JP2012221891A - Transparent conductive sheet, sensitive material for production of transparent conductive sheet, production method of transparent conductive sheet, and capacity type touch panel using these transparent conductive sheets - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the visibility of a touch panel by reducing the difference of hue of the conductive pattern (electrode) of a transparent conductive sheet (electrode sheet).SOLUTION: A transparent conductive sheet (electrode sheet) consisting of conductive thin lines of developed silver is produced by performing pattern exposure and development of a sensitive material where a photosensitive layer containing a silver halide emulsion is formed on a transparent support. The photosensitive layer consists of at least any one of a plurality of photosensitive layers containing an emulsion of different halogen composition, a plurality of photosensitive layers containing a silver halide emulsion of different silver density, and a plurality of photosensitive layers having different additive amount of development inhibitor.

Description

  The present invention relates to a transparent conductive sheet having a high-definition pattern of conductive fine lines formed on a transparent support, a photosensitive material for producing a transparent conductive sheet having a high-definition pattern of conductive thin lines, and a transparent conductive sheet. The present invention relates to a manufacturing method and a capacitive touch panel using these transparent conductive sheets.

In recent years, in the field of touch panels, projection capacitive touch panels have been widely used for PDAs, mobile phones, and the like, and attempts to increase the size of touch panels of this type have begun. When increasing the size of the panel, it is essential to reduce the resistance of the transparent electrode. As a technique for reducing the resistance, a method of forming a capacitance sensing portion with a mesh-like conductive thin wire is disclosed in, for example, Patent Literature 1 and 2. The method for forming a mesh-like conductive fine wire described in these documents is a conductive ink printing method or thinning by photolithography of ITO or a metal thin film. In the former printing method, the method is 20 μm or less. There is a problem that it is difficult to stably form a thin line having a line width, and in the latter case, a high cost is required because the photolithography process includes a plurality of processes.
On the other hand, a method of forming a low-resistance conductive fine wire from a silver image obtained by developing a silver halide photographic light-sensitive material has been studied in the field of electromagnetic shielding films and printed wiring. In this development method, various patterns can be formed by exposure through a mask and subsequent development processing, so that the manufacturing process is stable. As a developing system, for example, Patent Document 3 can be cited, and an example of a surface resistance of 50 to 100Ω / □ with a mesh pattern having a fine line width of 20 μm and a lattice spacing of 250 μm is described.

JP 2010-039537 A International Publication No. 2010/014683 JP 2007-188655 A

  In recent years, attempts have been made to apply the above development method to the formation of electrodes for capacitive touch panels, but the color of the conductive thin wires formed from the developed silver varies slightly depending on various conditions. It has been found that there is a problem that the visibility of the touch panel is not good. In addition, the phenomenon that the color of the manufactured conductive thin wire varies depending on the manufacturing conditions is such that a thick electrode is formed even in a method of printing a conductive ink such as silver paste or a method using vapor deposition or sputtering. It was also found that it may be observed.

The present invention has been made in consideration of such problems, and an object thereof is to provide a transparent conductive sheet in which the color tone of the surface of a conductive pattern (which can be read as an electrode depending on the field of use) is controlled. To do. Another object of the present invention is to provide a transparent conductive sheet in which the color tone of an electrode made of developed silver is controlled. Moreover, this invention aims at provision of the manufacturing method of the transparent conductive sheet which controlled the color tone of these electrodes.
Furthermore, an object of the present invention is to provide a transparent electrode that can be used for a touch panel having a touch surface with little color unevenness by controlling the color tone of the electrode. Furthermore, an object of the present invention is to provide a transparent conductive pattern that can be used for a touch panel having an achromatic touch surface by controlling the color tone of an electrode.
In particular, an object of the present invention is to provide a transparent conductive pattern that has no color unevenness, is easily visible with an achromatic color, has low resistance, and can be used for a large-screen touch panel.
Furthermore, another object of the present invention is to provide a conductive sheet that can be used for an electromagnetic wave shield whose color tone is controlled.
In the conductive sheet of the present invention, a “conductive pattern made of conductive thin wires” is used for various purposes, so it is simplified and referred to as a “conductive pattern”. However, when used for electrode applications such as a touch panel, it is easy to understand. Prioritize the use of “conductive pattern” and “electrode”.

  The present inventors have found that the phenomenon in which the above-mentioned color tone varies depending on the conditions for producing a conductive pattern (also referred to as color unevenness or color unevenness) is more likely to be observed as the thickness of the conductive pattern film increases, and the conductive sheet 2 When using a sheet and the observer sees only the same side surface of the two conductive patterns, it is difficult to observe color unevenness, the conductive pattern surface far from the support and the conductive pattern close to the support When observed alternately with the surface, it is particularly easy to observe, and not only when the conductive pattern is formed as a fine pattern, but also with the color observed through the support in the sample in which a uniform conductive film is formed on the support. The inventors have found that the color observed from the surface of the conductive film is different. From these facts, the surface of the thin film at the initial stage of the conductive pattern formation process and the support-side surface of the conductive pattern that has become a thick film as the process proceeds are due to the difference in the microstructure of the metal that is the conductive material. The color of the reflected light is estimated to be different, leading to the invention of the following aspect.

1) A photosensitive material for producing a transparent conductive sheet for producing a transparent conductive sheet composed of conductive thin wires by subjecting a photosensitive material having a photosensitive layer containing a silver halide emulsion to a transparent support to pattern exposure and development. The photosensitive layer is composed of at least one of a plurality of photosensitive layers containing emulsions having different halogen compositions, a plurality of photosensitive layers having different silver densities, and a plurality of photosensitive layers having different addition amounts of development inhibitors. A photosensitive material for producing a transparent conductive sheet.
2) The photosensitive material is a photosensitive material for producing a conductive sheet in which a photosensitive layer containing a silver halide emulsion is formed on both sides of a transparent support, and the photosensitive layer on at least one side of the photosensitive layer is Item 1 is characterized in that it comprises at least one of a plurality of photosensitive layers containing emulsions having different halogen compositions, a plurality of photosensitive layers having different silver densities, and a plurality of photosensitive layers having different addition amounts of development inhibitors. The photosensitive material for transparent conductive sheet manufacture of description.
3) The silver halide emulsion of the photosensitive layer is a silver chlorobromide emulsion, and the silver bromide content is closer to the transparent support surface than the central portion of the photosensitive layer, or the support. Item 3. The photosensitive material for producing a transparent conductive sheet according to Item 1 or 2, wherein the silver bromide content of the photosensitive layer farthest from the substrate is 5 mol% or more.
4) The silver bromide content of the silver chlorobromide emulsion at the center of the photosensitive layer is less than 40 mol%, and the salt of the photosensitive layer at the portion closest to the transparent support surface or the portion of the photosensitive layer furthest from the support. Item 4. The photosensitive material for producing a transparent conductive sheet according to Item 3, wherein the silver bromide emulsion has a silver bromide content of 40 mol% or more.
5) With respect to the volume ratio of silver and binder in the photosensitive layer containing the silver chlorobromide emulsion at the center of the photosensitive layer, the photosensitive layer in the part closest to the transparent support surface or the part of the photosensitive layer farthest from the support. Item 5. The photosensitive material for producing a transparent conductive sheet according to any one of Items 1 to 4, wherein the volume ratio of silver and binder is small.
6) The volume ratio of silver to binder in the photosensitive layer containing the silver chlorobromide emulsion at the central portion of the photosensitive layer is 0.7 or more, and the photosensitive layer in the portion close to the transparent support surface or the portion farthest from the support Item 6. The photosensitive material for producing a transparent conductive sheet according to Item 5, wherein the volume ratio of silver to binder in the photosensitive layer is from 0.05 to 0.5.
7) One of the photosensitive layers having a small volume ratio of silver and binder contains a development inhibitor, and the other of the photosensitive layers having a small volume ratio of silver and binder does not contain a development inhibitor. 2. A photosensitive material for producing a transparent conductive sheet according to any one of the above.
8) The photosensitive material for producing a transparent conductive sheet according to Item 7, wherein the development inhibitor is a mercapto compound.
9) The photosensitive material for producing a transparent conductive sheet according to Item 7, wherein the development inhibitor is a compound that releases the development inhibitor by an oxidation-reduction reaction.

10) A transparent support comprising a conductive thin wire of developed silver by subjecting the photosensitive material for producing a conductive sheet according to any one of Items 1 and 3 to 9 to pattern exposure and then developing. A transparent conductive sheet characterized in that it is formed on one side.
11) Two transparent conductive sheets according to item 10 were used, and the conductive thin wires of each transparent conductive sheet were on the toucher side, and the conductive thin wires of the respective conductive patterns were laminated so that the conductive directions were orthogonal to each other. A capacitive touch panel characterized by the above.
12) The two transparent conductive sheets described in item 10 were used, and the transparent support of each transparent conductive sheet was placed on the toucher side, and the conductive fine lines of the respective conductive patterns were laminated so that the conductive directions were orthogonal to each other. A capacitive touch panel characterized by the above.
13) Using two transparent conductive sheets according to item 10, the conductive thin wires of each transparent conductive sheet face each other through an insulator other than the transparent support of the transparent conductive sheet, and the conductive thin wires of each conductive pattern A capacitive touch panel, which is laminated so that the conduction directions of the electrodes are orthogonal to each other.
14) In the touch panel according to any one of Items 11 to 13, the reflection chromaticity b ^* value of the conductive pattern measured from the toucher side is calculated from the conductive pattern on the side close to the toucher of the two conductive patterns ( a reflection chromaticity b ₁ ^* of the upper conductive pattern), when the reflection chromaticity b ₂ ^* farther conductive pattern on the touch's (lower conductive pattern), a reflection chromaticity b ₁ ^*, reflection chromaticity b ₂ An absolute value of a difference from ^* is less than 1.7 (| Δb ^* | = | b ₁ ^* −b ₂ ^* | <1.7).
15) The touch panel according to item 14, wherein the absolute value of the difference between the reflected chromaticity b ₁ ^* and the reflected chromaticity b ₂ ^* is 1.0 or more and less than 1.7.
16) The touch panel according to item 14, wherein the absolute value of the difference between the reflected chromaticity b ₁ ^* and the reflected chromaticity b ₂ ^* is less than 1.0.
17) The touch panel according to item 14, wherein the reflection chromaticity b ₁ ^* is −2.0 <b ₁ ^* ≦ 0.
18) The touch panel according to item 14, wherein the reflection chromaticity b ₂ ^* is −1.0 <b ₂ ^* ≦ 1.0.

19) A photosensitive material for producing a transparent conductive sheet, wherein the photosensitive material according to any one of items 1 to 9 has an asymmetric configuration with respect to a transparent support.
20) The photosensitive material for producing a transparent conductive sheet according to any one of Items 1 to 9, wherein the photosensitive material has an antihalation layer between the transparent support and the photosensitive layer.
21) A transparent support comprising a conductive thin wire of developed silver by carrying out pattern exposure on both sides of the photosensitive material for producing a conductive sheet according to any one of items 2 to 9, followed by development treatment A double-sided conductive pattern type transparent conductive sheet characterized by being formed on both sides.
22) In the double-sided conductive pattern type transparent conductive sheet according to item 21, the conduction direction of the conductive fine wire of the transparent conductive sheet on one side and the conduction direction of the conductive fine line of the transparent conductive sheet on the other side are: A double-sided conductive pattern type transparent conductive sheet, which is exposed so as to be orthogonal to each other.
23) A capacitive touch panel using the double-sided conductive pattern type transparent conductive sheet according to item 22.
24) In the capacitive touch panel using the double-sided conductive pattern type transparent conductive sheet of Item 23, the reflective chromaticity b ^* value of the conductive pattern measured from the toucher side is given to the toucher of the double-sided conductive pattern. side near the reflection chromaticity b ₁ ^* conductive pattern (front surface conductive pattern), when the reflection chromaticity b ₂ ^* farther conductive pattern on the touch's (back surface conductive pattern), the reflection chromaticity The absolute value of the difference between b ₁ ^* and reflection chromaticity b ₂ ^* is less than 1.7 (| Δb ^* | = | b ₁ ^* −b ₂ ^* | <1.7). Touch panel.
25) The touch panel according to item 24, wherein the absolute value of the difference between the reflected chromaticity b ₁ ^* and the reflected chromaticity b ₂ ^* is 1.0 or more and less than 1.7.
26) In the item 24, the absolute value of the difference between the reflected chromaticity b ₁ ^* and the reflected chromaticity b ₂ ^* is less than 1.0.
27) The touch panel as set forth in 24, wherein the reflection chromaticity b ₁ ^* is −2.0 <b ₁ ^* ≦ 0.
28) The touch panel according to item 24, wherein the reflection chromaticity b ₂ ^* is −1.0 <b ₂ ^* ≦ 1.0.

  The above transparent conductive sheet with improved color tone according to the present invention has improved color tone on the surface of the conductive material. Therefore, the transparent conductive sheet is not limited to the electrode material used for the capacitive touch panel described above, but human visibility and conductivity. It can be applied to all materials that are related to sex. For example, the transparent conductive sheet used for the resistive touch panel, the electromagnetic wave shielding sheet for shielding electromagnetic waves from the inside of the image display device, and the like are formed by patterning the electrodes of the present invention. The technique of the present invention can be used only by changing the pattern of the conductive thin wire. Further, a heating element sheet or an antistatic sheet can be prepared by adjusting the resistance value of the electrode of the present invention.

According to the present invention, a single-sided conductive sheet having a small difference in color between the front surface and the back surface of the conductive pattern, a single-sided conductive sheet having a conductive pattern surface near achromatic color, and further viewed from one side. Sometimes, a double-sided conductive sheet with little color unevenness can be obtained. In addition, by using the conductive sheet alone or in combination, a touch panel with small tint unevenness or near achromatic color can be obtained. Furthermore, while being excellent in color, it is excellent also in the stability of processing and manufacture, and a touch panel with stable quality can be obtained.
Moreover, when the transparent electrode sheet of the present invention is applied, a transparent conductive sheet, an electromagnetic wave shield sheet, a heating element sheet and an antistatic sheet used for a resistive film type touch panel excellent in color tone can be obtained.

It is a schematic cross section of the touch panel of the aspect of this invention. It is a schematic cross section of the touch panel of another aspect of the present invention. It is a schematic cross section of the touchscreen of another aspect of this invention. It is a schematic cross section of the photosensitive material for the conventional transparent conductive sheet manufacture. It is a schematic cross section of the photosensitive material for transparent conductive sheet manufacture of this invention. It is a schematic cross section of the photosensitive material for transparent double-sided conductive sheet manufacture of this invention. It is a conceptual diagram of the process which manufactures the transparent conductive sheet of this invention. It is a conceptual diagram of the process which manufactures the transparent double-sided conductive sheet of this invention. FIG. 3 is a perspective view of a laminate of an upper conductive sheet 11 and a lower conductive sheet 12 (the insulating layer 41 is omitted). It is a figure explaining the electroconductive grating | lattice part and connection part of the upper conductive sheet of FIG. It is a figure explaining the electroconductive grating | lattice part and connection part of the lower conductive sheet of FIG. It is a perspective view from the toucher side when an upper conductive sheet and a lower conductive sheet are laminated. It is a schematic diagram of the apparatus for performing double-sided exposure in FIG.8 (c).

Embodiments of a photosensitive material for producing a transparent conductive sheet according to the present invention, a transparent conductive sheet, a method for producing a transparent conductive sheet, and a capacitive touch panel using these transparent conductive sheets are shown in FIGS. This will be described with reference to FIG.
In this specification, the term “conductive material” is used as the term for the material that ensures conductivity, the term “conductor” is used for the term representing performance and function, the term “conducting layer” is used for the term representing the layer, and the sheet. The term “conductive sheet” is used as the term, the term “conductive thin wire” is used as the term representing the fine structure used, and the term “conductive pattern” is used as the term representing the structure of the fine line. When the application is specified, for example, the description of the application as an electrode for a touch panel is “electrode material”, “electrode”, “electrode layer”, “electrode sheet”, “electrode thin wire”, “electrode pattern”, respectively. "Can be used interchangeably with the term"".
Moreover, in this specification, "to" is used as the meaning including the numerical value described before and behind as a lower limit and an upper limit.

As described in the means for solving the problems, an object of the present invention is to solve problems such as uneven coloring and coloring of conductive sheets and touch panels.
Below, the relationship between the structure of a touch panel in which the electroconductive sheet of this invention (it is also hereafter called an electrode sheet) and a color difference are used is demonstrated using FIGS. 1-3.
FIG. 1 shows a configuration in which two electrode sheets are used when forming a touch panel, and FIG. 1 shows an example in which two transparent electrode sheets are laminated with the conductive thin wire side facing the toucher side. The case of laminating the two transparent conductive sheets with the transparent support side facing the toucher side (not shown) can be considered as in FIG. In the case of the touch panel configured as shown in FIG. 1, the toucher visually recognizes a region d1 in which the conductive thin lines of the upper electrode 11 are continuously arranged and a region d2 in which the conductive thin lines of the lower electrode 12 are continuously arranged. . At this time, if the upper electrode 11 and the lower electrode 12 use the same electrode sheet, the visible regions d1 and d2 will visually recognize the surface of the conductive thin wire of the same conductive sheet. I do not feel uneven taste. However, when the color is not neutral (when the absolute value of b ^* described later is a large value exceeding 2), there is a possibility that it may be considered as coloring of the touch panel, and there is a visible space between d1 and d2. In some cases (not shown), there is a problem of uneven coloring due to the contrast between the electrode surface and the space, so the reflected chromaticity of the electrode surface should be neutral or visually black. Is required. Moreover, when different transparent electrode sheets are used for the upper electrode and the lower electrode, there is a possibility that the colors of d1 and d2 may be different, and it is necessary to adjust so that the difference in color is not visually recognized.

FIG. 2 shows a configuration in which two electrode sheets are used when forming a touch panel, as in FIG. 1, but unlike FIG. 1, the conductive thin wire 21 of the upper electrode 11 and the conductive thin wire 22 of the lower electrode 12. And an adhesive layer that also serves as an insulating layer is provided between the conductive thin wire 21 and the conductive thin wire 22. In this case, even if the same transparent electrode sheet is used for the upper electrode 11 and the lower electrode 12, the touching person covers the surface of the conductive thin wire 21 on the transparent support 31 side in the region d1 and the conductive thin wire 22 in the region d2. The surface far from the transparent support 32 will be visually recognized, and the color difference between the transparent support side of the conductive thin wire and the surface far from the support (difference in b ^* value of reflection chromaticity) will be recognized. . Therefore, also in this configuration, when the same transparent electrode sheet is used for the upper electrode 11 and the lower electrode 12, the color difference (b ^{* of} reflection chromaticity) between the surface of the conductive thin wire on the side of the transparent support and the side far from the support ^. It is necessary to reduce the value difference. When different transparent electrode sheets are used for the upper electrode and the lower electrode, it is necessary to select a combination having a small color difference between d1 and d2. In any case, it is preferable that the reflection chromaticity of the electrode surface be close to visual black.

FIG. 1 and FIG. 2 are configured to use two electrode sheets when forming the touch panel, whereas FIG. 3 is a one-piece type in which the upper electrode 11 and the lower electrode 12 are formed on both surfaces of the transparent support. It is an example of the touch panel using the double-sided electrode. The color difference recognition in this example is similar to that in FIG. That is, even if the design of the upper electrode 11 and the lower electrode 12 is the same, the toucher has a surface far from the transparent support 32 of the conductive thin wire 21 in the region d1, and the transparent support 32 of the conductive thin wire 22 in the region d2. The surface on the side is visually recognized, and the color difference between the transparent support side of the conductive thin wire and the surface far from the support (difference in b ^* value of reflection chromaticity) is recognized. Therefore, in this aspect of the configuration, when the design of the upper electrode 11 and the lower electrode 12 is the same, the color difference (b ^* value of reflection chromaticity) of the surface of the conductive thin wire on the side of the transparent support and the side far from the support. It is necessary to reduce the difference). When the upper electrode and the lower electrode are designed differently, it is necessary to select a combination having a small color difference between d1 and d2. In any case, it is preferable that the reflection chromaticity of the electrode surface be close to visual black.

As described above, the present invention solves the problems related to visual recognition such as uneven coloring and coloring due to the difference in reflection chromaticity of the electrode mainly composed of conductive metal, makes the touch screen easy to see, and increases productivity. It is an invention aiming at providing a transparent electrode sheet that is excellent in resistance and has a low resistance and a large screen.
The reflection chromaticity in the present invention relates to a b ^* value that is a characteristic value defined in the L ^* a ^* b ^* color system described below. Specifically, it is the chromaticity related to the color b ^* value of the surface of the electrode seen when viewed from the toucher side when the touch panel is configured. The reflective chromaticity of the surface far from the transparent support (area d1 in FIGS. 1 and 3 and area d2 in FIG. 2) among the surfaces of the conductive thin wires constituting the electrode is b ₁ ^*, and the surface on the transparent support side The reflection chromaticity of the surface (region d2 in FIGS. 1 and 3 and region d1 in FIG. 2) is b ₂ ^* . Both are values measured from the toucher side.

The reflection chromaticity b ^* is a characteristic value defined by the L ^* a ^* b ^* color system. The L ^* a ^* b ^* color system is a color specification method defined by the International Commission on Illumination (CIE) in 1976, and the L ^* value, a ^* value, and b ^* value in the present invention are JIS- Z8729: A value obtained by measurement by the method defined in 1994. As a measuring method of JIS-Z8729, there are a measuring method by reflection and a measuring method by transmission. In the present invention, a value measured by reflection is used.
L ^* a ^* b ^* L ^* values in a color system, a ^* value, b ^* value, as is well known, L ^* value is brightness, and the a ^* value and b ^* value, hue and chroma Represents degrees. Specifically, if the a ^* value has a positive sign, it indicates a red hue, and if it has a negative sign, it indicates a green hue. If the b ^* value is positive, the hue is yellow, and if it is negative, the hue is blue. Further, for both the a ^* value and the b ^* value, the larger the absolute value, the larger the saturation of the color, and the brighter the color, and the smaller the absolute value, the smaller the saturation. Details of the measurement method are described in the Examples section.

In the present invention, the a ^* value varies little due to differences in electrode manufacturing conditions. On the other hand, the b ^* value varies more than the a ^* value due to differences in electrode manufacturing conditions. Specifically, the b ^* value tends to be visually recognized as color unevenness by changing from yellow to blue.
Specifically, in a system in which the amount of silver is increased to reduce resistance as in the present invention and the density of silver is increased in order to impart conductivity to a silver image formed by development, developed silver The color of the electrode surface far from the transparent support of the electrode tends to be blue, and the color of the electrode surface near the transparent support of the developed silver electrode tends to be yellowish.
The cause of the phenomenon that the color varies depending on the electrode formation conditions is considered as follows. In a system with a large amount of silver and a high silver density, development proceeds with a fresh developer composition on the surface side as the developer permeates from the surface of the photosensitive layer far from the transparent support, whereas the developer solution As the photosensitive layer penetrates toward the lower layer, development fatigue substances accumulate, and the development inhibitor contained in the developer is consumed in the surface layer. Is considered to progress. Along with this, it is presumed that differences occur in the shape and size of the developed silver filament on the upper layer side / lower layer side of the photosensitive material, and are observed as chromaticity differences. Due to such estimation, in the present invention, the modes described below are preferable.

Below, the reflection chromaticity b ^* value of the electrode surface desirable in the present invention will be described.
First, in FIG. 1, the b ^* absolute value (b ₁ ^* value or the absolute value of b ₂ ^* value) when the toucher visually recognizes the same surface of the same electrode as the upper electrode 11 and the lower electrode 12 is 1 Is preferably less than 7, more preferably 1 or less. By making it less than 1.7, it is possible to make it difficult to feel the color of the touch panel surface.
Further, in FIG. 1, the difference in reflection chromaticity when the upper electrode 11 and the lower electrode 12 are designed to be different from each other and electrodes having different surface colors is used is designed according to the description of FIGS. 2 and 3 below. It is preferable to do.

Next, as shown in FIG. 2 and FIG. 3, when observing the chromaticity of two surfaces of the same electrode wire (a surface closer to the support and a surface far from the support) or electrodes of different designs Is used, the absolute value of the difference in reflection chromaticity between the two surfaces (that is, the absolute value of the difference (Δb ^* ) between the reflection chromaticity b ₁ ^* and the reflection chromaticity b ₂ ^* ) has the following relationship: It is preferable to satisfy.
| Δb ^* | = | b ₁ ^* −b ₂ ^* | <1.7
Furthermore, the absolute value of Δb ^* is more preferably less than 1.0. If it is less than 1.7, it will be difficult to recognize color unevenness. Furthermore, as the b ₁ ^* of the absolute value is preferably ^{_{-2.0 <b 1 * ≦ 0,}} -1.5 <b 1 * ≦ -0.3 are more preferred, -1.0 <b ₁ ^* ≦ -0.5 is particularly preferred.
As the b ₂ ^* of the absolute value is preferably -1.0 <b ₂ ^* ≦ 1.0, more preferably ^{_{-0.7 <b 2 * ≦ 0.5,}} -0.5 <b 2 * ≦ 0.2 is particularly preferable The combination of b ₁ ^* and b ₂ ^* is preferably a combination of −2.0 <b ₁ ^* ≦ 0 and −1.0 <b ₂ ^* ≦ 1.0. A combination of 5 <b ₁ ^* ≦ −0.3 and −0.7 <b ₂ ^* ≦ 0.5 is more preferable, and −1.0 <b ₁ ^* ≦ −0.5 and −0.5 <b A combination of ₂ ^* ≦ 0.2 is particularly preferred.
By doing so, it is possible to eliminate the color unevenness on the electrode surface and to make it feel a black tone (neutral), and the visibility is further improved.
[Photosensitive materials and methods for forming them]

Below, the preferable aspect of each layer of the photosensitive layer for said reflection chromaticity adjustment is demonstrated.
The light-sensitive material for producing a transparent conductive sheet (also referred to as an electrode sheet) of the present invention is developed silver by subjecting a light-sensitive material formed with a light-sensitive layer containing a silver halide emulsion on a transparent support to pattern exposure and development. A photosensitive material for producing a transparent conductive sheet comprising a plurality of conductive thin wires, wherein the photosensitive layer comprises a plurality of photosensitive layers comprising emulsions having different halogen compositions, and a photosensitive layer comprising a silver halide emulsion. The photosensitive material is composed of at least one of a plurality of photosensitive layers having different silver densities and a plurality of photosensitive layers having different amounts of addition of a development inhibitor.
The photosensitive material will be described with reference to FIGS. FIG. 4 is a configuration diagram of a conventional photosensitive material, in which the photosensitive layer is illustrated as a single layer 51, whereas FIG. 5 showing the configuration of the present invention is a photosensitive layer 51 having three layers 52, 53, 54 as a laminate. Although FIG. 5 shows three photosensitive layers, in the present invention, it is sufficient that the number of layers is two or more, and it is not necessary to limit to three layers, but is a description for convenience of explanation.
In the present invention, at least one of the plurality of layers is a layer containing an emulsion having a halogen composition different from that of the other layers, or the photosensitive layer containing a silver halide emulsion has a silver density of other layers. Or a layer with a different amount of addition of the development inhibitor. Details of layers containing emulsions with different halogen compositions from other layers, layers having a silver density different from other layers of photosensitive layers containing silver halide emulsions, or multiple layers with different amounts of addition of development inhibitors This will be described separately below.

In another embodiment of the photosensitive material for producing a transparent conductive sheet of the present invention, a photosensitive layer containing a silver halide emulsion was formed on both surfaces (front surface and back surface) of the transparent support. A photosensitive material for producing a conductive sheet, wherein the photosensitive layer on the front side or the photosensitive layer on the back side comprises a plurality of photosensitive layers containing emulsions having different halogen compositions, or silver halide. A photosensitive material comprising a plurality of photosensitive layers having different silver densities of a photosensitive layer containing an emulsion. As illustrated in FIG. 6, the photosensitive material has an upper photosensitive material layer 50 and a lower photosensitive material layer 60 formed on both surfaces of the transparent support 32, and the upper photosensitive material layer 50 and the lower photosensitive material layer 60 in the upper part. The photosensitive layer 51 and the lower photosensitive layer 61 are each formed of a plurality of photosensitive layers. In FIG. 6, at least one of the six photosensitive layers in total is a layer containing an emulsion having a different halogen composition from the other layers, or the silver density of the photosensitive layer containing a silver halide emulsion is other than It is characterized in that it is a layer different from the layer or at least one of a plurality of photosensitive layers having different development inhibitor addition amounts.
Next, materials constituting the photosensitive material for producing the transparent conductive sheet of the present invention will be described.

(Transparent support)
As the transparent support used in the light-sensitive material of the present invention, a plastic film, a plastic plate, a glass plate and the like can be used, and a plastic film is preferable.
Examples of plastic film materials include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN); polyolefins such as polyethylene (PE), polypropylene (PP) and polystyrene; polyvinyl chloride and polyvinylidene chloride Other vinyl chloride resins such as polyether ether ketone (PEEK), polysulfone (PSF), polyether sulfone (PES), polycarbonate (PC), polyamide, polyimide, acrylic resin, triacetyl cellulose (TAC), etc. Can be used.
The plastic film in the present invention can be used as a single layer, but can also be used as a multilayer film in which two or more layers are combined.
As the support, PET (258 ° C.), PEN (269 ° C.), PE (135 ° C.), PP (163 ° C.), polystyrene (230 ° C.), polyvinyl chloride (180 ° C.), polyvinylidene chloride (212 ° C.) A plastic film having a melting point of about 290 ° C. or less such as TAC (290 ° C.) is preferable, and PET is particularly preferable. Figures in parentheses are melting points. The transmittance of the film is preferably 85% to 100%.
The thickness of the transparent support film can be arbitrarily selected in the range of 50 μm or more and 500 μm or less. In particular, in the case where it also functions as a touch surface in addition to the function of the support of the transparent conductive sheet, it can be designed with a thickness exceeding 500 μm. When a photosensitive layer containing a silver halide emulsion is provided on a transparent support by a coating method, the thickness of the film is preferably 50 μm or more and 250 μm or less from the viewpoint of production.

[Photosensitive layer containing silver halide emulsion]
Next, the photosensitive layers 51 and 61 containing silver halide emulsion will be described. In order to use developed silver as a conductive material, the type of photosensitive material and the type of development processing are selected from the following three methods. can do. (1) A method in which a photosensitive silver halide black-and-white photosensitive material not containing physical development nuclei is chemically or thermally developed to form a metallic silver portion on the photosensitive material. (2) A system 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 that does not contain physical development nuclei and an image-receiving sheet having a non-photosensitive layer that contains physical development nuclei are overlaid and diffused and transferred to develop a non-photosensitive image-receiving sheet. Forming on top.

The mode (1) is a black-and-white development type, and a light-transmitting conductive film such as a light-transmitting electromagnetic wave shielding film is formed on the photosensitive material. The developed silver obtained is chemically developed silver or heat developed silver, and is a filament with a high specific surface. Furthermore, when a subsequent process of plating or physical development is provided, it is a highly active and preferable method.
In the above aspect (2), in the exposed portion, the silver halide grains close to the physical development nucleus are dissolved and deposited on the development nucleus, whereby a light-transmitting electromagnetic wave shielding film or a light-transmitting conductive film is formed on the photosensitive material. A translucent conductive film such as is formed. This is also a black and white development type. Although the developing action is precipitation on physical development nuclei, it is highly active, but the developed silver obtained has a spherical shape 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 electromagnetic wave shielding film or a light transmitting conductive film is formed on the image receiving sheet. A translucent conductive film such as a film is formed. This is a so-called two-sheet 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 referred to here have the same meanings as are commonly used in the art, and a general textbook of photographic chemistry such as Shinichi Kikuchi, “Photochemistry” (Kyoritsu) Published by publisher), C.I. E. K. It is described in “The Theory of Photographic Process, 4th ed.” Edited by Mees (Mcmillan, 1977). Further, for example, the techniques described in JP-A Nos. 2004-184893, 2004-334077, and 2005-010752 can be referred to.

Among the above methods (1) to (3), since the method (1) does not have a physical development nucleus in the photosensitive layer before development and is not a two-sheet diffusion transfer method, the method (1) Is the most convenient and stable treatment, and is preferable for producing the transparent conductive sheet of the present invention. In the following, the description of the method (1) will be described. However, when other methods are used, it is possible to refer to the document described in the upper part. Note that “dissolved physical development” is not a development method unique to the method (2) but a development method that can also be used in the method (1).
(Silver halide emulsion)

The halogen element contained in the silver halide emulsion of the present invention may be any of chlorine, bromine, iodine and fluorine, or a combination thereof. For example, silver halides mainly composed of silver chloride, silver bromide and silver iodide are preferably used, and silver halides mainly composed of silver bromide and silver chloride are preferably used. Silver chlorobromide, silver iodochlorobromide and silver iodobromide are also preferably used.
The silver halide emulsion used in the photosensitive layers 51 and 61 of the present invention is a silver chlorobromide emulsion. However, the halogen distribution in the photosensitive layer is not uniform, and the distribution in the layer is biased. Is preferred. Specifically, the silver bromide content in the silver chlorobromide emulsion is such that the odor of the photosensitive layer at the portion closest to the transparent support surface relative to the central portion of the photosensitive layer or the photosensitive layer farthest from the support. It is preferable that the silver halide content is as high as 5 mol% or more. Further, if it is increased by 10% or more, the effect of improving chromaticity can be further increased.
In the present invention, the “central portion” refers to a central portion based on thickness, and is defined as a layer that occupies 20% before and after the center.
The silver bromide content of the silver chlorobromide emulsion at the center of the photosensitive layer is 30 mol% or less, and the chlorobromide of the photosensitive layer at the portion closest to the transparent support surface or the photosensitive layer furthest from the support. The silver bromide content of the silver emulsion is preferably 30 mol% or more, more preferably 45 mol% or more, and particularly preferably 65 mol% or more.

The volume ratio of silver and binder in the photosensitive layers 51 and 61 is not uniform in the photosensitive layer, and it is preferable that the volume ratio distribution is biased in the layers. Specifically, the silver layer of the photosensitive layer containing the silver chlorobromide emulsion in the central portion is close to the transparent support surface or the silver layer of the photosensitive layer furthest from the support with respect to the volume ratio of silver to binder. It is preferable to reduce the volume ratio of the binder.
The volume ratio of silver and binder in the photosensitive layer containing the silver chlorobromide emulsion at the center of the photosensitive layer is 0.7 or more, and the photosensitive layer in the part closest to the transparent support surface or the part farthest from the support is exposed. The volume ratio of silver and binder in the layer is more preferably 0.05 or more and 0.5 or less.
The volume ratio of silver and binder in the photosensitive layer containing the silver chlorobromide emulsion at the center of the photosensitive layer is 1.0 or more, and the photosensitive layer in the portion closest to the transparent support surface or the portion farthest from the support is exposed. The volume ratio of silver and binder in the layer is more preferably 0.1 or more and 0.4 or less.

Furthermore, the volume ratio of silver to binder in the silver chlorobromide emulsion in which the silver bromide content is high relative to the central portion of the photosensitive layer is preferably lower than the volume ratio of the central portion. The volume ratio of silver and binder in the photosensitive layer of the part is 0.7 or more, and the volume ratio of silver and binder in the layer having a high silver bromide content is 0.05 or more and 0.5 or less. More preferred. Further, the volume ratio of silver to binder in the central photosensitive layer is 1.0 or more, and the volume ratio of silver to binder in the layer having a high silver bromide content is from 0.1 to 0.4. It is particularly preferable that
In the present invention, the silver density, that is, the volume ratio of silver and binder, is calculated or measured only in each photosensitive layer, and does not contain a silver halide emulsion such as a protective layer, an antihalation layer, and an easy adhesion layer. The component of is not included. Further, the volume of silver is obtained by calculating or measuring the amount of silver applied and converted to a volume having a specific gravity of 10.5, and the volume of the binder is obtained by calculating whether the solid content other than silver is calculated. 34 is converted into a volume. When the ratio of the latex polymer contained in the layer exceeds 20% by mass with respect to gelatin, the volume of the latex polymer is calculated using the specific gravity of the latex polymer.

In the present invention, the thickness of the photosensitive layer is described by the amount of silver applied. The thickness itself can be obtained by the above conversion method based on the amount of silver applied and the amount of additives such as a binder. Specifically, the coated silver amount of the upper photosensitive layer 51 (the same applies to the lower photosensitive layer 61) is preferably 4 g / m ² or more and 20 g / m ² or less, and more preferably 5 g / m ² or more and 20 g / m ² or less. When it is 4 g / m ² or more and 20 g / m ² or less, it is possible to form a coating film and a conductive sheet having low resistance and stable production. The coated silver amount of the upper photosensitive layer 51 and the lower photosensitive layer 61 may be the same coating amount or different coating amounts as long as they are within the above range.
The film thickness of the layer having a high silver bromide content and the photosensitive layer having a small volume ratio of silver and binder is preferably 10% or more and 40% or less, more preferably 15% or more with respect to the total film thickness of the photosensitive layers 51 and 61. 30% or less is more preferable.

  In the present invention, it is preferable to include a small amount of silver iodide in order to suppress fogging, and the silver iodide content is in a range not exceeding 1.5 mol% per mol of silver halide emulsion. It is preferable. By setting the silver iodide content in a range not exceeding 1.5 mol%, fogging can be prevented and the pressure property can be improved. A more preferred silver iodide content is 1 mol% or less per mole of silver halide emulsion. In the present invention, 0.5 mol% to 1 mol% of silver iodide is included, but in order to avoid complicated description, the display of silver iodide is omitted and it is expressed as silver chlorobromide.

  Regarding the average grain size of silver halide, the shape and dispersion degree of silver halide grains, and the coefficient of variation, reference can be made to the descriptions in paragraphs 36 and 37 of JP-A-2009-188360. Regarding the use of metal compounds belonging to Group VIII and VIIB, such as rhodium compounds and iridium compounds, and palladium compounds, which are used for stabilizing and enhancing the sensitivity of silver halide emulsions, paragraph 39 of JP-A-2009-188360. -The description of paragraph 42 can be referred to. Further, regarding chemical sensitization, reference can be made to the technical description in paragraph 43 of JP2009-188360A.

(binder)
In the photosensitive layer containing a silver halide emulsion, a binder is used for the purpose of uniformly dispersing silver salt grains and assisting the adhesion between the emulsion layer and the support. Examples of the binder include polysaccharides such as gelatin, carrageenan, polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), starch, cellulose and derivatives thereof, polyethylene oxide, polysaccharides, polyvinylamine, chitosan, polylysine, and polyacrylic acid. , Polyalginic acid, polyhyaluronic acid, carboxycellulose, gum arabic, sodium alginate and the like, and gelatin is preferred.
As gelatin, lime-processed gelatin or acid-processed gelatin may be used, and gelatin hydrolyzate, gelatin enzyme decomposition product, and other gelatins modified with amino groups and carboxyl groups (phthalated gelatin, acetylated gelatin) are used. can do.
Moreover, latex can also be used as a binder. Here, as the latex, the polymer latex described in JP-A-2-103536, page 18, lower left column, lines 12 to 20 can be preferably used.
(Development inhibitor)

In the present invention, a development inhibitor such as sodium bromide or potassium bromide is included in the development processing solution described later to control the development speed so that developed silver is obtained only in the exposed area. However, in a system having a large amount of silver as in the present invention, it is expected that a development inhibitory substance is consumed as the developer permeates from the surface of the photosensitive layer, causing a phenomenon in which physical development proceeds. Therefore, it is conceivable to include a development inhibitor on the lower layer side of the photosensitive layer.
Examples of the development inhibitor used in the photosensitive layer include organic mercapto compounds, unsaturated 5-membered heterocycles or 6-membered heterocycles having nitrogen atoms such as pyrrole ring, imidazole ring, pyrazole ring, pyrimidine ring, pyridazine ring, pyrazine ring. A ring can be mentioned. In order for these compounds to remain in a specific layer and be activated by a permeated developer, a) a relatively low molecular weight compound that remains in a specific layer due to the interaction with the emulsion. A compound that is activated by alkali in the solution, b) a compound that has a large molecular weight and is difficult to move, but reacts with the alkali to release a low-molecular inhibitory compound, and c) a molecular weight that is difficult to move but is an oxidation product in the treatment liquid. Examples include compounds that react to release low-molecular inhibitory compounds.

  Examples of the a) include mercapto compounds having a skeleton of a 5-membered ring azole having an NH structure or a 6-membered ring azine having an NH structure. As the mercapto compound, compounds described in paragraph 34 to paragraph 102 of JP-A No. 2007-116137 can be used, preferably 39 compounds described in paragraph 60 to paragraph 65, and paragraphs 90 to 93. And the three compounds described in paragraph 101. Among these compounds, compounds that can be particularly preferably used are the compounds described in paragraphs 60, 65, and 101.

As an example of the above b), a compound group described in JP-A-2-285344, which has an adsorption ability for silver halide grains but is protected so as not to exhibit the adsorption ability before development, that is, development. Mention may be made of compounds known as inhibitor precursors. As these compounds, compounds represented by (1) to (33) of JP-A-2-285344 can be used.
Examples of the above c) include redox compounds described in Japanese Patent No. 4035268, which can release a low-molecular development inhibitor when oxidized. As these compounds, compounds represented by the general formulas (1) to (3) described in Japanese Patent No. 4035268 are preferable, hydrazine derivatives are more preferable, and specifically R-1 to R-70 hydrazines. Derivatives are particularly preferred.

  The development inhibiting compound of the present invention contained in the photosensitive layer is easier to adjust the color when it is not uniformly contained in the photosensitive layer. It is preferable that the content of the development inhibiting compound in the photosensitive layer is high in the photosensitive layer (u layer) on the side close to the transparent support. Furthermore, it is more preferable to include the mercapto compound only in the photosensitive layer on the transparent support side, in other words, to localize the development inhibitor in the layer farthest from the photosensitive layer surface in contact with the developer. Alternatively, it is preferable to sequentially increase the concentration of the development inhibitor toward the layer far from the photosensitive layer surface in contact with the developer.

  The amount of the development inhibiting compound contained in at least one of the plurality of photosensitive layers of the present invention is the amount of addition itself in the case of a), and the amount of the released inhibitor in the cases of b) and c), It is preferably 0.1 mg or more and 15 mg or less, more preferably 0.5 mg or more and 10 mg or less with respect to 1 g (gram) of silver in the silver halide emulsion contained in the same layer as the development inhibiting compound. It is particularly preferably 1 mg or more and 6 mg or less. It is easy to adjust the color when it is in the range of 0.1 mg or more and 15 mg or less.

[Other layer structure]
A protective layer (not shown) may be provided on the photosensitive layer of the present invention. In the present embodiment, the “protective layer” means a layer composed of a binder such as gelatin or a high molecular polymer, and is formed on a photosensitive layer having photosensitivity in order to exhibit an effect of preventing scratches or improving mechanical properties. The 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.
The photosensitive material of the present invention preferably has an antihalation layer between the transparent support and the photosensitive layer. In particular, the photosensitive material having photosensitive layers on both sides of the transparent support of the present invention is preferably provided with antihalation layers 57 and 67 between the transparent support and the respective photosensitive layers.
When a photosensitive material having photosensitive layers on both sides is subjected to simultaneous exposure as shown in FIG. 13, unnecessary exposure occurs due to light that cannot be completely absorbed by each photosensitive layer, and an image of the opposite surface appears in a desired pattern. Because it does. It is preferable to provide an antihalation layer having an appropriate density in order to suppress such image transfer.
Regarding the material used for the antihalation layer and the method of using the same, the description in paragraphs 29 to 32 of JP-A-2009-188360 can be referred to. The optical density of the antihalation layer varies depending on the intensity and wavelength of light to be exposed, but is preferably about 0.5 to 3.0.
[Other additives]

  The photosensitive layer, the pressure-sensitive adhesive layer, and the undercoat layer of the present invention may contain a dye for adjusting the color. In addition, a dye layer may be provided between the photosensitive layer of the present invention and the transparent support, or between the photosensitive layer and the undercoat layer. Regarding the dyes used in these layers and the method of using them, the description in paragraphs 29 to 32 of JP-A-2009-188360 can be referred to.

The solvent used for forming the photosensitive layer of the present invention is not particularly limited. For example, water, organic solvents (for example, alcohols such as methanol, ketones such as acetone, amides such as formamide, dimethyl sulfoxide, etc. Sulphoxides such as, esters such as ethyl acetate, ethers, etc.), ionic liquids, and mixed solvents thereof.
The content of the solvent used in the photosensitive layer is in the range of 30 to 90% by mass and preferably in the range of 50 to 80% by mass with respect to the total mass of the silver salt and binder contained in the photosensitive layer. .

There are no particular restrictions on the various additives used in the present embodiment, and known ones can be preferably used. For example, various matting agents can be used, and thereby the surface roughness can be controlled. The matting agent is preferably made of a material that remains after development processing and does not impair the transparency and dissolves in the processing step.
[Method for forming photosensitive material]
In order to form the above-described photosensitive material, a coating method or a printing method can be used. However, it is preferable to use a coating method from the viewpoint of stable production. Examples of the coating method include a bar coating method, a reverse coating method, a gravure coating method, a die coating method, and a roll coating method.
[Method for producing transparent conductive sheet (also referred to as electrode sheet)]

  Next, a process for forming a transparent conductive sheet using the above photosensitive material will be described with reference to FIGS. 7B is a diagram in which a photosensitive material is provided on one side of the transparent support 32 in FIG. 4 or FIG. 5, and FIG. 8B is a diagram in which the photosensitive material is provided on both sides of the transparent support 32 in FIG. It is a figure. In the following description, FIG. 7 will be used for explanation, and only when there are matters specific to the double-sided photosensitive material, FIG.

〔exposure〕
The photosensitive material having the photosensitive layer 51 provided on the transparent support 32 described so far is exposed, and the transparent conductive sheet of the present invention is produced by development processing in the next step. That is, the photosensitive material for producing a conductive sheet described above is subjected to pattern exposure, and then developed to form a transparent conductive pattern (also referred to as an electrode) made of developed silver conductive fine wires on one side of the transparent support, Alternatively, pattern exposure is performed on both sides of the photosensitive material for producing a conductive sheet described above, and then development processing is performed, thereby forming transparent electrodes made of conductive thin wires of developed silver on both sides of the transparent support. Alternatively, a double-sided electrode type transparent conductive sheet is manufactured.
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.
The exposure method is also preferably surface exposure through a mask. Further, it is also preferable that the scanning exposure is a direct writing, not through a mask.
When a double-sided photosensitive material is used, exposure can be performed with a mask attached to both sides of the photosensitive material 05 as shown in FIG. In this case, it is desirable that the masks 110 and 120 are adjusted so as to be a uniform pattern when the conductive pattern formed by the development process is seen through. Specifically, in the double-sided electrode type transparent conductive sheet, the conduction direction of the conductive fine wire of the transparent conductive sheet on one side and the conduction direction of the conductive fine line of the transparent conductive sheet on the other side are orthogonal to each other. It is preferable that the exposure is performed so as to be arranged.
In the exposed photosensitive material, an emulsion pattern (photosensitive nucleus pattern) is formed in the form of a mask image as shown in 131 and 141 in FIGS. 7C and 8C.

[Development processing, fixing processing, water washing processing]
In this embodiment, after the photosensitive layer is exposed, development processing is performed as shown in FIGS. 7D and 8D, and the exposed silver halide portion forms a silver thin line 151, and exposure is performed. The unexposed portion 152 is subjected to a fixing process after development to remove unexposed silver halide to form a transparent film.
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 a PQ developer, MQ developer, MAA developer and the like can also be used. Commercially available products include, for example, CN-16, CR-56, CP45X, and FD prescribed by FUJIFILM Corporation. -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 with respect to the processing of the photosensitive material 122, more preferably 500 ml / ^{m 2} or less, 300 ml / ^{m 2} or less is particularly preferred.
The photosensitive material 122 that has been subjected to development and fixing processing is preferably subjected to water washing processing and stabilization processing. In the water washing treatment or the 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 (conductive pattern) after the development treatment is preferably a content of 50% by mass or more with respect to the mass of silver contained in the exposed portion before the exposure, and 80 mass. % Or more is more preferable. 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 doping of the aforementioned rhodium ions and iridium ions, and containing a polyethylene oxide derivative in the developing solution.

It is preferable to carry out the film hardening process by immersing the film in a hardening agent after developing the photosensitive layer. Examples of the hardener include dialdehydes such as potassium alum, glutaraldehyde, adipaldehyde, 2,3-dihydroxy-1,4-dioxane, and those described in JP-A-2-141279 such as boric acid. be able to.
A transparent conductive sheet is obtained through the above steps. The surface resistance of the obtained transparent conductive sheet is 0.1 to 100 ohm / sq. In the range of 1 to 50 ohm / sq. Is more preferably in the range of 1 to 10 ohm / sq. It is more preferable that it is in the range.
Moreover, the volume low efficiency of the obtained transparent conductive sheet is preferably 160 μΩcm or less, more preferably in the range of 1.6 to 16 μΩcm, and in the range of 1.6 to 10 μΩcm. It is more preferable.
[Auxiliary processing after development processing]

Subsequent to the above development processing, the following processing can be performed for the purpose of improving the conductivity.
(Calendar processing)
In the manufacturing method of the present embodiment, a smoothing process is performed on the transparent conductive sheet that has been developed. This significantly increases the conductivity of the transparent conductive sheet. The smoothing process can be performed by, for example, a calendar roll. The calendar roll usually consists of a pair of rolls. Hereinafter, the smoothing process using the calendar roll is referred to as a calendar process.
As a roll used for the calendar process, a plastic roll or a metal roll such as epoxy, polyimide, polyamide, polyimide amide or the like is used. In particular, when emulsion layers are provided on both sides, it is preferable to treat with metal rolls. When an emulsion layer is provided on one side, a combination of a metal roll and a plastic roll can be used from the viewpoint of preventing wrinkles. The upper limit of the linear pressure is 1960 N / cm (200 kgf / cm), converted to surface pressure of 699.4 kgf / cm ² or more, more preferably 2940 N / cm (300 kgf / cm, converted to surface pressure, 935.8 kgf / cm). ² ) or more. The upper limit of the linear pressure is 6880 N / cm (700 kgf / cm) or less.
The application temperature of the smoothing treatment represented by the calender roll is preferably 10 ° C. (no temperature control) to 100 ° C., and the more preferable temperature varies depending on the line density and shape of the metal mesh pattern and metal wiring pattern, and the binder type. , Approximately 10 ° C. (no temperature control) to 50 ° C.

(Treatment in contact with steam)
In the manufacturing method of the present embodiment, the smoothed conductive pattern may be brought into contact with steam (steam contact process). In this vapor contact step, the smoothed transparent conductive sheet is brought into contact with superheated steam, and the smoothed conductive pattern 108 is brought into contact with pressurized steam (pressurized saturated steam); There is. Thereby, electroconductivity and transparency can be improved simply in a short time. It is considered that a part of the water-soluble binder is removed and the bonding sites between the metals (conductive substances) are increased.

(Washing treatment)
In the manufacturing method of this Embodiment, it is preferable to wash with water after making a transparent conductive sheet contact superheated steam or pressurized steam. By washing with water after the steam contact treatment, the binder dissolved or brittle with superheated steam or pressurized steam can be washed away, whereby the conductivity can be improved.

(Plating treatment)
In the present embodiment, the above-described smoothing process may be performed, or a plating process may be performed on the transparent conductive sheet. By plating, the surface resistance can be further reduced and the conductivity can be increased. The smoothing process may be performed either before or after the plating process. However, when the smoothing process is performed before the plating process, the plating process becomes efficient and a uniform plating layer is formed. The plating treatment may be electrolytic plating or electroless plating. Moreover, the metal which has sufficient electroconductivity is preferable as the constituent material of a plating layer, and copper is preferable.

(Oxidation treatment)
In the present embodiment, it is preferable to subject the transparent conductive sheet after the development treatment and the conductive metal portion formed by the plating treatment to an 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.

The conductive sheet made of conductive thin wires formed through the above process is a patterned conductive pattern made of a plurality of conductive thin wires.
The transparent conductive sheet having the conductive pattern of the present invention can be used for various purposes such as antistatic, heating element, electromagnetic wave shield, and electrode material, and more preferably used for a capacitive touch panel.
Hereinafter, the conductive sheet having conductive thin wires formed and patterned on the transparent support of the present invention will be described in relation to a capacitive touch panel in which the transparent conductive sheet of the present invention is preferably used.
[Transparent conductive sheet and touch panel using it]

Next, with respect to a conductive pattern (hereinafter, mainly referred to as an electrode or a patterned electrode in the context of a touch panel) formed of a conductive thin wire formed on the transparent support of the present invention, the transparent conductive sheet ( Hereinafter, the description will be made in relation to a capacitive touch panel in which an electrode sheet is mainly used. In a conventional capacitive touch panel, an ITO thin film, which is a transparent electrode material, has been used as a bar electrode as an electrode material. However, in the present invention, a combination of conductive thin wires using a material having a resistance lower than that of ITO is used. Since an electrode is formed, this is called a patterned electrode.
The touch panel illustrated in FIGS. 1 to 3 is a touch panel using the transparent electrode sheet manufactured as described above, FIGS. 1 and 2 are embodiments using two transparent electrode sheets, and FIG. 3 is a transparent support. The touch panel of the aspect which has an electrode on both surfaces is represented. Hereinafter, FIG. 1 will be described as an example.
The touch panel of FIG. 1 includes a transparent support 30 for the touch surface, an upper electrode 11, and a lower electrode 12 laminated in this order from the toucher side, and FIG. 9 is a perspective view of the upper electrode 11 and the lower electrode 12 of this touch panel. . The plurality of electrodes constituting the upper electrode 11 and the lower electrode 12 are each composed of a plurality of conductive grid portions 14A and 14B that sense capacitance, and a conductive connection portion 16A that connects the grid and the grid. The lead wires 18A and 18B connect these electrodes and the external control unit. In FIG. 9, the conductive lattice portion is displayed like a mesh, but a pattern (called a diamond pattern) in which rhombus-like transparent conductive films such as ITO are combined may be used. The number of electrodes of the upper electrode 11 and the lower electrode 12 and the number of conductive lattice portions can be changed according to the size of the panel and the ease of control.
In FIG. 9, the electrodes of the upper electrode 11 and the lower electrode 12 are arranged so as to be substantially orthogonal. This is because the orthogonal arrangement facilitates uniformizing the electrode pattern when the two electrodes are seen through from one side, as described below, and is excellent in visibility.
In the present invention, two transparent electrode sheets are used, and the conductive thin wires of each transparent electrode sheet are on the toucher side, and the conductive thin wires of each electrode are laminated so that the conduction directions of the conductive thin wires are orthogonal to each other. A capacitive touch panel is preferred.
In addition, the electrostatic capacity system in which two transparent electrode sheets are used, and the transparent support of each transparent electrode sheet is on the toucher side, and the conductive thin wires of each electrode are stacked so that the conduction directions thereof are orthogonal to each other The touch panel is preferable.
Further, two transparent electrode sheets are used, and the conductive thin wires of each transparent electrode sheet face each other through an insulator other than the transparent support of the transparent electrode sheet, and the conductive directions of the conductive thin wires of each electrode are orthogonal to each other. A capacitive touch panel in such a stacked manner is preferable.
Moreover, in the double-sided electrode type transparent electrode sheet of the present invention, the conduction direction of the conductive fine wire of the transparent electrode sheet on one side and the conduction direction of the conductive fine wire of the transparent electrode sheet on the other side are orthogonal to each other. A capacitive touch panel using a double-sided electrode type transparent electrode sheet that is exposed so as to be arranged is preferable.
10 and 11 are views showing the conductive grid portions 14A and 14B of the upper electrode 11 and the lower electrode 12 and the conductive connection portions 16A and 16B connecting the grid and the grid, respectively, in FIG. The conductive lattice portion 14A is disposed around the square lattice composed of the conductive thin wires 21, the dummy thin wires 19 including a number of short lines, and the conductive lattice portion 14A connecting the conductive lattice portion 14A in the electrode direction. The connecting portion 16A is described. In order to prevent the electrode from functioning due to an unexpected disconnection failure, the conductive connecting portion 16A is connected not by a single thin line but by a plurality of thin lines.
The conductive grid portions 14B and 16B in FIG. 11 can be described in the same manner as the conductive grid portions 14A and 16A.

FIG. 12 shows how the electrode lines appear when FIG. 9 is seen through from the toucher side. FIG. 12 using the upper electrode 11 and the lower electrode 12 of the present invention has a uniform square lattice and can constitute a panel that is easy to visually recognize. In FIG. 12, the lattice appears to be formed in a straight line, but there are a straight line part and a part composed of two short lines. This is shown in an enlarged view of the circled portion in FIG. 12, and the solid line portion on the left side represents a part of the conductive thin wire 21 of the conductive grid portion 14A of the upper electrode sheet. (21) is a dummy fine wire around the conductive grid portion 14A. Similarly, the dotted line portion on the right side represents a part of the conductive thin wire 22 of the conductive lattice portion 14B of the lower electrode sheet, and the dotted line 19 (22) is a dummy thin wire around the conductive lattice portion 14B. In this way, even though it looks visually as a single straight line, the conductive thin wires 21 and 22 are not actually connected, and the dummy thin wire 19 is not connected.
As can be understood from the above, the dummy thin wire 19 used in the present invention is a thin wire used for improving visibility, and as described in FIGS. 10 and 11, the dummy thin wire is at both ends of the long wire of the square lattice. It is formed on the extension line of the part and is disconnected so as not to be electrically connected to the conductive grid part. The length of the dummy thin line is ½ or less of the side length of the unit cell of the electrode portion.
10 to 12 indicate that the double-sided electrode sheet is cut at this position, and the cross-sectional view at this position is the touch panel of FIGS.

Below, the upper electrode 11 is taken for an example, and the detail of an electrode is demonstrated. The ITO diamond pattern, which has been used to form conventional electrodes, is difficult to apply to large screens because of its high ITO resistance value. In the present invention, the diamond portion is formed of a mesh or lattice made of low-resistance fine wires, and the diamond pattern is low. Resistance and screen brightness are guaranteed. Hereinafter, the description will be made using a square lattice, but this does not preclude the use of a rectangular lattice or the like.
The line width of the thin conductive wires forming the conductive lattice portion is preferably 1 μm or more and 10 μm or less, and more preferably 1 μm or more and 6 μm or less. When the thickness is in the range of 1 μm or more and 10 μm or less, a low-resistance electrode can be formed relatively easily.
The thickness of the conductive thin wires forming the conductive lattice portion is preferably 0.1 μm or more and 1.5 μm or less, and more preferably 0.2 μm or more and 0.8 μm. When the thickness is in the range of 0.1 μm or more and 1.5 μm or less, a low-resistance electrode that is excellent in durability can be formed relatively easily.

  The length of one side of the conductive grid portions 14A and 14B of the present invention is preferably 3 to 10 mm, and more preferably 4 to 6 mm. If the length of one side is 3 to 10 mm, it is difficult to cause problems such as a possibility of detection failure due to insufficient sensing capacitance and a decrease in position detection accuracy. From the same viewpoint, the length of one side of the unit cell constituting the conductive lattice part is preferably 50 to 500 μm, and more preferably 150 to 300 μm. When the length of the side of the unit cell is in the above range, the transparency can be further kept good, and the display can be visually recognized without a sense of incongruity when attached to the front surface of the display device.

Note that the upper and lower electrodes of the touch panel in FIG. 9 are substantially orthogonal in conduction direction, but can be set to any angle as long as there is no hindrance in determining the coordinates of the touch position.
Furthermore, the direction of the conductive thin wires constituting the square lattice illustrated in FIGS. 10 and 11 is 45 ° with respect to the X and Y axes. The touch panel of the present invention has a feature that moire does not easily occur when the X and Y directions of the panel are bonded as the electrode axis direction of the image display device.

  The electrode sheet composed of the above patterned electrodes can significantly reduce the electric resistance as compared with a structure in which one electrode is formed by one ITO film. Therefore, when the electrode sheet of the present invention is used for, for example, a projected capacitive touch panel, the response speed can be increased and the touch panel can be increased in size.

  In addition, this invention can be used in combination with the technique of the publication gazette and international publication pamphlet of following Table 1 suitably. Notations such as “JP,” “Gazette” and “No. Pamphlet” are omitted. Japanese publications are displayed with a hyphen after the year, as in 2004-221564, and international pamphlets are displayed with a slash after the year, as in 2006/001461.

  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. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below.

Example 1
Hereinafter, a transparent conductive sheet (also referred to as an electrode sheet) having an electrode (also referred to as a conductive pattern) on one side of the transparent support was prepared and evaluated.
(Preparation of emulsion)
To the following 1 liquid maintained at 38 ° C. and pH 4.5, an amount corresponding to 90% of each of the following 2 and 3 liquids was added simultaneously over 20 minutes with stirring to form 0.16 μm core particles. Subsequently, the following 4 liquid and 5 liquid were added over 8 minutes, and the remaining 10% of the following 2 liquid and 3 liquid were further added over 2 minutes to grow to 0.21 μm. Further, 0.10 g of potassium iodide was added and ripened for 5 minutes to complete the grain formation.

1 liquid:
750 ml of water
Gelatin (phthalated gelatin) 8g
Sodium chloride 3g
1,3-Dimethylimidazolidine-2-thione 20mg
Sodium benzenethiosulfonate 10mg
Citric acid 0.7g
Two liquids:
300 ml of water
150 g silver nitrate
3 liquids:
300 ml of water
Sodium chloride 38g
Potassium bromide 32g
Hexachloroiridium (III) potassium (0.005% KCl 20% aqueous solution) 5 ml
Ammonium hexachlororhodate (0.001% NaCl 20% aqueous solution) 7 ml
4 liquids:
100ml water
Silver nitrate 50g
5 liquids:
100ml water
Sodium chloride 13g
Potassium bromide 11g
Yellow blood salt 5mg

  Then, it washed with water by the flocculation method according to a conventional method. Specifically, the temperature was lowered to 35 ° C., 3 liters of distilled water was added, and then the pH was lowered using sulfuric acid until the silver halide precipitated (the pH was in the range of 3.6 ± 0.2). . Next, about 3 liters of the supernatant was removed (first water washing). Further, 3 liters of distilled water was added, and sulfuric acid was added until the silver halide settled. Again, 3 liters of the supernatant was removed (second water wash). The same operation as the second water washing was further repeated once (third water washing) to complete the water washing / desalting process. The emulsion after washing and desalting is adjusted to pH 6.4 and pAg 7.5, and 10 mg of sodium benzenethiosulfonate, 3 mg of sodium benzenethiosulfinate, 15 mg of sodium thiosulfate and 10 mg of chloroauric acid are added. And 1,3,3a, 7-tetraazaindene (100 mg) as a stabilizer and 100 mg of proxel (trade name, manufactured by ICI Co., Ltd.) as a preservative were added. The finally obtained emulsion contains 0.05 mol% of silver iodide, and the ratio of silver chlorobromide is 70 mol% of silver chloride and 30 mol% of silver bromide. It was a silver iodochlorobromide cubic grain emulsion having a coefficient of 9%. The volume ratio of silver to binder (gelatin) in this emulsion is 2.0.

(Preparation of photosensitive layer coating solution)
Gelatin was added to the emulsion so that the volume ratio of silver to gelatin was 1.0, and 1,3,3a, 7-tetraazaindene was 1.2 × 10 ⁻⁴ mol / mol Ag, hydroquinone 1 0.2 × 10 ⁻² mol / mol Ag, citric acid 3.0 × 10 ⁻⁴ mol / mol Ag, 2,4-dichloro-6-hydroxy-1,3,5-triazine sodium salt 0.90 g / mol Ag A small amount of a hardener was added, and the coating solution pH was adjusted to 5.6 using citric acid to prepare a photosensitive layer coating solution, which was designated as photosensitive layer coating solution 1.
(Preparation of photosensitive materials 1-32)

A 100 μm polyethylene terephthalate (PET) film was subjected to corona discharge treatment, and then a 0.1 μm thick gelatin undercoat layer (adhesive layer 56) was provided to form a transparent support 32 for a conductive sheet. On the undercoat layer of the support, the photosensitive layer coating solution 1 prepared and prepared above and a protective layer coating solution made of gelatin containing an antiseptic are applied and dried by a simultaneous coating machine, and the photosensitive material 1 is obtained. It was created. The silver coating amount of the photosensitive layer is an amount converted from the silver image thickness in Table 2. The protective layer has a thickness of 0.15 μm.
Similarly to the photosensitive layer coating solution 1, photosensitive layer coating solutions having the compositions shown in Table 2 were prepared. Since the photosensitive layer in Table 2 may have three layers, all examples are represented by a three-layer configuration for convenience, and are represented as a u layer, an m layer, and an o layer from the side close to the support. The photosensitive material 1 prepared above is an example of a photosensitive layer composed of a single coating layer composed only of the photosensitive layer coating solution 1. Photosensitive materials 2 to 9 are also examples of a photosensitive layer composed of a single coating layer in the same manner as the photosensitive material 1 although there are differences in silver image thickness, silver density, and the presence or absence of an inhibitor. Here, as in the case of the photosensitive layer coating solution 1, when the volume ratio of silver and binder (gelatin) is smaller than 2.0 of the standard formula, the volume of silver and binder (gelatin) is added by adding gelatin to the coating solution. When adjusting the ratio and changing the ratio of silver chloride and silver bromide, the coating liquids shown in Table 2 were prepared and prepared by changing the ratios of sodium chloride and potassium bromide in the above three and five solutions. .

Unlike the photosensitive materials 1 to 9, the photosensitive materials 10 to 32 are photosensitive materials in which three photosensitive layers of the u layer, the m layer, and the o layer are laminated from the side close to the support. 10 is a four-layer coating on the transparent support 32 used for the photosensitive material 1 by using a simultaneous coater. Three layers of photosensitive layers u, m, and o, and a protective layer used for the photosensitive material 1 are applied. Created by drying. Photosensitive materials 11 to 32 were prepared in the same manner as the photosensitive material 10.
In Table 2, the indications in parentheses in the “silver density of each layer” column indicate the film thickness ratio. For example, the film thickness ratio of the u layer / m layer / o layer of the photosensitive material 10 is 0.2 / 0. .6 / 0.2. The film thickness and silver amount of each of the three photosensitive layers (u layer, m layer, and o layer) can be calculated from the film thickness ratio, the silver density of each layer, and the silver image thickness of the entire photosensitive layer.
As described above, the volume ratio of silver and binder in Table 2 was converted to volume assuming that the density of developed silver was 10.5 and the density of the binder was 1.34. The density of 1.34 is a density applicable to gelatin. When using other polymer compounds, conversion according to the compound is necessary. Moreover, the addition amount of the development inhibitory compound used for each photosensitive layer was displayed as mg of the development inhibitory compound added to 1 g of silver. The structure of the development inhibiting compound used is shown after Table 2.

(Exposure and development processing)
Next, a photomask having the following pattern was brought into close contact with the photosensitive materials 1 to 33 prepared above and exposed using a high-pressure mercury lamp. The photomask has the pattern of FIG. 10 (upper electrode 11 in FIG. 9), the light transmission window is the negative pattern of FIG. 10, the line width of the unit square lattice forming the lattice is 3 μm, and the side length of the lattice Is 300 μm.
After exposure, the film is developed with the following developer, further developed with a fixer (trade name: N3X-R for CN16X: manufactured by Fuji Photo Film Co., Ltd.), rinsed with pure water, dried, and transparent. Conductive sheets 1 to 32 were obtained.

(Developer composition)
The following compounds are contained in 1 liter (L) of the developer.
Hydroquinone 0.037mol / L
N-methylaminophenol 0.016 mol / L
Sodium metaborate 0.140 mol / L
Sodium hydroxide 0.360 mol / L
Sodium bromide 0.031 mol / L
Potassium metabisulfite 0.187 mol / L

(Evaluation)
The following evaluation was performed using the single-sided electrode type transparent conductive sheets 1 to 32 created as described above. The evaluation was performed on the following scales for the suitability of production, the absolute value of the difference in reflection chromaticity between the front and back surfaces of the conductive sheet, and the conductivity, and the results are shown in Table 2.
(1) Manufacturability Manufacturability is indicated by ◯ for those with the same process load as for the production of transparent conductive sheet 1, and x for those requiring adjustment of processing temperature and time in the development process. .
(2) Samples for measurement of reflection chromaticity b ₁ ^* and b ₂ ^* are placed on a BCRA black tile (glossy plate), irradiated from 0 ° direction, and spectral reflectance of light received in 45 ° direction Measure. Preferred tile is Sakata Engineering BCRA black tiles Co., Ltd. (gloss plate), the reflection chromaticity of the black tile, L ^* is 3.6, ^{a *} is -0.9, b ^* -0.6 It is. As the reflection densitometer, Spectro Eye LT manufactured by GretagMacbeth (Gretag Macbeth) can be used.
The reflection chromaticity measurement sample is not a normal mask for pattern exposure but a conductive sheet obtained by developing a uniform exposure (solid exposure) sample. Specifically, the reflection chromaticity when the sample is measured from the electrode surface side is defined as reflection chromaticity b ₁ ^*, and the reflection chromaticity when the sample is measured from the transparent support side is defined as reflection chromaticity b ₂ ^*. The absolute value (| Δb * |) of the difference Δb ^* was calculated from the obtained reflection chromaticity b ₁ ^* and reflection chromaticity b ₂ ^* .
Evaluation x: The absolute value of the difference Δb ^* is 1.7 or more.
Evaluation (circle): The absolute value of difference (DELTA) b ^* is 1.0 or more and less than 1.7.
Evaluation A: The absolute value of the difference Δb ^* is less than 1.0.
(3) Evaluation of conductivity The resistance value of the electrode of the transparent conductive sheet was directly read and evaluated based on the resistance value of the transparent conductive sheet 1.
Evaluation x: Inferior to the resistance value of the transparent conductive sheet 1 for some reason. The surface resistance value exceeds 50Ω / □.
Evaluation (circle): It is substantially equivalent to the resistance value of the transparent conductive sheet 1. The standard of the surface resistance value is 20 to 50Ω / □.
Evaluation A: The resistance value of the transparent conductive sheet 1 is clearly lower than the resistance value. The surface resistance value is less than 20Ω / □.
The above results are summarized in Table 2 below. The chemical formula of the compound used in this example is attached.

From Table 2 above, the following can be understood.
The transparent conductive sheets 1 to 9 are transparent conductive sheets prepared by pattern exposure of a photosensitive material in which a photosensitive layer is formed from a single photosensitive layer coating solution. Each of the transparent conductive sheets 1 to 9 is manufactured, reflected chromaticity, or conductive. However, there are problems described below.
The transparent conductive sheets 1 to 5 are samples in which the volume ratio of silver and binder in the photosensitive layer is changed from 0.3 to 2.0, but the transparent conductive sheets 1 to 3 are different in the reflection chromaticity of the electrodes (| Δb * |) Is too large, and it is necessary to select a surface to be used according to the purpose of use. Since the transparent conductive sheets 4 and 5 have a high binder ratio, it is difficult to obtain a resistance value necessary for the conductive sheet.
The transparent conductive sheets 6 to 9 are samples obtained by increasing the silver bromide ratio of the silver chlorobromide emulsion, adding a development inhibitor, and increasing the coating amount with respect to the transparent conductive sheet 1 described above. In any case, it is necessary to increase the development temperature in the development process step and increase the development time as compared with the transparent conductive sheet 1, and therefore treatment such as a prescription change for suppressing fogging due to development is required.
On the other hand, the transparent conductive sheets 10 to 32 divide the photosensitive layer into a plurality of layers (three layers in the embodiment) unlike the transparent conductive sheets 1 to 9, and in a part of the divided layers, The ratio of silver bromide in the silver chlorobromide emulsion is increased, the volume ratio of silver and binder is changed, a development inhibitor is added, or these are combined. Then, by changing the composition of a part of the photosensitive layer as described above, the transparent conductive sheets 10 to 33 satisfy all of suitability for manufacture, reflection chromaticity, and conductivity. It is presumed that the production suitability problems as in the transparent conductive sheets 6 to 9 do not occur because the suppression of development acts on only a part of the photosensitive layer.

Example 2
The touch panel shown by FIG. 2 was created using the transparent conductive sheets 1-32 which have an electrode only on the single side | surface of the transparent support body created in the said Example 1. FIG. Specifically, two transparent conductive sheets 1 are used as the upper electrode 11 and the lower electrode 12 so that the electrode surface of the upper electrode 11 and the electrode surface of the lower electrode 12 face each other, and A touch panel 101 was formed by laminating through an adhesive layer so that the conduction directions were orthogonal and no conduction was made. In this touch panel, the toucher visually recognizes the chromaticity b ₂ ^* value on the support side with the upper electrode and the chromaticity b ₁ ^* value on the electrode surface side with the lower electrode. Similarly, touch panels 102 to 133 were created.

(Evaluation)
The following evaluation was performed using the touch panels 101 to 133 created as described above. The evaluation was performed on the following scales for the suitability for production, the absolute value of the difference in reflection chromaticity between the front and back surfaces of the conductive sheet, and the conductivity, and the results are shown in Table 3.
(1) Manufacturability
The production suitability of the transparent conductive sheet is the same evaluation as in Example 1, and is omitted.
(2) Difference in reflection chromaticity Measurement is performed in the same manner as in Example 1, and the evaluation scale is also the same as that in Example, and is therefore omitted.
(3) Evaluation of visibility Observe the created double-sided electrode type transparent conductive sheet touch panel in the vertical direction and oblique directions of each direction, coloring of reflected light, uneven color of reflected light, fluctuation of reflected light, contour of electrode Sensory evaluation such as was performed as follows.
Evaluation × I am interested.
△ Depending on the direction, you may be worried.
Evaluation ○ Almost no concern.
Evaluation ◎ Not concerned at all.
(4) Evaluation of conductivity The results of Example 1 are described.

Table 3 shows the following.
The touch panels 101 to 109 are touch panels using transparent conductive sheets 1 to 9 prepared by pattern exposure of a photosensitive material in which a photosensitive layer is formed from a single photosensitive layer coating solution. There is a problem described below in either the reflection chromaticity or the conductivity.
The touch panels 101 to 105 are touch panels prepared from a photosensitive material in which the volume ratio of silver and binder in the photosensitive layer is changed from 0.3 to 2.0. Δb * |) and the color unevenness visibility by the sensory test are clearly problems. Since the touch panels 4 and 5 have a high binder ratio, the conductive sheet used for the touch panel has a resistance value that is too high and is not suitable for a large screen.
Further, the touch panels 106 to 109 are conductive sheets obtained by increasing the silver bromide ratio of the silver chlorobromide emulsion, adding a development inhibitor, or increasing the coating amount with respect to the touch panel 1 described above. Although it is a touch panel using this, the solution of the manufacturing problem described in Example 1 is required.

On the other hand, unlike touch panels 101 to 109, touch panels 110 to 133 divide a photosensitive layer into a plurality of layers (three layers in the embodiment), and silver chlorobromide is partly in the divided layers. The silver bromide ratio in the emulsion is increased, the volume ratio of silver and binder is changed, a development inhibitor is added, or these are combined. And by changing the composition of a part of the photosensitive layer as described above, the touch panel using the transparent conductive sheets 10 to 32 includes samples satisfying all of the manufacturing suitability, the reflection chromaticity, and the conductivity. This will be described in detail below.
Touch panels 110 and 111 using electrodes formed by changing the silver bromide ratio of the silver halide in the u layer close to the transparent support from 30 mol% to 50 mol% and 70 mol% with respect to the touch panel 101 The measurement value of reflected chromaticity and the color unevenness visibility are greatly improved with respect to the touch panel 101. On the other hand, the touch panels 112 and 113 using the electrodes formed by changing the silver bromide ratio of the silver halide in the o layer far from the transparent support from 30 mol% to 50 mol% and 70 mol% have an improvement effect. Rather, the color unevenness tends to deteriorate. Therefore, it was found that an emulsion having a high bromide rate is effective when used in the u layer.
The touch panels 114 to 116 are samples in which the silver density (volume ratio of silver and binder) is changed. The touch panel 115 is a sample in which the silver density of the o layer is changed from 1.0 to 0.3, and has no improvement effect on the color. On the other hand, the touch panel 114 is a sample in which the silver density of the u layer is changed from 1.0 to 0.3, and shows a great improvement effect. The touch panel 116 showed an intermediate performance between 114 and 115. From the above, it was found that changing the silver density has a great influence on the color of the developed silver surface, and it is effective to lower the silver density of the u layer to improve the color.
The touch panels 117 to 119 are touch panels using a sample in which a development inhibitor is added only to the u layer, and the improvement effect on the color is greater than 108 added to all layers. The development inhibitors R-1 and 12 are less effective in improving the tint than the development inhibitor F, but are easy-to-use inhibitors when the color is slightly corrected.

The touch panels 120 to 123 are a sample in which the bromination rate of the u-layer emulsion is increased and the silver density is reduced, and a sample in which the bromination rate of the u-layer emulsion is increased and a development inhibitor is added. There is a great improvement effect on color. In particular, 123 with a high bromide ratio of the emulsion in the u layer and the addition of a development inhibitor is particularly effective in improving the color.
The touch panel 115 that does not show any effect of improving the color can be improved by lowering the silver density of the o layer and increasing the bromide rate of the u layer emulsion (125). Similarly, the tint can be further improved by lowering the silver density of the o layer and adding a development inhibitor to the u layer (126).
Compared to the touch panel 114 that is almost satisfactory in terms of color, 124 with a lower silver density in the o layer shows almost the same color result, and a development inhibitor added to the u layer (131) shows a further improvement effect. It was.

Example 3
The double-sided conductive sheet 10 in which the upper electrode and the lower electrode were formed on both sides of the transparent support 32 was created. As the emulsion used, the silver chlorobromide emulsion described in Example 1 was used. The coating solution on the front surface was in the “table” row in Table 4, and the coating solution on the back surface was “back” in Table 4. Created according to the description on the line. The concept and calculation method, such as the classification of the o / m / u layer, the volume ratio of silver and binder, and the halogen ratio of the emulsion, are the same as in Example 1. The photosensitive material 05 in which the photosensitive layer was formed on both sides of the support using the above coating solution was subjected to the same exposure and development treatment as in Example 1 to prepare double-sided conductive sheets 51-68. The exposure is different from the first embodiment in that the front and back photosensitive layers are simultaneously exposed using the double-sided exposure apparatus shown in FIG.
A high-pressure mercury lamp is used as a light source for double-sided exposure. The pattern-forming mask in FIG. 10 is used as the front-side photomask, and the pattern-forming mask in FIG. 11 is used as the back-side photomask. And exposed. The light transmission windows of the mask used were the negative patterns shown in FIGS. 10 and 11, respectively. The line width of the unit square lattice forming the lattice was 3 μm, and the side length of the lattice was 300 μm. When the photomask 110 used for forming the front surface electrode and the photomask 120 used for forming the back surface electrode are perpendicular to each other, the conduction direction of the formed electrodes is orthogonal, and the double-sided conductive sheet is seen through. The formed conductive thin wire pattern is installed so as to form a uniform pattern as shown in FIG.
Touch panels 201-218 of FIG. 3 were created using the above-described double-sided conductive sheets 51-68.
In the touch panels of Examples 2 and 3, it is necessary to align the two transparent conductive sheets when creating the touch panel, whereas the double-sided conductive sheet of this example is adjusted at the time of exposure. And the manufacturing yield of the touch panel is much higher than 3.

The touch panel prepared as described above was evaluated for reflection chromaticity, visibility, and conductivity, and the results are shown in Table 4.
(1) Measurement of reflection chromaticity b ₁ ^* and b ₂ ^* and the absolute value of the difference between them The measurement apparatus and measurement conditions are the same as in Example 1.
The reflection chromaticity measurement sample is not an ordinary mask for pattern exposure, but the front surface exposure mask 110 uses a mask with a window having a size capable of measuring reflection chromaticity. For the exposure, the entire surface was exposed without using a mask. The reflection chromaticity is measured from the front surface side, and the reflection chromaticity b ₁ ^* of the exposed portion of the front surface where the silver image is formed is defined as reflection chromaticity b ₁ ^* , and the front surface is not exposed. the reflection chromaticity was measured reflection chromaticity b ₂ ^* and then, the obtained reflection chromaticity b ₁ ^*, from the reflection chromaticity b ₂ ^*, and calculates the absolute value of the difference △ b ^*.
X Evaluation: The absolute value of the difference Δb ^* is 1.7 or more.
○ Evaluation: The absolute value of the difference Δb ^* is 1.0 or more and less than 1.7.
Evaluation: The absolute value of the difference Δb ^* is less than 1.0.
(2) Evaluation of visibility Observe the touch panel using the created double-sided electrode type transparent conductive sheet in the vertical direction and oblique directions of each direction, coloring of reflected light, uneven color of reflected light, fluctuation of reflected light, Sensory evaluations such as electrode contours were performed as follows.
Evaluation × I am interested.
Evaluation △ Depending on the direction, it is worrisome.
Evaluation ○ Almost no concern.
Evaluation ◎ Not concerned at all.
(3) Evaluation of conductivity The resistance value of the electrode of the transparent conductive sheet was directly read and evaluated based on the resistance value of the transparent conductive sheet 51.
Evaluation x: Inferior for some reason than the resistance value of the transparent conductive sheet 51. The surface resistance value exceeds 50Ω / □.
Evaluation (circle): It is substantially equivalent to the resistance value of the transparent conductive sheet 51. The standard of the surface resistance value is 20 to 50Ω / □.
Evaluation A: The resistance value of the transparent conductive sheet 51 is clearly lower than the resistance value. The surface resistance value is less than 20Ω / □.

From Table 4 above, the following can be understood.
The comparative touch panel 201 has a reflection chromaticity difference Δb ^* of 2.3, which is 1.7 or more, and is a level at which color unevenness is a concern even in a sensory test. On the other hand, the touch panels 202 to 218 as examples of the present invention, except for 205, show good results in all of the absolute value of the difference in reflection chromaticity Δb ^* , the visibility by the sensory test, and the conductivity. ing. Hereinafter, features of the present invention will be described.
Touch panels 202 and 203 are samples in which the silver bromide content of the u layer of both electrodes is changed from 30 mol% to 50 mol% and 70 mol%, and the absolute value of the difference Δb ^{* in} the reflection chromaticity, The visibility by the sensory test is greatly improved from the touch panel 201.
The touch panels 204 to 206 are samples in which the silver density (volume ratio of silver and binder) is changed. The 204 in which the silver density of the u layer on both sides was changed to 1.0 to 0.3 was satisfactory in both the absolute value of the difference in reflection chromaticity Δb ^{* and} the visibility by the sensory test. 206 in which the silver density of the u layer and the o layer was changed to 1.0 to 0.3 was not at a level where the measured value of the difference in reflection chromaticity was satisfactory, but at a sufficient level in the sensory test. Moreover, 205 which changed the silver density of o layer of both surfaces to 1.0-0.3 does not improve 201 of a comparative example at all. From these, it was found that the layer effective when the silver density is lowered is the o layer which is a layer closer to the transparent support.
The touch panels 207 and 208 are samples in which the silver bromide content of the u layer is increased and the silver density is reduced, and both of them satisfy both the absolute value of the difference in reflection chromaticity Δb ^{* and} the visibility by the sensory test. Is on the level.
The touch panels 209 to 211 are samples obtained by adding a development inhibitor to the u layer of 203, 204, and 208, and the touch panel 212 is a sample obtained by adding 50 mol% of silver bromide and adding a development inhibitor to the u layer of 206. Yes, the same performance as the above 207 and 208 is obtained.
The touch panels 209, 213, and 214 are samples that compare the effects of the development inhibitors used in the examples. The development inhibitors R-1 and 12 are less effective in improving the tint than the development inhibitor F, but are easy-to-use inhibitors when the color is slightly corrected.

In the above, the example of the touch panel using the transparent conductive sheet which provided the electrode of the same design on the front surface and the back surface of the double-sided electrode has been described. Hereinafter, touch panels 215 to 218 using transparent electrodes whose front and back electrode designs are not identical will be described.
In each of the touch panels 215 to 217, one side of the conductive sheet 51 as a comparative example was used as the front surface electrode, and a conductive sheet that can reduce the difference Δb ^* in reflection chromaticity was selected as the back surface electrode. As a result, the absolute value of the difference Δb ^* in reflection chromaticity, the visibility by the sensory test, and the conductivity were all satisfactory. The touch panel 218 is a sample in which the silver bromide content of the o layer on the front surface is 70 mol%, and the chromaticity of the front surface is slightly bluish, which is effective for slight color adjustment. I understood it.

01 Touch panel 02 Touch surface 03 Touch surface cover 05 Photosensitive material 10 for producing a transparent conductive sheet (also referred to as an electrode sheet) Transparent conductive sheet (also referred to as an electrode sheet, also referred to as a double-sided conductive sheet)
11 Upper conductive sheet (also called electrode sheet, also called front electrode)
12 Lower conductive sheet (also called electrode sheet, also called back surface electrode)
14A, 14B A plurality of conductive lattice portions 16A, 16B for sensing capacitances Conductive connecting portions 18A, 18B that connect the lattices to the lattices Lead wires 19 that connect electrodes (also referred to as conductive patterns) and external control portions 19 Dummy thin wires 21 Conductive fine wire 22 constituting upper electrode (also referred to as conductive pattern) Conductive fine wire 30 constituting lower electrode (also referred to as conductive pattern) Transparent support 31 for touch surface For conductive sheet (electrode sheet) also serving as touch surface Transparent support 32 Transparent support 33 for conductive sheet (electrode sheet) Transparent support 34 Glass plate 41, 42 Adhesive layer 50 also serving as an insulating layer Upper photosensitive material layer (front surface photosensitive material layer)
51 Upper photosensitive layer (front surface photosensitive layer)
52 Upper first photosensitive layer (upper u layer)
53 Upper second photosensitive layer (upper m layer)
54 Upper third photosensitive layer (upper o layer)
55 Upper protective layer 56 Upper undercoat layer 57 Upper antihalation layer 60 Lower photosensitive material layer (back side photosensitive material layer)
61 Lower photosensitive layer (back side photosensitive layer)
62 Lower first photosensitive layer (lower u layer)
63 Lower second photosensitive layer (lower m layer)
64 Lower third photosensitive layer (lower o layer)
65 Lower protective layer 66 Lower undercoat layer 67 Lower antihalation layers 100a and 100b Light sources a and b for exposure
101a, 101b Exposure lenses a and b
102, 102a, 102b Representing parallel light for exposure 110 Photomask used for forming upper electrode (also referred to as conductive pattern, front surface electrode) 120 For forming lower electrode (also referred to as conductive pattern, back surface electrode) Photomasks 111 and 121 used for the light transmission portions 112 and 122 of the photomask Light shielding portions 131 and 141 of the photomask Exposed portions (portions where latent images are formed) in the photosensitive layer
132, 142 Parts of the photosensitive layer that were not exposed (parts where no latent image was formed)
151 (21) Silver fine wire of the upper electrode formed after development processing (conductive thin wire constituting the upper electrode)
161 (22) Silver thin wire of the lower electrode formed after development processing (conductive thin wire constituting the lower electrode)
152, 162 Transparent layer d1 from which unexposed silver halide emulsion and the like have been removed by development processing Region where conductive fine lines of upper electrode are continuously arranged (place visible as b ₁ ^* )
d2 Area where conductive thin wires of the lower electrode are continuously arranged (place visually recognized as b ₂ ^* )
ZZ The portion of the conductive sheet (electrode sheet) roughly corresponding to the cross section of the touch panel of FIGS.

Claims (19)

  This is a photosensitive material for producing a transparent conductive sheet, wherein a photosensitive material having a photosensitive layer containing a silver halide emulsion formed on a transparent support is subjected to pattern exposure and development processing to produce a transparent conductive sheet comprising conductive thin wires. The photosensitive layer comprises at least one of a plurality of photosensitive layers containing emulsions having different halogen compositions, a plurality of photosensitive layers having different silver densities, or a plurality of photosensitive layers having different amounts of addition of a development inhibitor. A photosensitive material for producing a transparent conductive sheet.   The photosensitive material is a photosensitive material for producing a conductive sheet in which a photosensitive layer containing a silver halide emulsion is formed on both sides of a transparent support, and at least one of the photosensitive layers has a halogen composition. 2. The transparent according to claim 1, comprising at least one of a plurality of photosensitive layers containing different emulsions, a plurality of photosensitive layers having different silver densities, and a plurality of photosensitive layers having different addition amounts of development inhibitors. Photosensitive material for producing conductive sheets.   The silver halide emulsion of the photosensitive layer is a silver chlorobromide emulsion, and the silver bromide content is most from the photosensitive layer in the portion close to the transparent support surface or from the support as compared to the central portion of the photosensitive layer. The photosensitive material for producing a transparent conductive sheet according to claim 1 or 2, wherein the silver bromide content of the photosensitive layer in the far part is higher by 5 mol% or more.   The silver chlorobromide emulsion in the central part of the photosensitive layer has a silver bromide content of less than 40 mol%, and the chlorobromide of the photosensitive layer in the part closest to the transparent support surface or the photosensitive layer farthest from the support. 4. The photosensitive material for producing a transparent conductive sheet according to claim 3, wherein the silver bromide content of the silver emulsion is 40 mol% or more.   The silver layer of the photosensitive layer containing the silver chlorobromide emulsion in the central part of the photosensitive layer and the silver layer of the photosensitive layer in the part farthest from the support with respect to the volume ratio of silver and binder in the photosensitive layer The photosensitive material for producing a transparent conductive sheet according to any one of claims 1 to 4, wherein the volume ratio of the binder is small.   The volume ratio of silver to binder in the photosensitive layer containing the silver chlorobromide emulsion at the center of the photosensitive layer is 0.7 or more, and the photosensitive layer in the part closest to the transparent support surface or the part farthest from the support is exposed. 6. The photosensitive material for producing a transparent conductive sheet according to claim 5, wherein the volume ratio of silver and binder in the layer is from 0.05 to 0.5.   The photosensitive layer having a small volume ratio of silver and binder contains a development inhibitor, and the other photosensitive layer having a small volume ratio of silver and binder contains no development inhibitor. 2. A photosensitive material for producing a transparent conductive sheet according to any one of the above items.   The photosensitive material for producing a transparent conductive sheet according to claim 7, wherein the development inhibitor is a mercapto compound.   The photosensitive material for producing a transparent conductive sheet according to claim 1, wherein the development inhibitor is a compound that releases the development inhibitor by an oxidation-reduction reaction.   A transparent conductive pattern (also referred to as an electrode) composed of developed thin conductive silver wires by pattern exposure to the photosensitive material for producing a conductive sheet according to any one of claims 1 to 3 and subsequent development. ) Is formed on one side of a transparent support.   Two transparent conductive sheets according to claim 10 are used, and the conductive thin wires of each transparent conductive sheet are on the toucher side, and are laminated so that the conductive directions of the conductive thin wires of each conductive pattern are orthogonal to each other. A capacitive touch panel characterized by the above.   Two transparent conductive sheets according to claim 10 were used, and the transparent support of each transparent conductive sheet was on the toucher side, and the conductive patterns were laminated so that the conductive directions of the conductive thin wires were orthogonal to each other. A capacitive touch panel characterized by the above.   The two transparent conductive sheets according to claim 10 are used, and the conductive thin wires of the respective transparent conductive sheets face each other through an insulator other than the transparent support of the transparent conductive sheet, and the conductive thin wires of the respective conductive patterns. A capacitive touch panel, which is laminated so that the conduction directions of the electrodes are orthogonal to each other. The touch panel according to any one of claims 11 to 13, wherein the reflection chromaticity b ^* value of the conductive pattern measured from the toucher side is the conductive pattern (upper part) of the two conductive patterns closer to the toucher. When the reflection chromaticity b ₁ ^* of the conductive pattern) and the reflection chromaticity b ₂ ^* of the conductive pattern (lower conductive pattern) on the side far from the toucher are given, the reflection chromaticity b ₁ ^* and the reflection chromaticity b ₂ ^* The absolute value of the difference between the touch panel is less than 1.7 (| Δb ^* | = | b ₁ ^* −b ₂ ^* | <1.7).   The photosensitive material for producing a transparent conductive sheet according to claim 1, wherein the photosensitive material has an antihalation layer between the transparent support and the photosensitive layer.   The transparent conductive pattern which consists of an electroconductive fine wire of image development silver is carried out by giving pattern exposure to both surfaces of the photosensitive material for conductive sheet manufacture of any one of Claims 2-9, and carrying out development processing then, of a transparent support body. A double-sided conductive pattern type transparent conductive sheet characterized by being formed on both sides.   17. The double-sided conductive pattern type transparent conductive sheet according to claim 16, wherein the conduction direction of the conductive fine wire of the transparent conductive sheet on one side and the conduction direction of the conductive fine line of the transparent conductive sheet on the other side are mutually A double-sided conductive pattern type transparent conductive sheet that is exposed so as to be orthogonally arranged.   18. A capacitive touch panel using the double-sided conductive pattern type transparent conductive sheet according to claim 17. 19. The capacitive touch panel using the double-sided conductive pattern type transparent conductive sheet according to claim 18, wherein the reflection chromaticity b ^* value of the conductive pattern measured from the toucher side is close to the toucher of the double-sided conductive pattern. a reflection chromaticity b ₁ ^* side of the conductive pattern (front surface conductive pattern), when the reflection chromaticity b ₂ ^* farther conductive pattern on the touch's (back surface conductive pattern), the reflection chromaticity b The absolute value of the difference between ₁ ^* and the reflected chromaticity b ₂ ^* is less than 1.7 (| Δb ^* | = | b ₁ ^* −b ₂ ^* | <1.7). .

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