WO2016190224A1 - Blackening plating solution and conductive substrate - Google Patents

Abstract

Provided is a blackening plating solution, which comprises nickel sulfate, zinc sulfate, and sulfamic acid and which has a pH of 4.0 to 6.5.

Description

Blackening plating solution, conductive substrate

The present invention relates to a blackening plating solution and a conductive substrate.

The capacitive touch panel converts information on the position of the adjacent object on the panel surface into an electrical signal by detecting a change in capacitance caused by the object in proximity to the panel surface. Since the conductive substrate used in the capacitive touch panel is disposed on the surface of the display, the material of the conductive layer of the conductive substrate is required to have a low reflectance and be hard to be recognized.

Therefore, as a material of the conductive layer used in the capacitive touch panel, a material having a low reflectance and which is hard to be recognized is used, and a wiring is formed on a transparent substrate or a transparent film.

For example, Patent Document 1 discloses a transparent conductive film including a polymer film and a transparent conductive film comprising a metal oxide provided thereon by a vapor deposition method, as a transparent conductive film comprising a metal oxide The use of indium oxide-tin oxide (ITO) films is disclosed.

By the way, in recent years, the screen size of a display provided with a touch panel has been increased, and correspondingly, the area of a conductive substrate such as a transparent conductive film for a touch panel is also required to be increased. However, since ITO has a high electric resistance value, there is a problem that it can not cope with the increase in the area of the conductive substrate.

Therefore, using a metal such as copper instead of ITO as a material of the conductive layer has been studied. However, since metal has a metallic luster, there is a problem that the visibility of the display is reduced by reflection. For this reason, a conductive substrate subjected to a blackening treatment in which a layer made of a black material is formed by a dry method on the surface of the conductive layer has been studied.

Japanese Patent Application Laid-Open No. 2003-151358

However, in the case of the black material, which has been studied conventionally, the reflection of light on the surface of the conductive layer using a metal such as copper has not been sufficiently suppressed. In addition, it takes time to sufficiently blacken the surface of the conductive layer by the dry method, and the productivity is low.

In view of the problems of the prior art described above, an object of the present invention is to provide a blackening plating solution for forming a blackening layer capable of sufficiently suppressing the reflection of light on the surface of a metal layer.

In one aspect of the present invention to solve the above problems,
Provided is a blackening plating solution containing nickel sulfate, zinc sulfate and amidosulfuric acid and having a pH of 4.0 or more and 6.5 or less.

According to one aspect of the present invention, it is possible to provide a blackening plating solution for forming a blackening layer capable of sufficiently suppressing the reflection of light on the surface of a metal layer.

BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing of the electroconductive substrate which concerns on embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing of the electroconductive substrate which concerns on embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing of the electroconductive substrate which concerns on embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing of the electroconductive substrate which concerns on embodiment of this invention. The top view of the conductive substrate provided with the mesh-like wiring concerning the embodiment of the present invention. FIG. 4 is a cross-sectional view taken along line AA ′ of FIG. 3; FIG. 4 is a cross-sectional view taken along line AA ′ of FIG. 3;

Hereinafter, one embodiment of the blackening plating solution and the conductive substrate of the present invention will be described.
(Blackening plating solution)
The blackening plating solution of the present embodiment can contain nickel sulfate, zinc sulfate and amidosulfuric acid, and can have a pH of 4.0 or more and 6.5 or less.

The inventors of the present invention conducted intensive studies on a method of forming a blackened layer capable of sufficiently suppressing the reflection of light on the surface of the metal layer with high productivity.

Conventionally, since the blackening treatment was performed by the dry method, the productivity was low. Therefore, in order to form the blackened layer with high productivity, the inventors of the present invention studied to form the blackened layer using a wet method. Therefore, a blackening plating solution suitable for forming a blackening layer was examined.

While proceeding with the study of the blackening plating solution, the inventors of the present invention suppress the reflection of light on the surface of the metal layer by forming a layer containing nickel and zinc as the blackening layer. It has been found that the reflectance of the conductive substrate can be suppressed. Therefore, the blackening plating solution is preferably a plating solution capable of forming a layer containing nickel and zinc.

Therefore, the blackening plating solution of the present embodiment can contain nickel sulfate and zinc sulfate. Furthermore, by containing the amidosulfuric acid which functions as a complexing agent, it can suppress that a color nonuniformity arises in the formed blackening layer.

However, when the pH of the blackening plating solution is less than 4.0, the formed blackening layer may not have a color capable of sufficiently suppressing the reflection of light, so the pH is preferably 4.0 or more. In addition, when the pH of the blackening plating solution exceeds 6.5, some components of the components of the blackening plating solution may precipitate, etc., and when the blackening plating solution is used to form a blackening layer, Color unevenness may occur in the blackened layer. Therefore, the pH of the blackening plating solution is preferably 6.5 or less.

The agent used to adjust the pH of the blackening plating solution is not particularly limited, but it is preferable to use an alkali containing no metal component so as not to affect the blackening layer to be formed. For this reason, for example, it is preferable that pH is adjusted with ammonia water. That is, the blackening plating solution can contain ammonia (ammonia water) as a pH adjuster.

As described above, the blackening plating solution of the present embodiment can contain nickel sulfate, zinc sulfate, and amidosulfuric acid, but the content of each component is not particularly limited, and the formation is performed. It can be selected arbitrarily according to the degree of suppression of the reflectance required for the blackening layer to be used.

For example, nickel sulfate is considered to exist as nickel sulfate hexahydrate in the blackening plating solution, but the concentration of nickel sulfate hexahydrate in the blackening plating solution is preferably 30 g / L or more. This is because by setting the concentration of nickel sulfate hexahydrate to 30 g / L or more, sufficient nickel can be supplied to the blackened layer to be formed, and generation of color unevenness and the like in the blackened layer can be suppressed. . The upper limit of the concentration of nickel sulfate hexahydrate in the blackening plating solution is not particularly limited, and can be added, for example, so as to be equal to or less than the saturation concentration of nickel sulfate hexahydrate. In particular, from the viewpoint of suppressing the formation of precipitates and the like in the plating solution before forming the blackening layer using the blackening plating solution, the content is preferably 100 g / L or less.

Also, zinc sulfate is considered to exist as zinc sulfate heptahydrate in the blackening plating solution, but the concentration of zinc sulfate heptahydrate in the blackening plating solution is 1.0 g / L or more and 7.5 g / L or more It is preferable that it is the following. This is more suitable for suppressing the reflection of light formed on the surface of the metal layer, in particular, by setting the concentration of zinc sulfate heptahydrate in the blackening plating solution to 1.0 g / L or more. This is because the light reflectance of the conductive substrate can be particularly suppressed. If the concentration of zinc sulfate heptahydrate is higher than 7.5 g / L, color unevenness may occur in the blackened layer to be formed, and therefore it is preferably 7.5 g / L or less.

The ratio of the content (content weight) of zinc as the metal component to the total content (content weight) of nickel and zinc as the metal component contained in the blackening plating solution is 2% by weight or more and 20% by weight or less Is preferred.

By simultaneously containing nickel and zinc, the blackening layer can be made a color suitable for suppressing light reflection on the surface of the metal layer. And, when the ratio of zinc as the metal component to the total weight of nickel and zinc as the metal component contained in the blackening plating solution is 2% by weight or more, the light reflection on the surface of the metal layer is suppressed. This is because the color can be made particularly suitable for the above, and the reflectance of the conductive substrate can be suppressed.

However, if the proportion of zinc is too high, color unevenness may occur in the formed blackening layer. For this reason, the ratio of zinc as the metal component to the total weight of nickel and zinc as the metal component contained in the blackening plating solution is preferably 20% by weight or less.

The concentration of amidosulfuric acid in the blackening plating solution is not particularly limited, but is preferably 10 g / L or more and 30 g / L or less, for example.

The blackening plating solution of the present embodiment may contain any component other than nickel sulfate, zinc sulfate and amidosulfuric acid. For example, a molybdenum (Mo) compound and / or a tin (Sn) compound can be added as an additive.

The blackening plating solution of the present embodiment described above can be suitably used when forming a blackening layer capable of sufficiently suppressing the reflection of light on the surface of the metal layer of the conductive substrate. In addition, by using the blackening plating solution of the present embodiment, the blackening layer can be formed by a wet method such as electrolytic plating, so that the blackening layer is compared to the blackening layer conventionally formed by dry method. Thus, the blackened layer can be formed with good productivity.
(Conductive substrate)
Next, one structural example of the conductive substrate of the present embodiment will be described.

The conductive substrate of the present embodiment includes a transparent substrate, a metal layer formed on at least one surface of the transparent substrate, and a blackening layer formed using a blackening plating solution on the metal layer. You can have

The conductive substrate in the present embodiment means a substrate having a metal layer and a blackening layer on the surface of a transparent base before patterning a metal layer etc., and a substrate having a metal layer etc. patterned. And a wiring board.

Here, first, each member included in the conductive substrate will be described below.

The transparent substrate is not particularly limited, and a transparent substrate such as a resin substrate (resin film) which transmits visible light or a glass substrate can be preferably used.

As a material of the resin substrate which transmits visible light, for example, resins such as polyamide resin, polyethylene terephthalate resin, polyethylene naphthalate resin, cycloolefin resin, polyimide resin, and polycarbonate resin can be preferably used. In particular, polyamide, PET (polyethylene terephthalate), COP (cycloolefin polymer), PEN (polyethylene naphthalate), polyimide, polycarbonate and the like can be more preferably used as the material of the resin substrate that transmits visible light.

The thickness of the transparent substrate is not particularly limited, and can be arbitrarily selected according to the strength, the capacitance, the light transmittance, etc. required for the conductive substrate. The thickness of the transparent substrate can be, for example, 10 μm or more and 200 μm or less. In particular, when used for touch panel applications, the thickness of the transparent substrate is preferably 20 μm or more and 120 μm or less, and more preferably 20 μm or more and 100 μm or less. When used for touch panel applications, for example, in applications where it is required to reduce the thickness of the entire display, the thickness of the transparent substrate is preferably 20 μm to 50 μm.

The total light transmittance of the transparent substrate is preferably high. For example, the total light transmittance is preferably 30% or more, more preferably 60% or more. When the total light transmittance of the transparent substrate is in the above range, the visibility of the display can be sufficiently ensured, for example, when used for a touch panel application.

The total light transmittance of the transparent substrate can be evaluated by the method defined in JIS K 7361-1.

Next, the metal layer will be described.

The material which comprises a metal layer is not specifically limited, Although the material which has the electrical conductivity according to the application can be selected, For example, the material which comprises a metal layer is Cu, Ni, Mo, Ta, Ti, V, Cr Preferably, it is a copper alloy with at least one or more metals selected from Fe, Mn, Co, W, or a material containing copper. The metal layer can also be a copper layer composed of copper.

The method of forming the metal layer on the transparent substrate is not particularly limited, but in order not to reduce the light transmittance, it is preferable not to dispose an adhesive between the transparent substrate and the metal layer. That is, the metal layer is preferably formed directly on at least one surface of the transparent substrate. When the adhesion layer is disposed between the transparent substrate and the metal layer as described later, the metal layer is preferably formed directly on the upper surface of the adhesion layer.

In order to form a metal layer directly on the upper surface of a transparent substrate or the like, the metal layer preferably has a metal thin film layer. Also, the metal layer may have a metal thin film layer and a metal plating layer.

For example, a metal thin film layer can be formed on a transparent substrate by a dry plating method, and the metal thin film layer can be used as a metal layer. Thus, the metal layer can be formed directly on the transparent substrate without the use of an adhesive. As the dry plating method, for example, a sputtering method, a vapor deposition method, an ion plating method and the like can be preferably used.

Moreover, when making the film thickness of a metal layer thick, a metal thin film layer and a metal plating layer are formed by forming a metal plating layer by the electroplating method which is 1 type of the wet plating method by using a metal thin film layer as a feed layer. It can also be made to have a metal layer. Since the metal layer includes the metal thin film layer and the metal plating layer, the metal layer can be formed directly on the transparent substrate without an adhesive.

The thickness of the metal layer is not particularly limited, and when the metal layer is used as a wire, it can be arbitrarily selected according to the magnitude of the current supplied to the wire, the wire width, and the like.

However, if the metal layer is thick, side etching tends to occur because etching takes time to perform the wiring pattern formation, which may cause problems such as difficulty in forming fine lines. Therefore, the thickness of the metal layer is preferably 5 μm or less, more preferably 3 μm or less.

Further, in particular, from the viewpoint of lowering the resistance value of the conductive substrate and enabling sufficient current supply, for example, the thickness of the metal layer is preferably 50 nm or more, more preferably 60 nm or more, and 150 nm It is more preferable that it is more than.

In addition, when a metal layer has a metal thin film layer and a metal plating layer as mentioned above, it is preferable that the sum total of the thickness of a metal thin film layer and the thickness of a metal plating layer is the said range.

Although the thickness of the metal thin film layer is not particularly limited in any case where the metal layer is constituted of a metal thin film layer or in the case of having a metal thin film layer and a metal plating layer, for example, 50 nm or more and 500 nm It is preferable to set it as the following.

The metal layer can be used as a wiring by patterning, for example, a desired wiring pattern as described later. And since the metal layer can lower the electric resistance value than ITO conventionally used as a transparent conductive film, the electric resistance value of the conductive substrate can be reduced by providing the metal layer.

Next, the blackening layer will be described.

The blackening layer can be formed using the blackening plating solution described above. Therefore, for example, after forming the metal layer, it can be formed on the upper surface of the metal layer by a wet method such as electrolytic plating.

For this reason, the blackening layer can be a layer containing nickel and zinc, more specifically, a wet blackening layer.

The blackening plating solution has already been described, and thus the description thereof is omitted here.

The thickness of the blackening layer is not particularly limited, but is preferably, for example, 30 nm or more, and more preferably 50 nm or more. This is because the reflection of light on the surface of the metal layer can be particularly suppressed by setting the thickness of the blackening layer to 30 nm or more.

The upper limit of the thickness of the blackening layer is not particularly limited, but even if it is thicker than necessary, the time required for film formation and the time required for etching when forming a wiring become longer, and the cost rises Will lead to Therefore, the thickness of the blackening layer is preferably 120 nm or less, and more preferably 90 nm or less.

In addition to the transparent substrate, the metal layer and the blackening layer described above, the conductive substrate can be provided with any layer. For example, an adhesive layer can be provided.

A configuration example of the adhesion layer will be described.

As described above, the metal layer can be formed on the transparent substrate, but when the metal layer is formed directly on the transparent substrate, the adhesion between the transparent substrate and the metal layer may not be sufficient. . For this reason, when a metal layer is directly formed on the upper surface of the transparent substrate, the metal layer may peel off from the transparent substrate during the manufacturing process or during use.

So, in the conductive substrate of this embodiment, in order to improve the adhesiveness of a transparent base material and a metal layer, an adhesion layer can be arranged on a transparent base material.

By arranging the adhesion layer between the transparent base and the metal layer, the adhesion between the transparent base and the metal layer can be enhanced, and peeling of the metal layer from the transparent base can be suppressed.

The adhesion layer can also function as a blackening layer. For this reason, it becomes possible to suppress reflection of light of the metal layer by light from the lower surface side of the metal layer, that is, the transparent substrate side.

The material constituting the adhesion layer is not particularly limited, and the adhesion between the transparent substrate and the metal layer, the required degree of suppression of light reflection on the surface of the metal layer, and the use of a conductive substrate It can be arbitrarily selected according to the degree of stability to the environment (eg, humidity, temperature) to be used.

The adhesion layer preferably contains, for example, at least one metal selected from Ni, Zn, Mo, Ta, Ti, V, Cr, Fe, Co, W, Cu, Sn, and Mn. The adhesion layer can further contain one or more elements selected from carbon, oxygen, hydrogen and nitrogen.

The adhesion layer can include a metal alloy containing at least two or more metals selected from Ni, Zn, Mo, Ta, Ti, V, Cr, Fe, Co, W, Cu, Sn, and Mn. Also in this case, the adhesion layer can further contain one or more elements selected from carbon, oxygen, hydrogen, and nitrogen. At this time, as a metal alloy containing at least two or more metals selected from Ni, Zn, Mo, Ta, Ti, V, Cr, Fe, Co, W, Cu, Sn, and Mn, a Cu-Ti-Fe alloy is used. Alternatively, Cu-Ni-Fe alloy, Ni-Cu alloy, Ni-Zn alloy, Ni-Ti alloy, Ni-W alloy, Ni-Cr alloy, Ni-Cu-Cr alloy can be preferably used.

Although the film-forming method of the adhesion layer is not particularly limited, it is preferable to form a film by dry plating. As the dry plating method, for example, a sputtering method, an ion plating method, a vapor deposition method and the like can be preferably used. In the case where the adhesion layer is formed by a dry method, it is more preferable to use a sputtering method because control of the film thickness is easy. As described above, one or more elements selected from carbon, oxygen, hydrogen and nitrogen can be added to the adhesion layer, and in this case, reactive sputtering can be more preferably used.

When the adhesion layer contains one or more elements selected from carbon, oxygen, hydrogen and nitrogen, the atmosphere for forming the adhesion layer is at least one element selected from carbon, oxygen, hydrogen and nitrogen Can be added to the adhesive layer by adding a gas containing. For example, carbon monoxide gas and / or carbon dioxide gas when carbon is added to the adhesion layer, oxygen gas when oxygen is added, hydrogen gas and / or water when hydrogen is added, When nitrogen is added, nitrogen gas can be added to the atmosphere at the time of performing dry plating.

A gas containing one or more elements selected from carbon, oxygen, hydrogen, and nitrogen is preferably added to an inert gas and used as an atmosphere gas in dry plating. The inert gas is not particularly limited but, for example, argon can be preferably used.

The adhesion between the transparent substrate and the adhesion layer can be enhanced by forming the adhesion layer by dry plating as described above. And since the adhesion layer can contain, for example, a metal as a main component, the adhesion to the metal layer is also high. For this reason, peeling of a metal layer can be suppressed by arrange | positioning an adhesion layer between a transparent base material and a metal layer.

The thickness of the adhesion layer is not particularly limited, but is preferably 3 nm to 50 nm, more preferably 3 nm to 35 nm, and still more preferably 3 nm to 33 nm.

When the adhesion layer is also made to function as a blackening layer, that is, when the reflection of light in the metal layer is suppressed, the thickness of the adhesion layer is preferably 3 nm or more as described above.

The upper limit of the thickness of the adhesion layer is not particularly limited, but even if it is thicker than necessary, the time required for film formation and the time required for etching when forming a wiring become longer, and the cost increases. It will incur. Therefore, as described above, the thickness of the adhesive layer is preferably 50 nm or less, more preferably 35 nm or less, and still more preferably 33 nm or less.

Next, a configuration example of the conductive substrate will be described.

As described above, the conductive substrate of the present embodiment can have a transparent substrate, a metal layer, and a blackening layer. Moreover, layers, such as an adhesion layer, can also be provided arbitrarily.

A specific configuration example will be described below with reference to FIGS. 1A and 1B. FIGS. 1A and 1B show examples of cross-sectional views in a plane parallel to the stacking direction of the transparent base material, the metal layer, and the blackening layer of the conductive substrate of the present embodiment.

The conductive substrate of the present embodiment can have, for example, a structure in which a metal layer and a blackening layer are laminated in this order from the transparent substrate side on at least one surface of the transparent substrate.

Specifically, for example, as in the conductive substrate 10A shown in FIG. 1A, the metal layer 12 and the blackening layer 13 may be sequentially laminated one by one on the one surface 11a side of the transparent substrate 11 it can. Further, as in the case of the conductive substrate 10B shown in FIG. 1B, the metal layers 12A and 12B and the black are respectively provided on the side of the surface 11a of the transparent substrate 11 and the other side (the other surface) 11b. And the barrier layers 13A and 13B can be stacked one by one in that order.

Furthermore, for example, an adhesion layer may be provided as an arbitrary layer. In this case, for example, an adhesion layer, a metal layer, and a blackening layer can be formed in this order on at least one surface of the transparent substrate from the transparent substrate side.

Specifically, for example, as in the case of the conductive substrate 20A shown in FIG. 2A, the adhesion layer 14, the metal layer 12, and the blackening layer 13 are laminated in this order on one surface 11a side of the transparent substrate 11. be able to.

Also in this case, the adhesion layer, the metal layer, and the blackening layer may be laminated on both surfaces of the transparent substrate 11. Specifically, as in the case of the conductive substrate 20B shown in FIG. 2B, the adhesion layers 14A and 14B and the metal layers 12A and 12B are formed on one surface 11a side and the other surface 11b side of the transparent substrate 11, respectively. And the blackening layers 13A and 13B can be stacked in that order.

In FIG. 1B and FIG. 2B, when metal layers, blackening layers, etc. are laminated on both sides of the transparent substrate, the layers laminated on the upper and lower sides of the transparent substrate 11 with the transparent substrate 11 as the symmetry plane become symmetrical. Although the example arrange | positioned as shown was shown, it is not limited to the form which concerns. For example, in FIG. 2B, the configuration on one surface 11a side of the transparent substrate 11 is the same as the configuration of FIG. 1B, in which the metal layer 12A and the blackening layer 13A are laminated in that order without providing the adhesion layer 14A. The layers stacked on the upper and lower sides of the transparent substrate 11 may be asymmetric.

By the way, in the conductive substrate of the present embodiment, by providing the metal layer and the blackening layer on the transparent substrate, it is possible to suppress the reflection of light by the metal layer and to suppress the reflectance of the conductive substrate. Can.

The degree of reflectance of the conductive substrate of the present embodiment is not particularly limited, but for example, in order to enhance the visibility of the display when used as a conductive substrate for a touch panel, one having a low reflectance Is good. For example, the average reflectance of light with a wavelength of 400 nm or more and 700 nm or less is preferably 20% or less, and more preferably 19% or less.

The measurement of reflectance can be performed by irradiating light to the blackened layer of the conductive substrate. Specifically, for example, when the metal layer 12 and the blackening layer 13 are laminated in this order on one surface 11a side of the transparent substrate 11 as shown in FIG. 1A, the blackening layer 13 is irradiated so as to irradiate light. The surface A of the light can be irradiated with light and measured. In the measurement, light having a wavelength of 400 nm or more and 700 nm or less is irradiated to the blackened layer 13 of the conductive substrate at an interval of 1 nm as described above, for example, and the average value of the measured values is the reflectance of the conductive substrate be able to.

The conductive substrate of the present embodiment can be preferably used as a conductive substrate for a touch panel. In this case, the conductive substrate can be configured to have mesh-like wiring.

The conductive substrate provided with the mesh-like wiring can be obtained by etching the metal layer and the blackening layer of the conductive substrate of the present embodiment described above.

For example, a two-layer wiring can be used to form a mesh-like wiring. A specific configuration example is shown in FIG. FIG. 3 is a view of the conductive substrate 30 provided with the mesh-like wiring as viewed from the upper surface side in the stacking direction of the metal layer etc., and the transparent base material and the metal layer are patterned so that the wiring pattern can be easily understood. Layers other than the wirings 31A and 31B formed are omitted.

The conductive substrate 30 shown in FIG. 3 has a transparent base 11, a plurality of wirings 31A parallel to the Y-axis direction in the drawing, and a wiring 31B parallel to the X-axis direction. The wirings 31A and 31B are formed by etching a metal layer, and a blackening layer (not shown) is formed on the upper surface or the lower surface of the wirings 31A and 31B. The blackening layer is etched to the same shape as the wirings 31A and 31B.

The arrangement of the transparent substrate 11 and the wirings 31A and 31B is not particularly limited. The structural example of arrangement | positioning with the transparent base material 11 and wiring is shown to FIG. 4A and FIG. 4B. 4A and 4B correspond to cross-sectional views taken along the line AA 'of FIG.

First, as shown in FIG. 4A, the wirings 31A and 31B may be disposed on the upper and lower surfaces of the transparent substrate 11, respectively. In FIG. 4A, blackened layers 32A and 32B etched in the same shape as the wiring are arranged on the upper surface of the wiring 31A and the lower surface of the wiring 31B.

Moreover, as shown to FIG. 4B, using one set of transparent base materials 11, wiring 31A, 31B is arrange | positioned on the up-and-down side on both sides of one transparent base material 11, and one wiring 31B is a transparent base material. It may be disposed between the eleven. Also in this case, blackened layers 32A and 32B etched in the same shape as the wirings are disposed on the top surfaces of the wirings 31A and 31B. As described above, an adhesion layer may be provided in addition to the metal layer and the blackening layer. For this reason, in any case of FIG. 4A and FIG. 4B, for example, an adhesion layer can be provided between the wiring 31A and / or the wiring 31B and the transparent base material 11. When the adhesion layer is provided, the adhesion layer is also preferably etched to the same shape as the wirings 31A and 31B.

The conductive substrate having the mesh-like wiring shown in FIGS. 3 and 4A is, for example, a conductive substrate provided with metal layers 12A and 12B and blackening layers 13A and 13B on both sides of the transparent substrate 11 as shown in FIG. 1B. Can be formed from a flexible substrate.

The metal layer 12A and the blackening layer 13A on one side 11a of the transparent substrate 11 are parallel to the Y-axis direction in FIG. 1B. The etching is performed such that a plurality of linear patterns are arranged at predetermined intervals along the X-axis direction. The X-axis direction in FIG. 1B means a direction parallel to the width direction of each layer. Also, the Y-axis direction in FIG. 1B means a direction perpendicular to the paper surface in FIG. 1B.

Then, a plurality of linear patterns parallel to the X-axis direction in FIG. 1B are formed along the Y-axis direction at predetermined intervals, with the metal layer 12B on the other surface 11b side of the transparent substrate 11 and the blackening layer 13B. Do the etching to be placed.

By the above operation, the conductive substrate having the mesh-like wiring shown in FIG. 3 and FIG. 4A can be formed. In addition, the etching of both surfaces of the transparent base material 11 can also be performed simultaneously. That is, the etching of the metal layers 12A and 12B and the blackening layers 13A and 13B may be performed simultaneously. Further, in FIG. 4A, a conductive substrate having an adhesive layer patterned in the same shape as the wires 31A and 31B between the wires 31A and 31B and the transparent substrate 11 is the conductive substrate shown in FIG. 2B. It can produce by using and etching similarly.

The conductive substrate having the mesh-like wiring shown in FIG. 3 can also be formed by using two conductive substrates shown in FIG. 1A or FIG. 2A. A case where two conductive substrates shown in FIG. 1A are formed will be described by way of example. For the two conductive substrates shown in FIG. 1A, a plurality of metal layers 12 and a plurality of blackening layers 13 are parallel to the X-axis direction. The etching is performed such that the linear patterns of are arranged at predetermined intervals along the Y-axis direction. Then, by aligning two conductive substrates in a direction such that the linear patterns formed on the conductive substrates by the above etching process intersect with each other, a conductive substrate provided with a mesh-like wiring is obtained. be able to. The surface to be bonded when bonding the two conductive substrates is not particularly limited. For example, the surface A in FIG. 1A in which the metal layer 12 and the like are laminated and the other surface 11b in FIG. 1A in which the metal layer 12 and the like are not laminated are bonded to obtain the structure shown in FIG. It can also be done.

Further, for example, the other surfaces 11b in FIG. 1A where the metal layer 12 and the like of the transparent base material 11 are not laminated may be bonded to each other to have a cross section shown in FIG. 4A.

In FIGS. 4A and 4B, the conductive substrate having the adhesion layer patterned in the same shape as the wires 31A and 31B between the wires 31A and 31B and the transparent base 11 is the conductive shown in FIG. 1A. The conductive substrate shown in FIG. 2A can be used instead of the conductive substrate.

The width of the wires and the distance between the wires in the conductive substrate having the mesh-like wires shown in FIGS. 3, 4A and 4B are not particularly limited, and, for example, according to the amount of current flowing in the wires It can be selected.

Moreover, although the example which formed mesh-like wiring (wiring pattern) combining the wiring of linear shape in FIG. 3, FIG. 4 A and FIG. 4B is shown, it is not limited to the form which concerns, A wiring pattern The wiring which comprises can be made into arbitrary shapes. For example, the shapes of the wires forming the mesh-like wiring pattern may be various shapes such as lines (zigzag straight lines) bent in a jagged manner so as not to generate moire (interference fringes) with the image of the display.

Thus, the conductive substrate having mesh-like wiring composed of two layers of wiring can be preferably used, for example, as a conductive substrate for a projected capacitive touch panel.

According to the conductive substrate of the present embodiment described above, the blackening layer is laminated on the metal layer formed on at least one surface of the transparent substrate. And since a blackening layer is formed using the blackening plating solution as stated above, reflection of the light in the metal layer surface can fully be suppressed, and it can be set as the conductive substrate which suppressed the reflectance. Also, for example, when used for applications such as touch panels, the visibility of the display can be enhanced.

Furthermore, since the blackening layer can be formed by the wet method using the blackening plating solution described above, the conductive substrate can be produced with high productivity as compared with the case where the blackening layer is formed using the conventional dry method. It can be produced.
(Method of manufacturing conductive substrate)
Next, one configuration example of the method of manufacturing the conductive substrate of the present embodiment will be described.

The method for producing a conductive substrate of the present embodiment can have the following steps.
The metal layer formation process of forming a metal layer on the at least one surface of a transparent base material.
Blackening layer formation process which forms a blackening layer using a blackening plating solution on a metal layer.

In addition, as a blackening plating solution, the blackening plating solution whose pH is 4.0 or more and 6.5 or less containing nickel sulfate, zinc sulfate, and amidosulfuric acid as stated above can be used.

The method of manufacturing the conductive substrate of the present embodiment will be specifically described below.

In addition, the above-mentioned conductive substrate can be suitably manufactured by the manufacturing method of the conductive substrate of this embodiment. For this reason, since it can be set as the same structure as the case of the above-mentioned conductive substrate except the point explained below, explanation is omitted in part.

The transparent substrate to be subjected to the metal layer forming step can be prepared in advance. The kind of transparent substrate to be used is not particularly limited, but as described above, a transparent substrate such as a resin substrate (resin film) that transmits visible light, a glass substrate, etc. can be preferably used. The transparent substrate can be cut into any size in advance, if necessary.

The metal layer preferably has a metal thin film layer as described above. The metal layer can also have a metal thin film layer and a metal plating layer. For this reason, a metal layer formation process can have the process of forming a metal thin film layer, for example by the dry plating method. In the metal layer forming step, a step of forming a metal thin film layer by dry plating, a step of forming a metal plating layer by electroplating, which is a kind of wet plating, using the metal thin film as a power feeding layer, May be included.

It does not specifically limit as a dry plating method used at the process of forming a metal thin film layer, For example, a vapor deposition method, sputtering method, or ion plating method etc. can be used. In addition, a vacuum evaporation method can be preferably used as an evaporation method. As the dry plating method used in the step of forming the metal thin film layer, it is more preferable to use the sputtering method because the control of the film thickness is particularly easy.

Next, the process of forming a metal plating layer is demonstrated. The conditions in the step of forming the metal plating layer by the wet plating method, that is, the conditions of the electroplating treatment are not particularly limited, and various conditions in the usual way may be adopted. For example, a metal plating layer can be formed by supplying a base having a metal thin film layer formed in a plating tank containing a metal plating solution and controlling the current density and the conveyance speed of the base.

Next, the blackening layer forming step will be described.

In the blackening layer forming step, the blackening layer can be formed using a blackening plating solution containing nickel sulfate, zinc sulfate and amidosulfuric acid as described above and having a pH of 4.0 or more and 6.5 or less.

The blackened layer can be formed by a wet method. Specifically, for example, using a metal layer as a feed layer, a blackening layer can be formed on the metal layer by electrolytic plating in a plating tank containing the above-described blackening plating solution. By forming the blackening layer by electrolytic plating using the metal layer as the feeding layer as described above, the blackening layer can be formed on the entire surface of the metal layer opposite to the side facing the transparent base.

The description of the blackening plating solution is omitted because it has already been described.

In the method of manufacturing a conductive substrate of the present embodiment, an arbitrary step can be further performed in addition to the above-described steps.

For example, when forming an adhesion layer between a transparent base material and a metal layer, an adhesion layer formation process which forms an adhesion layer on the field which forms a metal layer of a transparent base material can be carried out. When the adhesion layer formation step is carried out, the metal layer formation step can be carried out after the adhesion layer formation step, and in the metal layer formation step, metal is formed on the base on which the adhesion layer is formed on the transparent substrate in this step. A thin film layer can be formed.

In the adhesion layer forming step, the film formation method of the adhesion layer is not particularly limited, but it is preferable to form a film by a dry plating method. As the dry plating method, for example, a sputtering method, an ion plating method, a vapor deposition method and the like can be preferably used. In the case where the adhesion layer is formed by a dry method, it is more preferable to use a sputtering method because control of the film thickness is easy. As described above, one or more elements selected from carbon, oxygen, hydrogen and nitrogen can be added to the adhesion layer, and in this case, reactive sputtering can be more preferably used.

The conductive substrate obtained by the method for producing a conductive substrate of the present embodiment can be used, for example, in various applications such as a touch panel. And when using for various uses, it is preferable that the metal layer contained in the conductive substrate of this embodiment, and a blackening layer are patterned. When the adhesion layer is provided, it is preferable that the adhesion layer is also patterned. The metal layer and the blackening layer, and optionally also the adhesion layer, can be patterned, for example according to the desired wiring pattern, and the metal layer and the blackening layer, optionally also the adhesion layer, are patterned in the same shape It is preferable that the

For this reason, the manufacturing method of the conductive substrate of this embodiment can have a patterning step of patterning a metal layer and a blackening layer. When the adhesion layer is formed, the patterning step can be a step of patterning the adhesion layer, the metal layer, and the blackening layer.

The specific procedure of the patterning step is not particularly limited, and can be performed by any procedure. For example, in the case of the conductive substrate 10A in which the metal layer 12 and the blackening layer 13 are stacked on the transparent substrate 11 as shown in FIG. 1A, first, a mask having a desired pattern is disposed on the surface A on the blackening layer 13. A mask placement step can be performed. Then, an etching step may be performed in which the etchant is supplied to the surface A on the blackening layer 13, ie, the surface on which the mask is disposed.

The etchant used in the etching step is not particularly limited, and can be arbitrarily selected according to the material constituting the layer to be etched. For example, the etching solution can be changed layer by layer, or the metal layer and the blackening layer and, in some cases, the adhesion layer can be simultaneously etched with the same etching solution.

In addition, as shown in FIG. 1B, the patterning process can be carried out to pattern the conductive substrate 10B in which the metal layers 12A and 12B and the blackening layers 13A and 13B are stacked on one surface 11a and the other surface 11b of the transparent substrate 11. . In this case, for example, a mask disposing step of disposing a mask having a desired pattern on the surface A and the surface B on the blackening layers 13A and 13B can be performed. Then, an etching step may be performed in which the etchant is supplied to the surface A and the surface B on the blackened layers 13A and 13B, that is, the surface on which the mask is disposed.

The pattern to be formed in the etching step is not particularly limited, and may have an arbitrary shape. For example, in the case of the conductive substrate 10A shown in FIG. 1A, a pattern is formed so that the metal layer 12 and the blackening layer 13 include a plurality of straight lines or lines bent in zigzag (zigzag straight lines) as described above. Can.

In the case of the conductive substrate 10B shown in FIG. 1B, the metal layer 12A and the metal layer 12B can form a pattern so as to form a mesh-like wiring. In this case, the blackening layer 13A is preferably patterned to have the same shape as the metal layer 12A, and the blackening layer 13B is preferably patterned to have the same shape as the metal layer 12B.

For example, after patterning the metal layer 12 etc. about the above-mentioned conductive substrate 10A at a patterning process, the lamination process which laminates | stacks two or more patterned conductive substrates can also be implemented. When laminating, for example, by laminating so that the patterns of the metal layers of the respective conductive substrates intersect, it is also possible to obtain a laminated conductive substrate provided with a mesh-like wiring.

Although the method of fixing the laminated two or more conductive substrates is not particularly limited, for example, it can be fixed by an adhesive or the like.

The conductive substrate obtained by the method for producing a conductive substrate of the present embodiment described above has a structure in which a blackening layer is laminated on a metal layer formed on at least one surface of a transparent substrate. . And since a blackening layer is formed using the blackening plating solution as stated above, reflection of the light in the metal layer surface can fully be suppressed, and it can be set as the conductive substrate which suppressed the reflectance. Also, for example, when used for applications such as touch panels, the visibility of the display can be enhanced.

Furthermore, since the blackening layer can be formed by the wet method using the blackening plating solution described above, the conductive substrate can be produced with high productivity as compared with the case where the blackening layer is formed using the conventional dry method. It can be produced.

The present invention will be described by way of specific examples and comparative examples, but the present invention is not limited to these examples.
(Evaluation method)
First, an evaluation method of the obtained conductive substrate will be described.
(1) Reflectance Measurement was performed by installing a reflectance measurement unit in an ultraviolet-visible spectrophotometer (manufactured by Shimadzu Corporation, model: UV-2600).

As described later, in each of the experimental examples, a conductive substrate having a structure shown in FIG. 1A was produced. For this reason, the reflectance measurement is performed with light having a wavelength of 400 nm or more and 700 nm or less at an interval of 1 nm with an incident angle of 5 ° and a light receiving angle of 5 ° The specular reflectance was measured by irradiation, and the average value was taken as the reflectance (average reflectance) of the conductive substrate.
(2) Evaluation of the appearance of the blackened layer The appearance of the formed blackened layer is evaluated visually, and it is judged to be good if it has a uniform color without color unevenness, and color unevenness occurs. Was judged to be bad.
(3) Judgment The reflectivity of the conductive substrate was 20% or less, and the conductive substrate was evaluated as excellent in the appearance evaluation of the blackened layer.

It was judged as x for a conductive substrate judged that the reflectance of the conductive substrate exceeded 20% and / or the appearance evaluation of the blackened layer was poor.
(Sample preparation conditions)
In each of the following experimental examples, a conductive substrate was produced under the conditions described below, and evaluated by the above-described evaluation method.
[Experimental Example 1]
In Experimental Example 1, six types of blackening plating solutions of Experimental Examples 1-1 to 1-6 in which the pH of the plating solution is different are prepared, and a conductive substrate is prepared using the blackening plating solution of each experimental example. It produced and evaluated. Experimental Examples 1-2 to 1-5 are Examples, and Experimental Examples 1-1 and 1-6 are Comparative Examples.
(1) Blackening Plating Solution The blackening plating solution prepared in this experimental example will be described.

In the blackening plating solution prepared in this experiment, the concentration of nickel sulfate hexahydrate is 40 g / L, the concentration of zinc sulfate heptahydrate is 5 g / L, and the concentration of amidosulfuric acid is 11 g / L. Each component was mixed. Then, ammonia water was further added to prepare the blackening plating solution of each experimental example so that the pH of each blackening plating solution of Experimental Example 1-1 to Experimental Example 1-6 was the value shown in Table 1. .
(2) Conductive substrate (metal layer forming process)
A metal layer was formed on one side of a transparent substrate made of polyethylene terephthalate resin (PET) having a length of 100 m, a width of 500 mm, and a thickness of 100 μm. The total light transmittance of the transparent substrate made of polyethylene terephthalate resin used as the transparent substrate was evaluated by the method defined in JIS K 7361-1 and found to be 97%.

In the metal layer forming step, a metal thin film layer forming step and a metal plating layer forming step were performed.

First, the metal thin film layer forming step will be described.

In the metal thin film layer forming step, a copper thin film layer was formed as a metal thin film layer on one surface of the transparent base material using the above-mentioned transparent base material as a base material.

In the metal thin film layer forming step, first, the above-mentioned transparent substrate from which water was removed by heating in advance to 60 ° C. was placed in the chamber of the sputtering apparatus.

Next, after evacuating the chamber to 1 × 10 ⁻³ Pa, argon gas was introduced to adjust the pressure in the chamber to 1.3 Pa.

Electric power was supplied to a copper target previously set at the cathode of the sputtering apparatus, and a copper thin film layer was formed to a thickness of 0.2 μm on one surface of the transparent substrate.

Next, in the metal plating layer forming step, a copper plating layer was formed as the metal plating layer. The copper plating layer was formed by electroplating so that the thickness of the copper plating layer was 0.3 μm.

By performing the metal thin film layer forming process and the metal plating layer forming process described above, a copper layer having a thickness of 0.5 μm was formed as a metal layer.

The substrate having a 0.5 μm thick copper layer formed on a transparent substrate prepared in the metal layer forming step was immersed in 20 g / L sulfuric acid for 30 seconds and washed, and the following blackening layer forming step was carried out .
(Blackening layer formation process)
In the blackening layer forming step, a blackening layer was formed on one surface of the metal layer by electrolytic plating using a blackening plating solution prepared in advance for each experimental example. In the blackening layer formation step, the electrolytic plating is performed under the conditions of a temperature of blackening plating solution of 40 ° C., a current density of 0.4 A / dm ² , and a plating time of 50 seconds in any of the experimental examples. A layer was formed.

The film thickness of the formed blackened layer was 70 nm.

The above-mentioned reflectance and appearance evaluation were implemented about the conductive substrate obtained by the above process. The results are shown in Table 1.

From the results shown in Table 1, it is found that the pH of the blackening plating solution is 4.0 to 6.5, and the conductive substrate manufactured using the blackening plating solution of Experimental Example 1-2 to Experimental example 1-5. It could be confirmed that the judgment was 〇. That is, for the conductive substrates produced using the blackening plating solutions of Experimental Examples 1-2 to 1-5, which are the examples, the reflectance is 20% or less, and the blackened layer does not contain color unevenness. It could be confirmed that the color was uniform.

On the other hand, in Experimental Example 1-1 of the comparative example in which the pH of the blackening plating solution is 3.5, the reflectivity of the manufactured conductive substrate is as high as 27%, and the determination is x. It could be confirmed. Moreover, in Experimental Example 1-6 of the comparative example in which the pH of the blackening plating solution is 7, it has been confirmed that color unevenness occurs in the formed blackening layer, and the determination becomes x.
[Experimental Example 2]
In Experimental Example 2, three types of blackening plating solutions of Experimental Example 2-1 to Experimental Example 2-3, which have different concentrations of nickel sulfate hexahydrate in the blackening plating solution, are prepared, and A conductive substrate was produced using a blackening plating solution and evaluated. Experimental Examples 2-1 to 2-3 are all working examples.
(1) Blackening Plating Solution The blackening plating solution prepared in this experimental example will be described.

The blackening plating solution prepared in this experimental example was prepared by mixing nickel sulfate hexahydrate, zinc sulfate heptahydrate and amidosulfuric acid so as to have predetermined concentrations.

The concentration of nickel sulfate hexahydrate in the blackening plating solution of this experimental example was added so as to obtain the values shown in Table 2 for Experimental Example 2-1 to Experimental Example 2-3, respectively.

Zinc sulfate heptahydrate is a metal component relative to the total content of nickel and zinc as a metal component when nickel sulfate hexahydrate is added to a concentration shown in Table 2 in each experimental example. It added so that the metal zinc rate which is a ratio of the content of zinc as it will be 10.0 weight%.

Amidosulfuric acid was added to a concentration of 11 g / L. Then, ammonia water was further added to adjust the pH of the blackening plating solution to 6 to prepare a blackening plating solution of each experimental example.
(2) Conductive Substrate A conductive substrate of each experimental example was produced in the same manner as in experimental example 1 except that the blackening plating solution of each experimental example was used in the blackening layer forming step.

The reflectivity and the appearance of the obtained conductive substrate were evaluated. The results are shown in Table 2.

From the results in Table 2, it can be seen that the conductive substrate prepared using the blackening plating solution of Experimental Example 2-1 to Experimental Example 2-3 having a nickel sulfate hexahydrate concentration in the range of 30 g / L to 50 g / L It could be confirmed that the judgment was 〇. That is, for the conductive substrates manufactured using the blackening plating solutions of Experimental Examples 2-1 to 2-3, which are the examples, the reflectance is 20% or less, and the blackened layer does not contain color unevenness. It could be confirmed that the color was uniform.
[Experimental Example 3]
In Experimental Example 3, seven types of blackening plating solutions of Experimental Example 3-1 to Experimental Example 3-7, which have different concentrations of zinc sulfate heptahydrate in the blackening plating solution, are prepared, and A conductive substrate was produced using a blackening plating solution and evaluated. Experimental Examples 3-1 to 3-7 are all examples.
(1) Blackening Plating Solution The blackening plating solution prepared in this experimental example will be described.

The blackening plating solution prepared in this experimental example was prepared by mixing nickel sulfate hexahydrate, zinc sulfate heptahydrate and amidosulfuric acid so as to have predetermined concentrations.

The concentration of zinc sulfate heptahydrate in the blackening plating solution of this experimental example was added so as to obtain the values shown in Table 3 for Experimental Example 3-1 to Experimental Example 3-7, respectively.

In addition, with respect to nickel sulfate hexahydrate, when zinc sulfate heptahydrate is added to the concentration shown in Table 3 in each experimental example, the total content of nickel and zinc as the metal component is constant. It added so that it might become. Specifically, it was added so as to obtain the concentration shown in Table 3.

Amidosulfuric acid was added to a concentration of 11 g / L. Then, ammonia water was further added to adjust the pH of the blackening plating solution to 6 to prepare a blackening plating solution of each experimental example.

Table 3 also shows the metal zinc ratio of the blackening plating solution prepared in each experimental example.
(2) Conductive Substrate A conductive substrate of each experimental example was produced in the same manner as in experimental example 1 except that the blackening plating solution of each experimental example was used in the blackening layer forming step.

The above-mentioned reflectance and appearance evaluation were implemented about the obtained conductive substrate. The results are shown in Table 3.

From the results of Table 3, it was prepared using the blackening plating solution of Experimental Example 3-1 to Experimental Example 3-7 in which the concentration of zinc sulfate heptahydrate is in the range of 1.0 g / L to 7.5 g / L. It was confirmed that the result of the judgment was 〇 for the conductive substrate. That is, for the conductive substrates manufactured using the blackening plating solutions of Experimental Examples 3-1 to 3-7, which are the examples, the reflectance is 20% or less, and the blackened layer does not contain color unevenness. It could be confirmed that the color was uniform.

Although the blackening plating solution and the conductive substrate have been described above in the embodiment and examples and the like, the present invention is not limited to the above embodiment and the examples and the like. Various changes and modifications are possible within the scope of the present invention as set forth in the claims.

This application claims the priority of Japanese Patent Application No. 2015-105752 filed on May 25, 2015 based on the Japanese Patent Office, and the entire contents of Japanese Patent Application No. 2015-105752 I will use it.

10A, 10B, 20A, 20B, 30 Conductive substrate 11 Transparent substrate 12, 12A, 12B Metal layer 13, 13A, 13B, 32A, 32B blackened layer

Claims (6)

1. A blackening plating solution containing nickel sulfate, zinc sulfate and amidosulfuric acid and having a pH of 4.0 or more and 6.5 or less.
2. The blackening plating solution according to claim 1, wherein the pH is adjusted with ammonia water.
3. Concentration of nickel sulfate hexahydrate is more than 30 g / L,
   The blackening plating solution according to claim 1 or 2, wherein the concentration of zinc sulfate heptahydrate is 1.0 g / L or more and 7.5 g / L or less.
4. Relative to the total content of nickel and zinc as metal components,
   The blackening plating solution according to any one of claims 1 to 3, wherein the proportion of the content of zinc as the metal component is 2% by weight or more and 20% by weight or less.
5. A transparent substrate,
   A metal layer formed on at least one surface of the transparent substrate;
   A conductive substrate comprising: a blackening layer formed using the blackening plating solution according to any one of claims 1 to 4 on the metal layer.
6. The conductive substrate according to claim 5, wherein a thickness of the blackening layer is 30 nm or more and 120 nm or less.

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