to 3 μm, and more preferably 0.2 μm to 1 μm.
Next, a photoresist film is formed on the metal thin film formed above, exposed using a photomask, and developed with a developer to form a mesh pattern of the resist film. This is etched with an etching solution, and the resist film is peeled and removed to form a mesh pattern made of fine metal wires (FIG. 6C). The conductive fine line of the mesh pattern in which 31 of (c) of FIG. 6 was formed is represented.
Next, a coating layer is provided on the sensor electrode formed as described above ((d) in FIG. 6). In the present invention, this coating layer is called a blackening layer. The blackened layer has a visual function that makes the metallic luster of the metal or alloy inconspicuous, and a function of improving durability by preventing rust and migration of the metal. The material for the blackening layer (coating layer) will be described separately below. The thickness of the blackening layer (coating layer) is preferably 5 μm or less, more preferably 3 μm or less, and particularly preferably 0.2 μm or more and 2 μm or less.
Next, by removing the blackening layer on the visual recognition part that does not cover the fine electrode wire of the blackening layer (coating layer), it is possible to form an electrode with a mesh pattern excellent in visibility and durability. (E in FIG. 6).

Next, the forming material and forming method of the blackening layer (coating layer) will be described.
Examples of suitable methods for laminating black portions in the present invention include plating and chemical etching. Any known so-called black plating may be used as the plating treatment, such as black ni plating, black Cr plating, black Sn-ni alloy plating, Sn-ni-Cu alloy plating, black zinc chromate treatment, etc. As mentioned. Specifically, black plating bath (trade name, Nikka Black, Sn-ni alloy system) manufactured by Nippon Chemical Industry Co., Ltd., black plating bath (trade name, Ebony-Chromium 85 series manufactured by Metal Chemical Industry Co., Ltd.) -Cr, Cr) and dip sole Co., Ltd. chromate agent (trade name, ZB-541, galvanized black chromate agent) can be used. The plating method may be either electroless plating or electrolytic plating, and may be mild or high-speed plating. Although the thickness is not limited as long as the plating thickness can be recognized as black, the normal plating thickness is preferably 1 μm to 5 μm.

  In the present invention, a black portion can also be formed by oxidizing or sulfurating a part of the conductive metal portion. For example, when the conductive metal part is copper, examples of the blackening treatment agent on the copper surface include: Meltex Co., Ltd., trade name Enplate MB438A, B, Mitsubishi Gas Chemical Co., Ltd., trade name: nPE- 900, manufactured by Mec Co., Ltd., trade name: Mec Etch Bond BO-7770V, manufactured by Isolate Chemical Laboratory, trade name: Copa-Black CuO, CuS, selenium-based Copa-Black no. 65 etc. can be used. In addition to the above, for example, it is possible to treat the sulfide to generate hydrogen sulfide (H 2 S) and to blacken the copper surface as copper sulfide (CuS). The thickness of the treatment is not limited as long as it can be recognized as black, but it is preferably 3 μm or less, more preferably 0.2 μm to 2 μm.

  When ink (or paste) containing conductive nanoparticles is used (B), the mesh pattern can be directly printed on the transparent substrate layer that also serves as an insulating layer.

Next, the case of using the silver halide photographic light-sensitive material used in photography (D above) will be described with reference to FIG.
The silver halide photographic light-sensitive material used in the present invention is described in detail in JP-A No. 2006-352073, which is an invention of an electromagnetic wave shielding film using a fine line pattern of developed silver.
FIG. 7A shows a transparent substrate 15 that also serves as an insulating layer, for example, a PET film of about 100 μm. The surface of the film is cleaned, and then a thin layer 41 of a silver halide photographic light-sensitive material is provided on the surface of the film ((b) of FIG. 7). The silver halide photographic light-sensitive material contains binders such as silver halide and gelatin excellent in characteristics as an optical sensor, coating aids, and various additives for adjusting sensitivity. Coating amount of silver (coating amount of silver salt) is preferably from 1 to 30 g / ^{m 2} in terms of silver, more preferably 1 to 25 g / ^{m 2,} more preferably 5 to 20 g / ^{m 2.} By setting the coated silver amount within the above range, the conductive sheet after exposure and development processing can obtain a desired surface resistance. The thin film is preferably formed using a multilayer coater used for the production of photographic materials.

  Next, in order to form conductive thin lines on the thin layer 41 of the above-mentioned silver halide photographic light-sensitive material, a mesh pattern exposure is performed. In FIG. 7C, the area where the photosensitive nuclei are generated by exposure is indicated by 43. FIG. 7D shows the film after the development and fixing process has been performed on the exposed film. Reference numeral 44 denotes an aggregate of silver formed around the photosensitive nucleus by development. It represents the state that became. In this way, a mesh-like fine line pattern with developed silver can be formed.

In response to an increase in the size of an image display device using a touch panel, an increase in the size of the touch panel itself is also required. In order to increase the size, it is necessary to reduce the parasitic capacitance between the electrodes as well as to reduce the resistance of the electrodes. For this reason, it is considered to arrange dummy electrodes between the electrodes. FIG. 8 shows an example in which a sensor electrode and a dummy electrode are arranged on the upper electrode layer. A dummy electrode is arranged across the sensor electrode. Both the sensor electrode and the dummy electrode are electrodes composed of fine mesh wires. The distance rd between the sensor electrode and the dummy electrode is the same as the distance between the sensor electrodes when there is no dummy electrode. The width of the dummy electrode is preferably 2 mm or less. Note that ET of the sensor electrode r-i represents a terminal for connection to the external control unit, and the dummy electrode is an isolated electrode group without connection to the external control unit. However, the dummy electrode may be grounded.
FIG. 8 is an explanatory diagram of the upper electrode layer, but it is preferable to provide a dummy electrode also in the lower electrode. The width of the dummy electrode at this time is preferably 2 mm or less, and needs to be formed in the same manner as the lower sensor electrode.

Hereinafter, the present invention will be described more specifically with reference to examples of the present invention. In addition, the material, usage-amount, ratio, processing content, processing procedure, etc. which are shown in the following Examples can be changed suitably unless it deviates from the meaning of this invention. Accordingly, the scope of the present invention should not be construed as being limited by the specific examples shown below.
First, how to make the upper electrode used in the touch panel of the present invention will be described.

(Upper electrode U-1)
A PET (polyethylene terephthalate) film having an A4 size and a thickness of 100 μm was neutralized and the surface was cleaned by air blowing. Next, a thin layer of 2 μm in thickness of metallic copper was provided on the surface of this PET film by an electrolytic plating method using an electrolytic copper sulfate plating bath. Next, a photoresist film was formed on the copper thin film formed above. The photoresist film was overlaid with the following photomask, exposed, and developed with a developer to form a resist film mesh pattern in which the exposed portion was cured. This was etched with a ferric chloride etchant, and the cured resist film was peeled off to form a sensor electrode (FIG. 8) composed of conductive fine wires in a mesh pattern. The parameters of the pattern used as the photomask are as follows: the sensor electrode width rw is 4 mm, the dummy electrode width dpw is 1 mm, the electrode length and the dummy electrode length are 200 mm each, and the sensor electrode mesh conductive thin wire The width of the mesh is 4 μm, the side length of the mesh lattice is 500 μm, the inclination angle of the fine mesh wire with the X axis is 45 °, and the width of the non-conductive boundary area (disconnection) between the sensor electrode and the dummy electrode is random and average The value is 30 μm (the maximum value of the width of the boundary area is 45 μm, the minimum value is 15 μm, the ratio of the standard deviation of the width to the average value of the width is 0.35), and 20 electrodes are provided on an A4 size PET sheet. It was a pattern to be formed.

(Upper electrode U-2)
A thin metal copper layer having a thickness of 0.5 μm is formed on the upper electrode U-1 by an electroless plating method using palladium colloid as a catalyst core, a photomask pattern, and a sensor electrode width rw of 6 mm. The width dpw of the dummy electrode is 1 mm, the width of the conductive thin wire of the sensor electrode mesh is 6 μm, the side length of the mesh lattice is 600 μm, the inclination angle of the mesh thin wire with the X axis is 45 °, and between the sensor electrode and the dummy electrode The width of the non-conductive boundary region (disconnected portion) is random and the average value is 20 μm (maximum value of the boundary region is 30 μm, minimum value is 10 μm, the ratio of the standard deviation of the width to the average value of the width is 0 .35) and forming a mesh pattern sensor electrode U-2 having a coating layer in the same manner as U-1 except that the coating layer is a coating layer of metal tin having a thickness of 0.2 μm. did.

(Upper electrode U-3)
A PET film drawn out from a roll having a width of 30 cm is subjected to a cleaning treatment, and the following coating solution is applied onto the film surface so that the amount of silver applied is 8 g / m ^2, and the sample shown in FIG. It was created. At this time, the coating width is 25 cm and the coating length is 20 m, and the film having the coating layer is handled in a dark room until the development and fixing process is completed.

[Coating solution containing silver halide photosensitive material]
An emulsion containing 10.0 g of gelatin per 150 g of Ag in an aqueous medium and containing silver iodobromochloride grains having an average equivalent sphere diameter of 0.1 μm (I = 0.2 mol%, Br = 40 mol%) was prepared. . In this emulsion, K ₃ [Rh ₂ Br ₉ ] and K ₂ [IrCl ₆ ] are added so that the concentration becomes 10 ⁻⁷ (mol / mol silver), and Rh ions and Ir are added to the silver bromide grains. Doped with ions. Na ₂ PdCl ₄ was added to this emulsion, gold-sulfur sensitization was further performed using chloroauric acid and sodium thiosulfate, and a gelatin hardener was added to prepare a coating solution. The Ag / gelatin volume ratio was 2/1.

In the silver halide photographic light-sensitive material layer 41 shown in FIG. 7B, a conductive fine line pattern is not yet formed. The photomask pattern for forming the conductive pattern of the upper electrode U-3 has a sensor electrode width rw of 5.5 mm, a dummy electrode width dpw of 1 mm, a sensor electrode length of 200 mm, and a sensor electrode mesh conductivity. The width of the conductive thin line is 6 μm, the mesh lattice length is 250 μm, the inclination angle of the mesh thin line with the X axis is 45 °, and the width of the non-conductive boundary area (disconnection) between the sensor electrode and the dummy electrode is random The average value is 50 μm (maximum width is 75 μm, minimum value is 25 μm, the ratio between the standard deviation of width and the average value of width is 0.35), and 20 electrodes are formed on an A4 size PET sheet. Pattern.
A photomask having this pattern is brought into close contact with the photosensitive material 41 shown in FIG. 7 (b), and surface exposure is performed using parallel light using a high-pressure mercury lamp as a light source. The sample (FIG.7 (c)) which has was created. This sample was subjected to the following development processing to obtain an upper electrode U-3 in which sensor electrodes having a conductive thin wire structure were arranged. In the development process, an aggregate of developed silver is formed with the latent image in the emulsion formed in the exposed portion as a nucleus, and becomes a conductive thin line.

[Developer formulation] Water content is omitted per liter Hydroquinone 20 g
Sodium sulfite 50 g
Potassium carbonate 40 g
Ethylenediamine tetraacetic acid 2 g
Potassium bromide 3 g
Polyethylene glycol 2000 1 g
Potassium hydroxide 4 g
Adjust to pH 10.3

[Fixing solution formulation] Water content is omitted per liter Ammonium thiosulfate solution (75%) 300 ml
Ammonium sulfite monohydrate 25 g
1,3-diaminopropane tetraacetic acid 8 g
Acetic acid 5 g
Ammonia water (27%) 1 g
Adjust to pH 6.2

[Processing flow]
Processing machine: Fujifilm automatic processing machine (FG-710PTS)
Processing conditions: development is at 35 ° C. for 30 seconds,
Fixing is at 34 ° C for 23 seconds.
Washing with water is 20 seconds of running water (5 L / min).
The obtained sample was calendered to obtain an upper electrode U-3.

(Upper electrodes U-4 to U-8)
For the upper electrode U-1, except that the mesh grid side length is 250 μm, the upper electrode U-4 is the same as U-1, the mesh grid side length is 250 μm, and the fine mesh line width is The upper electrode U-5 is the same as U-1 except that the thickness is 6 μm, and the upper electrode U-5 is the same as U-1 except that the side length of the mesh lattice is 250 μm and the line width of the fine mesh wire is 8 μm. -6 was created.
Further, the upper electrode is similar to U-1 except that the upper electrode U-1 is an elongated rectangular band pattern having a non-conductive boundary area (disconnected portion) between the sensor electrode and the dummy electrode of 50 μm. U-7 was created.
Further, an upper electrode U-8 was prepared in the same manner as U-1 except that the inclination angle with respect to the X axis of the fine mesh wire was 0 ° with respect to the upper electrode U-1.

Example 1
Using the upper electrode created above, the brightness of the electrode sheet, the visibility of the screen when the touch panel was constructed (visibility, moire), and the resistance value were evaluated. The evaluation methods and ranks are as follows, and the results are shown in Table 1. The aperture ratio was obtained from this ratio by calculating the area of the grating from the gap between the electrodes and calculating the area of the opening from the width of the thin line.
(Brightness evaluation)
The transmittance of the conductive sheet was measured with a spectrophotometer. The transmittance was evaluated by a value at 550 nm.
X Evaluation The transmittance is less than 85% and the screen looks dark.
ΔEvaluation Brightness that does not matter when the transmittance is 85% or more and less than 90%.
○ Evaluation Brightness is 90% or more.
◎ Evaluation Brightness is sufficiently bright when the transmittance is 95% or more.
(Visibility)
Two upper electrodes are placed perpendicular to each other and attached to a liquid crystal display device, and the brightness of the image is changed. From the extreme case where a part of the pattern is sensed to the case where the shape is not recognized but the screen feels rough.
X Evaluation Shapes other than images are recognized. Or there is a feeling of line thickness or roughness on the screen.
ΔEvaluation You may feel line weight or roughness depending on the viewing direction. Reflection unevenness and linear gloss unevenness are observed.
○ Evaluation The screen looks uniform.
(Moire)
An A4 size upper electrode was attached to a liquid crystal display device so that the length direction of the electrode and the horizontal direction of the screen were parallel to each other, and it was examined whether moire could be detected by changing the brightness with a solid display.
X Evaluation Moire is easily observed.
ΔEvaluation Moire may be observed due to changes in screen brightness, coloring, and viewing angle.
○ Evaluation No moire is observed even when the conditions are changed.
(Resistance value)
The resistance values of 20 upper electrodes were directly read and the average value was described.

From the above results, it was confirmed that the mesh-like upper electrode of the present invention does not generate moire when the direction of the fine line of the mesh has an inclination angle with respect to the display screen. It was also confirmed that when the band-shaped boundary region separating the sensor electrode and the dummy electrode was not a clear rectangle and had a random width, the visibility could be improved and moire was less likely to occur.
Furthermore, it was found that it is effective to set the mesh opening efficiency to 90% or more in order to ensure the brightness of the screen.

In addition to the above, the following electrodes were prepared and their performance was examined.
In the upper electrode U-3, the average width of the non-conductive boundary region (disconnected portion) between the sensor electrode and the dummy electrode is 50 μm, the same as U-3, and the standard deviation of the width and the average value of the width are An upper electrode U-9a was produced in the same manner as U-3 except that the ratio was 0.14. When the visibility of this U-9a was examined, linear gloss unevenness was observed depending on the viewing direction, as in U-7.
On the other hand, the average value of the width of the boundary area (disconnected portion) is 50 μm, which is the same as U-3, and is the same as U-3 except that the ratio of the standard deviation of width to the average value of width is 0.20. Thus, an upper electrode U-9b was prepared. Similarly, the average value of the width is 50 μm, the same as U-3, the minimum value of the width is 10 μm, the maximum value is 100 μm, and the ratio of the standard deviation of the width to the average value of the width is 0.65. The upper electrode U-9c was prepared in the same manner as -3. In these electrodes U-9b, 9c and U-3, no uneven gloss was observed as in the electrode U-9a.
From these results, when the ratio between the standard deviation of width and the average value of width is less than 0.20, it is indistinguishable from the case of having a conventional rectangular boundary area, and the width is a random shape. In other words, it was found that the uneven glossiness cannot be improved.

Next, in the upper electrode U-2, the average width of the non-conductive boundary area (disconnected portion) between the sensor electrode and the dummy electrode is 20 μm, the same as U-2, and the standard deviation of the width and the average value of the width The upper electrode U-10 was prepared in the same manner as U-2, except that the ratio of the width and the minimum width was changed to 5 μm. In the upper electrode U-3, the average width of the non-conductive boundary area (disconnected portion) between the sensor electrode and the dummy electrode is 50 μm, the same as U-3, and the standard deviation of the width and the average value of the width The upper electrode U-9d was formed in the same manner as U-3 except that the ratio of the width was changed to 0.94 and the maximum width was changed to 140 μm.
When the insulating property between the adjacent electrodes of these electrodes U-10 and 9d was examined, it was found that the electrodes were conductive although rare. Even in the test under the same conditions, no insulation failure was observed at the electrodes U-2 and U-3.
From the above, it is desirable that the minimum value of the width of the non-conductive boundary region (disconnected portion) is 10 μm or more from the viewpoint of insulation. Further, it has been found that insulation failure may be caused even when the ratio of the standard deviation of the width to the average value of the width exceeds 100 μm and the ratio is more than 0.65.
From the above results, in order to improve the visibility, particularly to improve the unevenness of gloss and to ensure the insulation between the electrodes, the width of the non-conductive boundary region (disconnected portion) is in the range of 10 μm or more and 100 μm or less, It was confirmed that the average value was 15 μm or more and 70 μm or less, and the ratio between the standard deviation of the width and the average value of the width was preferably between 0.20 and 0.65.

Example 2
The upper electrodes U-1 and U-2 are electroplated with black tin to a thickness of 0.5 μm, and the black tin in portions other than the thin copper wires is removed by photolithography, and the upper electrodes U-11 and U-12 are removed. Created. When these electrodes U-1, U-2, U-11, and U-12 are observed at different angles, reflection of external light is observed depending on the angles of the electrodes U-1 and U-2 that are not blackened. On the other hand, no reflection was observed in the blackened U-11 and U-12. In addition, no reflection was observed in the electrode U-3.

Example 3
(Lower electrode L-1)
A bar electrode with a width of 6 mm and a length of 16 cm parallel to the short side of A4 size by photolithography using ITO film (sheet resistance 80Ω / □, formed on a PET film with a thickness of 175 μm) manufactured by Oike Industry 20 were formed with a gap of 1 mm, and this was used as the lower electrode L-1.
The lower electrode L-1 thus manufactured and the upper electrodes U-1 to U-8 were used to form the touch panel having the configuration shown in FIG. 1, and the touch panels TP-1 to TP-8 were created. A 100 μm PET film was used for the uppermost transparent material layer, and a commercially available adhesive was used.
Using a commercially available touch panel sensor IC having 20 or more X electrodes and Y electrodes (26 x 22 electrode lines from Synaptics, Inc.), a simple experimental device was created, and the above TP-1 to TP- 8 was connected to perform an operation test. As a result, there was no particular problem with the touch sensing from TP-1 to TP-8. On the other hand, the mesh portion of the upper electrode U-1 was formed of the ITO film, the dummy electrode was removed, and the upper electrode U-9 was formed as a 1 mm gap. The touch panel TP-9 (upper and lower ITO electrodes) using U-9 as the upper electrode had unstable touch sensing. Even when the width of the upper electrode was 12 mm, the operation was unstable. Since the resistance value of the bar electrode when the width of the upper electrode is 12 mm is about 1300Ω, it is considered that the unstable operation is caused by the small opening degree of the upper electrode without much difference from the resistance value of the upper electrode U-3. It was found that the aperture affects not only the brightness of the screen but also the sensitivity of touch detection.

10 Touch panel.
11 Upper electrode layer having a plurality of sensor electrodes.
12 A lower electrode layer having a plurality of sensor electrodes.
15 A transparent substrate layer that also serves as an insulating layer.
16 A transparent material layer constituting the touch surface.
17 Transparent substrate layer.
18 A transparent substrate layer also serving as electrode protection.
19 An adhesive layer that also serves as an insulating layer.
20 Range of touch surface.
21 Upper electrode forming layer 31 Mesh-like upper sensor electrode 32 Upper electrode coating layer 33 Mesh-like upper sensor electrode coating layer 41 Coating layer of silver halide photographic light-sensitive material (unphotosensitized)
42 Coated layer 43 of silver halide photographic light-sensitive material after pattern exposure The exposed portion 44 of the coated layer of silver halide photographic light-sensitive material 45 The portion where the exposed portion becomes developed silver by development and fixing processing 45 The emulsion is formed by development and fixing processing Unexposed portion C that has been removed and made transparent This represents the center line between two adjacent electrodes.
cb A non-conductive boundary region between the sensor electrodes of the lower electrode layer.
cd Indicates the width of the non-conductive boundary region between the sensor electrodes of the lower electrode layer.
cj Indicates the sensor electrode number of the lower electrode layer.
cm Indicates the intersection of the center line C and the conductive thin wire rm.
cp This represents the intersection before the crossing of the thin conductive wires.
cw represents the electrode width of the sensor electrode of the lower electrode layer.
Dl represents the length of the disconnection removal portion on the electrode ri side on the thin conductive wire rm.
Dm represents the length of the disconnection removal portion on the conductive thin wire rm.
Dm1 represents the distance between the break starting point Xm1 and cm on the conductive thin wire rm.
Dm2 represents the length of the disconnection removal portion on the conductive thin wire rm, that is, the distance between the disconnection start point Xm1 and the disconnection end point Xm2.
Dr represents the length of the disconnection removal portion on the electrode r-i + 1 side on the conductive thin wire rm.
dp-i Indicates the number of the dummy electrode.
dpw Indicates the width of the dummy electrode.
ET electrode terminal rb Indicates a non-conductive boundary region between the electrodes of the sensor electrode of the upper electrode layer.
rd Indicates the width of the non-conductive boundary region between the sensor electrodes of the upper electrode layer.
rd (m) represents the width of the boundary area at the intersection cm between the center line C between the electrodes and the conductive thin wire rm.
rdmax represents the maximum width of the non-conductive boundary region.
rdmin represents the minimum width of the non-conductive boundary region.
r-i Indicates the sensor electrode number of the upper electrode layer.
rm A mesh-like conductive fine wire of the sensor electrode of the upper electrode layer is shown.
rw Indicates the electrode width of the sensor electrode of the upper electrode layer.
Xm1 represents the starting point of disconnection on the thin conductive wire rm.
Xm2 represents the end point of disconnection on the thin conductive wire rm.
θ Indicates the angle formed by the fine mesh wire of the sensor electrode of the upper electrode layer and the electrode arrangement direction.

Claims (12)

At least a transparent material layer constituting the touch surface, an upper electrode layer having a plurality of sensor electrodes, an insulating layer, a lower electrode layer having a plurality of sensor electrodes and arranged orthogonal to the arrangement direction of the upper electrode, one or more transparent layers A capacitive touch panel having a multilayer structure including a base layer, wherein the sensor electrode constituting the upper electrode layer has a mesh shape made of a grid of conductive thin wires, and the direction of the fine wires of the grid is the direction of the sensor electrode It has an inclination angle of 30 ° or more and 60 ° or less with respect to the arrangement direction ,
The upper electrode has a non-conductive belt-like boundary region formed between adjacent sensor electrodes of the plurality of sensor electrodes constituting the electrode, and the non-conductive belt-like boundary region breaks the mesh-like conductive thin wire A capacitive touch panel that is formed by removing the width of the belt-like boundary region and randomly changes in the extending direction of the sensor electrode . 2. The capacitive touch panel according to claim 1, wherein an average value of the width of the belt-like boundary region is 15 μm or more and 70 μm or less. 3. The capacitive touch panel according to claim 1 , wherein a maximum value rdmax of the width of the belt-like boundary region is 100 μm or less, and a minimum value rdmin of the width is 10 μm or more. (Mean standard deviation / widths) the average value of the ratio of the standard deviation and the width of the width of the belt-shaped boundary region is 0.20 or more, according claim 1, characterized in that it is 0.65 or less Item 4. The capacitive touch panel according to any one of items 3 to 4. The capacitive touch panel according to any one of claims 1 to 4 , wherein a width of the mesh-like conductive thin wire of the upper sensor electrode is 0.5 µm or more and 10 µm or less. Mesh-shaped conductive thin line of the upper sensor electrode, claim 1, characterized in that it comprises a blackening layer formed on the layer and the layer of metal or alloy according to any one of claims 5 Capacitive touch panel. Capacitive touch panel according to 請 Motomeko 6 you, wherein the thickness of the metal layer or alloy layer of the mesh-shaped electroconductive thin line of the upper sensor electrode is 0.1μm or more 3μm or less. The capacitive touch panel according to claim 6 or 7 , wherein the blackened layer has a thickness of 0.1 µm to 3 µm.   9. The capacitive touch panel according to claim 1, wherein the width of each of the plurality of sensor electrodes constituting the upper electrode is 3 mm or more and 7 mm or less.   The capacitive touch panel according to any one of claims 1 to 9, wherein each electrode material of the plurality of sensor electrodes constituting the lower electrode is ITO.   The sensor electrode which comprises an upper electrode is arrange | positioned so that it may become parallel to a long side part, when the display part shape of this electrostatic capacitance type touch panel is represented by a long side and a short side. Item 11. The capacitive touch panel according to any one of Item 10. In the manufacturing method for a touch panel according to claims 6 to any one of claims 8, the mesh Joshirubeden of the upper sensor electrode having the blackening layer formed on the metal or alloy layer and on the layer A method for manufacturing a touch panel, characterized by forming a fine thin wire by the following steps.
Forming the metal layer or alloy layer on a transparent substrate,
Forming an electrode pattern on the metal layer or alloy layer,
Forming a blackened layer on the metal layer or alloy layer,
Removing the blackened layer in a portion other than the electrode pattern.

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