JP5638027B2 - Conductive sheet and capacitive touch panel - Google Patents

Description

  The present invention relates to a conductive sheet and a capacitive touch panel, and for example, relates to a conductive sheet and a capacitive touch panel used for a projected capacitive touch panel.

  As for the transparent conductive film using a thin metal wire, for example, as disclosed in Patent Documents 1 and 2, research continues.

  Recently, the touch panel has attracted attention. The touch panel is mainly applied to a small size such as a PDA (personal digital assistant) or a mobile phone, but it is considered that the touch panel will be increased in size by application to a display for a personal computer.

  In such a future trend, the conventional electrode uses ITO (indium tin oxide). ITO has a problem that the resistance increases and the transmission speed of the current between the electrodes decreases as the application size increases, and the response speed (the time from when the fingertip is touched until the position is detected) is delayed.

  Therefore, it is conceivable to reduce the surface resistance by arranging an electrode by arranging a large number of grids made of metal fine wires (metal fine wires). For example, Patent Documents 3 to 8 are known as touch panels using metal fine wires as electrodes.

US Patent Application Publication No. 2004/0229028 International Publication No. 2006/001461 Pamphlet JP-A-5-224818 International Publication No. 1995/27334 Pamphlet US Patent Application Publication No. 2004/0239650 US Pat. No. 7,202,859 International Publication No. 1997/18508 Pamphlet JP 2003-099185 A

  The present inventors have studied various configurations of the mesh electrode. It was found that when the disconnection portion was formed in the mesh electrode, the disconnection portion was conspicuous depending on the position of the disconnection portion. For example, it is formed at the intersection of a plurality of conductor lines forming a mesh electrode. For this reason, the open portion of the disconnection portion is opened as it is. By arranging the openings (disconnected portions) on a straight line, the disconnected portions are recognized as a pattern, which may cause visibility problems.

  The present invention has been made in consideration of such problems, and an object thereof is to provide a conductive sheet and a capacitive touch panel without impairing visibility.

  The conductive sheet of the present invention includes a base body having a first main surface and a second main surface, and a first electrode pattern disposed on the first main surface, wherein the first electrode pattern intersects a plurality of metals. A plurality of first conductive patterns, each of which is composed of a plurality of fine lines and extends in the first direction, and a plurality of first non-conductive patterns that electrically separate the plurality of first conductive patterns are provided alternately. The conductive pattern has a first disconnected portion in addition to the intersecting portion of the thin metal wires, and includes a second electrode pattern disposed on the second main surface, and the second electrode pattern includes a plurality of lattices formed by a plurality of intersecting thin metal wires. Comprising a plurality of second conductive patterns extending in a second direction orthogonal to the first direction and a plurality of second non-conductive patterns for electrically separating the plurality of second conductive patterns, The conductive pattern is the second disconnection in addition to the intersection of the fine metal wires So that the plurality of first conductive patterns and the plurality of second conductive patterns are orthogonal to each other when viewed from above, and the first electrode pattern lattice and the second electrode pattern lattice form a small lattice. One electrode pattern and a second electrode pattern are disposed on the substrate.

  The conductive sheet of the present invention includes a first base having a first main surface and a second main surface, and a first electrode pattern disposed on the first main surface of the first base, and the first electrode pattern Is composed of a plurality of grids made of a plurality of intersecting fine metal wires, and alternately includes a plurality of first conductive patterns extending in the first direction and a plurality of first non-conductive patterns electrically separating the plurality of first conductive patterns. The first non-conductive pattern has a first disconnected portion in addition to the intersecting portion of the thin metal wires, a second base having a first main surface and a second main surface, and a first base of the second base A second electrode pattern disposed on the main surface, the second electrode pattern comprising a plurality of grids made of a plurality of intersecting metal fine wires, and a plurality of second conductive patterns extending in a second direction orthogonal to the first direction; A plurality of second non-conductive patterns electrically separating the plurality of second conductive patterns; The second non-conductive pattern has a second disconnected portion in addition to the intersecting portion of the fine metal wires, and the plurality of first conductive patterns and the plurality of second conductive patterns are orthogonal to each other in a top view, and The first substrate and the second substrate are arranged so that a small lattice is formed by the lattice of the first electrode pattern and the lattice of the second electrode pattern.

  In the conductive sheet according to another aspect of the present invention, preferably, the first disconnection portion is located near the center of the intersection of the thin metal wires of the first nonconductive pattern, and the second disconnection portion is the second nonconductive. It is located in the vicinity of the center of the intersection of the fine metal wires of the pattern.

  In the conductive sheet according to another aspect of the present invention, preferably, the widths of the first disconnection portion and the second disconnection portion exceed the line width of the thin metal wire and are 50 μm or less.

  In the conductive sheet according to another aspect of the present invention, preferably, in the top view, the thin metal wire of the second conductive pattern is positioned in the first disconnection portion of the first nonconductive pattern, and the second nonconductive pattern The thin metal wire of the first conductive pattern is positioned at the second disconnection portion.

  In the conductive sheet according to another aspect of the present invention, preferably, the width of the thin metal wire of the first conductive pattern and the thin metal wire of the second conductive pattern is a, the first disconnected portion of the first non-conductive pattern, and the second When the width of the second disconnected portion of the non-conductive pattern is b, the relational expression ba−30 ≦ 30 μm is satisfied.

  In the conductive sheet according to another aspect of the present invention, preferably, the width of the thin metal wire of the first conductive pattern and the thin metal wire of the second conductive pattern is a, the first disconnected portion of the first non-conductive pattern, and the second When the width of the second disconnected portion of the non-conductive pattern is b, the relational expression (ba) / a ≦ 6 is satisfied.

  In the conductive sheet according to another aspect of the present invention, preferably, the misalignment between the center position of the thin metal wire of the first conductive pattern and the center position of the second disconnected portion of the second non-conductive pattern, and the metal of the second conductive pattern. The positional deviation between the center position of the thin line and the center position of the first disconnected portion of the first non-conductive pattern has a standard deviation of 10 μm or less.

  In the conductive sheet according to another aspect of the present invention, the lattice of the first electrode pattern and the lattice of the second electrode pattern have a lattice pitch of 250 μm to 900 μm, preferably a lattice pitch of 300 μm to 700 μm. The small lattice has a lattice pitch of 125 μm to 450 μm, preferably a lattice pitch of 150 μm to 350 μm.

  In the conductive sheet according to another aspect of the present invention, preferably, the fine metal wire constituting the first electrode pattern and the fine metal wire constituting the second electrode pattern have a line width of 30 μm or less.

  In the conductive sheet according to another aspect of the present invention, preferably, the lattice of the first electrode pattern and the lattice of the second electrode pattern have a rhombus shape.

  The capacitive touch panel of the present invention has the conductive sheet.

  According to the conductive sheet and the capacitive touch panel of the present invention, a reduction in visibility can be suppressed.

The disassembled perspective view which abbreviate | omits and shows the electrically conductive sheet for touchscreens partially. FIG. 2A is a cross-sectional view showing an example of a conductive sheet for a touch panel with a part thereof omitted. FIG. 2B is a cross-sectional view illustrating another example of the conductive sheet for a touch panel with a part thereof omitted. The top view which shows the example of the 1st electrode pattern formed in a 1st conductive sheet. The top view which shows the example of the 2nd electrode pattern formed in a 2nd conductive sheet. The top view which abbreviate | omits and shows the example which made the conductive sheet for touchscreens combining the 1st conductive sheet and the 2nd conductive sheet. Schematic which shows the positional relationship of a metal fine wire and a disconnection part. Schematic which shows the relationship between the center position of a metal fine wire, and the center position of a disconnection part.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The present invention will be described by the following preferred embodiments, but can be modified in many ways without departing from the scope of the present invention, and other embodiments than the present embodiment are utilized. be able to. Accordingly, all modifications within the scope of the present invention are included in the claims. In the present specification, a numerical range represented by using “to” means a range including numerical values described before and after “to”.

  Hereinafter, the conductive sheet and the capacitive touch panel according to the present embodiment will be described with reference to FIGS. In the present specification, “˜” indicating a numerical range is used as a meaning including numerical values described before and after the numerical value as a lower limit value and an upper limit value.

  As shown in FIGS. 1 and 2A, the conductive sheet for a touch panel according to the present embodiment (hereinafter referred to as the conductive sheet 10 for a touch panel) includes a first conductive sheet 12A and a second conductive sheet 12B. It is constructed by stacking.

  As shown in FIGS. 1 and 3, the first conductive sheet 12 </ b> A has a first electrode pattern 16 </ b> A formed on one main surface of the first transparent substrate 14 </ b> A (see FIG. 2A). The first electrode pattern 16A is composed of a number of grids made of fine metal wires. Each of the first electrode patterns 16A extends in the first direction (x direction) and is arranged in a second direction (y direction) perpendicular to the first direction, and each of the two or more first conductive patterns 18A, A first non-conductive pattern 20A that electrically isolates the first conductive pattern 18A. In the first non-conductive pattern 20A, a plurality of disconnection portions 22A (referred to as first disconnection portions 22A as necessary) are formed in addition to the intersections of the thin metal wires. Each first conductive pattern 18A is electrically separated by the plurality of disconnected portions 22A.

  The fine metal wires constituting the first electrode pattern 16A have a line width of 0.5 μm to 30 μm. Regarding the line width of the fine metal wire, it is 30 μm or less, preferably 15 μm or less, more preferably 10 μm or less, more preferably 9 μm or less, more preferably 7 μm or less, and preferably 0.5 μm or more. Although the first conductive pattern 18A and the first non-conductive pattern 20A have substantially the same line width, in FIG. 3, in order to clarify the first conductive pattern 18A and the first non-conductive pattern 20A, first The line width of the conductive pattern 18A is widened, and the line width of the first non-conductive pattern 20A is narrowed and exaggerated. The line width of the first conductive pattern 18A and the line width of the first non-conductive pattern 20A may be the same or different. Preferably, both line widths are the same. The reason is that the visibility may deteriorate if the line width is different. The fine metal wires of the first electrode pattern 16A are made of a metal material such as gold, silver, or copper, or a conductive material such as a metal oxide.

  The first electrode pattern 16A includes a plurality of grids 24A made up of intersecting fine metal wires. The lattice 24A includes an opening region surrounded by fine metal wires. The grating 24A has a grating pitch Pa of 250 μm to 900 μm, preferably a grating pitch Pa of 300 μm to 700 μm. The grid 24A of the first conductive pattern 18A and the grid 24A of the first non-conductive pattern 20A have substantially the same size.

  The grid 24A of the first non-conductive pattern 20A has a disconnected portion 22A in addition to the intersecting portion of the fine metal wires. It is not necessary for all the grids 24A constituting the first non-conductive pattern 20A to have the disconnection portions 22A. It is only necessary that the first non-conductive pattern 20A can achieve electrical separation between the adjacent first conductive patterns 18A. The length of the disconnected portion 22A is preferably 60 μm or less, more preferably 10 to 50 μm, 15 to 40 μm, and 20 to 40 μm. Further, the range in which the disconnection portion 22A is formed can be expressed by, for example, variation in linear density. Here, the variation in the line density is the variation in the total fine line length in the unit small lattice, and can be defined as ± (total line length maximum value−total line length minimum value) / total line length average value / 2 (%). . The range in which the disconnection portion 22A is formed is preferably ± 15% due to variations in cotton density, more preferably ± 10%, and even more preferably ± 0.5% to ± 5%.

  In the conductive sheet 10 for a touch panel described above, the grid 24A has a substantially rhombus shape. Here, the substantially rhombus shape means a parallelogram whose diagonal lines are substantially orthogonal. However, other polygonal shapes may be used. Further, the shape of one side may be a curved shape or a circular arc shape in addition to a linear shape. In the case of an arc shape, for example, two opposing sides may be outwardly convex arc shapes, and the other two opposing sides may be inwardly convex arc shapes. The shape of each side may be a wavy shape in which an outwardly convex arc and an inwardly convex arc are continuous. Of course, the shape of each side may be a sine curve.

  Each first conductive pattern 18A includes wide portions and narrow portions that are alternately arranged along the first direction (x direction). Similarly, each first non-conductive pattern 20A includes wide portions and narrow portions that are alternately arranged along the first direction (x direction). The order of the wide portion and the narrow portion of the first conductive pattern 18A is opposite to the order of the wide portion and the narrow portion of the first non-conductive pattern 20A.

  One end of each first conductive pattern 18A is electrically connected to the first external wiring 62A via the first terminal 60A. On the other hand, the other end of each first conductive pattern 18A is an open end.

  As shown in FIGS. 1 and 4, the second conductive sheet 12 </ b> B has a second electrode pattern 16 </ b> B formed on one main surface of the second transparent substrate 14 </ b> B (see FIG. 2A). The second electrode pattern 16B is composed of a number of grids made of fine metal wires. Each of the second electrode patterns 16B extends in the second direction (y direction) and is arranged in a first direction (x direction) orthogonal to the second direction. A second non-conductive pattern 20B that electrically isolates the second conductive pattern 18B. In the second non-conductive pattern 20B, a plurality of disconnection portions 22B (referred to as second disconnection portions 22B as necessary) are formed in addition to the intersections of the fine metal wires. The second conductive patterns 18B are electrically separated by the plurality of disconnected portions 22B.

  The fine metal wire constituting the second electrode pattern 16B has a line width of 0.5 μm to 30 μm. Regarding the line width of the fine metal wire, it is 30 μm or less, preferably 15 μm or less, more preferably 10 μm or less, more preferably 9 μm or less, more preferably 7 μm or less, and preferably 0.5 μm or more. The second conductive pattern 18B and the second non-conductive pattern 20B have substantially the same line width. In FIG. 4, the second conductive pattern 18B and the second non-conductive pattern 20B are shown in order to clarify the second conductive pattern 18B and the second non-conductive pattern 20B. The line width of the conductive pattern 18B is widened and the line width of the second non-conductive pattern 20B is narrowed and exaggerated. The line width of the second conductive pattern 18B and the line width of the second non-conductive pattern 20B may be the same or different. Preferably, both line widths are the same. The reason is that the visibility may deteriorate if the line width is different. The fine metal wires of the first electrode pattern 16A are made of a metal material such as gold, silver, or copper, or a conductive material such as a metal oxide.

  The second electrode pattern 16B includes a plurality of grids 24B made up of intersecting fine metal wires. The lattice 24B includes an opening region surrounded by fine metal wires. The grating 24B has a grating pitch Pb of 250 μm to 900 μm, preferably a grating pitch Pb of 300 μm to 700 μm. The grid 24B of the second conductive pattern 18B and the grid 24B of the second non-conductive pattern 20B have substantially the same size.

The grid 24B of the second non-conductive pattern 20B has a disconnected portion 22B in addition to the intersecting portion of the fine metal wires. It is not necessary for all the lattices 24B constituting the second non-conductive pattern 20B to have the disconnected portion 22B. It is only necessary that the second non-conductive pattern 20B can achieve electrical separation between the adjacent second conductive patterns 18B. The length of the disconnected portion 22B is preferably 60 μm or less, more preferably 10 to 50 μm, 15 to 40 μm, and 20 to 40 μm. Further, the range in which the disconnection portion 22B is formed can be expressed by, for example, variation in linear density. Here, the variation in the line density is the variation in the total fine line length in the unit small lattice, and can be defined as ± (total line length maximum value−total line length minimum value) / total line length average value / 2 (%). . The range in which the disconnection portion 22B is formed is preferably ± 15% due to variations in cotton density, more preferably ± 10%, and even more preferably ± 0.5% to ± 5%.
It is.

  In the touch panel conductive sheet 10 described above, the lattice 24B has a substantially rhombus shape. Here, the substantially rhombus shape means a parallelogram whose diagonal lines are substantially orthogonal. However, other polygonal shapes may be used. Further, the shape of one side may be a curved shape or a circular arc shape in addition to a linear shape. In the case of an arc shape, for example, two opposing sides may be outwardly convex arc shapes, and the other two opposing sides may be inwardly convex arc shapes. The shape of each side may be a wavy shape in which an outwardly convex arc and an inwardly convex arc are continuous. Of course, the shape of each side may be a sine curve.

  Each of the second conductive patterns 18B includes wide portions and narrow portions that are alternately arranged along the second direction (y direction). Similarly, each second non-conductive pattern 20B includes wide portions and narrow portions that are alternately arranged along the second direction (y direction). The order of the wide portion and the narrow portion of the second conductive pattern 18B is opposite to the order of the wide portion and the narrow portion of the second non-conductive pattern 20B.

  One end of each second conductive pattern 18B is electrically connected to the second external wiring 62B via the second terminal 60B. On the other hand, the other end of each second conductive pattern 18B is an open end.

  For example, when the first conductive sheet 12A is laminated on the second conductive sheet 12B to form the touch panel conductive sheet 10, the first electrode pattern 16A and the second electrode pattern 16B overlap as shown in FIG. Not arranged. At this time, the narrow portion of the first conductive pattern 18A and the narrow portion of the second conductive pattern 18B face each other, and the narrow portion of the first conductive pattern 18A and the second conductive pattern 18B intersect. The first electrode pattern 16A and the second electrode pattern 16B are disposed. As a result, the combination pattern 70 is formed by the first electrode pattern 16A and the second electrode pattern 16B. Note that the line widths of the first electrode pattern 16A and the second electrode pattern 16B are substantially the same. In addition, the sizes of the lattice 24A and the lattice 24B are substantially the same. However, in FIG. 5, in order to clarify the positional relationship between the first electrode pattern 16A and the second electrode pattern 16B, the line width of the first electrode pattern 16A is displayed wider than the line width of the second electrode pattern 16B. .

  In the combination pattern 70, a small lattice 76 is formed by the lattice 24A and the lattice 24B in a top view. That is, the intersection of the grating 24A is arranged in the opening area of the grating 24B. The small lattice 76 has a lattice pitch Ps of 125 μm to 450 μm, which is half of the lattice pitches Pa and Pb of the lattice 24A and the lattice 24B, and preferably has a lattice pitch Ps of 150 μm to 350 μm.

  The disconnected portion 22A of the first non-conductive pattern 20A is formed at a portion other than the intersection of the lattice 24A, and the disconnected portion 22B of the second non-conductive pattern 20B is formed at a portion other than the intersection of the lattice 24B. As a result, in the combination pattern 70, it is possible to prevent the deterioration of visibility due to the disconnection portion 22A and the disconnection portion 22B.

  In particular, the fine metal wire of the second conductive pattern 18B is disposed at a position facing the disconnection portion 22A. In addition, a fine metal wire of the first conductive pattern 18A is disposed at a position facing the disconnection portion 22B. The fine metal wire of the second conductive pattern 18B masks the disconnection portion 22A, and the fine metal wire of the first conductive pattern 18A masks the disconnection portion 22B. Therefore, in the combination pattern 70, the disconnection portion 22A and the disconnection portion 22B are hardly visually recognized in a top view, and thus visibility can be improved. Considering the improvement in visibility, it is preferable that the length of the disconnected portion 22A and the line width of the thin metal wire of the second conductive pattern 18B satisfy the relational expression of line width × 1 <disconnected portion <line width × 10. Similarly, it is preferable that the length of the disconnection portion 22B and the line width of the thin metal wire of the first conductive pattern 18A satisfy the relational expression of line width × 1 <disconnection portion <line width × 10.

  Next, the relationship between the 2nd disconnection part 22B and the thin metal wire of the 1st conductive pattern 18A and the relationship between the 1st disconnection part 22A and the thin metal wire of the 2nd conductive pattern 18B are demonstrated. FIG. 6 is a schematic diagram showing the positional relationship between the fine metal wire and the broken portion. The width of the fine metal wire of the first conductive pattern 18A and the fine metal wire of the second conductive pattern 18B is a, and the first disconnected portion 22A of the first nonconductive pattern 20A and the second disconnected portion 22B of the second nonconductive pattern 20B. It is preferable that the relational expression b−a ≦ 30 μm is satisfied, where b is the width of. The smaller the difference between the width of the fine metal wire and the width of the broken wire portion, the more the broken wire portion is occupied by the fine metal wire, and the deterioration of visibility can be prevented.

  Further, the width of the fine metal wire of the first conductive pattern 18A and the fine metal wire of the second conductive pattern 18B is a, and the first disconnected portion 22A of the first non-conductive pattern 20A and the second disconnection of the second non-conductive pattern 20B. When the width of the portion 22B is b, it is preferable to satisfy the relational expression (ba) / a ≦ 6. This is because the width of the second disconnected portion 22B of the second non-conductive pattern 20B is equal to or less than a predetermined width with respect to the width of the fine metal wire of the first conductive pattern 18A and the thin metal wire of the second conductive pattern 18B. means. Similarly to the above, it means that the disconnection portion is occupied as much as possible by the fine metal wire, and deterioration of visibility can be prevented.

  Next, the positional deviation between the center position of the fine metal wire and the center position of the disconnection portion will be described. FIG. 7 is a schematic diagram showing the relationship between the center position of the fine metal wire and the center position of the disconnection portion. The center line CL1 indicates the center position of the fine metal wire of the first conductive pattern 18A or the fine metal wire of the second conductive pattern 18B. The center line CL2 indicates the center position of the second disconnection portion 22B or the first disconnection portion 22A. The shift amount d means the distance between the center line CL1 and the center line CL2. The standard deviation σ is preferably 10 μm or less, where the deviation amount d is the average value of the deviation amounts d and dAve. The small standard deviation σ means that the variation in the deviation amount d between the center line CL1 and the center line CL2 is small. When the thin metal wire is located at the center of the disconnection as much as possible, the distance between L1 and L2, which is the gap between the thin metal wire of the first conductive pattern 18A and the thin metal wire of the second non-conductive pattern 20B, becomes equal. Alternatively, the distances between L1 and L2, which are the gaps between the fine metal wires of the second conductive pattern 18B and the fine metal wires of the first non-conductive pattern 20A, are equal. When it has objectivity, it becomes difficult to recognize human visibility, and as a result, deterioration of visibility can be prevented.

  When this conductive sheet for touch panel 10 is used as a touch panel, a protective layer (not shown) is formed on the first conductive sheet 12A. The first external wiring 62A derived from a large number of first conductive patterns 18A of the first conductive sheet 12A and the second external wiring 62B derived from a large number of second conductive patterns 18B of the second conductive sheet 12B include, for example, It is connected to an IC circuit that controls scanning.

  In the conductive sheet 10 for the touch panel, each connection portion between the first conductive pattern 18A and the first external wiring 62A is preferably linear so that the area of the outer peripheral region that is removed from the display screen of the liquid crystal display device is minimized. The connecting portions between the second conductive pattern 18B and the second external wiring 62B are arranged in a straight line.

  By bringing the fingertip into contact with the protective layer, the capacitance between the first conductive pattern 18A and the second conductive pattern 18B facing the fingertip changes. The IC circuit detects the amount of change and calculates the position of the fingertip based on the amount of change. This calculation is performed between the first conductive pattern 18A and the second conductive pattern 18B. Therefore, it is possible to detect the position of each fingertip even if two or more fingertips are brought into contact with each other at the same time.

  Thus, in the conductive sheet 10 for a touch panel, when the conductive sheet 10 for a touch panel is applied to, for example, a projected capacitive touch panel, the response speed can be increased because the surface resistance is small. The touch panel can be increased in size.

  Next, a method for manufacturing the first conductive sheet 12A and the second conductive sheet 12B will be described.

  When manufacturing the first conductive sheet 12A and the second conductive sheet 12B, for example, a photosensitive material having an emulsion layer containing a photosensitive silver halide salt on the first transparent substrate 14A and the second transparent substrate 14B is exposed. By performing the development process, the first electrode pattern 16A and the second electrode pattern 16B are formed by forming a metal silver portion (metal fine line) and a light transmissive portion (opening region) in the exposed portion and the unexposed portion, respectively. You may do it. In addition, you may make it carry | support a conductive metal to a metal silver part by giving a physical development and / or a plating process to a metal silver part further.

  Alternatively, the photoresist film on the copper foil formed on the first transparent substrate 14A and the second transparent substrate 14B is exposed and developed to form a resist pattern, and the copper foil exposed from the resist pattern is etched. The first electrode pattern 16A and the second electrode pattern 16B may be formed.

  Alternatively, the first electrode pattern 16A and the second electrode pattern 16B are formed by printing a paste containing metal fine particles on the first transparent substrate 14A and the second transparent substrate 14B and performing metal plating on the paste. Also good.

  The first electrode pattern 16A and the second electrode pattern 16B may be printed and formed on the first transparent substrate 14A and the second transparent substrate 14B by a screen printing plate or a gravure printing plate. Alternatively, the first electrode pattern 16A and the second electrode pattern 16B may be formed by inkjet on the first transparent substrate 14A and the second transparent substrate 14B.

  As shown in FIG. 2B, when the first electrode pattern 16A is formed on one main surface of the first transparent substrate 14A and the second electrode pattern 16B is formed on the other main surface of the first transparent substrate 14A, In accordance with the manufacturing method, if the method of exposing one principal surface first and then exposing the other principal surface is adopted, the first electrode pattern 16A and the second electrode pattern 16B having a desired pattern cannot be obtained. There is a case.

  Therefore, the following manufacturing method can be preferably employed.

  That is, the photosensitive silver halide emulsion layer formed on both surfaces of the first transparent substrate 14A is collectively exposed to form the first electrode pattern 16A on one main surface of the first transparent substrate 14A. A second electrode pattern 16B is formed on the other main surface of the transparent substrate 14A.

  A specific example of this manufacturing method will be described.

  First, a long photosensitive material is prepared. The photosensitive material includes a first transparent substrate 14A, a photosensitive silver halide emulsion layer (hereinafter referred to as a first photosensitive layer) formed on one main surface of the first transparent substrate 14A, and the other of the first transparent substrate 14A. A light-sensitive silver halide emulsion layer (hereinafter referred to as a second photosensitive layer) formed on the main surface.

  Next, the photosensitive material is exposed. In this exposure process, the first photosensitive layer is irradiated with light toward the first transparent substrate 14A to expose the first photosensitive layer along the first exposure pattern, and the second photosensitive layer is exposed. On the other hand, a second exposure process is performed in which light is irradiated toward the first transparent substrate 14A to expose the second photosensitive layer along the second exposure pattern (double-sided simultaneous exposure).

  For example, while conveying a long photosensitive material in one direction, the first photosensitive layer is irradiated with the first light (parallel light) through the first photomask, and the second photosensitive layer is irradiated with the second light (parallel light). ) Through the second photomask. The first light is obtained by converting the light emitted from the first light source into parallel light by the first collimator lens in the middle, and the second light is obtained by converting the light emitted from the second light source in the middle of the first light. It is obtained by being converted into parallel light by a two-collimator lens.

  In the above description, the case where two light sources (the first light source and the second light source) are used is shown, but the light emitted from one light source is divided through the optical system, and the first light and the second light are divided. The first photosensitive layer and the second photosensitive layer may be irradiated as light.

  Next, by developing the exposed photosensitive material, a conductive sheet 10 for a touch panel is produced, for example, as shown in FIG. The conductive sheet 10 for a touch panel includes a first transparent substrate 14A, a first electrode pattern 16A along a first exposure pattern formed on one main surface of the first transparent substrate 14A, and the first transparent substrate 14A. And a second electrode pattern 16B along the second exposure pattern formed on the other main surface. In addition, since the exposure time and development time of the first photosensitive layer and the second photosensitive layer vary depending on the types of the first light source and the second light source, the type of the developer, and the like, the preferable numerical range should be determined unambiguously. However, the exposure time and the development time are adjusted so that the development rate becomes 100%.

  In the manufacturing method according to the present embodiment, the first exposure process includes, for example, arranging a first photomask on the first photosensitive layer in close contact with the first light source arranged opposite to the first photomask. The first photosensitive layer is exposed by irradiating the first light toward one photomask. The first photomask is composed of a glass substrate formed of transparent soda glass and a mask pattern (first exposure pattern) formed on the glass substrate. Accordingly, the first exposure process exposes a portion of the first photosensitive layer along the first exposure pattern formed on the first photomask. A gap of about 2 to 10 μm may be provided between the first photosensitive layer and the first photomask 146a.

  Similarly, in the second exposure process, for example, a second photomask is disposed in close contact with the second photosensitive layer, and the second light source disposed opposite to the second photomask is secondly directed toward the second photomask. The second photosensitive layer is exposed by irradiating light. Similar to the first photomask, the second photomask is composed of a glass substrate made of transparent soda glass and a mask pattern (second exposure pattern) formed on the glass substrate. Therefore, the second exposure process exposes a portion of the second photosensitive layer along the second exposure pattern formed on the second photomask. In this case, a gap of about 2 to 10 μm may be provided between the second photosensitive layer and the second photomask.

  In the first exposure process and the second exposure process, the emission timing of the first light from the first light source and the emission timing of the second light from the second light source may be performed simultaneously or differently. At the same time, the first photosensitive layer and the second photosensitive layer can be exposed simultaneously by one exposure process, and the processing time can be shortened. By the way, when both the first photosensitive layer and the second photosensitive layer are not spectrally sensitized, when the photosensitive material is exposed from both sides, the exposure from one side affects the image formation on the other side (back side). Become.

  That is, the first light from the first light source that has reached the first photosensitive layer is scattered by the silver halide grains in the first photosensitive layer, passes through the first transparent substrate 14A as scattered light, and a part thereof. It reaches the second photosensitive layer. Then, the boundary portion between the second photosensitive layer and the first transparent substrate 14A is exposed over a wide range, and a latent image is formed. Therefore, in the second photosensitive layer, exposure with the second light from the second light source and exposure with the first light from the first light source are performed, and the conductive sheet 10 for the touch panel is formed in the subsequent development processing. In this case, in addition to the conductive pattern (second electrode pattern 16B) by the second exposure pattern, a thin conductive layer by the first light from the first light source is formed between the conductive patterns, and the desired pattern (second exposure) Pattern along the pattern) cannot be obtained. The same applies to the first photosensitive layer.

In order to avoid this, as a result of earnest studies, by setting the thickness of the first photosensitive layer and the second photosensitive layer to a specific range, or by specifying the coating silver amount of the first photosensitive layer and the second photosensitive layer, It has been found that the silver halide itself absorbs light and can limit light transmission to the back side. In the present embodiment, the thickness of the first photosensitive layer and the second photosensitive layer can be set to 1 μm or more and 4 μm or less. The upper limit is preferably 2.5 μm. Moreover, the coating silver amount of the 1st photosensitive layer and the 2nd photosensitive layer was prescribed | regulated to 5-20 g / m < ² >.

  In the above-described double-sided exposure method, there is a problem of image defects due to exposure inhibition due to dust or the like adhering to the sheet surface. It is known to apply a conductive material to the sheet as a dust prevention, but metal oxides remain after processing, impairing the transparency of the final product, and conductive polymers are storable. There is a problem. As a result of intensive studies, it was found that the silver halide with a reduced amount of binder provided the necessary conductivity for antistatic, and the silver / binder volume ratio of the first photosensitive layer and the second photosensitive layer was defined. That is, the silver / binder volume ratio of the first photosensitive layer and the second photosensitive layer is 1/1 or more, and preferably 2/1 or more.

  As described above, the first light from the first light source reaching the first photosensitive layer is set and defined by setting the thickness of the first photosensitive layer and the second photosensitive layer, the coating silver amount, and the volume ratio of silver / binder. Does not reach the second photosensitive layer. Similarly, the second light from the second light source that has reached the second photosensitive layer does not reach the first photosensitive layer. As a result, when the conductive sheet 10 for a touch panel is formed in the subsequent development processing, as shown in FIG. 2 (b), the first main surface of the first transparent substrate 14A has the first exposure pattern as the first exposure pattern. Only the electrode pattern 16A is formed, and only the second electrode pattern 16B by the second exposure pattern is formed on the other main surface of the first transparent substrate 14A, and a desired pattern can be obtained.

  Thus, in the manufacturing method using the above-described double-sided batch exposure, it is possible to obtain the first photosensitive layer and the second photosensitive layer that have both conductivity and suitability for double-sided exposure. Further, the same pattern or different patterns can be arbitrarily formed on both surfaces of the first transparent substrate 14A by the exposure process on one first transparent substrate 14A, thereby easily forming the electrodes of the touch panel. In addition, the touch panel can be made thin (low profile).

  Next, in the first conductive sheet 12A and the second conductive sheet 12B according to the present embodiment, a method using a silver halide photographic light-sensitive material that is a particularly preferable aspect will be mainly described.

  The manufacturing method of the first conductive sheet 12A and the second conductive sheet 12B according to the present embodiment includes the following three modes depending on the mode of the photosensitive material and the development process.

  (1) A mode in which a photosensitive silver halide black-and-white photosensitive material not containing physical development nuclei is chemically developed or thermally developed to form a metallic silver portion on the photosensitive material.

  (2) An embodiment in which a photosensitive silver halide black-and-white photosensitive material containing physical development nuclei in a silver halide emulsion layer is dissolved and physically developed to form a metallic silver portion on the photosensitive material.

  (3) A photosensitive silver halide black-and-white photosensitive material containing no physical development nuclei and an image receiving sheet having a non-photosensitive layer containing physical development nuclei are overlapped and developed by diffusion transfer, and the metallic silver portion is non-photosensitive image-receiving sheet. Form formed on top.

  The aspect (1) is an integrated black-and-white development type, and a light-transmitting conductive film such as a light-transmitting conductive film is formed on the photosensitive material. The resulting developed silver is chemically developed silver or heat developed silver, and is highly active in the subsequent plating or physical development process in that it is a filament with a high specific surface.

  In the above aspect (2), the light-transmitting conductive film such as a light-transmitting conductive film is formed on the photosensitive material by dissolving silver halide grains close to the physical development nucleus and depositing on the development nucleus in the exposed portion. A characteristic film is formed. This is also an integrated black-and-white development type. Although the development action is precipitation on the physical development nuclei, it is highly active, but developed silver is a sphere with a small specific surface.

  In the above aspect (3), the silver halide grains are dissolved and diffused in the unexposed area and deposited on the development nuclei on the image receiving sheet, whereby a light transmitting conductive film or the like is formed on the image receiving sheet. A conductive film is formed. This is a so-called separate type in which the image receiving sheet is peeled off from the photosensitive material.

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

  The chemical development, thermal development, dissolution physical development, and diffusion transfer development mentioned here have the same meanings as are commonly used in the industry, and are general textbooks of photographic chemistry such as Shinichi Kikuchi, “Photochemistry” (Kyoritsu Publishing) (Published in 1955), C.I. E. K. It is described in "The Theory of Photographic Processes, 4th ed." Edited by Mees (Mcmillan, 1977). Although this case is an invention related to liquid processing, a technique of applying a thermal development system as another development system can also be referred to. For example, the techniques described in Japanese Patent Application Laid-Open Nos. 2004-184893, 2004-334077, and 2005-010752, and Japanese Patent Application Nos. 2004-244080 and 2004-085655 can be applied. it can.

  Here, the configuration of each layer of the first conductive sheet 12A and the second conductive sheet 12B according to the present embodiment will be described in detail below.

[First Transparent Base 14A, Second Transparent Base 14B]
Examples of the first transparent substrate 14A and the second transparent substrate 14B include a plastic film, a plastic plate, and a glass plate.

  Examples of the raw material for the plastic film and plastic plate include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN); polyethylene (PE), polypropylene (PP), polystyrene, ethylene vinyl acetate (EVA) / cyclo Polyolefins such as olefin polymer (COP) / cycloolefin polymer (COC); vinyl resins; others, polycarbonate (PC), polyamide, polyimide, acrylic resin, triacetyl cellulose (TAC), and the like can be used.

  As the first transparent substrate 14A and the second transparent substrate 14B, PET (melting point: 258 ° C.), PEN (melting point: 269 ° C.), PE (melting point: 135 ° C.), PP (melting point: 163 ° C.), polystyrene (melting point: 230 ° C.), polyvinyl chloride (melting point: 180 ° C.), polyvinylidene chloride (melting point: 212 ° C.), TAC (melting point: 290 ° C.) or the like, preferably a plastic film or plastic plate having a melting point of about 290 ° C. or less, In particular, PET is preferable from the viewpoints of light transmittance and processability. Since the transparent conductive films such as the first conductive sheet 12A and the second conductive sheet 12B used for the conductive sheet 10 for touch panel are required to be transparent, the transparency of the first transparent base 14A and the second transparent base 14B is as follows. High is preferred.

[Silver salt emulsion layer]
The silver salt emulsion layer that becomes the first electrode pattern 16A of the first conductive sheet 12A and the second electrode pattern 16B of the second conductive sheet 12B contains additives such as a solvent and a dye in addition to the silver salt and the binder.

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

Silver coating amount of silver salt emulsion layer (coating amount of silver salt) is preferably from 1 to 30 g / ^{m 2} in terms of silver, more preferably 1 to 25 g / ^{m 2,} more preferably 5 to 20 g / ^{m 2} . By setting the amount of coated silver in the above range, a desired surface resistance can be obtained when the conductive sheet 10 for a touch panel is used.

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

  The content of the binder contained in the silver salt emulsion layer of the present embodiment is not particularly limited, and can be appropriately determined as long as dispersibility and adhesion can be exhibited. The binder content in the silver salt emulsion layer is preferably ¼ or more, more preferably ½ or more in terms of the silver / binder volume ratio. The silver / binder volume ratio is preferably 100/1 or less, and more preferably 50/1 or less. The silver / binder volume ratio is more preferably 1/1 to 4/1. Most preferably, it is 1/1 to 3/1. By setting the silver / binder volume ratio in the silver salt emulsion layer within this range, even when the amount of coated silver is adjusted, variation in resistance value can be suppressed, and a conductive sheet for touch panel having uniform surface resistance can be obtained. . The silver / binder volume ratio is converted from the amount of silver halide / binder amount (weight ratio) of the raw material to the amount of silver / binder amount (weight ratio), and the amount of silver / binder amount (weight ratio) is further converted to the amount of silver. / It can obtain | require by converting into binder amount (volume ratio).

<Solvent>
The solvent used for forming the silver salt emulsion layer 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 silver salt emulsion layer of the present embodiment is in the range of 30 to 90% by mass with respect to the total mass of the silver salt and binder contained in the silver salt emulsion layer, and 50 to 80 It is preferably in the range of mass%.

<Other additives>
The various additives used in the present embodiment are not particularly limited, and known ones can be preferably used.

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

  Next, each step of the manufacturing method of the first conductive sheet 12A and the second conductive sheet 12B will be described.

[exposure]
This embodiment includes the case where the first electrode pattern 16A and the second electrode pattern 16B are applied by a printing method, but the first electrode pattern 16A and the second electrode pattern 16B are formed by exposure and development, etc., except for the printing method. To do. That is, exposure is performed on a photosensitive material having a silver salt-containing layer provided on the first transparent substrate 14A and the second transparent substrate 14B or a photosensitive material coated with a photolithography photopolymer. 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. Furthermore, a light source having a wavelength distribution may be used for exposure, or a light source having a specific wavelength may be used.

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

[Development processing]
In this embodiment, after the emulsion layer is exposed, development processing is further performed. The development processing can be performed by a normal development processing technique used for silver salt photographic film, photographic paper, printing plate-making film, photomask emulsion mask, and the like. The developer is not particularly limited, but 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 process in the present embodiment can include a fixing process performed for the purpose of removing and stabilizing the silver salt in the unexposed part. For the fixing process in the present invention, a fixing process technique used for silver salt photographic film, photographic paper, film for printing plate making, emulsion mask for photomask, and the like can be used.

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

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

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

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

  Although the conductive sheet is obtained through the above steps, the surface resistance of the obtained conductive sheet is 100 ohm / sq. The following is preferable, 0.1-100 ohm / sq. Is preferably in the range of 1 to 10 ohm / sq. It is more preferable that it is in the range. By adjusting the surface resistance within such a range, position detection can be performed even with a large touch panel having an area of 10 cm × 10 cm or more. Further, the conductive sheet after the development treatment may be further subjected to a calendar treatment, and can be adjusted to a desired surface resistance by the calendar treatment.

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

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

[Electrode pattern]
The line width of the fine metal wires of the first electrode pattern 16A and the second electrode pattern 16B of the present embodiment can be selected from 30 μm or less, but preferably 1 μm or more and 9 m or less when used as a touch panel material. More preferably, they are 1 micrometer or more and 7 micrometers or less.

  The line spacing (lattice pitch) is preferably 100 μm to 400 μm, more preferably 200 μm to 300 μm. Further, the thin metal wire may have a portion wider than 200 μm for the purpose of ground connection or the like.

  In the electrode pattern in the present embodiment, the aperture ratio is preferably 85% or more, more preferably 90% or more, and most preferably 95% or more from the viewpoint of visible light transmittance. The aperture ratio is the ratio of the first electrode pattern 16A and the second electrode pattern 16B excluding the thin metal wires to the whole. For example, the aperture ratio of the square lattices 24A and 24B having a line width of 15 μm and a pitch of 300 μm. The aperture ratio is 90%.

[Light transmissive part]
The “light transmissive part” in the present embodiment means a part having translucency other than the first electrode pattern 16A and the second electrode pattern 16B in the first conductive sheet 12A and the second conductive sheet 12B. As described above, the transmittance in the light transmissive portion is the transmission indicated by the minimum value of the transmittance in the wavelength region of 380 to 780 nm excluding contributions of light absorption and reflection of the first transparent substrate 14A and the second transparent substrate 14B. The rate is 90% or more, preferably 95% or more, more preferably 97% or more, even more preferably 98% or more, and most preferably 99% or more.

[First conductive sheet 12A and second conductive sheet 12B]
The thickness of the first transparent substrate 14A and the second transparent substrate 14B in the first conductive sheet 12A and the second conductive sheet 12B according to the present embodiment is preferably 5 to 350 μm, and more preferably 30 to 150 μm. Further preferred. If it is the range of 5-350 micrometers, the transmittance | permeability of a desired visible light will be obtained and handling will also be easy.

  The thickness of the metallic silver portion provided on the first transparent substrate 14A and the second transparent substrate 14B depends on the coating thickness of the silver salt-containing layer coating applied on the first transparent substrate 14A and the second transparent substrate 14B. Can be determined as appropriate. The thickness of the metallic silver portion can be selected from 0.001 mm to 0.2 mm, but is preferably 30 μm or less, more preferably 20 μm or less, and further preferably 0.01 to 9 μm. And most preferably 0.05 to 5 μm. Moreover, it is preferable that a metal silver part is pattern shape. The metallic silver part may be a single layer or a multilayer structure of two or more layers. When the metallic silver portion is patterned and has a multilayer structure of two or more layers, different color sensitivities can be imparted so as to be sensitive to different wavelengths. Thereby, when the exposure wavelength is changed and exposed, a different pattern can be formed in each layer.

  As the thickness of the conductive metal part, the thinner the display panel, the wider the viewing angle of the display panel, and the thinner the display is required for improving the visibility. From such a viewpoint, the thickness of the layer made of the conductive metal carried on the conductive metal part is preferably less than 9 μm, more preferably 0.1 μm or more and less than 5 μm, and more preferably 0.1 μm or more. More preferably, it is less than 3 μm.

  In the present embodiment, the thickness of the layer made of conductive metal particles is formed by controlling the coating thickness of the silver salt-containing layer described above to form a metallic silver portion having a desired thickness, and further by physical development and / or plating treatment. Therefore, even the first conductive sheet 12A and the second conductive sheet 12B having a thickness of less than 5 μm, preferably less than 3 μm can be easily formed.

  In addition, in the manufacturing method of the first conductive sheet 12A and the second conductive sheet 12B according to the present embodiment, steps such as plating are not necessarily performed. In the manufacturing method of the first conductive sheet 12A and the second conductive sheet 12B according to the present embodiment, a desired surface resistance can be obtained by adjusting the coating silver amount of the silver salt emulsion layer and the silver / binder volume ratio. It is. In addition, you may perform a calendar process etc. as needed.

(Hardening after development)
It is preferable to perform a film hardening process by immersing the film in a hardener after the silver salt emulsion layer is developed. Examples of the hardener include dialdehydes such as glutaraldehyde, adipaldehyde, 2,3-dihydroxy-1,4-dioxane, and inorganic compounds such as boric acid and chromium alum / potassium alum. No. 141279 can be mentioned.

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

[Example]
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.

  About the laminated conductive sheets according to Examples 1 to 8, the surface resistance and the transmittance were measured, and the moire and visibility were evaluated. Table 3 shows the breakdown of Examples 1 to 8, the measurement results, and the evaluation results.

<Examples 1-8>
(Silver halide photosensitive material)
An emulsion containing 10.0 g of gelatin per 150 g of Ag in an aqueous medium and containing silver iodobromochloride grains having an average equivalent sphere diameter of 0.1 μm (I = 0.2 mol%, Br = 40 mol%) was prepared. .

  In this emulsion, K3Rh2Br9 and K2IrCl6 were added so as to have a concentration of 10-7 (mol / mol silver), and silver bromide grains were doped with Rh ions and Ir ions. After adding Na2PdCl4 to this emulsion and further performing gold-sulfur sensitization using chloroauric acid and sodium thiosulfate, together with the gelatin hardener, the first transparent substrate was coated so that the coating amount of silver was 10 g / m2. 14A and the second transparent substrate 14B (here, both polyethylene terephthalate (PET)) were applied. At this time, the volume ratio of Ag / gelatin was 2/1.

  Coating was performed for 20 m with a width of 25 cm on a PET support having a width of 30 cm, and both ends were cut off by 3 cm so as to leave a central portion of the coating, thereby obtaining a roll-shaped silver halide photosensitive material.

(exposure)
The exposure pattern is the pattern shown in FIGS. 1 and 3 for the first conductive sheet 12A, and the pattern shown in FIGS. 1 and 4 for the second conductive sheet 12B, and is a first transparent A4 size (210 mm × 297 mm). The test was performed on the substrate 14A and the second transparent substrate 14B. The exposure was performed using parallel light using a high-pressure mercury lamp as a light source through the photomask having the above pattern.

(Development processing)
・ Developer 1L formulation Hydroquinone 20 g
Sodium sulfite 50 g
Potassium carbonate 40 g
Ethylenediamine tetraacetic acid 2 g
Potassium bromide 3 g
Polyethylene glycol 2000 1 g
Potassium hydroxide 4 g
Adjust to pH 10.3-Fixer 1L formulation Ammonium thiosulfate solution (75%) 300 ml
Ammonium sulfite monohydrate 25 g
1,3-diaminopropane tetraacetic acid 8 g
Acetic acid 5 g
Ammonia water (27%) 1 g
Adjusted to pH 6.2 Processed photosensitive material using the above processing agent using Fujifilm's automatic processor FG-710PTS Processing conditions: development 35 ° C. for 30 seconds, fixing 34 ° C. for 23 seconds, washed water (5 L / Min) for 20 seconds.

Example 1
The line widths of the conductive portions (first electrode pattern 16A and second electrode pattern 16B) of the produced first conductive sheet 12A and second conductive sheet 12B are 1 μm, and the length of one side of the grids 24A and 24B is 50 μm.

(Example 2)
The first conductive sheet 12A and the second conductive sheet 12B according to the second embodiment are the same as the first embodiment except that the line width of the conductive portion is 3 μm and the length of one side of the grids 24A and 24B is 100 μm. Was made.

Example 3
The first conductive sheet 12A and the second conductive sheet 12B according to the third embodiment are the same as the first embodiment except that the line width of the conductive portion is 4 μm and the length of one side of the grids 24A and 24B is 150 μm. Was made.

Example 4
The first conductive sheet 12A and the second conductive sheet 12B according to the fourth embodiment are the same as the first embodiment except that the line width of the conductive portion is 5 μm and the length of one side of the lattices 24A and 24B is 210 μm. Was made.

(Example 5)
The first conductive sheet 12A and the second conductive sheet 12B according to the fifth embodiment are the same as the first embodiment except that the line width of the conductive portion is 8 μm and the length of one side of the grids 24A and 24B is 250 μm. Was made.

(Example 6)
The first conductive sheet 12A and the second conductive sheet 12B according to the sixth embodiment are the same as the first embodiment except that the line width of the conductive portion is 9 μm and the length of one side of the grids 24A and 24B is 300 μm. Was made.

(Example 7)
The first conductive sheet 12A and the second conductive sheet 12B according to Example 7 are the same as Example 1 except that the line width of the conductive part is 10 μm and the length of one side of the grids 24A and 24B is 300 μm. Was made.

(Example 8)
The first conductive sheet 12A and the second conductive sheet 12B according to Example 8 are the same as Example 1 except that the line width of the conductive part is 15 μm and the length of one side of the grids 24A and 24B is 400 μm. Was made.

(Surface resistance measurement)
In order to confirm the quality of the detection accuracy, the surface resistivity of the first conductive sheet 12A and the second conductive sheet 12B is arbitrarily determined with a Learstar GP (model number MCP-T610) series four-probe probe (ASP) manufactured by Dia Instruments. It is the average value of the values measured at 10 locations.

(Measurement of transmittance)
In order to confirm transparency, the transmittance of the first conductive sheet 12A and the second conductive sheet 12B was measured using a spectrophotometer.

(Evaluation of moire)
Examples 1-8, the first conductive sheet 12A is laminated on the second conductive sheet 12B to produce a laminated conductive sheet, and then the laminated conductive sheet is pasted on the display screen of the liquid crystal display device to form a touch panel did. Then, a touch panel is installed in a turntable and a liquid crystal display device is driven to display white. In this state, the rotating disk was rotated between a bias angle of −45 ° to + 45 °, and the moire was visually observed and evaluated.

  Moire is evaluated at an observation distance of 1.5 m from the display screen of the liquid crystal display device. A when moire does not appear, B when moire is seen at a level where there is no problem, and moire appear. The case was C.

(Visibility evaluation)
Prior to the evaluation of the above moire, when a touch panel is installed on a turntable and the liquid crystal display device is driven to display white, whether there is any line thickening or black spots, and the first conductive sheet 12A and It was confirmed with the naked eye whether the disconnection part with the 2nd electroconductive sheet 12B was conspicuous.

  On the other hand, among Examples 1 to 8, Examples 1 to 7 were good in conductivity, transmittance, moire, and visibility. In Example 8, the evaluation of moire and the evaluation of visibility are inferior to those of Examples 1 to 7, but the moire is only slightly seen at a problem-free level, and the display image of the display device is difficult to see. It never happened.

  In addition, projection capacitive touch panels were produced using the laminated conductive sheets according to Examples 1 to 8 described above. When touched with a finger, it was found that the response speed was fast and the detection sensitivity was excellent. In addition, when two or more points were touched and operated, good results were obtained in the same manner, and it was confirmed that multi-touch could be supported.

  The conductive sheet and the touch panel for the touch panel according to the present invention are not limited to the above-described embodiments, and can of course have various configurations without departing from the gist of the present invention.

  DESCRIPTION OF SYMBOLS 10 ... Conductive sheet for touchscreens, 12A ... 1st conductive sheet, 12B ... 2nd conductive sheet, 14A ... 1st transparent base | substrate, 14B ... 2nd transparent base | substrate, 16A ... 1st electrode pattern, 16B ... 2nd electrode pattern, 18A ... 1st conductive pattern, 18B ... 2nd conductive pattern, 20A ... 1st non-conductive pattern, 20B ... 2nd non-conductive pattern, 22A ... Disconnection part, 22B ... Disconnection part, 24A ... Grid 24B ... Grid, 70 ... Combination pattern 76 ... Small lattice

Claims (12)

A substrate having a first main surface and a second main surface;
A first electrode pattern disposed on the first main surface;
The first electrode pattern includes a plurality of grids made of a plurality of intersecting thin metal wires, and a plurality of first conductive patterns extending in a first direction and a plurality of first conductive patterns for electrically separating the plurality of first conductive patterns. Alternately provided with non-conductive patterns, the first non-conductive pattern has a first disconnection part in addition to the crossing part of the thin metal wires,
A second electrode pattern disposed on the second main surface;
The second electrode pattern is composed of a plurality of grids made of a plurality of thin metal wires intersecting each other, and a plurality of second conductive patterns extending in a second direction orthogonal to the first direction and the plurality of second conductive patterns are electrically connected. A plurality of second non-conductive patterns that are separated alternately, and the second non-conductive pattern has a second disconnection portion in addition to the intersection of the thin metal wires,
When viewed from above, the plurality of first conductive patterns and the plurality of second conductive patterns are orthogonal to each other, and a small lattice is formed by the lattice of the first electrode pattern and the lattice of the second electrode pattern. A conductive sheet in which the first electrode pattern and the second electrode pattern are disposed on the substrate. A first substrate having a first main surface and a second main surface;
A first electrode pattern disposed on the first main surface of the first substrate;
The first electrode pattern includes a plurality of grids made of a plurality of intersecting thin metal wires, and a plurality of first conductive patterns extending in a first direction and a plurality of first conductive patterns for electrically separating the plurality of first conductive patterns. Alternately provided with non-conductive patterns, the first non-conductive pattern has a first disconnection part in addition to the crossing part of the thin metal wires,
A second substrate having a first main surface and a second main surface;
A second electrode pattern disposed on the first main surface of the second substrate;
The second electrode pattern is composed of a plurality of grids made of a plurality of thin metal wires intersecting each other, and a plurality of second conductive patterns extending in a second direction orthogonal to the first direction and the plurality of second conductive patterns are electrically connected. A plurality of second non-conductive patterns that are separated alternately, and the second non-conductive pattern has a second disconnection portion in addition to the intersection of the thin metal wires,
When viewed from above, the plurality of first conductive patterns and the plurality of second conductive patterns are orthogonal to each other, and a small lattice is formed by the lattice of the first electrode pattern and the lattice of the second electrode pattern. A conductive sheet on which the first base and the second base are disposed.   The first disconnection portion is located near the center of the intersection of the metal thin wires of the first non-conductive pattern, and the second disconnection portion is an intersection of the metal thin wires of the second non-conductive pattern. The conductive sheet according to claim 1, which is located near the center of the intersection.   The conductive sheet according to any one of claims 1 to 3, wherein a width of the first disconnection part and a second disconnection part exceeds a line width of the thin metal wire and is 50 µm or less.   When viewed from above, the fine metal wire of the second conductive pattern is positioned in the first broken portion of the first non-conductive pattern, and the fine metal wire of the first conductive pattern is located in the second broken portion of the second non-conductive pattern. The conductive sheet according to claim 1, wherein the conductive sheet is positioned. The width of the fine metal wire of the first conductive pattern and the fine metal wire of the second conductive pattern is a, and the first disconnected portion of the first non-conductive pattern and the second of the second non-conductive pattern. The conductive sheet according to claim 5 satisfying the following relational expression, where b is the width of the disconnected portion.
ba- ≦ 30 μm The width of the fine metal wire of the first conductive pattern and the fine metal wire of the second conductive pattern is a, and the first disconnected portion of the first non-conductive pattern and the second of the second non-conductive pattern. The conductive sheet according to claim 5 satisfying the following relational expression, where b is the width of the disconnected portion.
(B−a) / a ≦ 6   The misalignment between the center position of the thin metal wire of the first conductive pattern and the center position of the second disconnected portion of the second non-conductive pattern, and the center position of the thin metal wire of the second conductive pattern and the first The conductive sheet according to claim 5, wherein a positional deviation of the non-conductive pattern from the center position of the first disconnected portion has a standard deviation of 10 μm or less.   9. The grid according to claim 1, wherein the grid of the first electrode pattern and the grid of the second electrode pattern have a grid pitch of 250 μm to 900 μm, and the small grid has a grid pitch of 125 μm to 450 μm. The conductive sheet according to Item 1.   10. The conductive sheet according to claim 1, wherein the fine metal wires constituting the first electrode pattern and the fine metal wires constituting the second electrode pattern have a line width of 30 μm or less.   The conductive sheet according to any one of claims 1 to 10, wherein the lattice of the first electrode pattern and the lattice of the second electrode pattern have a rhombus shape.   A capacitive touch panel comprising the conductive sheet according to claim 1.

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