JP2012053644A - Conductive sheet, method for using conductive sheet and capacitance system touch panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductive sheet which is suitable to be used for, for example, a projection type capacitance system touch panel for lowering the resistance of a transparent conductive pattern formed on a substrate, and for improving visibility, and a method of using the conductive sheet.SOLUTION: A conductive sheet includes: a transparent substrate; a first conductive part formed on one main surface of the transparent substrate; and a second conductive part brought into contact with the other main surface of the transparent substrate. The first and second conductive parts respectively includes first and second thin line conductive patterns having a conductive thin line part and capacitance sensing parts formed on the thin line at a prescribed interval. The first and second thin line conductive patterns are arranged so as to cross each other when the conductive sheet is seen in a perspective view; the first and second thin line conductive patterns are substantially linear and the line width a of the thin line part is ranging from 0.1 to 25 μm; and the first and second capacitance sensing parts are not opened.

Description

  The present invention relates to a conductive sheet, a method of using the conductive sheet, and a capacitive touch panel, and more particularly to a conductive sheet suitable for use in a projected capacitive touch panel, a method of using the conductive sheet, 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 type has a simple structure, but cannot detect two or more contacts (multi-touch) 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, and more specifically, a plurality of electrodes in which a plurality of electrodes arranged in the vertical direction are connected in series. 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, a capacitive input device described in Patent Document 1 can be cited.
Furthermore, as another prior art of the projected capacitive touch panel, for example, a touch switch described in Patent Document 2 can be cited. As shown in FIG. 7A of Patent Document 2, the touch switch includes a first auxiliary line (24b) formed between the first electrodes (14b) on one surface of the substrate, and 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 A plurality of lattice shapes with uniform line intervals are formed by the lines, the conductor lines of the second electrode, and the second auxiliary lines.

JP 2008-310551 A International Publication No. 2010/013679

  However, since the capacitance-type input device described in Patent Document 1 forms the first electrode group and the second electrode group on one main surface of the substrate, the first electrode group, the second electrode group, Therefore, there is a problem that the detection accuracy of the position of the fingertip is inferior. Further, for example, the second electrode group is formed on the connection portion of the electrodes constituting the first electrode group via an insulating layer so that the portion (intersection) where the first electrode group and the second electrode group intersect is not short-circuited. As a result, each intersection is formed thick locally, and when the touch panel surface is viewed, each intersection is displayed as a spot (black spot). There is also a problem that the visibility is remarkably deteriorated. In addition, since an insulating layer and a mask pattern for forming a connection portion on the insulating layer are required, there is a problem that the manufacturing process becomes complicated and the manufacturing cost increases. Further, the electrode is composed of two electrode films sandwiching an insulating layer, and it is necessary to provide a short-circuit electrode film by a contact hole or the like, which causes a problem in productivity.

Therefore, it is conceivable to form the first electrode group on one main surface of the transparent substrate and form the second electrode group on the other main surface of the transparent substrate as in Patent Document 2 described above.
However, in Patent Document 2, when the first electrode and the first auxiliary line are formed on one surface of the substrate and the second electrode and the second auxiliary line are formed on the other surface of the substrate, due to manufacturing variations (film formation variations). The lattice shape does not become uniform, and even if there is a slight shift, the first auxiliary line and the straight line portion of the second electrode overlap, or the second auxiliary line and the straight line portion of the second electrode overlap. Become. If it does so, the width | variety of the part which the linear parts overlapped will become large (line-thickness), and, thereby, the position of a 1st electrode or a 2nd electrode will become conspicuous, and the problem that visibility deteriorates will arise.

As a constituent material of the electrode group, ITO (indium tin oxide thin film) is practically used although a printing method using conductive ink is known in the literature. There is no problem with ITO for small displays (those with a size of 5 inches or less such as mobile phones), but since ITO has a high electrical resistance (several tens of ohms / square), the current transfer speed between electrodes increases as the application size increases. There is a problem that the response speed (the time from when the fingertip is touched until the position is detected) is delayed. In particular, when used for a medium-sized or larger display (15 inches or more, particularly 20 inches or more), the detection sensitivity was insufficient. Therefore, it is possible to reduce the electrical resistance by increasing the thickness of ITO. However, when the thickness is increased, the yellow color is felt, the transmittance and the visibility are decreased, and the yield of the manufacturing process is decreased. Therefore, there is a problem that the manufacturing cost is increased.
Therefore, the present invention can be applied to a medium-sized or larger display by minimizing visibility by providing a capacitance sensing unit of a predetermined size to a thin wire pattern having a small electric resistance as a conducting wire. An object is to provide a transparent conductive film.

  The present invention has been made in consideration of such problems, and can reduce the resistance of the transparent conductive pattern formed on the substrate and improve the visibility. It is an object to provide a conductive sheet suitable for use in a capacitive touch panel and a method of using the conductive sheet.

  Another object of the present invention is to reduce the resistance of the transparent conductive pattern formed on the substrate and to improve the visibility. For example, a large projection capacitive touch panel can be used. An object of the present invention is to provide a touch panel that can be adapted to size.

[1] A conductive sheet having a transparent substrate, a first conductive portion formed on one main surface of the transparent substrate, and a second conductive portion in contact with the other main surface of the transparent substrate,
Each of the first conductive portions has two or more first fine wire conductive patterns extending in a first direction and arranged in a second direction orthogonal to the first direction,
Each of the second conductive portions has two or more second fine wire conductive patterns extending in a third direction and arranged in a fourth direction orthogonal to the third direction,
The first fine wire conductive pattern has a conductive fine wire portion and a first capacitance sensing portion formed at a predetermined interval on the thin wire,
The second thin wire conductive pattern has a conductive thin wire portion and a second capacitance sensing portion formed at a predetermined interval on the thin wire,
The first fine wire conductive pattern and the second fine wire conductive pattern are disposed so as to intersect when the conductive sheet is seen through, and the first and second fine wire conductive patterns are substantially linear. And the line width a of the thin line portion is 0.1 to 25 μm, and the first and second capacitance sensing portions are not open.

[2] The conductive sheet according to [1], wherein a line width a of the thin wire portions of the first and second thin wire conductive patterns of the first and second conductive portions is 1 to 15 μm.
[3] The conductive sheet according to [2], wherein the thickness of the first and second fine wire conductive patterns is 1 to 10 μm.
[4] The first and second capacitance sensing portions of the first and second thin wire conductive patterns contain 80% by mass or more of silver as a constituent component, and the area thereof is 400 to 6400 μm ^2. The conductive sheet according to [3], which is characterized.
[5] The first and second capacitance sensing parts of the first and second thin wire conductive patterns contain ITO or conductive fiber as a constituent component, and the area thereof is 400 to 18000 μm ^2. The conductive sheet according to [3], which is characterized.
[6] The thickness of the first and second capacitance sensing portions is substantially the same as the thickness of the thin line portions of the first and second thin wire conductive patterns. [4] or [5] ] The electrically conductive sheet of description.
[7] The first and second capacitance sensing portions of the first and second fine wire conductive patterns are arranged at intervals of 200 to 1500 μm in the thin wire portions of the first and second fine wire conductive patterns. The conductive sheet according to any one of [1] to [7], wherein
[8] The first and second capacitance sensing portions of the first and second thin wire conductive patterns are any one of a square, a rectangle, a diamond, a polygon, a circle, and an ellipse. [7] The conductive sheet according to [7].
[9] The conductive sheet according to [8], wherein the first and second capacitance sensing portions of the first and second fine wire conductive patterns are square or circular.
[10] The conductive sheet according to any one of [1] to [9], wherein the first and second thin wire conductive patterns of the first and second conductive portions are wavy.
[11] The first conductive portion has two or more first fine wire conductive patterns each extending in a first direction and arranged in a second direction orthogonal to the first direction, Each of the first thin wire conductive patterns is disposed at a distance of 200 to 1500 μm,
Each of the second conductive portions has two or more second thin wire conductive patterns extending in a third direction and arranged in a fourth direction orthogonal to the third direction. [2] The conductive sheet according to any one of [1] to [10], wherein the two fine wire conductive patterns are arranged at a distance of 200 to 1500 [mu] m.
[12] When the conductive sheet is seen through from the first conductive portion side, the first and second fine wire conductive patterns form a substantially square shape, and a capacitance is detected at the center of each side of the square shape. The conductive sheet according to [11], wherein a portion is formed.
[13] The distance between the adjacent first fine wire conductive patterns of the first conductive portion may be different from the distance between the adjacent second fine wire conductive patterns of the second conductive portion. The conductive sheet according to [11] or [12].
[14] The first conductive portion has a plurality of X electrodes arranged at intervals of 4 to 9 mm, the X electrodes are formed by combining a plurality of first fine wire conductive patterns, and the second conductive portion is Any one of [11] to [13], comprising a plurality of Y electrodes arranged at intervals of 4 to 9 mm, wherein the Y electrodes are formed by combining a plurality of second thin wire conductive patterns. The conductive sheet according to item.
[15] The plurality of first fine wire conductive patterns forming the X electrode of the first conductive portion have a connecting line connecting the first thin wire conductive patterns, and the plurality of first thin wire conductive patterns forming the Y electrode of the second conductive portion. The conductive sheet according to [14], wherein the second thin wire conductive pattern has a connecting line connecting the second thin wire conductive pattern.

[16] A conductive sheet having a transparent substrate, a first conductive portion formed on one main surface of the transparent substrate, and a second conductive portion in contact with the other main surface of the transparent substrate,
Each of the first conductive portions has two or more first fine wire conductive patterns extending in a first direction and arranged in a second direction orthogonal to the first direction,
Each of the second conductive portions has two or more second fine wire conductive patterns extending in a third direction and arranged in a fourth direction orthogonal to the third direction,
The first fine wire conductive pattern has a conductive fine wire portion and a first capacitance sensing portion formed at a predetermined interval on the thin wire,
The second thin wire conductive pattern has a conductive thin wire portion and a second capacitance sensing portion formed at a predetermined interval on the thin wire,
The first fine wire conductive pattern and the second fine wire conductive pattern are disposed so as to intersect when the conductive sheet is seen through, and the first and second fine wire conductive patterns are substantially linear. And the line width a of the thin line portion is 0.1 to 25 μm, and the first and second capacitance sensing units have openings.
[17] The line width a of the thin line portions of the first and second thin line conductive patterns described in Item 16 is 1 to 15 μm, and the thickness of the first and second thin line conductive patterns is 1 to 1 μm. A conductive sheet having a thickness of 10 μm.
[18] The first and second capacitance sensing units of the first and second thin wire conductive patterns described in [16] contain 80% by mass or more of silver as a constituent component and have an outer area of 10,000. A conductive sheet having a thickness of ˜500000 μm ² .
[19] The first and second capacitance sensing units of the first and second thin wire conductive patterns described in [16] contain ITO or conductive fiber as a constituent component and have an outer area of 10,000. A conductive sheet having a thickness of ˜500000 μm ² .
[20] The thickness of the first and second capacitance sensing units according to item 18 or 19 is substantially the same as the thickness of the thin line portions of the first and second thin line conductive patterns. Conductive sheet.
[21] The first and second capacitance sensing units of the first and second fine wire conductive patterns according to any one of Items 16 to 20, wherein the first and second fine wire conductive patterns are The conductive sheet is arranged at 300 to 1500 μm in the thin wire portion.
[22] The conductive sheet according to any one of items 16 to 21, wherein the first and second capacitance sensing units have a shape having a plurality of openings.
[23] In the first and second capacitance sensing units according to item 22, a plurality of similar shapes having different sizes are nested in the thin line portions of the first and second thin line patterns. A conductive sheet characterized by being a thing.
[24] The conductive sheet according to Item 23, wherein the plurality of similar nesting shapes having different sizes are any one of a circle, a square, a rhombus, an ellipse, a rectangle, and a polygon.
[25] A conductive sheet according to item 24, wherein a plurality of similar shapes different in size are nested in a rhombus or a circle.
[26] The conductive sheet according to item 24 or 25, wherein the similar shape at the center has a wider line width, and the outer similar shape has a smaller line width.
[27] In the nested similar shape according to item 24 or 25, the similar shape at the center is not opened, the similar shapes other than the center are opened, and the line width is larger as the outer similar shape is. A conductive sheet characterized by being thin.
[28] The conductive sheet according to any one of items 16 to 27, wherein the first and second fine wire conductive patterns are wavy.
[29] The first conductive portions according to any one of items 16 to 28, each extending in a first direction and arranged in a second direction orthogonal to the first direction. The first fine wire conductive pattern as described above, and the first fine wire conductive patterns are arranged with a distance of 300 to 1500 μm,
Each of the second conductive portions has two or more second thin wire conductive patterns extending in a third direction and arranged in a fourth direction orthogonal to the third direction. The two-wire conductive pattern is disposed at a distance of 300 to 1500 μm.
[30] When the conductive sheet according to item 29 is seen through from the first conductive portion side, the first and second fine wire conductive patterns form a substantially rectangular shape, and a central portion of each side of the rectangular shape. A conductive sheet, wherein a capacitance sensing part is formed.
[31] The distance between the adjacent first thin wire conductive patterns of the first conductive portion according to Item 29 or 30 is different from the distance between the adjacent second thin wire conductive patterns of the second conductive portion. A conductive sheet characterized in that it may be.
[32] The first conductive portion according to any one of items 29 to 31, including a plurality of X electrodes arranged at intervals of 4 to 9 mm, wherein the X electrodes are a plurality of first fine wire conductive patterns. The second conductive part has a plurality of Y electrodes arranged at intervals of 4 to 9 mm, and the Y electrode is formed by combining a plurality of second thin wire conductive patterns. Conductive sheet.
[33] The plurality of first thin wire conductive patterns forming the X electrode of the first conductive portion according to Item 32 have a connecting line connecting the first thin wire conductive patterns, and the Y of the second conductive portion. The plurality of second fine wire conductive patterns forming the electrode have a connecting line connecting the second fine wire conductive patterns.
[34] A conductive sheet having a transparent substrate, a first conductive portion formed on one main surface of the transparent substrate, and a second conductive portion in contact with the other main surface of the transparent substrate,
Each of the first conductive portions has two or more first fine wire conductive patterns extending in a first direction and arranged in a second direction orthogonal to the first direction,
Each of the second conductive portions has two or more second fine wire conductive patterns extending in a third direction and arranged in a fourth direction orthogonal to the third direction,
The first fine wire conductive pattern has a conductive fine wire portion and a first capacitance sensing portion formed at a predetermined interval on the thin wire,
The second thin wire conductive pattern has a conductive thin wire portion and a second capacitance sensing portion formed at a predetermined interval on the thin wire,
The first fine wire conductive pattern and the second fine wire conductive pattern are disposed so as to intersect when the conductive sheet is seen through, and the first and second fine wire conductive patterns are substantially linear. And the line width a of the thin line portion is 0.1 to 25 μm, and the first and second capacitance sensing portions have a fine mesh structure.
[35] In the conductive sheet according to any one of items 1 to 35, after forming the first conductive portion on the first transparent substrate and forming the second conductive portion on the second transparent substrate, A conductive sheet formed by bonding a surface of a first transparent substrate on which a conductive portion is not formed and a second conductive portion.
[36] The conductive sheet according to any one of items 1 to 35 is formed on the surface of the first transparent substrate on which the conductive portion is not formed after the first conductive portion is formed on the first transparent substrate. A conductive sheet comprising a second conductive portion.
[37] A conductive sheet, wherein a protective layer is provided on at least one of the surfaces of the conductive sheet according to item 35 or 36 that is not in contact with the transparent substrate of the first and second conductive portions.
[38] A capacitive touch panel comprising the conductive sheet according to any one of items 35 to 37.
[39] An image display device comprising the capacitive touch panel according to [38], wherein the first and second capacitance sensing units of the first and second conductive units are displayed on the image display device. An image display device, characterized in that the image display device is arranged at a substantially central part of the pixels of the part.

  As described above, according to the conductive sheet and the method for using the conductive sheet according to the present invention, the resistance of the transparent conductive pattern formed on the transparent substrate can be reduced, and the visibility can be improved. For example, it is suitable for use in a projected capacitive touch panel.

In addition, the touch panel according to the present invention can reduce the resistance of the transparent conductive pattern formed on the substrate and can also improve the visibility. For example, the large size of the projected capacitive touch panel It can be made to correspond.
In particular, when the silver salt type conductive film or the printing type conductive film according to the present invention is used, it is possible to reduce the electric resistance of the capacitance detection unit, so that the capacitance detection unit using ITO. It is no longer necessary to use a large pattern like the diamond pattern.
In addition, since the detection position can be detected with a sharp waveform, it is not necessary to perform position correction with a complicated algorithm. In particular, as in the conductive sheet of the second aspect of the present invention, when the capacitance detection unit is configured with a similar nest and the line width of the lattice near the center is increased, the position detection capability near the center increases, The position correction by a complicated algorithm can be eliminated.

(A) It is sectional drawing of the electrically conductive sheet of this invention. (B) It is sectional drawing of another electroconductive sheet of this invention. It is a top view of the 1st electroconductive part of this invention. It is a top view of the 2nd electroconductive part of this invention. It is a top view which shows a thin wire | line pattern when the conductive sheet of FIG. 1a is seen through from the 1st electroconductive part 12A side. (A) Shows a square lattice pattern, which is a simplified perspective view of FIG. 2c. (B) A rectangular grid pattern, which is a simplified perspective view of FIG. 2c. 4 shows variations of the square lattice pattern of FIG. 4 shows another variation of the square lattice pattern of FIG. An example of an X electrode pattern. However, the display of the capacitance sensing unit of the thin line pattern is omitted. An example of a Y electrode pattern. However, the display of the capacitance sensing unit of the thin line pattern is omitted. FIG. 6 is a partial perspective view of a similar nested electrostatic capacity sensing unit (square). FIG. 6 is a partial perspective view of a similar nested electrostatic capacity sensing unit (diamond). FIG. 6 is a partial perspective view of a similar nested nested capacitance sensing unit (circular). The illustration of the figure which changed the line width of the square of the electrostatic capacitance detection part of FIG. The illustration of the figure which changed the line | wire width of the rhombus of the electrostatic capacitance sensing part of FIG. The illustration of the figure which changed the line | wire width of the circle | round | yen of the electrostatic capacitance detection part of FIG. The partial perspective view of a mesh-shaped electrostatic capacitance sensing part (square diamond mesh). The figure which added the dummy electrode and the electrode leader line connection part to FIG. The figure which added the dummy electrode and the electrode leader line connection part to FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a conductive sheet, a method for using a conductive sheet, and a touch panel according to 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.

[First invention]
As shown in FIG. 1A, the conductive sheet according to the first aspect of the present invention (hereinafter referred to as the conductive sheet 10) includes a first conductive portion 12A provided on one main surface of the transparent substrate 11, And a second conductive portion 12B provided on the other main surface of the transparent substrate (also referred to as a substrate) 11.
As shown in FIG. 1B, the second first conductive portions 12A and 12B may be laminated after being provided on separate transparent substrates.
FIG. 2A is a diagram illustrating the first conductive portion 12A. The first conductive portions each extend in a first direction (also referred to as an X direction) and are orthogonal to the first direction. 2 has two or more first fine wire conductive patterns (13Ai in FIG. 2A) arranged in the second direction, and FIG. 2B is a diagram for explaining the second conductive portion 12B. The second conductive portions each extend in a third direction (also referred to as a Y direction) and are arranged in a fourth direction orthogonal to the third direction. 13Bj) of FIG. 2B.
The first fine wire conductive pattern 13A includes a conductive fine wire portion 14A that plays the role of a conducting wire and a first capacitance sensing portion 15A formed on the fine wire at a predetermined interval.
The second thin wire conductive pattern 13B includes a conductive thin wire portion 14B that serves as a conductive wire and a second capacitance sensing portion 15B formed on the thin wire at a predetermined interval. The sensing portions 15A and 15B of the conductive sheet according to the first aspect of the present invention have a shape without opening (also referred to as a solid).

The first and second fine line conductive patterns 13A and 13B are substantially linear, and the line width of the fine line portion is different from the first and second fine line conductive patterns 13A and 13B. However, the line width a of the thin line portion is preferably 0.1 to 25 μm, more preferably 1 to 20 μm, still more preferably 1 to 15 μm, and particularly preferably 1 to 10 μm. When used for a large screen of 20 inches or more, 3 to 15 μm is particularly preferable.
Furthermore, 1-10 micrometers is preferable and, as for the thickness of said 1st and 2nd thin wire | line conductive pattern, 1-5 micrometers is more preferable.
If the above-mentioned line width and thickness are less than the respective lower limit values, the electrical resistance of the thin line portion increases, so that there is a high possibility that it takes time for signal processing or detection failure. On the other hand, when the above upper limit values are exceeded, the aperture ratio is lowered, so that the screen becomes dark and the electrodes are easily visible.

The areas of the first and second capacitance sensing units may be different between 15A and 15B, but are usually the same size. The area of the sensing portion varies depending on the material constituting the sensing portion, and is preferably 400 to 6400 μm ^{2 in} the case of a material containing 80% by mass or more of silver, and 400 to 400 in the case of a light-transmitting material such as ITO. 18000 μm ² is preferred. When the area of the sensing unit is less than the lower limit, the detection sensitivity when touched is lowered, and when the area exceeds the upper limit, the sensing unit is easily visible and the screen is difficult to see. In addition, when it sees through, a clearance gap may be made between the 1st and 2nd electrostatic capacitance sensing parts which adjoin. In order to minimize this gap and to ensure uniform visibility, a dummy pattern may be provided electrically apart from the first and second capacitance sensing units.

  FIG. 2c is a plan view showing a conductive fine wire pattern when the conductive sheet of FIG. 1A is seen through from the first conductive portion 12A side, and the first fine wire conductive pattern 13A and the second thin wire conductive property are shown. It is arranged so as to intersect with the pattern 13B. In FIG. 2c, the crossing angle is approximately 90 degrees, but may be an angle other than 90 degrees as necessary for association with the pixels of the image display device. In the present invention, the term “intersection” and the terms “orthogonal” and “perpendicular” have the general meaning of these terms, but the elements that are intersected, orthogonal, or perpendicular are different. Because it is on the surface, it does not actually intersect. The term “intersection point” is also a virtual intersection point seen through. Further, D in FIG. 2c represents a virtual lattice formed by the first fine wire conductive pattern 13Ai and the second fine wire conductive pattern 13Bj.

2c is a virtual lattice because the first direction (X direction) of the first conductive part of FIG. 2a and the third direction (Y direction) of the second conductive part of FIG. Is a square lattice, but in the present invention, it is not necessary to be a square lattice as outlined in FIG. 3 (a), and one pattern may be a zigzag pattern as shown in FIG. Both patterns may be zigzag patterns (not shown) or may be wavy.
Furthermore, as shown in FIG. 5, adjacent fine lines of 13A fine lines are not in a parallel relationship, and adjacent fine lines of 13B fine lines are not in a parallel relationship, and the shape of the formed lattice is shifted from a square. It may be a shape. Furthermore, a rhombus lattice or a rectangular lattice may be used. Due to the deviation from the square shape and the formation of the inclination, it is possible to prevent unevenness such as optical interference due to the electrode lattice and the lattice of the pixel forming portion of the image display portion, and moire due to interference between the electrode lattice itself.

Next, an embodiment for using the conductive sheet of the present invention as a touch panel will be described.
In order to use the conductive sheet of the present invention for a touch panel, a plurality of electrodes (referred to as X electrodes) drawn from the first conductive portion and a plurality of electrodes (referred to as Y electrodes) drawn from the second conductive portion are signal processing portions. To be able to connect to.
The pitch of the X electrode and the Y electrode connected to the signal processing unit is preferably 4 to 9 mm, and more preferably 5 to 7 mm in a capacitive touch panel that senses the presence or absence of a finger touch. If the pitch is less than the above lower limit value, the capacitance per electrode at the time of detection decreases, which may result in detection failure. On the other hand, if the pitch exceeds the upper limit value, fewer electrodes are touched. Therefore, the position detection accuracy may be reduced.

FIGS. 6a and 6b show the relationship between the respective thin wire conductive patterns of the first and second conductive portions and the electrodes, and each X, Y electrode connects a plurality of thin wire conductive patterns. In FIGS. 6a and 6b, five first thin wire conductive patterns 13A and 13B are connected to each other, but this is merely an example. The number of thin conductive patterns connected to the electrodes is required to increase the area of the sensing unit in the touch area, the brightness of the screen, and the requirement of clear visibility for quick touch detection and accuracy. It can be decided in consideration.
In the conductive sheet according to the first aspect of the present invention in which the sensing portions 15A and 15B have a shape with no opening (also referred to as solid), the pitch of the thin wire conductive pattern is preferably 200 to 1000 μm for both the X and Y electrodes, More preferably, it is -600 micrometers. The number of connections to the electrode is preferably 3 to 50, and more preferably 5 to 35. The electrode lead-out portions may be provided at both end portions as exemplified by La and Lb in FIG. 14 and may be used for confirming the resistance value of the conductive pattern when manufacturing the conductive sheet.
The pitch between the electrodes of the X and Y electrodes and the pitch of the thin wire conductive patterns (13A and 13B) may be the same for the X and Y electrodes. However, the pixel aspect ratio and pitch of the image display device including the touch panel of the present invention may be used. It is preferable to adjust by the pitch of the X and Y electrodes, the crossing angle, and the shape of the virtual lattice so that it can cope.

Furthermore, in order to prepare for a decrease in capacitance sensing ability due to unexpected disconnection of the thin conductive pattern, a connecting line (20A and 20B shown in FIGS. 6a and 6b) for appropriately connecting the thin lines in the electrodes is formed. Also good. The line width and thickness of the connecting line may be the same as or different from the thin line.
Further, in order to prevent the position detection accuracy from being lowered due to the parasitic capacitance between the thin wire conductive patterns, the thin wire conductive patterns DX and DY (FIG. 14) that are not coupled to the touch sensing electrodes may be formed. good. DX and DY may be grounded, or may be used for resistance measurement after the electrodes are formed.

Next, the first and second capacitance sensing units in the conductive sheet of the first invention will be described.
The shape of the capacitance detection unit of the first aspect of the present invention may be any of a square, a rectangle, a rhombus, a polygon, a circle, and an ellipse, and is preferably a substantially square or a circle. In FIG. 2, a square capacitance sensing unit is shown as an example.
The capacitance sensing unit of the present invention is formed at a predetermined interval in the thin line portions of the first and second thin line conductive patterns. As shown in FIG. 3A, the capacitance sensing unit is usually formed to be disposed at the center of one side of the virtual lattice, and the distance between the sensing units is 200 to 1500 μm. It is preferable that the thickness is 300 to 600 μm. When increasing the capacitance to be sensed, a plurality of sensing units can be arranged near the center of one side of the virtual lattice, as shown in FIG.

The capacitance sensing portion of the present invention preferably has an area of 400 to 18000 μm ² . If less than 400 [mu] m ^2, may become undetectable because the capacitance is reduced, a possibility arises which is visible to exceed 18000μm ^2.
As a constituent component of the thin wire conductive pattern including the capacitance sensing portion of the present invention, it can be formed using a material containing 80% by mass or more of silver, or a material containing ITO or conductive fiber. . In particular, since the material containing silver 80% by mass or more has a high conductivity, a small area of ITO can form a desired sensing portion, the area 400～6400Myuemu ^2, more preferably be a 625～3600Myuemu ² .

[Second invention]
As shown in FIG. 1A, the conductive sheet according to the second aspect of the present invention (hereinafter referred to as the conductive sheet 10) includes a first conductive portion 12A provided on one main surface of the transparent substrate 11, The second conductive portion 12B is provided on the other main surface of the transparent substrate 11.
As shown in FIG. 1B, the second first conductive portions 12A and 12B may be laminated after being provided on separate transparent substrates.
FIG. 2a is a diagram for explaining the first conductive portion 12A. Each first conductive portion extends in a first direction (also referred to as X direction) and is perpendicular to the first direction. FIG. 2B is a diagram illustrating the second conductive portion 12B, and the second conductive portions are respectively connected to the first conductive portions 12A and 13B in FIG. 2A. Two or more second thin wire conductive patterns (13Bj in FIG. 2b) extending in three directions (also referred to as Y direction) and arranged in a fourth direction orthogonal to the third direction Yes.
The first fine wire conductive pattern 13A includes a conductive fine wire portion 14A that plays the role of a conducting wire and a first capacitance sensing portion 15A formed on the fine wire at a predetermined interval.
The second thin wire conductive pattern 13B includes a conductive thin wire portion 14B that serves as a conductive wire and a second capacitance sensing portion 15B formed on the thin wire at a predetermined interval. The conductive sheet sensing portions 15A and 15B according to the second aspect of the present invention have a nested shape (also simply referred to as “nested”) having an opening. The nested structure will be described below with reference to FIGS.

The first and second fine line conductive patterns 13A and 13B are substantially linear, and the line width of the fine line portion is different from the first and second fine line conductive patterns 13A and 13B. However, it is usually the same line width, and the line width a of the thin line portion is preferably 0.1 to 25 μm, more preferably 1 to 20 μm, still more preferably 1 to 15 μm, and particularly preferably 1 to 10 μm.
Furthermore, 1-10 micrometers is preferable and, as for the thickness of said 1st and 2nd thin wire | line conductive pattern, 1-5 micrometers is more preferable.
If the above-mentioned line width and thickness are less than the respective lower limit values, the electrical resistance of the thin line portion increases, so the possibility of detection failure increases. On the other hand, when each of the above upper limit values is exceeded, the aperture ratio is lowered, so that the screen becomes dark and the electrodes are easily visually recognized.

The areas of the first and second capacitance sensing units may be different between 15A and 15B, but are usually the same size. The capacitance sensing unit of the second invention of the present invention is a nested shape having an opening, and the area depends on the size of the virtual lattice, but the outer area is preferably in the range of 10,000 to 500,000 μm ² , and 40000 to 400,000 100,000 μm. A range of ² is more preferred. When the area of the sensing unit is less than the lower limit, the detection sensitivity when touched is lowered, and when the area exceeds the upper limit, the sensing unit is easily visible and the screen is difficult to see.

  FIG. 2c is a plan view showing a conductive fine wire pattern when the conductive sheet of FIG. 1A is seen through from the first conductive portion 12A side, and the first fine wire conductive pattern 13A and the second thin wire conductive property are shown. It is arranged so as to intersect with the pattern 13B. In FIG. 2c, the crossing angle is approximately 90 degrees, but may be an angle other than 90 degrees as necessary for association with the pixels of the image display device. In the present invention, the term “intersection” and the terms “orthogonal” and “perpendicular” have the general meaning of these terms, but the elements that are intersected, orthogonal, or perpendicular are different. Because it is on the surface, it does not actually intersect. The term “intersection point” is also a virtual intersection point seen through. D in FIG. 2c represents a virtual lattice formed by the first fine wire conductive pattern 13Ai and the second fine wire conductive pattern 13Bj.

2c is a virtual lattice because the first direction (X direction) of the first conductive part of FIG. 2a and the third direction (Y direction) of the second conductive part of FIG. Is a square lattice, but in the present invention, it is not necessary to be a square lattice as outlined in FIG. 3 (a), and one pattern may be a zigzag pattern as shown in FIG. Both patterns may be zigzag patterns (not shown) or may be wavy.
Furthermore, as shown in FIG. 5, adjacent fine lines of 13A fine lines are not in a parallel relationship, and adjacent fine lines of 13B fine lines are not in a parallel relationship, and the shape of the formed lattice is shifted from a square. It may be a shape. Furthermore, a rhombus lattice or a rectangular lattice may be used. Due to the deviation from the square shape and the formation of the inclination, it is possible to prevent unevenness such as optical interference due to the electrode lattice and the lattice of the pixel forming portion of the image display portion, and moire due to interference between the electrode lattice itself.

Next, an embodiment for using the conductive sheet of the present invention as a touch panel will be described.
In order to use the conductive sheet of the present invention for a touch panel, a plurality of electrodes (referred to as X electrodes) drawn from the first conductive portion and a plurality of electrodes (referred to as Y electrodes) drawn from the second conductive portion are signal processing portions. To be able to connect to.
The pitch of the X electrode and the Y electrode connected to the signal processing unit is preferably 4 to 9 mm, and more preferably 5 to 7 mm in a capacitive touch panel that senses the presence or absence of a finger touch. If the pitch is less than the above lower limit value, the capacitance per electrode at the time of detection decreases, which may result in detection failure. On the other hand, if the pitch exceeds the upper limit value, fewer electrodes are touched. Therefore, the position detection accuracy may be reduced.

FIGS. 6a and 6b show the relationship between the respective thin wire conductive patterns of the first and second conductive portions and the electrodes, and each X, Y electrode connects a plurality of thin wire conductive patterns. In FIGS. 6a and 6b, five first thin wire conductive patterns 13A and 13B are connected to each other, but this is merely an example. The number of thin conductive patterns connected to the electrodes is required to increase the area of the sensing unit in the touch area, the brightness of the screen, and the requirement of clear visibility for quick touch detection and accuracy. It can be decided in consideration.
In the conductive sheet according to the second aspect of the present invention in which the sensing portions 15A and 15B have a nested shape (also referred to as nested) having an opening, the pitch of the thin wire conductive pattern is 200 to 2000 μm for both the X and Y electrodes. Preferably, it is 300-1500 micrometers. The number of connections to the electrode is preferably from 3 to 30, and more preferably from 4 to 20. The sensing units 15A and 15B have a nested shape having an opening, and the opening ratio is preferably 50% or more.
The pitch between the electrodes of the X and Y electrodes and the pitch of the thin wire conductive patterns (13A and 13B) may be the same for the X and Y electrodes. However, the pixel aspect ratio and pitch of the image display device including the touch panel of the present invention may be used. It is preferable to adjust by the pitch of the X and Y electrodes, the crossing angle, and the shape of the virtual lattice so that it can cope.

Furthermore, in order to prepare for a decrease in capacitance sensing ability due to unexpected disconnection of the thin conductive pattern, a connecting line (20A and 20B shown in FIGS. 6a and 6b) for appropriately connecting the thin lines in the electrodes is formed. Also good. The line width and thickness of the connecting line may be the same as or different from the thin line.
Furthermore, in order to prevent the position detection system from deteriorating due to the parasitic capacitance between the thin wire conductive patterns, the thin wire conductive patterns DX and DY (FIGS. 14a and 14b) that are not coupled to the electrodes may be formed. . DX and DY may be grounded, or may be used for resistance measurement after the electrodes are formed.

Next, the first and second capacitance sensing units in the conductive sheet of the second invention will be described in detail.
The shape of the capacitance detection part of the second aspect of the present invention is a form in which a square, a rectangle, a rhombus, a polygon, a circle, and an ellipse are nested, and any of these shapes may be used. Nested, approximately diamond-shaped, and approximately circularly nested. 7, 8, and 9 exemplify capacitance sensing units having square nesting, diamond-shaped nesting, and circular nesting, respectively. 7, 8, and 9 show a state where four large and small similar shapes are nested, and each similar shape is connected to the thin wire portion (conductive wire) at two points. The nesting may be connected by a connecting wire different from the conducting wire.

  The number of similar shapes to be nested is preferably 2 to 10, more preferably 3 to 6. Moreover, the line width of each similar shape may be the same, and may be the same line width as a thin wire | line part. Furthermore, it is more preferable that the line width is wider as the inner shape of the insert is wider and the line width is narrower toward the outer side. By adopting such a shape, the sensing ability can be increased toward the center of the sensing unit. Furthermore, it is more preferable that the innermost similar shape of the nesting is an open shape, the outer shape is an open similar shape, and the line width is narrower toward the outer side. The square, rhombus, and circular sensing units are illustrated in FIGS. In more detail, taking FIG. 10 as an example, in FIG. 10, four squares are nested, and the center square 15A1 is not open, and the line width of the next largest square 15A2 located outside 15A1. Is the line width of three times the line width of the fine line part of the fine line pattern, and the line width of the next largest square 15A3 is twice the line width of the fine line part of the fine line pattern and is the largest square 15A4 The line width is the same as the line width of the fine line portion of the fine line pattern. By adopting such a structure, the position sensing ability near the center of the capacitance sensing unit is increased, so that it is not necessary to correct the sensing position with a complicated algorithm.

  The capacitance sensing unit of the present invention is formed at a predetermined interval in the thin line portions of the first and second thin line conductive patterns. As shown in FIG. 3A, the capacitance sensing unit is usually formed to be disposed at the center of one side of the virtual lattice, and the distance between the sensing units is 200 to 2000 μm. It is preferable that it is 300 to 1500 μm.

The area of the capacitance sensing unit of the present invention is not limited as long as the capacitance detection units of the fine line patterns 13A and 13B constituting the two sides of the lattice do not overlap in the perspective views of FIGS. . However, the largest line width among the similar shapes is preferably 60 μm or less, and more preferably 40 μm or less in order to avoid visual recognition of the line.
The capacitance sensing unit of the present invention preferably has an outer area of 10,000 to 500,000 μm ² . If less than 10000 ^2, may become undetectable because the capacitance is reduced, a possibility arises which is visible to exceed 500000μm ^2. Here, the “outer shape” is an area of the shape formed by the outer side of the outermost nest in the nest of the present invention. For example, in the case of square nesting, the outermost shell has an inner side length of 200 μm and an outer side length of 220 μm (that is, the width of the conductive portion is 10 μm), it is 48400 μm ² .
As a constituent component of the thin wire conductive pattern including the capacitance sensing portion of the present invention, it can be formed using a material containing 80% by mass or more of silver, or a material containing ITO or conductive fiber. . In particular, since a material containing 80% by mass or more of silver has high conductivity, a desired sensing portion can be formed with a smaller area than ITO.

[Third Invention]
As shown in FIG. 1A, the conductive sheet according to the third aspect of the present invention (hereinafter referred to as the conductive sheet 10) includes a first conductive portion 12A provided on one main surface of the transparent substrate 11, and The second conductive portion 12B is provided on the other main surface of the transparent substrate 11.
As shown in FIG. 1B, the second first conductive portions 12A and 12B may be laminated after being provided on separate transparent substrates.
FIG. 2a is a diagram for explaining the first conductive portion 12A. Each first conductive portion extends in a first direction (also referred to as X direction) and is perpendicular to the first direction. FIG. 2B is a diagram illustrating the second conductive portion 12B, and the second conductive portions are respectively connected to the first conductive portions 12A and 13B in FIG. 2A. Two or more second thin wire conductive patterns (13Bj in FIG. 2b) extending in three directions (also referred to as Y direction) and arranged in a fourth direction orthogonal to the third direction Yes.
The first fine wire conductive pattern 13A includes a conductive fine wire portion 14A that plays the role of a conducting wire and a first capacitance sensing portion 15A formed on the fine wire at a predetermined interval.
The second thin wire conductive pattern 13B includes a conductive thin wire portion 14B that serves as a conductive wire and a second capacitance sensing portion 15B formed on the thin wire at a predetermined interval. The sensing parts 15A and 15B of the conductive sheet according to the third aspect of the present invention have a fine mesh structure.

  The shape of the first and second fine wire conductive patterns 13A and 13B, the line width, the thickness, and the shape of the first and second mesh-like electrostatic capacitance sensing parts are the diamond-shaped nesting of the second invention. Can be applied.

Next, an embodiment for using the conductive sheet of the present invention as a touch panel will be described.
In order to use the conductive sheet of the present invention for a touch panel, a plurality of electrodes (referred to as X electrodes) drawn from the first conductive portion and a plurality of electrodes (referred to as Y electrodes) drawn from the second conductive portion are signal processing portions. To be able to connect to.
The pitch of the X electrode and the Y electrode connected to the signal processing unit is preferably 4 to 9 mm, and more preferably 5 to 7 mm in a capacitive touch panel that senses the presence or absence of a finger touch. If the pitch is less than the above lower limit value, the capacitance of the electrode at the time of detection decreases, so the possibility of detection failure increases. On the other hand, if the upper limit is exceeded, the position detection accuracy may be reduced.

FIGS. 6a and 6b show the relationship between the respective thin wire conductive patterns of the first and second conductive portions and the electrodes, and each X, Y electrode connects a plurality of thin wire conductive patterns. In FIGS. 6a and 6b, five first thin wire conductive patterns 13A and 13B are connected to each other, but this is merely an example. The number of thin-wire conductive patterns to be connected is determined based on the requirement for increasing the area of the sensing unit in the touch area, the brightness of the screen, and the requirement for clear visibility for quick touch detection and accuracy. I can do it.
In the conductive sheet according to the third aspect of the present invention in which the sensing portions 15A and 15B are mesh-shaped with openings, the pitch of the thin wire conductive pattern is preferably 200 to 2000 μm for both the X and Y electrodes, and is 300 to 1500 μm. More preferably it is. The number of connections to the electrode is preferably from 3 to 30, and more preferably from 4 to 20. The sensing units 15A and 15B are preferably in a mesh shape with an aperture ratio of 50% or more.
The pitch between the electrodes of the X and Y electrodes and the pitch of the thin wire conductive patterns (13A and 13B) may be the same for the X and Y electrodes. However, the pixel aspect ratio and pitch of the image display device including the touch panel of the present invention may be used. It is preferable to adjust with X and Y electrodes so as to be able to cope.

Furthermore, in order to prepare for a decrease in capacitance sensing ability due to unexpected disconnection of the thin conductive pattern, a connecting line (20A and 20B shown in FIGS. 6a and 6b) for appropriately connecting the thin lines in the electrodes is formed. Also good. The line width and thickness of the connecting line are preferably the same as those of the thin line.
Furthermore, in order to prevent the position detection system from being lowered due to the parasitic capacitance between the thin wire conductive patterns, a thin wire conductive pattern (not shown) that is not coupled to the electrode may be formed.

Next, the first and second capacitance sensing units in the conductive sheet of the third aspect of the present invention will be described.
The external shape of the capacitance sensing unit of the third aspect of the present invention is a square, rectangular, rhombus, polygonal, circular, or elliptical shape, and the inside of these external shapes is a mesh shape with an opening. These external shapes may be any of the above-mentioned external shapes, and are preferably approximately square, approximately rhombus, and approximately circular. FIG. 13 illustrates a capacitance sensing unit that is a square rhombus mesh having a square rhombus outer shape. Two opposing vertices of the fine line forming the outer shape of the mesh are connected to the fine line portion of the fine line conductive pattern which is a conductive line.
The fine wire forming the mesh preferably has a width approximately equal to the width of the fine wire portion of the fine wire conductive pattern, which is a conductive wire, and further has an aspect in which the outer shape is narrowed from the central portion within a range not exceeding 50 μm. preferable.

  The capacitance sensing unit of the present invention is formed at a predetermined interval in the thin line portions of the first and second thin line conductive patterns. As shown in FIG. 13, the capacitance sensing unit is usually formed at the center of one side of the virtual lattice, and the distance between the sensing units is 200 to 2000 μm. Preferably, it is 300-1500 micrometers.

The fine wire forming the mesh can have a width approximately equal to the width of the fine wire portion of the fine wire conductive pattern which is a conductive wire.
The fine lines forming the mesh do not need to be formed with a uniform line width, and it is more preferable that the center part of the mesh is wider and the outer part is thinner. By adopting such a structure, the position sensing ability near the center of the capacitance sensing unit is increased, so that it is not necessary to correct the sensing position with a complicated algorithm. Specifically, the line width of the central portion of the mesh may be in a range not exceeding 50 μm, and the outer shape portion may have the same width as the width of the thin wire portion of the thin wire conductive pattern which is a conductive wire.

The area occupied by the outer shape of the capacitance sensing unit of the present invention is limited as long as the capacitance detection units of the thin wire conductive patterns 13A and 13B constituting the two sides of the lattice do not overlap in the perspective view of FIG. There is no.
The capacitance sensing unit of the present invention preferably has an outer area of 10,000 to 500,000 μm ² . If less than 10000 ^2, may become undetectable because the capacitance is reduced, a possibility arises which is visible to exceed 500000μm ^2.

  In FIG. 13, the mesh of the mesh-shaped electrostatic capacitance sensing unit is illustrated as a square of 5 5, but is 4 to 900 as long as the external area, aperture ratio, and thin line width constraints described above are satisfied. It can be formed in any number suitable for the outer shape within the range.

  As a constituent component of the thin wire conductive pattern including the capacitance sensing portion of the present invention, it can be formed using a material containing 80% by mass or more of silver, or a material containing ITO or conductive fiber. . In particular, since a material containing 80% by mass or more of silver has high conductivity, a desired sensing portion can be formed with a smaller area than ITO.

[Touch panel, image display device]
Next, a capacitive touch panel using the conductive sheet according to the first to third aspects of the present invention will be described.
The capacitive touch panel according to the present invention includes any one of the conductive sheets according to the first to third aspects of the present invention described above, and these conductive sheets are provided on one main surface of the transparent substrate. Several adjacent ones of the formed first thin line patterns are connected to form an X electrode terminal leading to the signal processing unit, and the plurality of first electrodes formed on the other main surface of the transparent substrate. Several adjacent two thin line patterns are connected to form a Y electrode terminal that communicates with the signal processing unit.

  The conductive sheet of the present invention is a conductive sheet in which a first conductive portion 12A and a second conductive portion 12B are formed on two surfaces of a transparent substrate 11, as illustrated in FIG. As illustrated in FIG. 1b, the first conductive portion 12A is formed on the first transparent substrate 11A, and the second conductive portion 12B is formed on the second transparent substrate 11B. A conductive sheet in which two members are bonded together as in 1 (b) may be used.

  The conductive sheet preferably has a protective film adjacent to the first conductive portion 12A in FIGS. 1A and 1B and the second conductive portion 12B in FIG. 1B. Furthermore, it is further preferable that an antireflection layer is provided on the touch surface so that an operator can easily recognize the screen, or a hard coat layer or an antifouling layer is provided to prevent scratches or dirt on the touch surface. The conductive sheet 10 of the present invention thus formed is used as a panel part of a touch panel, and the touch panel is used for various image display devices such as a mobile phone, a personal computer, and a television.

  When the touch panel is overlaid on the image display device, moire may occur on the screen, which may hinder image visibility. In particular, it tends to occur when the pixels of the image display device and the thin line pattern of the touch panel are parallel. Therefore, it is preferable that the extending direction of the fine line pattern of the conductive sheet of the present invention and the alignment direction of the pixels of the display device are arranged so as to be inclined and not in a parallel relationship. For example, the extending direction of the X electrode and the Y electrode in FIGS. 6a and 6b can be 45 degrees with respect to the direction of the pixel pattern of the display device.

  Moire may also occur in the conductive sheet itself, and this can be prevented by making the thin line pattern not parallel as shown in FIG. 4 or FIG.

  In the image display device including the capacitive touch panel according to the present invention, the above-described conductive sheet according to the present invention is configured such that the first and second capacitance sensing units are substantially center portions of pixels of the display unit of the image display device. It is preferable to arrange in. In many cases, the vertical and horizontal pitches of the pixels of the display unit of the image display device are different from each other in the vertical and horizontal directions. A method is used in which the pitch of the capacitance sensing portion of the electrode is set to a different pitch between the X electrode and the Y electrode in accordance with the pixel pattern, or the crossing angle in the extending direction of the X electrode and the Y electrode is appropriately adjusted. be able to.

Next, a method for manufacturing the conductive sheet 10 will be described.
As a method for producing the conductive sheet 10, for example, a photosensitive material provided with an emulsion layer containing a photosensitive silver halide salt on the first transparent substrate 11A and the second transparent substrate 11B is subjected to pattern exposure, and development processing is performed. By applying, a metal silver portion and a light transmissive portion may be formed in the exposed portion and the unexposed portion, respectively, to form the X electrode pattern of FIG. 6a and the Y electrode pattern of FIG. 6b. In addition, you may make it carry | support a conductive metal to a metal silver part by giving a physical development and / or a plating process to a metal silver part further.

  Alternatively, a copper foil layer and a photoresist film are formed in this order on the first transparent substrate 11A and the second transparent substrate 11B, respectively, and the photoresist film on the formed copper foil is exposed and developed to form a resist pattern. Then, the X and Y electrode patterns of FIG. 6 may be formed by etching the copper foil exposed from the resist pattern. Instead of the copper foil, a metal foil such as gold or a transparent oxide film such as ITO may be used.

  Alternatively, the X and Y electrode patterns may be formed by printing a paste containing metal fine particles and conductive fibers on the first transparent substrate 11A and the second transparent substrate 11B, respectively, as shown in FIG. Furthermore, metal plating may be performed on the X and Y electrode patterns. Screen printing or gravure printing is used for printing.

The structure of the conductive fiber may be a solid structure or a hollow structure. Here, the solid structure fiber may be referred to as a wire, and the hollow structure fiber may be referred to as a tube. A conductive fiber having an average minor axis length of 5 nm to 1,000 nm and an average major axis length of 1 μm to 100 μm may be referred to as “nanowire”. In addition, conductive fibers having an average minor axis length of 1 nm to 1,000 nm and an average major axis length of 0.1 μm to 1,000 μm and having a hollow structure may be referred to as “nanotubes”.
The material of the conductive fiber is not particularly limited as long as it has conductivity, and is preferably at least one of metal and carbon. Among these, the conductive fiber is a metal nanowire, It is preferably at least one of a metal nanotube and a carbon nanotube.

<< Metal nanowires >>
-Material-
There is no restriction | limiting in particular as a material of the said metal nanowire, According to the objective, it can select suitably, For example, the group which consists of a 4th period, a 5th period, and a 6th period of a long periodic table (IUPAC1991) At least one metal selected from the group 2, more preferably at least one metal selected from the group 2 to group 14, the group 2, the group 8, the group 9, the group 10, the group 11, At least one metal selected from Group 12, Group 13, and Group 14 is more preferable, and it is particularly preferable that it is included as a main component.

-Metal-
Examples of the metal include copper, silver, gold, platinum, palladium, nickel, tin, cobalt, rhodium, iridium, iron, ruthenium, osmium, manganese, molybdenum, tungsten, niobium, tantel, titanium, bismuth, antimony, and lead. Or alloys thereof. Among these, silver and an alloy with silver are preferable in terms of excellent conductivity.

−Average minor axis length diameter and average major axis length−
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, 15 nm to 35 nm is particularly preferable.
The average minor axis length of the metal nanowires was observed using 300 transmission metal microscopes (TEM; JEM-2000FX, JEM-2000FX), and the average value of the metal nanowires was determined from the average value. The average minor axis length was determined. In addition, the shortest axis length when the short axis of the metal nanowire is not circular is the shortest axis.
The average major axis length of the metal nanowire (sometimes referred to as “average length”) is preferably 2 μm or more, more preferably 2 μm to 40 μm, still more preferably 3 μm to 35 μm, 5 μm to 30 μm is particularly preferable.
The average major axis length of the metal nanowire is observed, for example, using a transmission electron microscope (TEM; JEM-2000FX, JEM-2000FX). The average major axis length was determined. In addition, when the said metal nanowire was bent, the circle | round | yen which makes it an arc was considered and the value calculated from the radius and curvature was made into the major axis length.
In the case of forming a conductive layer using conductive fibers, for example, JP2009-215594, JP2009-242880, JP2009-299162, JP2010-84173, JP2010-87105, JP2010. -86714 can be combined with the disclosed technology.

  Next, a method for manufacturing the conductive sheet 10 according to the present embodiment will be described focusing on a method for manufacturing a conductive pattern using a silver halide photographic light-sensitive material, which is a particularly preferable embodiment.

The manufacturing method of the conductive sheet 10 according to the present embodiment includes the following three modes depending on the photosensitive material and the type 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 resulting 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 techniques described in Japanese Patent Application Laid-Open Nos. 2004-184893, 2004-334077, and 2005-010752, and Japanese Patent Application Nos. 2004-244080 and 2004-085655 can be applied. it can.

  Here, the configuration of each layer of the first conductive sheet 10A and the second conductive sheet 10B according to the present embodiment will be described in detail below.

[First Transparent Base 11A, Second Transparent Base 11B]
Examples of the first transparent substrate 11A and the second transparent substrate 11B include a plastic film, a plastic plate, and a glass plate.

  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.

As the first transparent substrate 11A and the second transparent substrate 11B, 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 the like, preferably a plastic film or plastic plate having a melting point of about 290 ° C. or less, In particular, PET is preferable from the viewpoints of light transmittance and processability. Since the transparent conductive films such as the first conductive sheet 10A and the second conductive sheet 10B used for the first touch panel conductive sheet 10A and the second touch panel conductive sheet 10B are required to be transparent, the first transparent substrate The transparency of 11A and the second transparent substrate 11B is preferably high.

[Silver salt emulsion layer]
The silver salt emulsion layer serving as the conductive layer of the first conductive sheet 10A and the second conductive sheet 10B contains additives such as a solvent and a dye in addition to the silver salt and the binder.

  Examples of the silver salt used in the present embodiment include inorganic silver salts such as silver halide and organic silver salts such as silver acetate. In the present embodiment, it is preferable to use silver halide having excellent characteristics as an optical sensor.

  The coating silver amount (silver salt coating amount) of the silver salt emulsion layer is preferably 1 to 30 g / m @ 2, more preferably 1 to 25 g / m @ 2, and still more preferably 5 to 20 g / m @ 2 in terms of silver. By setting the coated silver amount within the above range, the conductive sheet after exposure and development processing can obtain a desired surface resistance.

  Examples of the binder used in the present embodiment include gelatin, polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), starch and other polysaccharides, cellulose and derivatives thereof, polyethylene oxide, polyvinyl amine, chitosan, polylysine, and polyacryl. Examples include acid, polyalginic acid, polyhyaluronic acid, carboxycellulose and the like. These have neutral, anionic, and cationic properties depending on the ionicity of the functional group.

  The content of the binder contained in the coating layer of the silver salt emulsion of the present embodiment is not particularly limited, and can be appropriately determined as long as dispersibility and adhesion can be exhibited. The content of the binder in the silver salt emulsion layer 16 is preferably 1/4 or more, and more preferably 1/2 or more in terms of a silver / binder volume ratio. The silver / binder volume ratio is preferably 100/1 or less, and more preferably 50/1 or less. The silver / binder volume ratio is more preferably 1/1 to 4/1. Most preferably, it is 1/1 to 3/1. By setting the silver / binder volume ratio in the silver salt emulsion layer within this range, even when the amount of coated silver is adjusted, variation in resistance value is suppressed, and the first touch panel conductive sheet 10A having a uniform surface resistance and the first The electrically conductive sheet 10B for 2 touch panels can be obtained. The silver / binder volume ratio is converted from the amount of silver halide / binder amount (weight ratio) of the raw material to the amount of silver / binder amount (weight ratio), and further the amount of silver / binder amount (weight ratio) is silver amount. / It can obtain | require by converting into binder amount (volume ratio).

<Solvent>
The solvent used for forming the coating layer of the silver salt emulsion is not particularly limited. For example, water, organic solvents (for example, alcohols such as methanol, ketones such as acetone, amides such as formamide, Sulfoxides such as dimethyl sulfoxide, esters such as ethyl acetate, ethers, etc.), ionic liquids, and mixed solvents thereof.

  The content of the solvent used in the coating layer of the silver salt emulsion of the present embodiment is in the range of 30 to 90% by mass with respect to the total mass of the silver salt and binder contained in the silver salt emulsion layer, and 50 It is preferable to be in the range of ˜80 mass%.

<Other additives>
There are no particular restrictions on the various additives used in the present embodiment, and known ones can be preferably used.

[Other layer structure]
A protective layer (not shown) may be provided on the silver salt emulsion coating layer. In the present embodiment, the “protective layer” means a layer made of a binder such as gelatin or a high molecular polymer, and is formed on a silver salt emulsion layer having photosensitivity in order to exhibit an effect of preventing scratches and improving mechanical properties. It is formed. The thickness is preferably 0.5 μm or less. The coating method and forming method of the protective layer are not particularly limited, and a known coating method and forming method can be appropriately selected. Also, for example, an undercoat layer can be provided below the silver salt emulsion coating layer.

  Next, each process of the manufacturing method of the electrically conductive sheet 10 of this invention is demonstrated.

[exposure]
The present embodiment includes a case where the pattern of the first conductive portion 12A in FIG. 2a and the pattern of the second conductive portion 12B in FIG. 2b are applied by a printing method. A pattern of the second conductive portion 12B is formed by exposure and development. That is, pattern exposure is performed on a photosensitive material having a silver salt-containing layer provided on the first transparent substrate 11A and the second transparent substrate 11B or a photosensitive material coated with a photopolymer for photolithography. The pattern exposure can be performed by an exposure method through a mask of a pattern as shown in FIGS. 6a and 6b provided with 2a, 2b or an electrode connection portion, or by a method by scanning exposure. The exposure can be performed using electromagnetic waves. Examples of the electromagnetic wave include light such as visible light and ultraviolet light, and radiation such as X-rays. Further, a light source having a wavelength distribution may be used for exposure, and a light source having a specific wavelength may be used.

[Development processing]
In this embodiment, after the emulsion layer is exposed, further development processing is performed. The development processing can be performed by a normal development processing technique used for silver salt photographic film, photographic paper, printing plate-making film, photomask emulsion mask, and the like. The developer is not particularly limited, but PQ developer, MQ developer, MAA developer and the like can also be used, and commercially available products include, for example, CN-16, CR-56, CP45X, FD prescribed by Fuji Film -3, Papitol, a developer such as C-41, E-6, RA-4, D-19, D-72, etc. formulated by KODAK, or a developer included in the kit can be used. A lith developer can also be used.

  The development processing in the present invention can include a fixing processing performed for the purpose of removing and stabilizing the silver salt in the unexposed portion. For the fixing process in the present invention, a fixing process technique used for silver salt photographic film, photographic paper, film for printing plate making, emulsion mask for photomask, and the like can be used.

  The fixing temperature in the fixing step is preferably about 20 ° C. to about 50 ° C., more preferably 25 to 45 ° C. The fixing time is preferably 5 seconds to 1 minute, more preferably 7 seconds to 50 seconds. The replenishing amount of the fixing solution is preferably 600 ml / m 2 or less, more preferably 500 ml / m 2 or less, and particularly preferably 300 ml / m 2 or less with respect to the processing amount of the photosensitive material.

  The light-sensitive material that has been subjected to development and fixing processing is preferably subjected to water washing treatment or stabilization treatment. In the water washing treatment or stabilization treatment, the washing water amount is usually 20 liters or less per 1 m 2 of the light-sensitive material, and can be replenished in 3 liters or less (including 0, ie, rinsing with water).

  The mass of the metallic silver contained in the exposed portion after the development treatment is preferably a content of 50% by mass or more, and 80% by mass or more with respect to the mass of silver contained in the exposed portion before exposure. More preferably. If the mass of silver contained in the exposed portion is 50% by mass or more based on the mass of silver contained in the exposed portion before exposure, it is preferable because high conductivity can be obtained.

  The gradation after the development processing in the present embodiment is not particularly limited, but is preferably more than 4.0. When the gradation after the development processing exceeds 4.0, the conductivity of the conductive metal portion can be increased while keeping the light transmissive property of the light transmissive portion high. Examples of means for setting the gradation to 4.0 or higher include the aforementioned doping of rhodium ions and iridium ions.

  Although the conductive sheet is obtained through the above steps, the surface resistance of the obtained conductive sheet is 0.1 to 100 ohm / sq. (□) is preferable, and 1 to 10 ohm / sq. It is more preferable that it is in the range of (□). Further, the conductive sheet after the development treatment may be further subjected to a calendar treatment, and can be adjusted to a desired surface resistance by the calendar treatment.

[Physical development and plating]
In the present embodiment, for the purpose of improving the conductivity of the metallic silver portion formed by the exposure and development processing, physical development and / or plating treatment for supporting the conductive metal particles on the metallic silver portion is performed. May be. In the present invention, the conductive metal particles may be supported on the metallic silver portion by only one of physical development and plating treatment, or the conductive metal particles are supported on the metallic silver portion by combining physical development and plating treatment. May be. In addition, the thing which performed the physical development and / or the plating process to the metal silver part is called "conductive metal part".

  “Physical development” in the present embodiment means that metal particles such as silver ions are reduced by a reducing agent on metal or metal compound nuclei to deposit metal particles. This physical phenomenon is used for instant B & W film, instant slide film, printing plate manufacturing, and the like, and the technology can be used in the present invention. The physical development may be performed simultaneously with the development processing after exposure or separately after the development processing.

  In the present embodiment, the plating treatment can use electroless plating (chemical reduction plating or displacement plating), electrolytic plating, or both electroless plating and electrolytic plating. For the electroless plating in the present embodiment, a known electroless plating technique can be used, for example, an electroless plating technique used in a printed wiring board or the like can be used. Plating is preferred.

[Oxidation treatment]
In the present embodiment, it is preferable to subject the metallic silver portion after the development treatment and the conductive metal portion formed by physical development and / or plating treatment to oxidation treatment. By performing the oxidation treatment, for example, when a metal is slightly deposited on the light transmissive portion, the metal can be removed and the light transmissive portion can be made almost 100% transparent.

[Conductive metal part]
The line width of the conductive metal portion (also referred to as a conducting wire) of the present embodiment is preferably 0.1 μm or more and 25 μm or less, more preferably 1 μm or more and 20 μm or less, still more preferably 1 μm or more and 15 μm or less, most preferably 1 μm or more, 10 μm or less. When the line width is less than the above lower limit value, the conductivity becomes insufficient, so that when used for a touch panel, the detection sensitivity becomes insufficient. On the other hand, when the above upper limit is exceeded, moire caused by the conductive metal portion becomes noticeable, or visibility is deteriorated when used for a touch panel. In addition, by being in the said range, the moire of an electroconductive metal part is improved and visibility becomes especially good.
The line spacing (here the pitch between the fine line patterns in FIGS. 2a and 2b) is as described above. The conductive metal portion may have a portion whose line width is wider than 200 μm for the purpose of ground connection or the like.
In the first aspect of the present invention, the capacitance sensing unit has a shape without an opening (also referred to as a solid), and in the second aspect of the present invention, the capacitance sensing unit has a nested shape in which large and small similar shapes are formed. In the present invention, it has a mesh shape. The nest and the mesh have an opening in its outer shape. In the case of having an opening, the line width of the conductive portion may be the same as the line width of the conducting wire, or can be adjusted within a range that does not interfere with capacitance sensing.

  The conductive metal portion in the present embodiment has an aperture ratio (transmittance) of preferably 85% or more, more preferably 90% or more, and 95% or more from the viewpoint of visible light transmittance. Is most preferred. The aperture ratio is the ratio of the entire translucent portion excluding the conductive portion. For example, the aperture ratio of a square lattice having a line width of 15 μm and a pitch of 300 μm is 90%.

[Light transmissive part]
The “light transmissive part” in the present embodiment means a part (also expressed as an opening part) having translucency other than the conductive metal part in the conductive sheet of the present invention. The transmittance in the light transmissive portion is 90% or more, preferably 95% or more, and the transmittance indicated by the minimum value of the transmittance in the wavelength region of 380 to 780 nm excluding the contribution of light absorption and reflection of the transparent substrate. Preferably it is 97% or more, still more preferably 98% or more, and most preferably 99% or more.

  Regarding the exposure method, a method through a glass mask or a pattern exposure method by laser drawing is preferable.

[Conductive sheet 10 (10A, 10B) of the present invention]
The thickness of the transparent substrate 11 (11A, 11B) in the conductive sheet 10 (10A, 10B) according to the present embodiment 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.

The thickness of the portion (the developed metallic silver portion, also referred to as the conductive metal portion) constituting the fine wire portion and the sensing portion which are conductive wires provided on the transparent substrate 11 (11A, 11B) is the transparent substrate 11 ( 11A, 11B) can be appropriately determined according to the coating thickness of the silver salt-containing layer coating applied. The thickness of the metallic silver part can be selected from 0.01 μm to 0.2 mm, preferably 30 μm or less, more preferably 20 μm or less, and still more preferably 0.01 to 9 μm. And most preferably 0.05 to 5 μm.
The metallic silver part may be a single layer or a multilayer structure of two or more layers. When the metallic silver part has a pattern and has a multilayer structure of two or more layers, different color sensitivities can be imparted so as to be sensitive to different wavelengths. Thereby, when the exposure wavelength is changed and exposed, a different pattern can be formed in each layer. This will be specifically described with reference to FIG. When the photosensitive material is used, for example, if the silver salt-containing paint layer of 12A is green-sensitive, it can be a layer that is sensitive to green light but not red light, and the silver salt-containing paint layer of 12B is red. When photosensitive, it can be a layer that is sensitive to red light but not green light. When this principle is used, when the pattern exposure of FIG. 2a is performed with green light, the pattern exposure of FIG. 2b is performed with red light, and then development processing is performed, the conductive pattern of the perspective view of FIG. 2c is obtained. Can be obtained.

  As the thickness of the conductive metal part, the thinner the display panel, the wider the viewing angle of the display panel, and the thinner the display is required for improving the visibility. From such a viewpoint, it is desirable that the thickness of the layer made of the conductive metal carried on the conductive portion is thinner than the above, and the following range can be set by using the silver salt-containing layer. Is possible. It is preferably less than 9 μm, more preferably from 0.1 μm to less than 5 μm, and even more preferably from 0.1 μm to less than 3 μm.

  In the present embodiment, the thickness of the layer made of conductive metal particles is formed by controlling the coating thickness of the silver salt-containing layer described above to form a metallic silver portion having a desired thickness, and further by physical development and / or plating treatment. Therefore, even the conductive sheet 10 having a thickness of less than 5 μm, preferably less than 3 μm can be easily formed.

  In the method for manufacturing the conductive sheet 10 according to the present embodiment, it is not always necessary to perform a process such as plating. This is because in the method for manufacturing the conductive sheet 10 according to the present embodiment, a desired surface resistance can be obtained by adjusting the coating silver amount of the silver salt emulsion layer and the silver / binder volume ratio. In addition, you may perform a calendar process etc. as needed.

(Hardening after development)
It is preferable to perform a film hardening process by immersing the film in a hardener after the silver salt emulsion layer is developed. Examples of the hardener include dialdehydes such as glutaraldehyde, adipaldehyde, 2,3-dihydroxy-1,4-dioxane, and those described in JP-A-2-141279 such as boric acid. .

  In addition, this invention can be used in combination with the technique of the publication gazette and international publication pamphlet which are described in following Table 1 and Table 2. FIG. Notations such as “JP,” “Gazette” and “No. Pamphlet” are omitted.

  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.

(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 are added to the silver bromide grains. And Ir 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. Using this coating solution, it was applied onto the first transparent substrate 11A and the second transparent substrate 11B (here, both polyethylene terephthalate (PET)) so that the silver coating amount was 10 g / m ² . Layers for forming the conductive portions 12A and 12B were provided. At this time, the volume ratio of Ag / gelatin was 2/1.

  At the time of the above application, the PET film drawn out from the roll having a width of 30 cm is applied to the central part of the PET film with a coating width of 25 cm and a length of 20 m, and both ends are cut off by 3 cm so as to leave the central part of the application, and rolled. Silver halide photosensitive material (photosensitive material for forming the conductive sheets 10A and 10B in FIG. 1b. Since it has not been exposed and developed, it is not a conductive sheet. 10b). A conductive pattern is formed on the photosensitive material by applying a conductive pattern by the method described below.

(exposure)
At the time of pattern exposure, a second conductive sheet is used by using a photomask having the pattern of FIG. 6a (capacitance sensing unit is omitted) showing the conductive pattern of the first aspect of the present invention to form the first conductive sheet 10A. In order to make 10B, a photomask having a pattern shown in FIG. 6B was used. The size of the photomask is A4 size (210 mm × 297 mm, 297 mm × 210 mm). The photomask is brought into close contact with each of the photosensitive materials prepared above, and surface exposure is performed using parallel light using a high-pressure mercury lamp as a light source. . The details of the photomask pattern used will be described in detail in the following examples.

(Development processing)
The photosensitive materials 10a and 10b on which the latent images were formed in the patterns of FIGS. 6a and 6b obtained above were subjected to the following development processing to produce conductive sheets 10A and 10B on which conductive patterns were formed.
・ Developer 1L formulation 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
Adjusted to pH 10.3 and formulated 1L fixer 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

The exposed photosensitive materials 10a and 10b were developed under the following processing conditions using an automatic developing machine (FG-710PTS) manufactured by FUJIFILM Corporation using the processing agent. The processing conditions were development at 35 ° C. for 30 seconds, fixing at 34 ° C. for 23 seconds, and washing with running water (5 L / min) for 20 seconds.
After the above treatment, the conductive sheets 10A and 10B on which the conductive pattern is formed are dried, and then overlapped so that the PET surface 11A of the conductive sheet 10A and the conductive layer 12B of the conductive sheet 10B are in contact with each other as shown in FIG. It was. The overlapping was set so that the conductive pattern of the conductive sheet 10A and the conductive pattern of the conductive sheet 10B were orthogonal when seen through from above. The peripheral portion of the laminated conductive sheet where the virtual lattice is not formed is covered with a material that does not transmit light so that it can be overlaid with the image display device. It should be noted that the lead wire can be drawn out from the end of the electrode so that it can be driven as a touch panel.

Example 1
In the first embodiment, a case will be described in which the capacitance sensing unit which is the conductive pattern of the first aspect of the present invention has no opening (also referred to as a solid).
(Conductive sheet 1-1)
The photomask used to create the conductive sheet 10 laminated with the conductive sheet 1-1 is a square lattice having a virtual lattice shape of 300 μm × 300 μm when the conductive sheet 10 is seen through from above. A capacitance sensing unit having a square area of 2025 μm ² (45 μm × 45 μm) is installed at the center of each side of the square lattice, and the line width of the thin line part (also referred to as a conducting wire part) excluding the capacitance sensing part Is 10 μm, and the electrode pitch is designed to be 6 mm.

(Conductive sheet 1-2 to 1-27)
In contrast to the conductive sheet 1-1, the conductive sheets 1-2 to 1-7 have the thin wire portions (also referred to as conducting wire portions) changed in line width as shown in Table 3, and the conductive sheets 1-8 to 1-13 are static. The capacitance sensing area is changed as shown in Table 3, the conductive sheets 1-14 to 1-17 are changed in side length of the virtual lattice as shown in Table 3, and the conductive sheets 1-18 and 19 are changed to the conductive sheet 1. The capacitance sensing area for -5 and 6 is changed as shown in Table 3, and the capacitance sensing area for the conductive sheets 1-20 to 1-23 is as shown in Table 3 for the conductive sheet 1-17. The conductive sheets 1-24 and 25 are changed in the pitch of the electrodes with respect to the conductive sheet 1-1 as shown in Table 3, and the conductive sheets 1-26 and 27 are formed in a circular shape and a diamond shape in the capacitance sensing unit. It has been changed.

  The following items were evaluated for the conductive sheets 1-1 to 1-27, and the results are shown in Table 3. For touch detection evaluation, a commercially available touch panel sensor IC having a panel size of 8 to 10 type and having 20 or more X electrodes and Y electrodes (Synaptics electrode line number 26 × 22) is used. Then, a simple experimental device was created by connecting the conductive sheets and evaluated.

(Reproducibility of touch detection)
Touching the same position of the conductive sheet 50 times continuously, whether or not touch detection was detected with good reproducibility was evaluated. This evaluation was carried out at 10 locations by changing the location. × Evaluation Sometimes it is not detected more than once at multiple locations.
△ Evaluation May not be detected when the measurement is over 10 places.
○ Evaluation Stable detection.
◎ Stable even if the number of evaluations is 100 times or more

(Touch detection position detection accuracy)
Evaluation was made based on whether or not the displayed positions varied during the continuous touch.
X Evaluation Variation is recognized.
○ Evaluation Stablely detected.

(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 The transmittance is 94% or more and it is bright enough.

(Visibility)
Evaluated by the ease of viewing the screen. 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 roughness or line thickness on the screen.
ΔEvaluation You may feel rough or thick lines depending on the viewing direction.
○ Evaluation The screen looks uniform.

From the results in Table 3, the following points were found in the first invention of the present case.
When the line width of the thin wire | line part (conductive wire) of the thin wire conductive pattern of the conductive sheets 1-5 and 6 exceeds 20 micrometers, it turned out that a screen is a problem. Furthermore, it has been found that there is a possibility that a problem may occur in the reproducibility of touch sensing in the conductive sheet 1-7 in which the line width of the thin wire portion (conductive wire) is less than 1 μm.
From the results of the conductive sheets 1-8 to 13, it has been found that when the area of the capacitance sensing portion is less than 625 μm ² , the touch sensing accuracy is poor, and when it exceeds 3600 μm ² , the screen is dark.
Furthermore, from the results of the conductive sheets 1-9 to 12, 22, and 23, when the side length of the square capacitance sensing unit exceeds 70 μm, the screen may feel rough, and when it exceeds 100 μm, the roughness is surely felt. I understood it.
In addition, it was also found that in the conductive sheet 1-25 in which the electrode pitch is 12 mm, the specification of the touch position becomes unstable.
The conductive sheet 1-22 has a feeling of roughness on the screen, and the conductive sheets 1-14, 18 and 19 may not detect touch. In the conductive sheet 1-25, when touching at the same position is repeated, two or more positions are detected. It was sometimes seen to detect.
From the comparison of the results of the conductive sheets 1-1, 26, and 27, it was also found that if the area of the capacitance sensing unit is the same area, there is no significant difference in performance even if the shape is square, circular or rhombus.
Furthermore, in the first invention in which the capacitance sensing unit is a solid conductive unit without an opening, the side length of the capacitance sensing unit is limited as described above based on the results of the conductive sheets 1-17 to 23. Therefore, it was found that the touch detection accuracy is inferior when the side length of the virtual lattice is increased.

(Example 2)
In the second embodiment, a case where the electrostatic capacitance sensing unit, which is the conductive pattern of the second aspect of the present invention, has an opening and is nested and a case where it is a mesh will be described.
(Conductive sheet 2-1)
The photomask used to create the conductive sheet 10 in which the conductive sheets 2-1 are laminated is a square lattice having a virtual lattice shape of 1000 μm × 1000 μm when the conductive sheet 10 is seen through from above. Four squares are nested in the center of each side of the square lattice (outside is 40 μm × 40 μm in outer shape, 100 μm × 100 μm in outer shape, 160 μm × 160 μm outside, 220 μm × 220 μm outside) In this case, a capacitance sensing unit having a side width of 10 μm is installed, and the line width of the thin line portion (also referred to as a conductor portion) excluding the capacitance sensing unit is 10 μm, and the pitch of the electrodes Is designed to be 6 mm.

(Conductive sheets 2-2 to 2-13)
For the conductive sheet 2-1, when the conductive sheet 2-2 is changed to five nestings, the conductive sheets 2-3 and 2-4 are when the size of the nesting is changed to 2-2, In the conductive sheet 2-5, the innermost nesting of 2-3 is solid, and the width of each nesting is narrowed toward the outside.
The conductive sheets 2-6 to 2-8 are cases where the square nesting of the conductive sheets 2-3 to 2-5 is rotated 45 degrees to form a rhombus.
The conductive sheets 2-9 to 2-11 are cases where the square nesting of the conductive sheets 2-3 to 2-5 is changed to a circular nesting.
The conductive sheet 2-12 is a mesh-shaped case in which the capacitance sensing part has an outer shape of 410 μm × 410 μm and is divided into 16 mm with a line width of 10 μm.
The conductive sheet 2-13 is a case where the mesh-shaped capacitance sensing unit of the conductive sheet 2-12 is rotated by 45 ° to form a rhomboid capacitance sensing unit.

In Table 4, the conductive sheet 1-1 of the first aspect of the present invention is described. However, in the aspect of the second aspect of the present invention, the electrostatic capacity sensing unit has an opening, so that the brightness of the sheet and the accuracy of touch sensing are improved. be able to. However, regarding the size of the capacitance sensing unit, when the virtual lattice is a square lattice of 1000 μm × 1000 μm, when compared with the conductive sheets 2-4, 2-7, 2-10, the square of 2-4 Since nesting in the XY axis causes an overlap in the XY axes, it is not preferable, and a diamond or circular nesting is preferable.
In addition, it was confirmed that the capacitance sensing unit with the nested structure has an advantage that the brightness of the screen can be ensured by making the line width wider and thinner on the inner side.
In addition, it is known to improve the accuracy of touch sensing by providing a mesh-shaped capacitance sensing unit, but structurally, the same sensing accuracy and brightness are achieved by a simple diamond-shaped nesting. I also found that I can do it.

(Example 3)
As a performance required for a touch panel used for an image display device such as a liquid crystal display device, the transmittance of the touch panel is required to be 85% or more in order to maintain the brightness of the screen. Further, the resistance value of the electrode greatly depends on the size of the screen because the driving load for detecting the touch position increases as the screen becomes larger. That is, when used for a panel of 8 inches or less, there is no problem with a sheet resistance value of about 100 Ω / □ such as an ITO film that is commonly used at present, but for the 32 inch type, about 10 Ω / □ is necessary. For the inch type, 5Ω / □ or less is required.
In Example 3, the suitability when the screen was enlarged using the material and ITO used in this case was examined.
Since the sheet resistance value (surface resistance) of the conductive sheet using the silver halide photosensitive material of the present invention can be variously changed, a mesh-shaped conductive sheet with a uniform conductive material is created as a model, and the sheet The resistance value (surface resistance) was measured.
The photomask used for pattern formation in Example 3 has a mesh pitch of 300 μm and a line width of 10 μm.
The sheet resistance value (surface resistance) was measured at an arbitrary 10 points with a Lorester GP (model number MCP-T610) series 4-probe probe (ASP) manufactured by Dia Instruments, and the average value was obtained.
In order to confirm the transparency of the model conductive sheet, the transmittance (wavelength 550 nm) was measured using a spectrophotometer.

(Example 3-1)
A sample was cut into 10 cm × 10 cm from the roll-shaped silver halide photosensitive materials 10a and 10b of Example 1, and exposed through the photomask for creating the model conductive sheet. The exposed sample was developed in the same manner as in Example 1 to prepare samples of Examples 3-1a and b. The sheet resistance value of this sample was 15Ω / □ for both samples, and the transmittance was 93%.
(Example 3-2)
A sample was prepared in the same manner as in Example 3-1, except that the silver coating amount of the light-sensitive material of Example 3-1 was increased and the additive was adjusted so as to improve the dissolution physical developability of the developer. . Further, this sample was calendered and dipped in a borohydrate (NaBH ₄ ) solution to obtain a sample of Example 3-2 having a sheet resistance of 1.2Ω / □ and a transmittance of 93%.
(Example 3-3)
A sample of Example 3-3 was prepared by performing the same process as in Example 3-2 except that the line width of the photomask used for pattern formation in Example 3-2 was changed to 20 μm. The sheet resistance value of this sample was 0.7Ω / □, and the transmittance was 88%.

(Comparative Examples 3-1 and 2)
An ITO film was formed on the PET film used in Example 1 by sputtering. The thickness of the ITO film was adjusted so that the sheet resistance was 100 Ω / □ in Comparative Example 3-1, and the sheet resistance was adjusted to 20 Ω / □ in Comparative Example 3-2. The transmittance of Comparative Example 3-1 of the ITO sample prepared in this manner was 88% and almost colorless, and the transmittance of Comparative Example 3-2 was 78% and was slightly yellowish.
From the above, Examples 3-2 and 3-3 can be applied to 32-inch type and 42-inch type, but Comparative Example 3-2 has insufficient sheet resistance value, insufficient transmittance, and coloring. I found that there were problems such as anxiety.

Example 4
The roll-shaped silver halide photosensitive material used in Example 1 was subjected to pattern exposure using a photomask having the pattern of FIGS. 14a and 14b, and subjected to development processing similar to Example 1, and conductive sheets a and b were formed. Created. The pattern is exposed using a photomask having the pattern shown in FIGS. 6A and 6B, and compared with the conductive sheets a ′ and b ′ prepared by performing the same development process as in Example 1, the electrodes connected to the signal processing unit. The difference is that a dummy electrode that is not coupled to the electrode is formed therebetween. By grounding the dummy electrodes of the conductive sheets a and b, it is possible to reduce the stray capacitance (parasitic capacitance) generated in the electrodes connected to each signal processing unit, thereby reducing the RC time constant when the panel is used. A touch panel with a screen can be formed.

DESCRIPTION OF SYMBOLS 10 Conductive sheet 11 Transparent base | substrate 12A 1st electroconductive part 12B 2nd electroconductive part 13A 1st fine wire pattern 13B 2nd fine wire pattern 14A The fine wire part 14B of the 1st fine wire pattern Fine wire part 15A of the 1st fine wire pattern Capacitance sensing unit 15B Second capacitance sensing unit of second fine line pattern a Width of first fine line pattern and thin line of second fine line pattern b Width of capacitance sensing unit of first fine line pattern and second fine line pattern D Virtual unit cell (Fig. 2c)
Xi, Yj DX, DY dummy electrode La, Lb representing XY electrodes Electrode lead line connection part

Claims (20)

A conductive sheet having a transparent substrate, a first conductive portion formed on one main surface of the transparent substrate, and a second conductive portion in contact with the other main surface of the transparent substrate;
Each of the first conductive portions has two or more first fine wire conductive patterns extending in a first direction and arranged in a second direction orthogonal to the first direction,
Each of the second conductive portions has two or more second fine wire conductive patterns extending in a third direction and arranged in a fourth direction orthogonal to the third direction,
The first fine wire conductive pattern has a conductive fine wire portion and a first capacitance sensing portion formed at a predetermined interval on the thin wire,
The second thin wire conductive pattern has a conductive thin wire portion and a second capacitance sensing portion formed at a predetermined interval on the thin wire,
The first fine wire conductive pattern and the second fine wire conductive pattern are disposed so as to intersect when the conductive sheet is seen through, and the first and second fine wire conductive patterns are substantially linear. And the line width a of the thin line portion is 0.1 to 25 μm, and the first and second capacitance sensing portions are not open.   The conductive sheet according to claim 1, wherein the first and second fine wire conductive patterns have a thickness of 1 to 10 μm. The first and second capacitance sensing units of the first and second thin wire conductive patterns contain 80% by mass or more of silver as a constituent component and have an area of 400 to 6400 μm ^2. The conductive sheet according to claim 1 or 2. The first and second capacitance sensing units of the first and second thin wire conductive patterns contain ITO or conductive fiber as a constituent component and have an area of 400 to 18000 μm ^2. The conductive sheet according to claim 1 or 2.   The shape of the first and second capacitance sensing parts of the first and second thin wire conductive patterns is any one of a square, a rectangle, a diamond, a polygon, a circle, and an ellipse. The conductive sheet according to any one of claims 1 to 4. Each of the first conductive portions includes two or more first fine wire conductive patterns extending in a first direction and arranged in a second direction orthogonal to the first direction, One thin wire conductive pattern is disposed at a distance of 200-1500 μm,
Each of the second conductive portions has two or more second thin wire conductive patterns extending in a third direction and arranged in a fourth direction orthogonal to the third direction. The conductive sheet according to any one of claims 1 to 5, wherein the two fine wire conductive patterns are disposed at a distance of 200 to 1500 µm.   The first conductive part has a plurality of X electrodes arranged at intervals of 4 to 9 mm, the X electrode is formed by combining a plurality of first fine wire conductive patterns, and the second conductive part is 4 to 4 mm. The conductive sheet according to claim 6, comprising a plurality of Y electrodes arranged at intervals of 9 mm, wherein the Y electrodes are formed by combining a plurality of second thin wire conductive patterns. A conductive sheet having a transparent substrate, a first conductive portion formed on one main surface of the transparent substrate, and a second conductive portion in contact with the other main surface of the transparent substrate;
Each of the first conductive portions has two or more first fine wire conductive patterns extending in a first direction and arranged in a second direction orthogonal to the first direction,
Each of the second conductive portions has two or more second fine wire conductive patterns extending in a third direction and arranged in a fourth direction orthogonal to the third direction,
The first fine wire conductive pattern has a conductive fine wire portion and a first capacitance sensing portion formed at a predetermined interval on the thin wire,
The second thin wire conductive pattern has a conductive thin wire portion and a second capacitance sensing portion formed at a predetermined interval on the thin wire,
The first fine wire conductive pattern and the second fine wire conductive pattern are disposed so as to intersect when the conductive sheet is seen through, and the first and second fine wire conductive patterns are substantially linear. And the line width a of the thin line portion is 0.1 to 25 μm, and the first and second capacitance sensing portions have openings.   The conductive sheet according to claim 8, wherein the first and second fine wire conductive patterns have a thickness of 1 to 10 μm. The first and second capacitance sensing units of the first and second thin wire conductive patterns contain 80% by mass or more of silver as a constituent component, and have an outer area of 10,000 to 500,000 μm ^2. The conductive sheet according to claim 8 or 9.   The first and second capacitance sensing portions of the first and second fine wire conductive patterns are disposed at 200 to 1500 μm in the thin wire portions of the first and second fine wire conductive patterns. The conductive sheet according to any one of claims 8 to 10.   The first and second capacitance sensing units are formed by nesting a plurality of similar shapes having different sizes in the thin line portions of the first and second thin line patterns. The conductive sheet according to claim 11.   The conductive sheet according to claim 12, wherein a plurality of similar nesting shapes having different sizes are any one of a circle, a square, a diamond, an ellipse, a rectangle, and a polygon. Each of the first conductive portions includes two or more first fine wire conductive patterns extending in a first direction and arranged in a second direction orthogonal to the first direction, One thin wire conductive pattern is disposed at a distance of 200-1500 μm,
Each of the second conductive portions has two or more second thin wire conductive patterns extending in a third direction and arranged in a fourth direction orthogonal to the third direction. The conductive sheet according to any one of claims 8 to 13, wherein the two fine wire conductive patterns are arranged at a distance of 200 to 1500 µm.   The first conductive part has a plurality of X electrodes arranged at intervals of 4 to 9 mm, the X electrode is formed by combining a plurality of first fine wire conductive patterns, and the second conductive part is 4 to 4 mm. The conductive sheet according to claim 14, comprising a plurality of Y electrodes arranged at an interval of 9 mm, wherein the Y electrodes are formed by combining a plurality of second thin wire conductive patterns. A conductive sheet having a transparent substrate, a first conductive portion formed on one main surface of the transparent substrate, and a second conductive portion in contact with the other main surface of the transparent substrate;
Each of the first conductive portions has two or more first fine wire conductive patterns extending in a first direction and arranged in a second direction orthogonal to the first direction,
Each of the second conductive portions has two or more second fine wire conductive patterns extending in a third direction and arranged in a fourth direction orthogonal to the third direction,
The first fine wire conductive pattern has a conductive fine wire portion and a first capacitance sensing portion formed at a predetermined interval on the thin wire,
The second thin wire conductive pattern has a conductive thin wire portion and a second capacitance sensing portion formed at a predetermined interval on the thin wire,
The first fine wire conductive pattern and the second fine wire conductive pattern are disposed so as to intersect when the conductive sheet is seen through, and the first and second fine wire conductive patterns are substantially linear. And the line width a of the thin line portion is 0.1 to 25 μm, and the first and second capacitance sensing portions have a fine mesh structure.   The conductive sheet is a surface on which the first conductive portion of the first transparent substrate is not formed after the first conductive portion is formed on the first transparent substrate and the second conductive portion is formed on the second transparent substrate. The conductive sheet according to any one of claims 1 to 16, wherein the conductive sheet is formed by bonding the first conductive portion and the second conductive portion.   The said conductive sheet formed the 2nd conductive part in the surface in which the conductive part of the 1st transparent substrate is not formed, after forming the 1st conductive part on the 1st transparent substrate. The conductive sheet according to any one of 1 to 16.   The conductive sheet according to claim 17 or 18, wherein a protective layer is provided on at least one of the surfaces of the conductive sheet that are not in contact with the transparent substrate of the first and second conductive portions.   A capacitive touch panel comprising the conductive sheet according to claim 1.

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