WO2013168698A1 - Conductive film - Google Patents

Abstract

A conductive film (10) is a conductive film that has a conductive portion (14) configured with thin metal wires (16) and apertures (18), wherein the conductive portion (14) has points of intersection (22) by the plurality of the thin metal wires (16), and at portions that are over the thin metal wires (16) and that are other than the points of intersection (22), moiré suppression units (26) (projecting portions) are disposed. It is preferable that the moiré suppression units (26) be randomly disposed.

Description

Conductive film

The present invention relates to a conductive film capable of suppressing the occurrence of moire.

Recently, conductive films used for touch panels have attracted attention as conductive films installed in display devices. 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 being applied to a display for a personal computer.

In such future trends, since conventional electrodes use ITO (Indium Tin Oxide), as the resistance increases and the application size increases, the current transfer speed between the electrodes decreases, and the response speed There is a problem that 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). An example of a method for forming a fine metal wire is Japanese Patent Application Laid-Open No. 2004-221564.

When a conductive film in which a large number of such fine metal wires are arranged is arranged on a display panel of a display device, moire may occur due to interference with the pixel arrangement pattern of the display device. As a method of reducing such moire, conventionally, a moire suppressing portion is formed at the intersection of the lattice (see Japanese Patent Application Laid-Open No. 2008-282924), or a moire is formed on a line connecting the intersection in the opening of the lattice. A method of forming a suppression unit has been proposed (see Japanese Patent Application Laid-Open No. 2008-306177).

For example, as described above, when a thin metal wire is used as an electrode of the touch panel, the thin metal wire is made of an opaque material, and thus transparency and visibility become a problem. When a conductive film using a fine metal wire as an electrode is placed on a display panel of a display device and used, good visibility is required even in the following two modes.

In the first mode, when the display device is turned on / displayed, the fine metal lines are difficult to be seen, the visible light transmittance is high, and the pixel period of the display device (for example, the black matrix pattern of the liquid crystal display) and the conductive pattern It is difficult for noise such as moire caused by optical interference to occur.

The second mode is that when the display device is turned off and the screen is black, and the observation is performed under external light such as fluorescent light, sunlight, LED light, etc., the thin metal wire is difficult to see.

The configuration described in Japanese Patent Application Laid-Open No. 2008-282924 increases the area of the intersection by forming a metal layer at the intersection, which makes the intersection of the lattice more noticeable and disadvantageous in terms of visibility. Become. In the configuration described in Japanese Patent Application Laid-Open No. 2008-306177, a metal layer is formed in the opening, so that the aperture ratio may decrease and transparency may decrease.

The present invention has been made in consideration of such a problem, and even when an electrode such as a touch panel is configured by arranging a large number of grids configured with fine metal wires, it is possible to reduce the occurrence of moire, An object of the present invention is to provide a conductive film in which a fine metal wire is difficult to be visually recognized and high transparency can be secured.

[1] The conductive film according to the present invention is a conductive film having a conductive portion and an opening made of a fine metal wire, and the conductive portion has an intersection of the plurality of fine metal wires, and the fine metal wire An overhanging portion is disposed on a line and at a portion other than the intersection.

As a result, the metal thin wire has a form in which an intersection portion centered on the intersection and a pseudo intersection portion centered on the intersection of the metal thin wire and the overhanging portion are arranged. It becomes irregular and does not converge to a specific spatial frequency. As a result, even when the conductive film is placed on the display panel of the display device, for example, interference with the pixel arrangement pattern does not occur, and the generation of moire can be reduced.

That is, even when a conductive film is installed on a display panel and a conductive portion made of a thin metal wire is used as an electrode such as a touch panel or used as an electromagnetic wave shielding filter, the generation of moire can be reduced. Further, it is difficult for the fine metal wires to be visually recognized, and high transparency can be secured.

[2] In the present invention, the combined shape of the conductive portion and the opening may be a mesh shape.

[3] In this case, the projecting portion is at least one side of the plurality of sides constituting the mesh shape, and at a position that does not overlap the intersection of the mesh shape. It is preferable that they are arranged to cross each other.

[4] Furthermore, the overhanging portion is arranged so as to extend across the one side, and the shape of the overhanging portion is a line segment shape, an elliptical shape, or a rhombus shape having the extending direction as a major axis. It may be a parallelogram shape or a polygonal shape.

[5] Furthermore, the projecting portion may have a line segment shape having the extending direction as a major axis.

[6] In this case, it is preferable that the other side intersecting with the one side and the major axis of the projecting portion are substantially parallel.

[7] And when the width of the one side is Wa, the length of the one side is La, and the length of the extending portion in the extending direction is Lb,
Wa <Lb ≦ La
It is preferable that

[8] In this case, it is preferable that Lb ≧ 2 × Wa and Lb ≦ La / 2.

[9] And, according to the numerical specification, it is preferable that 5 μm ≦ Lb ≦ 100 μm.

[10] When the width of the one side is Wa and the line width of the overhanging portion is Wb,
0.995 × Wa ≦ Wb ≦ 3 × Wa
It is preferable that

[11] Furthermore, when the distance from the intersection of the mesh shape to the center position of the overhang on the one side is Da, and the length of the one side is La,
0.1 × La ≦ Da ≦ 0.9 × La
It is preferable that

[12] The line width of the projecting portion is preferably 30 μm or less. More preferably, it is 10 micrometers or less, More preferably, it is 7 micrometers or less.

[13] The length of the one side is preferably 50 μm or more and 900 μm or less. More preferably, they are 50 micrometers or more and 600 micrometers or less, More preferably, they are 50 micrometers or more and 500 micrometers or less.

[14] Further, it is preferable that the conductive portion has a mesh pattern having a plurality of mesh shapes, and the plurality of protruding portions are randomly arranged with respect to the mesh pattern.

[15] In this case, among the plurality of mesh shapes constituting the mesh pattern, a mesh shape in which the protruding portion is not arranged may be present at random.

[16] Of the plurality of mesh shapes constituting the mesh pattern, the arrangement position of the overhanging portion with respect to one or more mesh shapes in which the overhanging portion is arranged may be random.

[17] Among the one or more mesh shapes in which the overhang portions are arranged, in the mesh shape in which the overhang portions are arranged on a plurality of sides, the arrangement positions of the overhang portions on the plurality of sides are random. May be.

[18] Among the overhang portions arranged on a plurality of sides extending radially from one intersection of the mesh shape, at least one of the overhang portions has a distance from the one intersection to a center position, May be different.

[19] The overhanging portions arranged on the adjacent sides may have different distances from the corresponding intersections.

[20] Further, when the number of the sides is Na, the number of the overhang portions is Nb, and the arrangement ratio of the overhang portions is (Nb / Na) × 100%, the arrangement ratio is 10% or more and 100%. The following is preferable.

[21] The line width of the fine metal wire is preferably 30 μm or less. More preferably, it is 10 micrometers or less, More preferably, it is 7 micrometers or less. The lower limit is 0.1 μm or more.

[22] The aperture ratio is preferably 90% or more.
As described above, according to the conductive film of the present invention, even when an electrode such as a touch panel is configured by arranging a large number of grids configured with thin metal wires, the occurrence of moire can be reduced, It is difficult to visually recognize the fine metal wire, and high transparency can be ensured.

It is a top view which shows an example of the electroconductive film which concerns on this Embodiment. It is sectional drawing which abbreviate | omits and shows a part of electroconductive film. It is a top view which partially enlarges and shows an example of an electroconductive film. 4A to 4E are process diagrams showing an example of a method for manufacturing a conductive film according to the present embodiment. 5A and 5B are process diagrams showing another example of a method for manufacturing a conductive film according to the present embodiment. 6A and 6B are process diagrams showing still another example of the method for manufacturing a conductive film according to the present embodiment. It is process drawing which shows the further another example of the manufacturing method of the electroconductive film which concerns on this Embodiment. It is a top view which shows an example of the electroconductive film which concerns on a 1st modification. It is a top view which shows an example of the electroconductive film which concerns on a 2nd modification. It is a top view which shows an example of the conductive film which concerns on a 3rd modification.

Hereinafter, embodiments of the conductive film according to the present invention 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 2, the conductive film 10 according to the present embodiment includes a transparent base 12 (see FIG. 2) and a conductive portion 14 formed on one main surface of the base 12. Have. The conductive portion 14 has a mesh pattern 20 including a metal fine wire (hereinafter referred to as a metal fine wire 16) and an opening 18. The thin metal wire 16 is made of, for example, gold (Au), silver (Ag), or copper (Cu).

Specifically, as shown in FIG. 1, the conductive portion 14 extends in the first direction (x direction) and is arranged in the second direction (y direction in FIG. 1), and a plurality of first metal fine wires 16 a. And a plurality of second metal wires 16b extending in the second direction and arranged in the first direction, each having a mesh pattern 20 formed. The mesh pattern 20 has a large number of intersections 22 formed by a plurality of first metal fine wires 16a and a plurality of second metal fine wires 16b.

Further, one mesh shape of the mesh pattern 20, that is, a combined shape (hereinafter, referred to as a lattice 24) of one opening 18 and four thin metal wires 16 surrounding the one opening 18 is shown in FIG. A square or a rhombus may be used. In addition, it is good also as polygonal shapes, such as a regular hexagon. Further, the shape of one side of the lattice 24 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.

And in this Embodiment, as shown in FIG. 1, the moire suppression part 26 (overhang | projection part) is arrange | positioned in the part other than the intersection 22 on the metal fine wire 16 (formation). Specifically, the moire suppressing unit 26 is a single side 28 at a position that is at least one side 28 of the plurality of sides 28 constituting the grid 24 and does not overlap the intersection 22 of the grid 24. It is arranged so as to extend across. The shape of the moire suppressing portion 26 is a line segment shape with the extending direction as a major axis in FIG. Of course, an elliptical shape, a rhombus shape, a parallelogram shape, or a polygonal shape whose long axis is the extending direction may be used. The moire suppressing part 26 may be formed of the same metal material as that of the thin metal wire 16 or may be formed of another metal material.

Further, the plurality of moire suppressing units 26 are randomly arranged with respect to the mesh pattern 20. The meaning of “randomly arranged” means at least one of the following (a) to (e).

(A) Among the plurality of lattices 24 constituting the mesh pattern 20, there are randomly lattices 24 in which the moire suppressing portion 26 is not arranged.
(B) Among the plurality of lattices 24 constituting the mesh pattern 20, the arrangement position of the moire suppression unit 26 with respect to one or more lattices 24 in which the moire suppression unit 26 is disposed is random.
(C) Among the one or more lattices 24 in which the moire suppression unit 26 is disposed, the lattice 24 in which the moire suppression unit 26 is disposed on the plurality of sides 28 has the arrangement position of the moire suppression unit 26 on the plurality of sides 28. It is random.
(D) In the case where the moiré suppression unit 26 is arranged on each of a plurality of sides 28 extending radially from one intersection 22 of the grid 24, at least one moiré suppression unit 26 is located between one intersection 22 and the center position. The distance is different from the others.
(E) When the moiré suppression unit 26 is arranged on each of the adjacent sides 28, the distances from the corresponding intersections 22 are different.

As described above, by arranging the line-shaped moire suppressing portion 26 on the metal thin line 16 and in a portion other than the intersection point 22, the mesh pattern 20 has the lattice point 24 with the original intersection point 22 as the center. A cross-shaped crossing portion 30 and a pseudo cross-shaped crossing portion 34 centering on the intersection 32 between the side 28 of the lattice 24 and the moire suppressing portion 26 are arranged. Since the arrangement is random, the arrangement of the intersecting portions 30 and 34 becomes irregular and does not converge to a specific spatial frequency. As a result, even when the conductive film 10 according to the present embodiment is installed on, for example, a display panel of a display device, interference with the pixel arrangement pattern does not occur and generation of moire can be reduced.

That is, even when the conductive film 10 is installed on a display panel and a large number of grids 24 made of fine metal wires 16 are arranged and used as an electrode of a touch panel or the like, or when used as an electromagnetic shielding filter, the occurrence of moiré is reduced. In addition, it is difficult to visually recognize the fine metal wires 16, and high transparency can be ensured.

As shown in FIG. 3, the width of one side 28 of the lattice 24 is Wa, the length of one side 28 (the length between two intersections 22) is La, and the moire suppressing portion 26 extends in the extending direction. When the length is Lb,
Wa <Lb ≦ La
It is preferable that In the numerical specification, it is preferable that 5 μm ≦ Lb ≦ 100 μm.

The lower limit of the length Lb is preferably 2 × Wa or more, more preferably 3 × Wa or more, and more preferably 4 × Wa or more. The upper limit of the length Lb is preferably La or less, more preferably La / 2 or less, more preferably La / 3 or less, and particularly preferably La / 4 or less.

Further, the length of the first overhanging portion 26a to the one opening 18a of the moire suppressing portion 26 (the overhanging length Lb1) and the length of the second overhanging portion 26b to the other opening 18b (the overhanging length Lb2). May be the same or different. In this case, the lower limit of each overhang length Lb1 and Lb2 is preferably Wa or more, more preferably 1.5 × Wa or more, and more preferably 2 × Wa or more. The upper limit of each overhang length Lb1 and Lb2 is preferably La / 2 or less, more preferably La / 4 or less, more preferably La / 6 or less, and particularly preferably La / 8 or less.

If the length Lb in the extending direction of the moire suppressing portion 26 is too short, the pseudo cross-shaped crossing portion 34 cannot be formed, and the effect of reducing the occurrence of moire cannot be obtained. If the length Lb is too long, the aperture ratio decreases and high transparency cannot be ensured. The same applies to the overhang lengths Lb1 and Lb2.

The line width Wb of the moiré suppressing portion 26 is preferably 30 μm or less. More preferably, it is 10 micrometers or less, More preferably, it is 7 micrometers or less. In this case, the relationship between the width Wa of one side 28 of the lattice 24 and the line width Wb of the moire suppressing unit 26 is
0.995 × Wa ≦ Wb ≦ 3.000 × Wa
It is preferable that More preferably,
0.995 × Wa ≦ Wb ≦ 2.500 × Wa
And more preferably
0.995 × Wa ≦ Wb ≦ 1.500 × Wa
It is. Particularly preferably,
Wb = Wa
It is.

If the line width Wb of the moire suppressing portion 26 is too small, it does not substantially become a pseudo cross-shaped crossing portion 34, and the effect of reducing the occurrence of moire cannot be obtained. If the line width Wb is too large, the aperture ratio decreases and high transparency cannot be ensured.

[Correction based on Rule 91 20.08.2013]
In addition, it is preferable that the other side intersecting with one side 28 where the moire suppressing part 26 is arranged and the extending direction (long axis) of the moire suppressing part 26 are substantially parallel. The term “substantially parallel” means that the angle formed by the extending direction of the one side 28 and the extending direction of the moire suppressing portion 26 is θ1, and the extending direction of the one side 28 and the other side described above. When the angle is θ2, 0 ° ≦ | θ1−θ2 | ≦ 5 °. If the shape of the lattice 24 is square or rectangular, it is preferable that the one side 28 described above and the extending direction of the moire suppressing portion 26 are substantially orthogonal. As a result, a pseudo cross-shaped crossing portion 34 can be formed by the moire suppressing portion 26 and one side 28.

Of course, the angle | θa | formed by the extending direction of the side 28 and the extending direction of the first projecting portion 26a, and the extending direction of the side 28 and the extending direction of the second projecting portion 26b. The angle | θb | may be different. In this case, it is preferable that 0 ° ≦ | θa−θ2 | ≦ 5 ° and 0 ° ≦ | θb−θ2 | ≦ 5 °.

Further, when the distance from the intersection 22 of the lattice 24 to the center position of the moire suppressing portion 26 on one side 28 is Da, and the length of one side 28 is La,
0.1 × La ≦ Da ≦ 0.9 × La
It is preferable that

If the distance Da is too small or substantially the same as the length La of one side 28, the moire suppressing portion 26 is disposed close to the intersection 22 of the lattice 24. As a result, the intersection 22 of the lattice 24 is obtained. The line width of the cross-shaped intersecting portion 30 centering on is increased, and it is easy to visually recognize as so-called line thickening. On the contrary, if the range of the distance Da is narrower than the above range, the degree of freedom of random arrangement is reduced. Therefore, it is preferable to set the range of the distance Da to the above range.

Further, when the number of the sides 28 of the mesh pattern 20 is Na, the number of the moire suppressing units 26 is Nb, and the arrangement rate of the moire suppressing units 26 is (Nb / Na) × 100%, the arrangement rate is 10% or more. It is preferable that it is 100% or less. An arrangement rate of 100% indicates that one moire suppressing unit 26 is arranged on each side 28.

If the arrangement ratio is too small, a region of the mesh pattern 20 where the pseudo cross-shaped intersection 34 is not formed becomes wide, and there is a problem that moire becomes conspicuous in the region. If the arrangement ratio is too large, the aperture ratio decreases, and high transparency cannot be ensured. On the other hand, if the arrangement rate range is narrower than the above range, the degree of freedom of random arrangement is reduced. Therefore, it is preferable to set the range of the arrangement ratio within the above range.

Here, the length La of one side 28 of the lattice 24 can be selected from 50 μm to 900 μm. Preferably they are 50 micrometers or more and 600 micrometers or less, More preferably, they are 50 micrometers or more and 500 micrometers or less. Further, the line width Wa of the fine metal wire 16 can be selected from 30 μm or less. Preferably it is 10 micrometers or less, More preferably, it is 7 micrometers or less. The lower limit is 0.1 μm or more. The opening ratio of the conductive film 10 is preferably 90% or more. Thereby, high transparency can be ensured.

Next, some examples of the method for manufacturing the conductive film 10 according to the present embodiment will be described with reference to FIGS. 4A to 7.

First, the silver salt photosensitive layer provided on the substrate 12 is exposed, developed, and fixed to form a metal silver portion or a metal silver portion and a conductive metal carried on the metal silver portion. And a method of forming the moire suppressing portion 26.

Specifically, as shown in FIG. 4A, a silver salt photosensitive layer 40 obtained by mixing silver halide 36 (for example, silver bromide grains, silver chlorobromide grains or silver iodobromide grains) with gelatin 38 is used as a substrate 12. Apply on top. In FIG. 4A to FIG. 4C, the silver halide 36 is expressed as “grains”, but it is exaggerated to help the understanding of the present invention, and the size, concentration, etc. are shown. It is not a thing.

Thereafter, as shown in FIG. 4B, the silver salt photosensitive layer 40 is subjected to exposure necessary for forming the mesh pattern 20. When silver halide 36 receives light energy, it is exposed to light and generates minute silver nuclei called “latent images” that cannot be observed with the naked eye.

Then, in order to amplify the latent image into a visualized image that can be observed with the naked eye, development processing is performed as shown in FIG. 4C. Specifically, the silver salt photosensitive layer 40 on which the latent image is formed is developed with a development processing solution (both alkaline solution and acidic solution, but usually alkaline solution is large). In this development process, silver ions supplied from silver halide grains or a developer are reduced to metallic silver by using a latent image silver nucleus as a catalyst nucleus by a reducing agent called a developing agent in the developer, and as a result The image silver nuclei are amplified to form a visualized silver image (developed silver 42).

After the development processing is completed, silver halide 36 that can be exposed to light remains in the silver salt photosensitive layer 40. In order to remove this, a fixing processing solution (either an acidic solution or an alkaline solution is used as shown in FIG. 4D). However, fixing is usually performed by using an acidic solution.

By performing this fixing process, the metal silver portion 44 is formed in the exposed portion, and only the gelatin 38 remains in the unexposed portion to become the light transmissive portion 46. That is, the mesh pattern 20 and the moire suppressing portion 26 are formed on the base 12 by a combination of the fine metal wires 16 formed by the metal silver portions 44 and the openings 18 formed by the light transmitting portions 46.

The reaction formula of the fixing process when silver bromide is used as the silver halide 36 and the fixing process is performed with thiosulfate is as follows.
AgBr (solid) + 2 S ₂ O ₃ ions → Ag (S ₂ O ₃ ) ₂
(Easily water-soluble complex)
That is, two thiosulfate ions S ₂ O ₃ and silver ions in gelatin 38 (silver ions from AgBr) form a silver thiosulfate complex. Since the silver thiosulfate complex is highly water-soluble, it is eluted from the gelatin 38. As a result, the developed silver 42 is fixed and remains as the metallic silver portion 44.

[Correction based on Rule 91 20.08.2013]
Therefore, the development step is a step of causing the developing agent to react with the latent image to precipitate the developed silver 42, and the fixing step is a step of eluting the silver halide 36 that has not become the developed silver 42 into water. For details, see T.W. H. James, The Theory of the Photographic Process, 4th ed. , Macmillan Publishing Co. , Inc, NY, Chapter 15, pp. 438-442. See 1977.

As shown in FIG. 4E, for example, a plating process (electroless plating or electroplating alone or in combination) is performed, and the conductive metal 48 is supported only on the metallic silver portion 44, thereby the metallic silver portion 44 and the conductive metal. The mesh pattern 20 and the moire suppression part 26 by 48 may be formed.

The mask used for exposure to the silver salt photosensitive layer 40 has a mesh pattern 20 and a mask pattern corresponding to the pattern in which the moire suppressing portion 26 is formed in the opening 18 of the mesh pattern 20. Also good.

Alternatively, the silver salt photosensitive layer 40 may be exposed to a pattern in which the mesh pattern 20 and the moire suppressing portion 26 are formed in the opening 18 of the mesh pattern 20 by digital writing exposure on the silver salt photosensitive layer 40. Good.

As another manufacturing method, as shown in FIG. 5A, for example, a photoresist film 52 on the copper foil 50 formed on the substrate 12 is exposed and developed to form a resist pattern 54, as shown in FIG. 5B. Further, the mesh pattern 20 and the moire suppressing portion 26 may be formed by etching the copper foil 50 exposed from the resist pattern 54. In this case, the mask used in the exposure for the photoresist film 52 may have a mask pattern corresponding to the pattern in which the mesh pattern 20 and the moire suppressing portion 26 are formed.

Alternatively, a pattern in which the mesh pattern 20 and the moire suppressing portion 26 are formed may be exposed on the photoresist film 52 by digital writing exposure on the photoresist film 52.

Also, as shown in FIG. 6A, a paste 56 containing metal fine particles is printed on the substrate 12, and a metal plating 58 is applied to the paste 56 as shown in FIG. 6B, whereby the mesh pattern 20 and the mesh pattern 20 are obtained. A pattern in which the moire suppressing portion 26 is formed in the opening 18 may be formed.

Alternatively, as shown in FIG. 7, a mesh pattern 20 and a pattern in which a moire suppressing portion 26 is formed in the opening 18 of the mesh pattern 20 are printed and formed on the base 12 using a screen printing plate or a gravure printing plate. May be.

Alternatively, although not shown, a photosensitive pre-plated layer is formed on the base 12 using a pretreatment material for plating, and then exposed and developed, and then subjected to a plating treatment, whereby a metal is applied to the exposed and unexposed areas, respectively. The mesh pattern 20 and the moire suppressing portion 26 may be formed by forming a portion and a light transmitting portion. Further, a conductive metal may be supported on the metal part by further performing physical development and / or plating treatment on the metal part.

The following two forms are mentioned as a more preferable form of the method using the plating pretreatment material. The following more specific contents are disclosed in Japanese Patent Application Laid-Open No. 2003-213437, Japanese Patent Application Laid-Open No. 2006-64923, Japanese Patent Application Laid-Open No. 2006-58797, Japanese Patent Application Laid-Open No. 2006-135271, and the like.

(A) A plating layer containing a functional group that interacts with the plating catalyst or its precursor is applied on the substrate 12, and then exposed and developed, and then plated to form a metal part on the material to be plated. Aspect.
(B) After laminating a base layer containing a polymer and a metal oxide and a layer to be plated containing a functional group that interacts with a plating catalyst or a precursor thereof in this order on the substrate 12, and then exposing and developing. A mode in which a metal part is formed on a material to be plated by plating.

Alternatively, the mesh pattern 20 and the moire suppressing portion 26 may be formed on the base 12 by inkjet.

Next, in the conductive film 10 according to the present embodiment, a method using a silver halide photographic light-sensitive material that is a particularly preferable embodiment will be mainly described.

The manufacturing method of the conductive film 10 according to the present embodiment includes the following three forms depending on the photosensitive material and the form of development processing.
(1) A mode in which a photosensitive silver halide black-and-white photosensitive material not containing physical development nuclei is chemically developed or thermally developed to form a metallic silver portion on the photosensitive material.
(2) An embodiment in which a photosensitive silver halide black-and-white photosensitive material containing physical development nuclei in a silver halide emulsion layer is dissolved and physically developed to form a metallic silver portion on the photosensitive material.
(3) A photosensitive silver halide black-and-white photosensitive material containing no physical development nuclei and an image receiving sheet having a non-photosensitive layer containing physical development nuclei are overlapped and developed by diffusion transfer, and the metallic silver portion is non-photosensitive image-receiving sheet. Form formed on top.

The above 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). .

[Correction based on Rule 91 20.08.2013]
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 The 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.

In the above-described example, as shown in FIG. 1, the other side intersecting with one side 28 where the moire suppressing part 26 is arranged and the extending direction (long axis) of the moire suppressing part 26 are substantially parallel. However, the following embodiments can be preferably employed.

That is, as in the conductive film 10a according to the first modification shown in FIG. 8, the extending direction (long axis) of the moire suppressing portion 26 is inclined with respect to one side 28 where the moire suppressing portion 26 is disposed ( May not be orthogonal). Further, like the conductive film 10b according to the second modified example shown in FIG. 9 and the conductive film 10c according to the third modified example shown in FIG. 10, the moire suppressing part 26 having only the first protruding part 26a, and the second protruding part The moire suppressing part 26 having only the part 26b may be arranged at random. FIG. 9 shows an example in which the extending direction (long axis) of the moire suppression unit 26 is orthogonal to one side 28 where the moire suppression unit 26 is arranged, and FIG. On the other hand, an example is shown in which the extending direction (long axis) of the moire suppressing portion 26 is inclined (not orthogonal).

Here, the configuration of each layer of the conductive film 10 according to the present embodiment will be described in detail below.

[Substrate 12]
Examples of the substrate 12 include a plastic film, a plastic plate, and a glass plate.

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

As the substrate 12, PET (melting point: 258 ° C.), PEN (melting point: 269 ° C.), PE (melting point: 135 ° C.), PP (melting point: 163 ° C.), polystyrene (melting point: 230 ° C.), polyvinyl chloride (melting point) : 180 ° C), polyvinylidene chloride (melting point: 212 ° C), TAC (melting point: 290 ° C) or other plastic film or plastic plate having a melting point of about 290 ° C or less is preferable. From the viewpoint of PET, PET is preferable. Since the conductive film 10 used for a touch panel, an electromagnetic shielding film or the like is required to be transparent, it is preferable that the substrate 12 has high transparency.

[Silver salt photosensitive layer 40]
The silver salt photosensitive layer 40 (see FIG. 4A) that becomes the conductive layer (the mesh pattern 20 and the moire suppressing portion 26) of the conductive film 10 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.

Coated silver amount of the silver salt photosensitive layer 40 (coating amount of silver salt) is preferably 1 ~ 30g / m ² in terms of silver, and more preferably ^{1 ~ 25g / m 2, 5} ~ 20g / m 2 and more preferable. By setting the amount of coated silver in the above range, a desired surface resistance can be obtained when the conductive film 10 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 photosensitive layer 40 of the present embodiment is not particularly limited, and can be appropriately determined within a range in which dispersibility and adhesion can be exhibited. The binder content in the silver salt photosensitive layer 40 is preferably ¼ or more, and more preferably ½ or more in terms of a silver / binder volume ratio. The silver / binder volume ratio is preferably 100/1 or less, and more preferably 50/1 or less. The silver / binder volume ratio is more preferably 1/1 to 4/1. Most preferably, it is 1/1 to 3/1. By setting the silver / binder volume ratio in the silver salt photosensitive layer 40 within this range, even when the amount of coated silver is adjusted, variation in the resistance value is suppressed, and the conductive film 10 having a uniform surface resistance can be obtained. it can. 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 photosensitive layer 40 is not particularly limited. For example, water, an organic solvent (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 silver salt photosensitive layer 40 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 photosensitive layer 40, and 50 The range of ˜80 mass% is preferable.

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

[Other layer structure]
A protective layer (not shown) may be provided on the silver salt photosensitive layer 40. In the present embodiment, the “protective layer” means a layer made of a binder such as gelatin or a high molecular polymer. On the silver salt photosensitive layer 40 having photosensitivity in order to exhibit the effect of preventing scratches and improving mechanical properties. 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. Further, for example, an undercoat layer can be provided below the silver salt photosensitive layer 40.

Next, each step of the method for producing the conductive film 10 will be described.

[exposure]
In the present embodiment, the case where the conductive portion 14 is applied by a printing method is included, but the conductive portion 14 is formed by exposure, development, and the like except for the printing method. That is, the photosensitive material having the silver salt photosensitive layer 40 provided on the substrate 12 or a photosensitive material coated with a photopolymer for photolithography is exposed. 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.

[Development processing]
In the present embodiment, after the silver salt photosensitive layer 40 is exposed, further development processing is performed. The development processing can be performed by a normal development processing technique used for silver salt photographic film, photographic paper, printing plate-making film, photomask emulsion mask, and the like. The developer is not particularly limited, but PQ developer, MQ developer, MAA developer and the like can also be used. Commercially available products include, for example, CN-16, CR-56, CP45X, FD prescribed by FUJIFILM Corporation. -3, Papitol, developers such as C-41, E-6, RA-4, D-19, and D-72 prescribed by KODAK, or developers 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 an unexposed portion. For the fixing process in the present invention, a fixing process technique used for silver salt photographic film, photographic paper, film for printing plate making, emulsion mask for photomask, and the like can be used.

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

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 development processing exceeds 4.0, the conductivity of the conductive metal portion (metal thin wire 16) 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.

Through the above steps, the conductive film 10 is obtained, but the surface resistance of the obtained conductive film 10 is 0.1 to 100 ohm / sq. It is preferable that it exists in the range. The lower limit is 1 ohm / sq. 3 ohm / sq. 5 ohm / sq. 10 ohm / sq. The above is preferable. The upper limit is 70 ohm / sq. Hereinafter, 50 ohm / sq. The following is preferable. 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 44 formed by the exposure and development processing, physical development and / or plating treatment for supporting the conductive metal particles on the metal silver portion 44 is performed. You may go. In the present invention, the conductive metal particles may be supported on the metallic silver portion 44 by only one of physical development and plating treatment, or the conductive metal particles are supported on the metallic silver portion 44 by combining physical development and plating treatment. You may let them. In addition, the thing which performed the physical development and / or the plating process to the metal silver part 44 is called a "conductive metal part."

[Correction based on Rule 91 20.08.2013]
“Physical development” in the present embodiment means that metal particles such as silver ions are reduced by a reducing agent on metal or metal compound nuclei to deposit metal particles. This physical development is used for instant B & W film, instant slide film, printing plate production, and the like, and this technique can be used in the present invention.

The physical development may be performed simultaneously with the development processing after exposure or separately after the development processing.

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

[Oxidation treatment]
In the present embodiment, it is preferable to subject the metallic silver portion 44 after development processing 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 slight amount of metal is deposited on the light transmissive portion 46, the metal can be removed and the light transmissive portion 46 can be made almost 100% transparent.

[Conductive metal part]
As described above, the line width of the conductive metal portion (metal thin wire 16) of the present embodiment can be selected from 30 μm or less. When the conductive film 10 is used as an electromagnetic wave shielding film, the line width of the fine metal wire 16 is preferably 1 μm to 20 μm, more preferably 1 μm to 9 μm, further preferably 2 μm to 7 μm, and more preferably 2 μm to 5 μm. Particularly preferred. When the conductive film 10 is used as a conductive sheet for a touch panel, the lower limit is preferably 0.1 μm or more, 1 μm or more, 3 μm or more, 4 μm or more, or 5 μm or more, and the upper limit is 15 μm or less, 10 μm or less, 9 μm or less, 8 μm. Hereinafter, 7 μm or less is preferable. When the line width is less than the above lower limit value, the conductivity becomes insufficient, so that when used for a touch panel, the detection sensitivity becomes insufficient. On the other hand, when the above upper limit is exceeded, moire caused by the conductive metal portion becomes noticeable, or visibility becomes worse when used for a touch panel. In addition, by being in the said range, the moire of an electroconductive metal part is improved and visibility becomes especially good.

The length of one side of the lattice is preferably 50 μm or more and 900 μm or less, more preferably 50 μm or more and 600 μm or less, and more preferably 50 μm or more and 500 μm or less. The conductive metal portion may have a portion whose line width is wider than 200 μm for the purpose of ground connection or the like.

The conductive metal portion in the present embodiment preferably has an aperture ratio of 90% or more from the viewpoint of visible light transmittance. The aperture ratio is a ratio of the light transmissive portion 46 excluding the metal thin wires 16 and the moire suppressing portion 26 to the whole.

[Light transmissive part]
The “light transmissive part” in the present embodiment means a part having a light transmissive property other than the conductive metal part in the conductive film 10. As described above, the transmittance of the light transmissive portion 46 is 90% or more, preferably 90% or more, as indicated by the minimum transmittance in the wavelength region of 380 to 780 nm excluding the contribution of light absorption and reflection of the substrate 12. 95% or more, more preferably 97% or more, even more preferably 98% or more, and most preferably 99% or more.

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

[Conductive film 10]
The thickness of the substrate 12 in the conductive film 10 according to the present embodiment is preferably 75 to 350 μm. If it is in the range of 75 to 350 μm, a desired visible light transmittance can be obtained, and handling is easy. In addition, when two conductive films are laminated to form a conductive sheet for a touch panel, the parasitic capacitance between the conductive films 10 can be reduced.

The thickness of the metallic silver portion 44 provided on the substrate 12 can be appropriately determined according to the coating thickness of the silver salt photosensitive layer coating applied on the substrate 12. The thickness of the metallic silver portion 44 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. Preferably, the thickness is 0.05 to 5 μm. Moreover, it is preferable that the metal silver part 44 is pattern shape. The metallic silver portion 44 may be a single layer or a multilayer structure of two or more layers. When the metallic silver portion 44 has a pattern shape and has a multilayer structure of two or more layers, different color sensitivities can be imparted so that it can be exposed to different wavelengths. Thereby, when the exposure wavelength is changed and exposed, a different pattern can be formed in each layer.

The thickness of the conductive metal part is preferably as the thickness of the touch panel is thinner because the viewing angle of the display panel is wider, and a thin film is also 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, a metal silver portion 44 having a desired thickness is formed by controlling the coating thickness of the above-described silver salt photosensitive layer 40, and further a layer made of conductive metal particles by physical development and / or plating treatment. Therefore, even the conductive film 10 having a thickness of less than 5 μm, preferably less than 3 μm can be easily formed.

In addition, in the method for manufacturing the conductive film 10 according to the present embodiment, it is not always necessary to perform a process such as plating. This is because in the method for manufacturing the conductive film 10 according to the present embodiment, a desired surface resistance can be obtained by adjusting the amount of silver applied to the silver salt photosensitive layer 40 and the silver / binder volume ratio. In addition, you may perform a calendar process etc. as needed.

It is preferable that the silver salt photosensitive layer 40 is developed and then dipped in a hardener to perform the hardening process. Examples of the hardener include dialdehydes such as glutaraldehyde, adipaldehyde, 2,3-dihydroxy-1,4-dioxane, and those described in JP-A-2-141279 such as boric acid. it can.

The conductive film 10 may be provided with a functional layer such as an antireflection layer or a hard coat layer.

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

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

[First embodiment]
In the first example, the visibility, the aperture ratio, and the moire of the conductive film were evaluated by changing the line width of the fine metal wires and the length of one side of the grid in Examples 1 to 11. The breakdown and evaluation results of Examples 1 to 11 are shown in Table 3 described later.

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

In this emulsion, K ₃ Rh ₂ Br ₉ and K ₂ IrCl ₆ 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 Na ₂ PdCl ₄ to this emulsion and further performing gold-sulfur sensitization with chloroauric acid and sodium thiosulfate, together with the gelatin hardener, the coating amount of silver is 10 g / m ^2. It was coated on a transparent substrate (here, both polyethylene terephthalate (PET)). At this time, the volume ratio of Ag / gelatin was 2/1.

Application was carried out on a PET support of 30 cm width with a width of 25 cm for 20 m, and both ends were cut off by 3 cm so as to leave a central part of the application, and a roll-shaped silver halide photosensitive material was obtained.

(exposure)
As shown in FIG. 1, the exposure pattern is a pattern in which moire suppressing portions 26 are randomly arranged on each side 28 of the lattice 24 constituting the mesh pattern 20. The exposure pattern is formed on the A4 size (210 mm × 297 mm) base 12. went. 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
Adjust to pH 6.2

Using the above processing agent, the exposed photosensitive material is processed using an automatic developing machine FG-710PTS manufactured by FUJIFILM Corporation. Development conditions: 35 ° C. for 30 seconds, fixing at 34 ° C. for 23 seconds, washing with running water (5 L / min) for 20 seconds Done in the process.

After performing the exposure and development processes as described above, the line width Wa of the fine metal wires 16 is 10 μm, the length La of one side of the grid 24 (square shape in this example) is 500 μm, and the line width Wb of the moire suppressing unit 26 is A conductive film according to Example 1 having a thickness Lb of 10 μm and a moire suppressing portion 26 of 125.0 μm was produced.

(Example 2)
Example 2 is the same as Example 1 except that the length La of one side of the grating 24 is 400 μm and the length Lb of the moire suppressing portion 26 is 100.0 μm. A film was prepared.

(Example 3)
In the third embodiment, the line width Wa of the fine metal wire 16 is 9 μm, the length La of one side of the grating 24 is 400 μm, the line width Wb of the moire suppression unit 26 is 9 μm, and the length Lb of the moire suppression unit 26 is 100.0 μm. A conductive film according to Example 3 was produced in the same manner as in Example 1 described above except that.

(Examples 4 to 6)
In Examples 4, 5 and 6, the line width Wa of the fine metal wire 16 is 8 μm, 7 μm and 6 μm, the length La of one side of the grating 24 is 300 μm, the line width Wb of the moire suppressing portion 26 is 8 μm, 7 μm and 6 μm, The conductive films according to Examples 4, 5 and 6 were produced in the same manner as in Example 1 except that the length Lb of the moire suppressing portion 26 was 75.0 μm.

(Examples 7 to 9)
In Examples 7, 8 and 9, the line width Wa of the thin metal wire 16 is 5 μm, 4 μm and 3 μm, the length La of one side of the grating 24 is 200 μm, the line width Wb of the moire suppressing part 26 is 5 μm, 4 μm and 3 μm, Conductive films according to Examples 7, 8 and 9 were produced in the same manner as in Example 1 except that the length Lb of the moire suppressing portion 26 was 50.0 μm.

(Example 10)
In Example 10, the line width Wa of the thin metal wire 16 is 2 μm, the length La of one side of the grating 24 is 100 μm, the line width Wb of the moire suppressing unit 26 is 2 μm, and the length Lb of the moire suppressing unit 26 is 25.0 μm. A conductive film according to Example 10 was produced in the same manner as in Example 1 except for the above.

(Example 11)
In Example 11, the line width Wa of the fine metal wire 16 is 1 μm, the length La of one side of the grating 24 is 50 μm, the line width Wb of the moire suppression unit 26 is 1 μm, and the length Lb of the moire suppression unit 26 is 12.5 μm. A conductive film according to Example 11 was produced in the same manner as in Example 1 except for the above.

(Visibility evaluation)
<Difficult to visually recognize fine metal wires>
In Examples 1 to 11, a conductive film was attached to the display panel of the display device to constitute a touch panel. When the touch panel is installed on a turntable and the display device is driven to display white, there are no thick lines or black spots, and whether the touch panel conductive pattern (mesh pattern or moire suppressor) is noticeable Was confirmed with the naked eye.

Then, “◎” indicates that the border of the line thickening or black spot and the conductive pattern is inconspicuous, and “○” indicates that any one of the border of the line thickening, black spot or conductive pattern is conspicuous, “line thick”, black A case where any two of the spots and the boundary of the conductive pattern are conspicuous is indicated by “Δ”, and a case where all of the borders of the thickened black spots and the conductive pattern are conspicuous is indicated by “X”.

(Evaluation of moire)
In each of Examples 1 to 11, after a conductive film is attached to the display panel of the display device, the display device is installed on a rotating disk, and the display device is driven to display white. In this state, the rotating disk was rotated between −20 ° and + 20 ° bias angle, and the moire was visually observed and evaluated.

Moire was evaluated at an observation distance of 0.5 m from the display screen of the display device. When moire was not revealed, ◯, when moire was seen at a slight level with no problem, moiré was revealed. The case was marked with x. And, as an overall score, A when the angle range that becomes ◯ is 10 ° or more, B when the angle range that becomes ◯ is less than 10 °, and there is no angle range that becomes ○, and the angle range that becomes × is less than 30 ° In the case of D, the case where there was no angle range for C and ◯ and the angle range for X was 30 ° or more was defined as D.

From Table 3, Examples 1 to 11 all had good visibility, the aperture ratio was 90% or more, and the moire was evaluated as B or more. In particular, in Examples 2 to 11, the visibility was excellent, the aperture ratio was 90% or more, and the moire was A evaluation.

From this, the line width Wa of the fine metal wire 16 can be selected from 30 μm or less, preferably 10 μm or less, and the length La of one side of the grating 24 can be selected from 50 μm to 900 μm, but 50 μm to 500 μm. Is preferable.

[Second Embodiment]
In the second example, the visibility, the aperture ratio, and the moire when the length Lb of the moire suppressing portion was changed in the above-described example 9 were evaluated.

(Samples 1 to 3)
Samples 1, 2 and 3 were prepared as in Example 9, except that the length Lb of the moire suppression portion 26 was 6 μm, 9 μm and 12 μm. did.

(Sample 4)
For Sample 4, a conductive film was produced in the same manner as in Example 9 described above.

(Samples 5-7)
Samples 5, 6 and 7 were prepared as conductive films according to Samples 5, 6 and 7 in the same manner as in Example 9 except that the length Lb of the moire suppressing portion 26 was set to 67 μm, 100 μm and 200 μm. did.

Table 4 shows the evaluation results for samples 1-7.

From Table 4, Samples 1 to 7 all had good visibility, an aperture ratio of 94% or higher, and a moire evaluation of B or higher. Among them, in the sample 2, the moire was B evaluation, but the visibility was ◎ evaluation. In sample 6, the visibility was evaluated as ○, but the moire was evaluated as A. In particular, Samples 3 to 5 all had a visibility of ◎, an aperture ratio of 97% or higher, and a moire of A evaluation.

From this, the lower limit of the length Lb is preferably 2 × Wa or more, more preferably 3 × Wa or more, more preferably 4 × Wa or more, and the upper limit of the length Lb is La or less. It is preferable that it is La / 2 or less, more preferably La / 3 or less, and particularly preferably La / 4 or less.

[Third embodiment]
In the third example, the visibility, the aperture ratio, and the moire when the line width Wb of the moire suppressing unit 26 is changed in the above-described example 9 were evaluated.

(Samples 8 and 9)
For Samples 8 and 9, conductive films according to Samples 8 and 9 were produced in the same manner as in Example 9 described above except that the line width Wb of the moire suppressing portion 26 was 1.5 μm and 2.7 μm.

(Sample 10)
For Sample 10, a conductive film was produced in the same manner as in Example 9 described above.

(Samples 11-15)
Samples 11, 12, 13, 14, and 15 are the examples described above except that the line width Wb of the moire suppressing portion 26 is 4.5 μm, 6.0 μm, 7.5 μm, 9.0 μm, and 12.0 μm. In the same manner as in Example 9, conductive films according to Samples 11, 12, 13, 14, and 15 were produced.

Table 5 shows the evaluation results of Samples 8-15.

From Table 5, among samples 8 to 15, sample 8 had a C evaluation for moire, and sample 15 had a Δ evaluation for visibility. The other samples 9 to 14 all had good visibility, an aperture ratio of 95% or more, and moire evaluation of B or more. In particular, Samples 9 to 12 all had a visibility of ◎, an aperture ratio of 96% or more, and a moire of A evaluation.

For this reason, the ratio (Wb / Wa) between the line width Wa of the fine metal wire and the line width Wb of the moire suppressing portion 26 is preferably 0.9 or more and 3.0 or less, more preferably 0.9 or more and 2.5 or less. More preferably, it is 0.9 or more and 2.0 or less, and particularly preferably 0.9 or more and 1.5 or less.

Note that the conductive film according to the present invention is not limited to the above-described embodiment, and can of course have various configurations without departing from the gist of the present invention.

Claims (22)

1. In a conductive film (10) having a conductive portion (14) and an opening (18) made of a thin metal wire (16),
   The conductive portion (14) has an intersection (22) by a plurality of the thin metal wires (16),
   A conductive film, characterized in that an overhanging portion (26) is disposed on the metal thin wire (16) and at a portion other than the intersection (22).
2. The conductive film according to claim 1,
   The conductive film is characterized in that a combination shape of the conductive portion (14) and the opening portion (18) is a mesh shape.
3. The conductive film according to claim 2,
   The overhang (26)
   The one side (28) at a position that is at least one side (28) of the plurality of sides (28) constituting the mesh shape and does not overlap the intersection (22) of the mesh shape. An electrically conductive film characterized by being disposed so as to intersect with each other.
4. The conductive film according to claim 3.
   The overhang (26) is arranged to extend across the one side (28),
   The conductive film is characterized in that the shape of the projecting portion (26) is a line segment shape, an elliptical shape, a rhombus shape, a parallelogram shape, or a polygonal shape having the extending direction as a major axis.
5. The conductive film according to claim 4, wherein
   The conductive film is characterized in that the projecting portion (26) has a line segment shape with the extending direction as a major axis.
6. The conductive film according to claim 5, wherein
   The conductive film is characterized in that another side intersecting with the one side (28) and the major axis of the overhanging portion (26) are substantially parallel.
7. The conductive film according to claim 5, wherein
   When the width of the one side (28) is Wa, the length of the one side (28) is La, and the length of the extending portion (26) in the extending direction is Lb,
   Wa <Lb ≦ La
   A conductive film characterized in that
8. The conductive film according to claim 7, wherein
   Lb ≧ 2 × Wa and Lb ≦ La / 2
   A conductive film characterized in that
9. The conductive film according to claim 7, wherein
   5 μm ≦ Lb ≦ 100 μm
   A conductive film characterized in that
10. The conductive film according to claim 5, wherein
    When the width of the one side (28) is Wa and the line width of the protruding portion (26) is Wb,
    0.995 × Wa ≦ Wb ≦ 3 × Wa
    A conductive film characterized in that
11. The conductive film according to claim 3.
    When the distance from the mesh intersection (22) to the center position of the overhanging portion (26) on the one side (28) is Da, and the length of the one side (28) is La,
    0.1 × La ≦ Da ≦ 0.9 × La
    A conductive film characterized in that
12. The conductive film according to claim 5, wherein
    The conductive film according to claim 1, wherein a line width (Wb) of the projecting portion (26) is 30 μm or less.
13. The conductive film according to claim 5, wherein
    The conductive film according to claim 1, wherein the length (La) of the one side (28) is not less than 50 μm and not more than 900 μm.
14. The conductive film according to claim 3.
    The conductive portion (14) has a plurality of mesh patterns (20) having the mesh shape,
    The conductive film, wherein the plurality of overhang portions (26) are randomly arranged with respect to the mesh pattern (20).
15. The conductive film according to claim 14.
    The conductive film characterized in that, among the plurality of mesh shapes constituting the mesh pattern (20), a mesh shape in which the projecting portion (26) is not arranged is present at random.
16. The conductive film according to claim 14.
    Of the plurality of mesh shapes constituting the mesh pattern (20), the arrangement positions of the overhang portions (26) with respect to one or more mesh shapes where the overhang portions (26) are arranged are random. Conductive film.
17. The conductive film according to claim 14.
    Among the one or more mesh shapes in which the overhanging portion (26) is arranged, the mesh shape in which the overhanging portion (26) is arranged on a plurality of sides (28) is the above-described one on the plurality of sides (28). A conductive film characterized in that the position of the overhanging portion (26) is random.
18. The conductive film according to claim 3.
    Of the overhang portions (26) arranged on a plurality of sides (28) extending radially from one intersection point (22) of the mesh shape, at least one of the overhang portions (26) is the one intersection point ( A conductive film characterized in that the distance from 22) to the center position is different from the others.
19. The conductive film according to claim 3.
    The conductive film, wherein the overhang portions (26) arranged on the adjacent sides (28) are different in distance from the corresponding intersection (22).
20. The conductive film according to claim 3.
    When the number of the sides (28) is Na, the number of the overhang portions (26) is Nb, and the arrangement ratio of the overhang portions (26) is (Nb / Na) × 100%,
    The conductive film is characterized in that the arrangement ratio is 10% or more and 100% or less.
21. The conductive film according to claim 1,
    The conductive film according to claim 1, wherein the thin metal wire (16) has a line width of 30 μm or less.
22. The conductive film according to claim 1,
    A conductive film having an opening ratio of 90% or more.

Images