JP5827817B2 - Conductive sheet, method for manufacturing conductive sheet, and capacitive touch panel using conductive sheet - Google Patents

Description

  The present invention relates to a conductive sheet having a conductive fine wire having a high-definition pattern formed on a support, a conductive sheet having a conductive fine wire having a high-definition pattern formed on a support using silver halide, It relates to a manufacturing method. Furthermore, the present invention can be used as, for example, various electrodes (for example, electrodes for touch panels, electrodes for inorganic EL elements, electrodes for organic EL elements, or electrodes for solar cells), heat generating sheets, and printed wiring boards. Regarding the sheet.

  Conventionally, a method for forming a low-resistance conductive fine wire from a silver image obtained by development of a silver halide photographic light-sensitive material has been studied in the field of electromagnetic shielding films and printed wiring. In this method, since various patterns can be formed by exposure through a mask and subsequent development processing, the manufacturing process is stable. For example, Patent Document 1 can be cited as a developing method, 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.

  Silver having high conductivity has a problem that ion migration is likely to occur. Ion migration is a kind of electrode action, and is a phenomenon in which when an electrolyte is present between electrodes to which voltage is applied, the metal of the anode elutes, moves to the cathode, and precipitates. If ion migration occurs between wiring metals, elution and migration occur, and the deposited metal is short-circuited, the circuit function cannot be performed.

  As a method for suppressing ion migration, a method of cross-linking a resin component after forming an electrode pattern (Patent Document 2) has been proposed.

  However, the technique described in Patent Document 2 has a problem in terms of productivity and cost because a step of applying a crosslinking agent after development is required and the number of steps increases. In addition, the migration resistance is insufficient only by causing the crosslinking agent to act, which is a problem.

JP 2007-129205 A JP 2010-205927 A

  The present invention has been made in consideration of the above problems, and an object thereof is to provide a conductive sheet having excellent migration resistance. Furthermore, this invention aims at provision of the method of manufacturing the conductive sheet which is excellent in the said migration tolerance, without increasing a process.

上記式中、
Ｒ^１はメチル基又はハロゲン原子を表す。ｐは０〜２の整数を表す。
Ｒ^２はメチル基又はエチル基を表す。
Ｒ^３は水素原子又はメチル基を表す。Ｌは２価の連結基を表す。ｑは０又は１を表す。
Ｒ^４は炭素原子数５〜８０のアルキル基、アルケニル基、又はアルキニル基を表す。
Ｒ^５は水素原子、メチル基、エチル基、ハロゲン原子、又は−ＣＨ_２ＣＯＯＲ^６を表す。
Ｒ^６は水素原子又は炭素原子数１〜８０のアルキル基を表す。
＜１２＞
前記ポリマーラテックスが、更に分散剤を含有し、該ポリマーラテックスにおける該分散剤とポリマーとの質量比（分散剤／ポリマー）が０．０５以下である、＜１＞〜＜４＞、＜８＞、＜１１＞のいずれか１項に記載の導電シート。
＜１３＞
前記バインダー部に更に銀難溶剤を含有する、又は前記バインダー部が銀難溶剤への浸漬処理を施されたものである、＜１＞〜＜４＞、＜８＞、＜１１＞、＜１２＞のいずれか１項に記載の導電シート。
＜１４＞
前記導電シートを１００％延伸したときの電気抵抗値をＲｂ、延伸する前の電気抵抗値（初期値）をＲ０とした場合、Ｒｂ≦（２×Ｒ０）を満足する、＜１＞〜＜４＞、＜８＞、＜１１＞〜＜１３＞のいずれか１項に記載の導電シート。
＜１５＞
＜１＞〜＜４＞、＜８＞、＜１１＞〜＜１４＞のいずれか１項に記載の導電シートを用いた静電容量方式のタッチパネル。
本発明は、上記＜１＞〜＜１５＞に関するものであるが、その他の事項（たとえば下記［１］〜［２１］に記載した事項など）についても参考のために記載した。
［１］
支持体上に、金属銀を含有する導電性細線からなる導電層と、前記導電性細線間に存在するバインダー部とを有する導電シートであって、
前記バインダー部の含水率が１０％以下であり、前記導電層の表面抵抗が１０００オーム／ｓｑ．以下である、導電シート。
［２］
前記バインダー部が、ポリマーラテックスと水溶性高分子とを含有し、前記ポリマーラテックスと前記水溶性高分子との質量比（ポリマーラテックス／水溶性高分子）が１以上である、上記［１］に記載の導電シート。
［３］
前記ポリマーラテックスと前記水溶性高分子との質量比（ポリマーラテックス／水溶性高分子）が１．５〜３．５である、上記［２］に記載の導電シート。
［４］
前記金属銀と前記ポリマーラテックスとの質量比（金属銀／ポリマーラテックス）が１〜１０である、上記［２］又は［３］に記載の導電シート。
［５］
支持体上に、ハロゲン化銀と、ポリマーラテックスを含むバインダーとを含有する感光性層を形成し、該感光性層を露光、現像処理した後に更に加熱処理することにより形成された金属銀を含有する導電性細線からなる導電層と、該導電性細線間に存在するバインダー部とを有する導電シートであって、前記バインダー部の含水率が１０％以下であり、前記導電層の表面抵抗が１０００オーム／ｓｑ．以下である、導電シート。
［６］
前記加熱処理における温度が４０℃以上である、上記［５］に記載の導電シート。
［７］
前記バインダーが水溶性高分子であり、前記ポリマーラテックスと前記水溶性高分子との質量比（ポリマーラテックス／水溶性高分子）が１以上である、上記［５］又は［６］に記載の導電シート。
［８］
前記ポリマーラテックスと前記水溶性高分子との質量比（ポリマーラテックス／水溶性高分子）が１．５〜３．５である、上記［７］に記載の導電シート。
［９］
前記金属銀と前記ポリマーラテックスとの質量比（金属銀／ポリマーラテックス）が１〜１０である、上記［５］〜［８］のいずれか１項に記載の導電シート。
［１０］
前記水溶性高分子がゼラチンである、上記［２］〜［４］及び［７］〜［９］のいずれか１項に記載の導電シート。
［１１］
前記加熱処理が４０℃以上かつ相対湿度５％以上で行われる、上記［５］〜［１０］のいずれか１項に記載の導電シート。
［１２］
前記金属銀と前記ポリマーラテックスの質量比（金属銀／ポリマーラテックス）が２．３〜７．５である、上記［２］〜［１１］のいずれか１項に記載の導電シート。
［１３］
前記ポリマーラテックスにおけるポリマーが、下記一般式（１）で表される共重合体である、上記［２］〜［１２］のいずれか１項に記載の導電シート。
一般式（１）： −（Ａ）ｘ−（Ｂ）ｙ−（Ｃ）ｚ−（Ｄ）ｗ−
一般式（１）中、Ａ、Ｂ、Ｃ、及びＤはそれぞれ下記モノマー単位を表す。ｘ、ｙ、ｚ、及びｗは各モノマー単位のモル比率を表し、ｘは３〜６０（モル％）、ｙは３０〜９６（モル％）、ｚは０．５〜２５（モル％）、ｗは０．５〜４０（モル％）を表す。 <1>
On a support, a conductive sheet comprising a conductive layer composed of conductive thin wires containing metallic silver, and a binder part existing between the conductive thin wires,
The water content of the binder part is 10% or less, and the surface resistance of the conductive layer is 1000 ohm / sq. And
The binder part contains a polymer latex and a water-soluble polymer,
The electrically conductive sheet whose mass ratio (metal silver / polymer latex) of the said metal silver and the said polymer latex is 2.3 or more.
However, the water content is the equilibrium water content after aging for 20 days at 60 ° C. and 90% RH, and is calculated by the weight method as follows.
Moisture content (%) of binder part = (W ₂ −W ₁ ) / W ₁ × 100
W ₁ is the mass of the binder part after aging at 120 ° C. for 4 hours (absolutely dried state), and W ₂ is the mass of the binder part after aging for 20 days at 60 ° C. and 90% RH.
When it has a protective layer on a conductive layer, a binder part also contains a protective layer.
<2>
The conductive sheet according to <1>, wherein a mass ratio of the polymer latex to the water-soluble polymer (polymer latex / water-soluble polymer) is 1 or more.
<3>
The conductive sheet according to <2>, wherein a mass ratio of the polymer latex to the water-soluble polymer (polymer latex / water-soluble polymer) is 1.5 to 3.5.
<4>
The conductive sheet according to any one of <1> to <3>, wherein a mass ratio of the metallic silver to the polymer latex (metal silver / polymer latex) is 2.3 to 7.5.
<5>
On the support, a surface resistance of 1000 ohm / sq. A conductive layer which is the following, and a binder part having a water content of 10% or less present between the conductive thin wires, and the mass ratio of the metallic silver to the polymer latex (metal silver / polymer latex) is 2 A method for producing a conductive sheet that is 3 or more,
On a support, and the silver halide to form a photosensitive layer containing a binder comprising a polymer latex, exposing the photosensitive layer, you further heat treatment after development processing, conductive sheet manufacturing method of.
However, the water content is the equilibrium water content after aging for 20 days at 60 ° C. and 90% RH, and is calculated by the weight method as follows.
Moisture content (%) of binder part = (W ₂ −W ₁ ) / W ₁ × 100
W ₁ is the mass of the binder part after aging at 120 ° C. for 4 hours (absolutely dried state), and W ₂ is the mass of the binder part after aging for 20 days at 60 ° C. and 90% RH.
When it has a protective layer on a conductive layer, a binder part also contains a protective layer.
<6>
The manufacturing method of the conductive sheet as described in <5> whose temperature in the said heat processing is 40 degreeC or more.
<7>
The conductive sheet according to <5> or <6>, wherein the binder is a water-soluble polymer, and a mass ratio of the polymer latex to the water-soluble polymer (polymer latex / water-soluble polymer) is 1 or more. Manufacturing method .
<8>
The conductive sheet according to any one of <1> to <4>, wherein the water-soluble polymer is gelatin.
<9>
The method for producing a conductive sheet according to any one of <5> to < 7 >, wherein the heat treatment is performed at 40 ° C. or higher and a relative humidity of 5% or higher.
<10>
<5>- <7> of the conductive sheet of any one of <9> whose mass ratio (metal silver / polymer latex) of the said metal silver and the said polymer latex is 2.3-7.5 . Manufacturing method .
<11>
The conductive sheet according to any one of <1> to <4> and <8> , wherein the polymer in the polymer latex is a copolymer represented by the following general formula (1).
General formula (1):-(A) x- (B) y- (C) z- (D) w-
In general formula (1), A, B, C, and D represent the following monomer units, respectively. x, y, z, and w represent the molar ratio of each monomer unit, x is 3 to 60 (mol%), y is 30 to 96 (mol%), z is 0.5 to 25 (mol%), w represents 0.5 to 40 (mol%).

In the above formula,
R ¹ represents a methyl group or a halogen atom. p represents an integer of 0 to 2.
R ² represents a methyl group or an ethyl group.
R ³ represents a hydrogen atom or a methyl group. L represents a divalent linking group. q represents 0 or 1;
R ⁴ represents an alkyl group having 5 to 80 carbon atoms, an alkenyl group, or an alkynyl group.
R ⁵ represents a hydrogen atom, a methyl group, an ethyl group, a halogen atom, or —CH ₂ COOR ⁶ .
R ⁶ represents a hydrogen atom or an alkyl group having 1 to 80 carbon atoms.
<12>
<1> to <4>, <8> , wherein the polymer latex further contains a dispersant, and the mass ratio of the dispersant to the polymer in the polymer latex (dispersant / polymer) is 0.05 or less. <11> Any one of the conductive sheets of <11> .
<13>
<1> to <4>, <8>, <11>, <12, wherein the binder part further contains a silver difficult solvent, or the binder part is subjected to a dipping treatment in a silver difficult solvent. > The conductive sheet according to any one of the above.
<14>
When the electrical resistance value when the conductive sheet is stretched 100% is Rb, and the electrical resistance value (initial value) before stretching is R0, Rb ≦ (2 × R0) is satisfied, <1> to <4 >, <8>, The conductive sheet according to any one of <11> to <13> .
<15>
<1>- <4>, <8>, <11>-<14> The capacitive touch panel using the electrically conductive sheet of any one of <14> .
The present invention relates to the above <1> to <1 5 >, but other matters (for example, the matters described in [1] to [21] below) are also described for reference.
[1]
On a support, a conductive sheet comprising a conductive layer composed of conductive thin wires containing metallic silver, and a binder part existing between the conductive thin wires,
The water content of the binder part is 10% or less, and the surface resistance of the conductive layer is 1000 ohm / sq. The conductive sheet which is the following.
[2]
In the above [1], the binder part contains a polymer latex and a water-soluble polymer, and a mass ratio of the polymer latex to the water-soluble polymer (polymer latex / water-soluble polymer) is 1 or more. The electroconductive sheet of description.
[3]
The conductive sheet according to [2] above, wherein a mass ratio of the polymer latex to the water-soluble polymer (polymer latex / water-soluble polymer) is 1.5 to 3.5.
[4]
The conductive sheet according to [2] or [3] above, wherein a mass ratio of the metallic silver to the polymer latex (metal silver / polymer latex) is 1 to 10.
[5]
Forms a photosensitive layer containing a silver halide and a binder containing a polymer latex on a support, and contains the metallic silver formed by subjecting the photosensitive layer to exposure and development and further heat treatment. A conductive sheet having a conductive layer made of conductive thin wires and a binder portion existing between the conductive thin wires, the moisture content of the binder portion is 10% or less, and the surface resistance of the conductive layer is 1000 Ohm / sq. The conductive sheet which is the following.
[6]
The conductive sheet according to [5], wherein the temperature in the heat treatment is 40 ° C. or higher.
[7]
The conductive material according to [5] or [6], wherein the binder is a water-soluble polymer, and a mass ratio of the polymer latex to the water-soluble polymer (polymer latex / water-soluble polymer) is 1 or more. Sheet.
[8]
The conductive sheet according to [7], wherein a mass ratio of the polymer latex to the water-soluble polymer (polymer latex / water-soluble polymer) is 1.5 to 3.5.
[9]
The conductive sheet according to any one of [5] to [8], wherein a mass ratio of the metallic silver to the polymer latex (metal silver / polymer latex) is 1 to 10.
[10]
The conductive sheet according to any one of [2] to [4] and [7] to [9], wherein the water-soluble polymer is gelatin.
[11]
The conductive sheet according to any one of [5] to [10], wherein the heat treatment is performed at 40 ° C. or higher and a relative humidity of 5% or higher.
[12]
The conductive sheet according to any one of [2] to [11] above, wherein a mass ratio of the metallic silver to the polymer latex (metal silver / polymer latex) is 2.3 to 7.5.
[13]
The conductive sheet according to any one of [2] to [12], wherein the polymer in the polymer latex is a copolymer represented by the following general formula (1).
General formula (1):-(A) x- (B) y- (C) z- (D) w-
In general formula (1), A, B, C, and D represent the following monomer units, respectively. x, y, z, and w represent the molar ratio of each monomer unit, x is 3 to 60 (mol%), y is 30 to 96 (mol%), z is 0.5 to 25 (mol%), w represents 0.5 to 40 (mol%).

In the above formula,
R ¹ represents a methyl group or a halogen atom. p represents an integer of 0 to 2.
R ² represents a methyl group or an ethyl group.
R ³ represents a hydrogen atom or a methyl group. L represents a divalent linking group. q represents 0 or 1;
R ⁴ represents an alkyl group having 5 to 80 carbon atoms, an alkenyl group, or an alkynyl group.
R ⁵ represents a hydrogen atom, a methyl group, an ethyl group, a halogen atom, or —CH ₂ COOR ⁶ .
R ⁶ represents a hydrogen atom or an alkyl group having 1 to 80 carbon atoms.
[14]
Any of the above [2] to [13], wherein the polymer latex further contains a dispersant, and a mass ratio (dispersant / polymer) of the dispersant to the polymer in the polymer latex is 0.05 or less. The conductive sheet according to Item 1.
[15]
The conductive sheet according to any one of [1] to [14], wherein the binder part further contains a silver difficult solvent, or the binder part is subjected to a dipping treatment in a silver difficult solvent. .
[16]
A non-photosensitive layer containing a physical development nucleus and a polymer latex is formed on a support, a peelable photosensitive layer containing silver halide is formed on the non-photosensitive layer, and the photosensitive layer And conducting a diffusion transfer development process to transfer the silver halide in the unexposed portion of the photosensitive layer to the physical development nucleus of the non-photosensitive layer, thereby forming a conductive layer composed of conductive fine wires containing metallic silver. Forming,
A conductive sheet in which a binder part is formed between the conductive fine wires by removing the photosensitive layer and further heat-treating the non-photosensitive layer on which the conductive layer is formed, and the moisture content of the binder part Is 10% or less, and the surface resistance of the conductive layer is 1000 ohm / sq. The conductive sheet which is the following.
[17]
On the support, a surface resistance of 1000 ohm / sq. It is a method for producing a conductive sheet having a conductive layer which is the following, and a binder part having a water content of 10% or less present between the conductive thin wires,
Forming a photosensitive layer containing a silver halide and a binder containing a polymer latex on a support;
A step of forming a conductive layer made of a conductive thin wire containing metallic silver by developing after exposing the photosensitive layer;
A method for producing a conductive sheet, comprising a step of forming a film of the polymer latex by heat treatment and forming a binder portion between the conductive thin wires after the development treatment.
[18]
On the support, a surface resistance of 1000 ohm / sq. It is a method for producing a conductive sheet having a conductive layer which is the following, and a binder part having a water content of 10% or less present between the conductive thin wires,
Forming a photosensitive layer containing a silver halide, a physical development nucleus and a binder containing a polymer latex on a support;
A step of forming a conductive layer made of a conductive thin wire containing metallic silver by developing after exposing the photosensitive layer;
A method for producing a conductive sheet, comprising a step of forming a film of the polymer latex by heat treatment and forming a binder portion between the conductive thin wires after the development treatment.
[19]
On the support, a surface resistance of 1000 ohm / sq. It is a method for producing a conductive sheet having a conductive layer which is the following, and a binder part having a water content of 10% or less present between the conductive thin wires,
Forming a non-photosensitive layer containing a physical development nucleus and a polymer latex on a support;
Forming a photosensitive layer containing silver halide on the non-photosensitive layer;
After the photosensitive layer is exposed, it is composed of a conductive thin wire containing metallic silver by transferring silver halide in an unexposed portion of the photosensitive layer to a physical development nucleus of the non-photosensitive layer by diffusion transfer development processing. Forming a conductive layer;
Removing the photosensitive layer;
A method for producing a conductive sheet, comprising: forming a binder portion between the conductive thin wires by forming the polymer latex in a non-photosensitive layer in which the conductive layer is formed by heat treatment after the development treatment.
[20]
When the electrical resistance value when the conductive sheet is stretched 100% is Rb, and the electrical resistance value before stretching (initial value) is R0, Rb ≦ (2 × R0) is satisfied, [1] to [ [16] The conductive sheet according to any one of [16].
[21]
A capacitive touch panel using the conductive sheet according to any one of [1] to [16] and [20].

ADVANTAGE OF THE INVENTION According to this invention, the electroconductive sheet by which the migration which generate | occur | produces by the movement of a metal ion between electroconductive fine wires was suppressed can be provided. Moreover, according to this invention, the method of manufacturing the electroconductive sheet excellent in this migration tolerance with sufficient productivity can be provided.
Since the conductive sheet of the present invention is excellent in flexibility (formability, etc.), it can be applied to various electrodes (for example, electrodes for touch panels, electrodes for inorganic EL elements, electrodes for organic EL elements, or electrodes for solar cells), As a conductive patterning material, it can be widely applied to printed wiring boards and the like, and can also be applied to heat generating sheets.

It is a cross-sectional schematic diagram which shows one example of the electrically conductive sheet of this invention. It is a conceptual diagram of the conductive layer formation process using a silver halide emulsion. It is a cross-sectional schematic diagram which shows one example of the photosensitive material used in order to manufacture the electrically conductive sheet of this invention. It is a cross-sectional schematic diagram of the touch panel model which formed the electrode (conductive layer) on both surfaces of the support body. It is a cross-sectional schematic diagram of 1 aspect of the lamination | stacking system of an upper conductive sheet and a lower conductive sheet. It is a cross-sectional schematic diagram of 1 aspect of the lamination | stacking system of an upper conductive sheet and a lower conductive sheet. It is a cross-sectional schematic diagram of 1 aspect of the lamination | stacking system of an upper conductive sheet and a lower conductive sheet. It is a schematic diagram which shows the comb-shaped pattern electrode used for a migration test.

  In the present specification, “to” is used as a meaning including numerical values described before and after the lower limit value and the upper limit value.

The conductive sheet of the present invention is a conductive sheet having, on a support, a conductive layer composed of conductive thin wires containing metallic silver, and a binder portion existing between the conductive thin wires, the water content of the binder portion Rate is 10% or less, and the surface resistance of the conductive layer is 1000 ohm / sq. It is characterized by the following.
Further, the present invention comprises a conductive thin wire containing metallic silver formed by exposing and developing a photosensitive layer containing silver halide and a polymer latex on a support and further heat-treating it. A conductive sheet having a conductive layer and a binder part, wherein the binder part exists between the conductive thin wires, the moisture content of the binder part is 10% or less, and the surface resistance of the conductive layer is 1000 ohm / sq. The following also relates to the conductive sheet.
Furthermore, the present invention forms a non-photosensitive layer containing a physical development nucleus and a polymer latex on a support, and forms a peelable photosensitive layer containing silver halide on the non-photosensitive layer. Then, the photosensitive layer is exposed and subjected to diffusion transfer development to transfer the silver halide in the unexposed portion of the photosensitive layer to the physical development nucleus of the non-photosensitive layer, thereby containing a conductive silver. A conductive sheet in which a conductive layer composed of fine wires is formed, the photosensitive layer is removed, and the non-photosensitive layer on which the conductive layer is formed is further heat-treated to form a binder portion between the conductive thin wires. The water content of the binder part is 10% or less, and the surface resistance of the conductive layer is 1000 ohm / sq. The following also relates to the conductive sheet.
The present invention also relates to a method for producing the conductive sheet.

(Moisture content of binder part)
In the conductive sheet of the present invention, the moisture content of the binder portion existing between the conductive thin wires is 10% or less. Thereby, it is considered that the conductive sheet of the present invention can exhibit excellent migration resistance. In the present invention, the water content of the binder part is preferably 3.0% to 6.5%, more preferably 4.0% to 6.5%, and even more preferably 4.6% to 5.2%.
The water content of the binder part in the present invention is an equilibrium water content after aging for 20 days at 60 ° C. and 90% RH, and is calculated by the weight method as follows.
Moisture content (%) of binder part = (W ₂ −W ₁ ) / W ₁ × 100
W ₁ is the mass of the binder part after aging at 120 ° C. for 4 hours (absolutely dried state), and W ₂ is the mass of the binder part after aging for 20 days at 60 ° C. and 90% RH.

FIG. 1 is a schematic cross-sectional view showing an embodiment of the conductive sheet of the present invention, which is present on a support 32 between a conductive layer 101 made of a conductive fine wire containing metallic silver and the conductive thin wire. A conductive sheet 10 having a binder portion 102 is shown. The water content of the binder part is 10% or less, and the surface resistance of the conductive layer is 1000 ohm / sq. It is as follows.
Such a conductive sheet of the present invention is prepared, for example, by forming a photosensitive material having a photosensitive layer containing silver halide on a support, and exposing and developing the photosensitive material, followed by heat treatment. Preferably, it is prepared by the manufacturing method of the following three aspects.
[1] A step of forming a photosensitive layer containing a silver halide and a binder containing a polymer latex on a support, a conductive material containing metallic silver by exposing the photosensitive layer and developing it. A method for producing a conductive sheet, comprising: a step of forming a conductive layer comprising fine wires; and a step of forming a film of the polymer latex by heat treatment after the development processing to form a binder portion between the conductive thin wires.
[2] A step of forming a photosensitive layer containing silver halide, a physical development nucleus, and a polymer latex on a support, a conductive layer containing metallic silver by exposing the photosensitive layer and developing it. A method for producing a conductive sheet, comprising: a step of forming a conductive layer composed of a conductive fine wire; and a step of forming a film of the polymer latex by heat treatment after the development treatment to form a binder portion between the conductive thin wires.
[3] A step of forming a non-photosensitive layer containing a physical development nucleus and a polymer latex on a support, a step of forming a photosensitive layer containing silver halide on the non-photosensitive layer, After exposing the photosensitive layer, the step of forming a conductive layer composed of conductive fine wires containing metallic silver by diffusion transfer development processing, the step of removing the photosensitive layer, and the heating treatment after the development processing, the polymer latex A method for producing a conductive sheet, comprising a step of forming a binder portion between the conductive thin wires by forming a film.

[Support]
The support used in the present invention is preferably a transparent support, and a plastic film, a plastic plate, a glass plate and the like can be used, and a plastic film is preferable. By using a transparent support, the conductive sheet of the present invention can be suitably used as a transparent conductive sheet.
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 the photosensitive layer containing silver halide is provided on the 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 material]
The conductive sheet of the present invention can be obtained by exposing and developing a photosensitive material for producing a conductive sheet in which a photosensitive layer containing silver halide is formed on at least one surface of a support. The photosensitive material may have a protective layer on the photosensitive layer.
In the simplest configuration, the photosensitive material has a photosensitive layer on one surface of a support as shown in FIG. A protective layer may be provided on the photosensitive layer. Moreover, you may have a photosensitive layer on both surfaces of a support body like the photosensitive material 05 shown in FIG. FIG. 3 shows a structure having photosensitive layers on both sides of a support. An upper photosensitive material layer (also referred to as a front photosensitive material layer) 50 is provided on the back side of the support 32. A lower photosensitive material layer (also referred to as a back side photosensitive material layer) 60 is formed on the substrate. In the upper photosensitive material layer 50, an undercoat layer 56, an antihalation layer 57, an upper photosensitive layer containing silver halide (also referred to as a front surface photosensitive layer) 51, and a protective layer 55 are formed on a support 32. Yes. The undercoat layer, the antihalation layer, and the protective layer are layers provided as necessary. The upper photosensitive layer 51 may be formed of a photosensitive layer containing several silver halides and an intermediate layer between the photosensitive layers. The lower photosensitive material layer 60 may have the same layer structure as the upper photosensitive material layer 50.

[Photosensitive layer containing silver halide]
Next, a photosensitive layer containing silver halide will be described. In order to use developed silver as a conductive layer material, the type of photosensitive material and the type of development processing should be 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 conductive metal part (conductive film) such as an electrode made of a conductive thin wire 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 nuclei are dissolved and deposited on the development nuclei, whereby a conductive metal portion such as an electrode made of a conductive thin wire on the photosensitive material. (Conductive film) 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, thereby conducting the conductive metal such as an electrode made of a conductive thin wire on the image receiving sheet Part (conductive 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 simplest and stable treatment and is preferable for the production of the 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. More preferred are silver chlorobromide, silver bromide, silver iodochlorobromide and silver iodobromide, and most preferred are silver chlorobromide and silver iodochlorobromide containing 50 mol% or more of silver chloride. Used.

  Here, “silver halide mainly composed of silver bromide” refers to silver halide in which the molar fraction of bromide ions in the silver halide composition is 50% or more. The silver halide grains mainly composed of silver bromide may contain iodide ions and chloride ions in addition to bromide ions.

  The silver iodide content in the silver halide emulsion is preferably in a range not exceeding 1.5 mol% per mole of silver halide emulsion. 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.

  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.

  The silver halide emulsion used in the present invention is preferably a silver chlorobromide emulsion. Further, before development, in order to suppress fogging during development, a small amount of silver iodide is preferably contained, more preferably about 0.5 mol%. In the following, no indication is given even if silver iodide is included to the extent shown on the left.

  In the present invention, in order to adjust the reflection chromaticity of an electrode made of a conductive thin wire of developed silver formed after developing the photosensitive material 05 of the present invention, photosensitive layers 51 and 61 are provided as shown in FIG. The first photosensitive layer (u layer), the second photosensitive layer (m layer), and the third photosensitive layer (o layer) may be coated and formed as a photosensitive layer having a three-layer structure.

(binder)
In the photosensitive layer containing silver halide, a binder is used for the purpose of uniformly dispersing silver salt grains and assisting the adhesion between the emulsion layer and the support. As the binder, a water-soluble polymer is preferable, and gelatin is particularly preferable. Gelatin forms a binder part in the conductive sheet of the present invention together with the polymer latex described later. As the binder, instead of gelatin or together with gelatin, for example, carrageenan, polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), polysaccharides such as starch, cellulose and its derivatives, polyethylene oxide, polysaccharide, polyvinylamine, Chitosan, polylysine, polyacrylic acid, polyalginic acid, polyhyaluronic acid, carboxycellulose, gum arabic, sodium alginate and the like can be used, but 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.

The volume ratio of silver and gelatin contained in the photosensitive layer formed on the support of the present invention is preferably 1.0 or more, and more preferably 1.5 or more. By setting the volume ratio of silver and gelatin to 1.0 or more, the conductivity of the developed silver after the development process can be increased. The volume ratio of silver and gelatin in the present invention is calculated by calculating the mass of silver and the mass of binder contained in the silver halide emulsion layer. The density of silver is 10.5 g / cm ³ and the density of gelatin is 1.34 g. Calculated as / cm ³ .

(Polymer latex)
It is preferable that the binder part in the electrically conductive sheet of this invention contains what formed the polymer latex into a film by heat processing. The polymer particles contained in the polymer latex are heated to form a film, whereby a film with low water permeability can be formed, and moisture can be prevented from entering the binder part.

The heat treatment is preferably 40 ° C. or higher from the viewpoint of the film forming temperature of the polymer particles, more preferably 50 ° C. or higher, and still more preferably 60 ° C. or higher. Further, from the viewpoint of curling of the support, 150 ° C. or lower is preferable, and 100 ° C. or lower is more preferable.
The heating time is not particularly limited, but it is preferably 1 to 5 minutes, more preferably 1 to 3 minutes, from the viewpoint of productivity where the base does not curl.

  In the present invention, the heat treatment can be combined with a drying step usually performed after exposure and development processing, so there is no need to increase a new step for film formation of polymer particles, productivity, cost, etc. Excellent in terms of

Specific examples of the method for forming the binder part containing the polymer latex include the following (I) and (II).
(I): A conductive thin wire containing metallic silver by providing a photosensitive layer containing a silver halide and a polymer latex on a support, subjecting the photosensitive layer to exposure and development, and further heat treatment. Forming an electrode and a binder part.
(II): forming a non-photosensitive layer containing physical development nuclei and polymer latex on the support, and forming a peelable photosensitive layer containing silver halide on the non-photosensitive layer; The photosensitive layer is exposed and subjected to a diffusion transfer development process to transfer silver halide in an unexposed portion of the photosensitive layer to a physical development nucleus of the non-photosensitive layer, and from a conductive thin wire containing metallic silver. Forming an electrode, removing the photosensitive layer, and further heat-treating the non-photosensitive layer on which the electrode is formed.

The polymer contained in the polymer latex is represented by the following general formula (1) from the viewpoint of preventing moisture from entering the binder part and the layer adjacent to the binder part by forming a film having low water permeability. Preferred is a copolymer.
General formula (1):-(A) x- (B) y- (C) z- (D) w-
In general formula (1), A, B, C, and D represent the following monomer units, respectively. x, y, z, and w represent the molar ratio of each monomer unit, x is 3 to 60 (mol%), y is 30 to 96 (mol%), z is 0.5 to 25 (mol%), w represents 0.5 to 40 (mol%).

In the above formula,
R ¹ represents a methyl group or a halogen atom. p represents an integer of 0 to 2.
R ² represents a methyl group or an ethyl group.
R ³ represents a hydrogen atom or a methyl group. L represents a divalent linking group. q represents 0 or 1;
R ⁴ represents an alkyl group having 5 to 80 carbon atoms, an alkenyl group, or an alkynyl group.
R ⁵ represents a hydrogen atom, a methyl group, an ethyl group, a halogen atom, or —CH ₂ COOR ⁶ .
R ⁶ represents a hydrogen atom or an alkyl group having 1 to 80 carbon atoms.

In the monomer unit represented by the general formula (A), R ¹ represents a methyl group or a halogen atom, preferably a methyl group, a chlorine atom, or a bromine atom.
p represents an integer of 0 to 2, preferably 0 or 1, and more preferably 0.

In the monomer unit represented by the general formula (B), R ² represents a methyl group or an ethyl group, and a methyl group is preferable.

In the monomer unit represented by the general formula (C), R ³ represents a hydrogen atom or a methyl group, preferably a hydrogen atom.
L represents a divalent linking group, preferably a group represented by the following general formula (30).
Formula (30): — (CO—X ¹ ) r—X ² —
In the formula, X ¹ represents an oxygen atom or —NR ³⁰ —. Here, R ³⁰ represents a hydrogen atom, an alkyl group, an aryl group, or an acyl group, and each may have a substituent (for example, a halogen atom, a nitro group, a hydroxyl group, etc.). R ³⁰ is preferably a hydrogen atom, an alkyl group having 1 to 10 carbon atoms (for example, a methyl group, an ethyl group, an n-butyl group, an n-octyl group, etc.), an acyl group (for example, an acetyl group, a benzoyl group, etc.). is there. Particularly preferred as X ¹ is an oxygen atom or —NH—. r represents 0 or 1;

X ² represents an alkylene group, an arylene group, an alkylene arylene group, an arylene alkylene group, or an alkylene arylene alkylene group. These alkylene groups, arylene groups, alkylene arylene groups, arylene alkylene groups, and alkylene arylene alkylene groups are represented by —O. -, - S -, - OCO -, - CO -, - COO -, - NH -, - SO 2 -, - N (R 31) -, - N (R 31) SO 2 - , etc. is inserted in the middle May be. Here, R ³¹ represents a linear or branched alkyl group having 1 to 6 carbon atoms, such as a methyl group, an ethyl group, and an isopropyl group. Preferred examples of X ² include dimethylene group, trimethylene group, tetramethylene group, o-phenylene group, m-phenylene group, p-phenylene group, —CH ₂ CH ₂ OCOCH ₂ CH ₂ —, —CH ₂ CH ₂ OCO ( C ₆ H ₄ ) — and the like.
q represents 0 or 1, and 0 is preferable.

In the general formula (D), R ⁴ represents an alkyl group having 5 to 80 carbon atoms, an alkenyl group or an alkynyl group, preferably an alkyl group having 5 to 50 carbon atoms, more preferably 5 to 30 carbon atoms. It is an alkyl group, More preferably, it is a C5-C20 alkyl group.
R ⁵ represents a hydrogen atom, a methyl group, an ethyl group, a halogen atom, or —CH ₂ COOR ⁶ , preferably a hydrogen atom, a methyl group, a halogen atom, —CH ₂ COOR ⁶ , a hydrogen atom, a methyl group, —CH ₂ COOR ⁶ is more preferable, and a hydrogen atom is particularly preferable. R ⁶ is a hydrogen atom or an alkyl group having 1 to 80 carbon atoms, and may be the same as or different from R ^{4. The} number of carbon atoms in R ⁶ is preferably 1 to 70, more preferably 1 to 60.

The composition ratio of the polymer of the general formula (1) will be described.
x is 3 to 60 mol%, preferably 3 to 50 mol%, more preferably 3 to 40 mol%.
y is 30 to 96 mol%, preferably 35 to 95 mol%, particularly preferably 40 to 90 mol%.
If z is too small, the affinity with a hydrophilic protective colloid such as gelatin is reduced, so that the probability of occurrence of agglomeration / peeling failure of the matting agent increases, and if z is too large, it becomes an alkaline processing solution for photosensitive materials. The matting agent of the present invention is dissolved. Therefore, z is 0.5 to 25 mol%, preferably 0.5 to 20 mol%, particularly preferably 1 to 20 mol%.
As w, it is 0.5-40 mol%, Preferably it is 0.5-30 mol%.

In the general formula (1), it is particularly preferable that x is 3 to 40 mol%, y is 40 to 90 mol%, z is 0.5 to 20 mol%, and w is 0.5 to 30 mol%.
As the polymer represented by the general formula (1), a polymer containing a repeating unit represented by the following general formula (2) is preferable.

In the above formula, a, b, c and d represent the molar ratio of each monomer unit, a is 3 to 60 (mol%), b is 30 to 96 (mol%), and c is 0.5 to 25 ( Mol%) and d represent 0.5 to 40 (mol%).
The preferred range of a is the same as the preferred range of x, the preferred range of b is the same as the preferred range of y, the preferred range of c is the same as the preferred range of z, and the preferred range of d is The same as the preferable range of w.

The latex polymer in the present invention may contain monomer units other than the general formulas (A), (B), (C), and (D). Monomers for forming monomer units other than the general formulas (A), (B), (C), and (D) include acrylic acid esters, methacrylic acid esters, vinyl esters, olefins, and crotonic acid. Esters, itaconic acid diesters, maleic acid diesters, fumaric acid diesters, acrylamides, unsaturated carboxylic acids, allyl compounds, vinyl ethers, vinyl ketones, vinyl heterocycles, glycidyl esters, unsaturated nitriles, etc. Is mentioned. These monomers are also described in [0010] to [0022] of Japanese Patent No. 3754745.
From the viewpoint of hydrophobicity, acrylic acid esters and methacrylic acid esters are preferable, and hydroxyalkyl methacrylates such as hydroxyethyl methacrylate or hydroxyalkyl acrylates are more preferable. The latex polymer in the present invention preferably includes a monomer unit represented by the following general formula (E) in addition to the general formulas (A), (B), (C), and (D).

In the above formula, L _E represents an alkylene group.
Preferably L _E is an alkylene group having 1 to 10 carbon atoms, more preferably an alkylene group having 2 to 6 carbon atoms, more preferably an alkylene group having 2 to 4 carbon atoms.

  As the polymer represented by the general formula (1), a polymer represented by the following general formula (3) is particularly preferable.

In the above formula, a1, b1, c1, d1, and e1 represent the molar ratio of each monomer unit, a1 is 3 to 60 (mol%), b1 is 30 to 95 (mol%), and c1 is 0.5 to 25 (mol%), d1 represents 0.5 to 40 (mol%), and e1 represents 1 to 10 (mol%).
The preferred range of a1 is the same as the preferred range of x, the preferred range of b1 is the same as the preferred range of y, the preferred range of c1 is the same as the preferred range of z, and the preferred range of d1 is The same as the preferable range of w.
e1 is 1 to 10 mol%, preferably 2 to 9 mol%, more preferably 2 to 8 mol%.

  Although the specific example of the said General formula (1) is shown below, it is not limited to these.

  1000-1 million are preferable, as for the mass average molecular weight of the polymer represented by General formula (1), 2000-750,000 are more preferable, and 3000-500,000 are still more preferable.

  The polymer represented by the general formula (1) can be synthesized with reference to, for example, Japanese Patent No. 3305459 and Japanese Patent No. 3754745.

  The polymer latex preferably contains a polymer and a dispersant, and since the dispersant becomes an impurity, the content of the dispersant is preferably smaller from the viewpoint of migration, but it should not contain any dispersant. Is difficult from the viewpoint of dispersibility. Therefore, in the polymer latex, the content of the dispersant with respect to the polymer (the mass of the dispersant / the mass of the polymer) is preferably 5% or less (0.05 or less) from the viewpoint of dispersibility and migration, and preferably 3% or less ( 0.03 or less), preferably 1% or less (0.01 or less). Further, from the viewpoint of moisture content and impurities, 0.3% or more (0.003 or more) is preferable, and 0.5% or more (0.005 or more) is more preferable.

  In the present invention, the mass ratio of the polymer latex to the water-soluble polymer (polymer latex / water-soluble polymer) is preferably 1 or more from the viewpoint of water content and electrical conductivity at the time of film formation. 1 or more, more preferably 1.1 or more and 3.5 or less, still more preferably 1.5 or more and 3.5 or less, and more preferably 1.5 or more and 3.0 or less. It is particularly preferable that the ratio is 2.0 or more and 2.5 or less.

  In the present invention, the mass ratio (metal silver / polymer latex) of the metal silver and the polymer latex in the conductive layer is preferably 1 to 10 from the viewpoint of water content and conductivity, and preferably 2.3 to 7.5. Is more preferable, 2.6 to 5.2 is more preferable, 3.1 to 4 is particularly preferable, and 3.1 to 3.9 is most preferable.

  In the present invention, the mass ratio (metal silver / binder part) of metal silver and the binder part (total of polymer latex and water-soluble polymer) of the conductive layer is 1.8 from the viewpoint of water content and conductivity. It is preferably 3.8 or less, more preferably 2.0 or more and 3.1 or less, and further preferably 2.2 or more and 2.6 or less.

The solvent used for the formation of 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, etc. Sulfoxides such as sulfoxide, 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 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. Is preferred.

  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.

(Other layer structure)
In the present invention, a protective layer may be provided on the photosensitive layer. In the present embodiment, the “protective layer” means a layer composed of a water-soluble polymer such as gelatin or a hydrophobic polymer such as polymer latex, and is photosensitive to exhibit the effect of preventing scratches and improving mechanical properties. Formed on the photosensitive layer having the property. The thickness is preferably 0.05 μm or more and 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 protective layer preferably contains a water-soluble polymer (preferably gelatin) and a polymer latex, and the mass ratio of the polymer latex to the water-soluble polymer (polymer latex / water-soluble polymer) is preferably 1 or more. 1.1 or more, more preferably 1.1 or more and 3.5 or less, still more preferably 1.5 or more and 3.5 or less, and even more preferably 1.5 or more and 3.0 or less. Or less, and most preferably 2.0 or more and 2.5 or less.
In the present invention, the protective layer may be provided on the photosensitive layer before exposure and development processing. Further, the protective layer may be provided after the conductive layer and the binder part are formed, not on the photosensitive layer before the exposure and development processing.
Antihalation layers 57 and 67 can be provided between the photosensitive layer and the transparent support in the present invention. 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 exposure light, but is preferably about 0.5 to 3.0.
In the present invention, an undercoat layer other than the antihalation layer can be provided between the photosensitive layer and the transparent support.

Next, the process for producing the conductive sheet of the present invention using the material of the present invention described above will be described in more detail.
2A shows a transparent support 32, FIG. 2B shows a photosensitive material obtained by coating a photosensitive material layer 51 on the transparent support, and FIG. 2C shows a photosensitive material through a photomask (not shown). FIG. 2D is a schematic diagram in which an exposed portion 111 and an unexposed portion 112 are formed by exposure, and FIG. 4D shows a developed silver electrode 101 and a binder portion 102 formed by a development fixing process subsequent to exposure. Below, each process after exposure is demonstrated.

[exposure]
The photosensitive material in the present invention is a photosensitive material in which a photosensitive layer is formed on at least one surface of a transparent support. As shown in FIG. 2C, the light-sensitive material having the photosensitive layer is exposed by irradiating light. Light irradiation is performed on the photosensitive material through a photomask. The light transmitted through the opening of the mask forms a latent image on the silver halide emulsion of the photosensitive layer. The portion where the latent image is formed forms a developed silver pattern by the next development process. In the unexposed portion of the light-sensitive material that has not been exposed by the light-shielding portion of the mask, the silver halide emulsion grains that have not been exposed by the fixing process dissolve and flow out of the layer to form a transparent film.

(Development processing)
In the present embodiment, after the photosensitive layer is exposed, further development processing is performed. The development processing can be performed using 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. -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 a silver salt photographic film, photographic paper, a printing plate-making film, a photomask emulsion mask, or 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, 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.

(Heat treatment)
In the present invention, it is preferable to develop the photosensitive material and heat-treat the developed photosensitive material. By the heat treatment, film formation of a polymer latex can be performed. The preferable range of the temperature in the heat treatment is as described above. The heat treatment can also serve as a drying step.
The heat treatment is preferably performed at a relative humidity of 5% or more, more preferably a relative humidity of 50% or more from the viewpoint of swelling the water-soluble polymer (preferably gelatin) as a binder in addition to the preferable temperature range. More preferably, the humidity is 80% or more. Swelling of the water-soluble polymer is preferable because it facilitates film formation of a polymer latex.
The heat treatment can be performed by increasing the drying temperature after washing in the development step.

(Hardening after development)
It is preferable to perform a hardening process by performing a development process on the photosensitive layer and then immersing it in a hardening agent. 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.

(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.

(Xenon flash)
In the manufacturing method of the present embodiment, it is preferable to perform xenon flash on the transparent conductive sheet. By conducting xenon flash, the developed silver can be fused, and the conductivity and transparency can be easily improved in a short time.

(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. Further, the constituent material of the plating layer is preferably a metal having sufficient conductivity, and copper is preferable.
In the present invention, it is also preferable that the conductive thin wire contains an alloy of silver and copper.

(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.

(Silver hard solvent)
It is preferable that the transparent conductive sheet of this invention contains a silver difficult solvent further in a binder part, or the binder part is what was immersed in the silver difficult solvent. The ionization of the metal can be prevented by the silver difficult solvent, and the migration resistance is improved. As a silver difficult solvent, it is preferable that pKsp is 9 or more, and it is more preferable that it is 10-20. Although it does not specifically limit as a silver difficult solvent, For example, TTHA (triethylenetetramine hexaacetic acid) etc. are mentioned.
The solubility product Ksp of silver is a measure of the strength of interaction of these compounds with silver ions. The measurement method of Ksp is “Kiken Sakaguchi / Shinichi Kikuchi, Journal of the Japan Photography Society, 13, 126, (1951)” and “A. Paliofet and J. Pauladier, Bull. Soc. Chim. France, 1982, I-445 ( 1982) ".
The addition amount of the silver flame solvent, it is more preferable that it is ^preferable, is 1mg / ^{m 2} ~300mg / m 2 adsorption is ^1mg / ^{m 2 ~500mg} / m 2 adsorbed on the metal wiring portion.

The conductive sheet 10 made of conductive thin wires formed through the above process is a patterned electrode made of a plurality of conductive thin wires.
The line width of the conductive thin wires forming the conductive lattice portion is preferably 1 μm or more and 20 μm or less, and more preferably 2 μm or more and 6 μm or less. When the thickness is in the range of 1 μm or more and 20 μm or less, a low-resistance electrode can be formed relatively easily.
The thickness of the conductive thin wire 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 or less. When the thickness is in the range of 0.1 μm or more and 1.5 μm or less, an electrode having low resistance and excellent durability can be formed relatively easily.
The conductive pattern of the conductive thin wire of the present invention is a triangle such as a regular triangle, an isosceles triangle, a right triangle, a square, a rectangle, a rhombus, a parallelogram, a quadrangle such as a trapezoid, a (positive) hexagon, (positive) It is preferably a geometric figure combining (positive) n-gons such as an octagon, a circle, an ellipse, and a star, and more preferably a mesh shape composed of these geometric figures. When using a transparent conductive sheet as an electrode of a touch panel, a lattice pattern is preferable from the viewpoint of an aperture ratio and the like, and the length of one side of the conductive lattice portion is preferably 3 to 10 mm, and 4 to 6 mm. It is more preferable that 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.

Since the transparent conductive sheet of the present invention is excellent in moldability, it can be used for various applications.
When the electrical resistance value when the transparent conductive sheet of the present invention is stretched 100% is Rb, and the electrical resistance value (initial value) before stretching is R0, it is preferable that Rb ≦ (2 × R0) is satisfied. In order to obtain such a transparent conductive sheet, vacuum molding, pressure molding, hot press molding and the like are effective.

Next, the patterned electrode formed 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. In the conventional capacitive type 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, an electrode is formed by a combination of conductive thin wires using a material having a resistance lower than that of ITO. This is called a patterned electrode.
As shown in FIG. 4, the capacitive touch panel using the transparent conductive sheet of the present invention has an upper electrode (also referred to as a front electrode) 11 and a lower electrode (back surface) on both surfaces of the transparent support 32. (Also referred to as an electrode) 12 may be formed.
Alternatively, a capacitive touch panel using two transparent conductive sheets having electrodes on one surface as shown in FIGS.

  The conductive 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. Accordingly, when the conductive sheet of the present invention is used, for example, when applied to a projected capacitive touch panel, the response speed can be increased, and an increase in the size of the touch panel can be promoted.

  The transparent conductive sheet of the present invention can be used for various applications, and the application is not particularly limited. For example, various electrodes (for example, electrodes for touch panels, electrodes for inorganic EL elements, electrodes for organic EL elements, or solar cells) Electrode), a heat generating sheet, and a printed wiring board. The transparent conductive sheet of the present invention is preferably used for a touch panel, and particularly preferably for a capacitive touch panel. In addition, the conductive sheet of the present invention is a personal computer, an electronic medical device, or the like using an electromagnetic wave blocking net that blocks electromagnetic waves such as radio waves and microwaves (extremely short waves) generated from personal computers and workstations, and prevents static electricity. It can be used as a curtain that shields electromagnetic waves in a shield cover or room in a building. In addition, the conductive sheet of the present invention is flexible and has an antistatic effect, an antibacterial effect, and an antifungal effect. Further, it may be used as an electromagnetic shielding cover for a personal computer body, a shielding cover for a video photographing device, and a shielding cover for an electronic medical device.

  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. However, Japanese publications have hyphens after the year, as in 2004-221564, and international pamphlets have 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.

(Preparation of silver halide 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, 0.15 g of potassium iodide was added and ripened for 5 minutes to complete 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
5 ml of potassium hexachloroiridium (III) (0.005% KCl 20% aqueous solution)
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., and 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 0.08 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%.

(Preparation of photosensitive layer coating solution-1)
1,3,3a, 7-tetraazaindene 1.2 × 10 ⁻⁴ mol / mol Ag, hydroquinone 1.2 × 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 trace amount of hardener was added, and the coating solution pH was adjusted to 5.6 using citric acid. To prepare a photosensitive layer coating solution.
(Addition of polymer latex)
In the photosensitive layer coating solution, a polymer latex containing a dispersant represented by (P-1) and a dialkylphenyl PEO sulfate ester (dispersant / polymer mass ratio is 2.0) with respect to gelatin contained. /100=0.02) and latex / gelatin (mass ratio) = 0.5 / 1.
Photosensitive layer coating solution-1 was prepared as described above.

(Preparation of photosensitive material-1)
A 100 μm polyethylene terephthalate (PET) film was subjected to corona discharge treatment, and then a gelatin subbing layer having a thickness of 0.1 μm was provided as a support. The photosensitive layer coating solution-1 prepared and prepared above was applied to this support. The photosensitive layer (emulsion layer) of the obtained coated sample (photosensitive material-1) has a silver amount of 7.5 g / m ² , a ceratin amount of 0.95 g / m ² and a silver / gelatin volume ratio of the emulsion layer of 1 / 1

(Exposure and development processing)
As a migration evaluation sample, the photosensitive material-1 prepared above was exposed using parallel light using a high-pressure mercury lamp as a light source through a photomask capable of giving a developed silver image of the test pattern shown in FIG. The test pattern is a pattern based on IPC-TM650 or SM840, and has a line width of 50 μm, a space width of 50 μm, and the number of lines is 17/18 (hereinafter referred to as a comb pattern electrode). After exposure, development is performed with the following developer, development processing is further performed using a fixing solution (trade name: N3X-R for CN16X: manufactured by FUJIFILM Corporation), rinsing with pure water, and drying. A pattern electrode was obtained.
Next, as a sample for evaluating conductivity, the photosensitive material-1 prepared above was exposed using an exposure machine. A high pressure mercury lamp was used as the light source, and exposure was performed using a mask for forming a lattice pattern. In the light transmission window of the mask used, the unit square lattice forming the lattice has a line width of 3 μm and the side length of the lattice is 300 μm.
After exposure, the film was developed with the following developer, developed with a fixer (trade name: N3X-R for CN16X: manufactured by Fuji Film), rinsed with pure water, and dried. Thus, the electrode which consists of a conductive thin wire containing metallic silver was produced.

(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

(Heat treatment: Film formation of polymer latex)
The electrode composed of the comb pattern electrode and the conductive fine wire obtained above was heat-treated at 60 ° C./1 min in the drying step after washing with water in the development treatment. As a result of the heat treatment, a polymer latex contained in the binder part is formed.
In this way, a conductive pattern conductive sheet sample and a transparent conductive sheet sample 1 were prepared.

(Evaluation)
(1) Equilibrium moisture content after aging for 20 days at 60 ° C. and 90% RH in the binder part In order to measure the equilibrium moisture content in the binder part at 60 ° C. and 90% RH, 100 μm polyethylene terephthalate (PET) Each photosensitive layer coating solution prepared above was coated on a support provided with an undercoat layer on a film. The obtained light-sensitive material was subjected to the above development treatment without exposure, and only the silver halide was extracted, and the above heat treatment was performed, thereby preparing samples each having no electrode and no binder.
The equilibrium water content of the binder part at 60 ° C. and 90% RH was calculated as follows.
Moisture content of the binder part over time (%) = [{(W ₂₀ −W _S ) − (W ₁₀ −W _S )} / (W ₁₀ −W _S )] × 100
Here, W ₁₀ is the mass of the sample after aging at 120 ° C. for 4 hours (absolutely dry state), W ₂₀ is the mass of the sample after aging at 60 ° C. and 90% RH for 20 days, W _S is the mass of the PET film.

(2) Evaluation of migration resistance The following evaluation was performed on the comb pattern conductive sheet sample.
As shown in FIG. 8, the lines in the electronic circuit are insulated. A test was conducted to determine whether or not migration occurred over time with voltage applied to the electronic circuit. When migration occurs, a dendritic metal grows and short-circuits between lines, resulting in dielectric breakdown.
Wiring was connected to the electrodes (black portions in the figure) at both ends of the fabricated comb pattern electrode, and a direct current of 5 V DC was continuously applied from one side in a humid heat atmosphere of 60 ° C. and 90% RH. The test was temporarily interrupted, taken out from the atmosphere of 60 ° C. and 90% RH, applied with an applied voltage of 10 V DC using an R8340A manufactured by Advantest, and the insulating resistance value was measured.
In addition, the generation and growth of dendrites were observed with a microscope.
The insulation resistance was measured after 500 hours of application time and evaluated as follows.
○: Insulation resistance value is 10 ¹⁰ Ω or more △: Insulation resistance value is 10 ⁶ Ω or more and less than 10 ¹⁰ Ω ×: Insulation resistance value is less than 10 ⁶ Ω Also, dendrid occurs when the test is temporarily interrupted and observed It was confirmed whether it was doing and evaluated as follows.
○: Dendrite generated and no growth of 5 μm or more △: Dendrid generated, no growth of 5 μm or more ×: Dendrid generated

(3) Evaluation of conductivity The surface resistance value of the electrode of the transparent conductive sheet was directly read and evaluated according to the following criteria.
○: Less than 10 ² Ω / □ △: 10 ² Ω / □ or more, less than 10 ³ Ω / □ ×: 10 ³ Ω / □ or more, less than 10 ⁶ Ω / □ XX: Resistance value cannot be measured. 10 ⁶ Ω / □ or more

(Production of photosensitive material-2 to photosensitive material-9)
In preparation of the photosensitive layer coating solution-1, except that the polymer latex / gelatin (mass ratio) was changed as shown in Table 2 below, Photosensitive material-2 to Photosensitive material were prepared in the same manner as in the preparation of photosensitive material-1. -9 was produced.
(Preparation of comb pattern conductive sheet sample and transparent conductive sheet samples 2 to 9)
Using the photosensitive material-2 to photosensitive material-9, comb pattern conductive sheet samples and transparent conductive sheet samples 2 to 9 were prepared in the same manner as described above.

(Production of photosensitive material-10 to photosensitive material-17)
Photosensitive layer coating solution-1 was prepared in the same manner as photosensitive material-1, except that the type of polymer latex and the polymer latex / gelatin (mass ratio) were changed as shown in Table 2 below. Materials-10 to Photosensitive material-17 were prepared.
(Preparation of comb pattern conductive sheet sample and transparent conductive sheet samples 10 to 17)
Using the photosensitive material-10 to photosensitive material-17, comb pattern conductive sheet samples and transparent conductive sheet samples 10 to 17 were prepared in the same manner as described above.

(Preparation of comb pattern conductive sheet sample and transparent conductive sheet samples 18-24)
A comb-shaped pattern conductive sheet sample and a transparent conductive material were formed in the same manner except that a protective layer of gelatin and polymer latex composition as shown in Table 2 below was provided on the photosensitive layer of the photosensitive material-4 with a film thickness of 0.15 μm. Sheet samples 18 to 24 were produced. For the protective layer of Sample 18, only gelatin was used.
Moreover, about the samples 18-24, after providing the protective layer, the moisture content was computed by the said formula (including the moisture content of a protective layer).

(Production of Comb Pattern Conductive Sheet Sample and Transparent Conductive Sheet Sample 25-28)
For the comb pattern conductive sheet sample and the transparent conductive sheet sample 4 produced using the photosensitive material-4, the heating temperature in the heat treatment (polymer latex film formation) after development is changed as shown in Table 2 below. Except for the above, the same pattern conductive sheet sample and transparent conductive sheet samples 25 to 28 were prepared.

(Production of Comb Pattern Conductive Sheet Sample and Transparent Conductive Sheet Samples 29 to 32)
Using the photosensitive material-1 to photosensitive material-4, a comb pattern conductive sheet sample and a transparent conductive sheet sample were prepared in the same manner as described above, and then immersed in TTHA (triethylenetetramine hexaacetic acid) for 5 minutes. Comb pattern conductive sheet samples and transparent conductive sheet samples 29 to 32 washed with water for 1 minute were prepared.

(Production of Comb Pattern Conductive Sheet Sample and Transparent Conductive Sheet Samples 33-36)
Using the photosensitive material-1 to photosensitive material-4, a comb-shaped pattern conductive sheet sample and a transparent conductive sheet sample were prepared in the same manner as described above, and then copper plating was performed to form a comb-shaped pattern conductive sheet sample and a transparent conductive sheet. Samples 33 to 36 were produced.

  The comb pattern conductive sheet sample and the transparent conductive sheet samples 2 to 36 were also evaluated in the same manner as the sample 1. The results are shown in Table 2.

  From the above results, it can be seen that migration resistance can be imparted by setting the moisture content of the binder part to 10% or less in the transparent conductive sheet.

DESCRIPTION OF SYMBOLS 10 Conductive sheet 101 Conductive layer 102 Binder part 111 Exposure part 01 Touch panel 05 Photosensitive material 11 for manufacturing a transparent conductive sheet 11 Upper electrode (front surface electrode)
12 Lower electrode (back surface electrode)
21. Conductive fine wire 22 constituting upper electrode 22 Conductive fine wire 30, 31 constituting lower electrode Transparent support 32 also serving as touch surface Transparent support 33 for conductive sheet Transparent support 41, 42 Adhesive layer 50 also serving as 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 layer

Claims (15)

On a support, a conductive sheet comprising a conductive layer composed of conductive thin wires containing metallic silver, and a binder part existing between the conductive thin wires,
The water content of the binder part is 10% or less, and the surface resistance of the conductive layer is 1000 ohm / sq. And
The binder part contains a polymer latex and a water-soluble polymer,
The electrically conductive sheet whose mass ratio (metal silver / polymer latex) of the said metal silver and the said polymer latex is 2.3 or more.
However, the water content is the equilibrium water content after aging for 20 days at 60 ° C. and 90% RH, and is calculated by the weight method as follows.
Moisture content (%) of binder part = (W ₂ −W ₁ ) / W ₁ × 100
W ₁ is the mass of the binder part after aging at 120 ° C. for 4 hours (absolutely dried state), and W ₂ is the mass of the binder part after aging for 20 days at 60 ° C. and 90% RH.
When it has a protective layer on a conductive layer, a binder part also contains a protective layer.   The conductive sheet according to claim 1, wherein a mass ratio of the polymer latex to the water-soluble polymer (polymer latex / water-soluble polymer) is 1 or more.   The conductive sheet according to claim 2, wherein a mass ratio of the polymer latex to the water-soluble polymer (polymer latex / water-soluble polymer) is 1.5 to 3.5.   The conductive sheet according to any one of claims 1 to 3, wherein a mass ratio (metal silver / polymer latex) between the metal silver and the polymer latex is 2.3 to 7.5. On the support, a surface resistance of 1000 ohm / sq. A conductive layer which is the following, and a binder part having a water content of 10% or less present between the conductive thin wires, and the mass ratio of the metallic silver to the polymer latex (metal silver / polymer latex) is 2 A method for producing a conductive sheet that is 3 or more,
On a support, and the silver halide to form a photosensitive layer containing a binder comprising a polymer latex, exposing the photosensitive layer, you further heat treatment after development processing, conductive sheet manufacturing method of.
However, the water content is the equilibrium water content after aging for 20 days at 60 ° C. and 90% RH, and is calculated by the weight method as follows.
Moisture content (%) of binder part = (W ₂ −W ₁ ) / W ₁ × 100
W ₁ is the mass of the binder part after aging at 120 ° C. for 4 hours (absolutely dried state), and W ₂ is the mass of the binder part after aging for 20 days at 60 ° C. and 90% RH.
When it has a protective layer on a conductive layer, a binder part also contains a protective layer. The manufacturing method of the electrically conductive sheet of Claim 5 whose temperature in the said heat processing is 40 degreeC or more. The binder is a water-soluble polymer, wherein the weight ratio of the polymer latex and the water-soluble polymer (polymer latex / water-soluble polymer) is 1 or more, the production of conductive sheet according to claim 5 or 6 Way . The conductive sheet according to claim 1, wherein the water-soluble polymer is gelatin. The heat treatment is carried out at 40 ° C. or higher and a relative humidity of 5% or more, the conductive sheet manufacturing method according to any one of claims 5-7. The metallic silver and the mass ratio of the polymer latex is a (metallic silver / polymer latex) is from 2.3 to 7.5, according to claim 5-7, 9 conducting sheet manufacturing method according to any one of. Polymer in the polymer latex is a copolymer represented by the following general formula (1), a conductive sheet according to any one of claims 1 to 4 and 8.
General formula (1):-(A) x- (B) y- (C) z- (D) w-
In general formula (1), A, B, C, and D represent the following monomer units, respectively. x, y, z, and w represent the molar ratio of each monomer unit, x is 3 to 60 (mol%), y is 30 to 96 (mol%), z is 0.5 to 25 (mol%), w represents 0.5 to 40 (mol%).

In the above formula,
R ¹ represents a methyl group or a halogen atom. p represents an integer of 0 to 2.
R ² represents a methyl group or an ethyl group.
R ³ represents a hydrogen atom or a methyl group. L represents a divalent linking group. q represents 0 or 1;
R ⁴ represents an alkyl group having 5 to 80 carbon atoms, an alkenyl group, or an alkynyl group.
R ⁵ represents a hydrogen atom, a methyl group, an ethyl group, a halogen atom, or —CH ₂ COOR ⁶ .
R ⁶ represents a hydrogen atom or an alkyl group having 1 to 80 carbon atoms. The polymer latex further contains a dispersant, and the mass ratio of the dispersant to the polymer in the polymer latex (dispersant / polymer) is 0.05 or less, any one of claims 1 to 4 , 8 , 11 The conductive sheet according to claim 1. The silver binder is further contained in the binder part, or the binder part is subjected to a dipping treatment in a silver difficult solvent, any one of claims 1 to 4 , 8, 11, and 12. Conductive sheet. The electrical resistance value when the conductive sheet is stretched 100% is Rb, and when the electrical resistance value (initial value) before stretching is R0, Rb ≦ (2 × R0) is satisfied , The conductive sheet according to any one of 8, 11 to 13 . A capacitive touch panel using the conductive sheet according to any one of claims 1 to 4, 8 , 11 to 14 .

Images