JP6528597B2 - Conductive substrate, and method of manufacturing conductive substrate - Google Patents

Description

  The present invention relates to a conductive substrate and a method of manufacturing the conductive substrate.

  Conventionally, a transparent conductive film for a touch panel in which an ITO (indium tin oxide) film is formed as a transparent conductive film on a polymer film has been used. (See Patent Document 1)

  By the way, in recent years, the screen size of a display panel with a touch panel has been increased, and correspondingly, an increase in area of a conductive substrate such as a transparent conductive film for a touch panel is required. 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.

  For this reason, for example, as disclosed in Patent Documents 2 and 3, it has been studied to use a metal foil such as copper which has excellent conductivity in place of the ITO film. However, for example, when copper is used for the wiring layer, since copper has a metallic luster, there is a problem that the visibility of the display is lowered by reflection.

  Then, in order to realize the improvement of both the above-mentioned conductivity and visibility characteristics, a conductive substrate on which a blackening layer composed of a black material is formed together with a wiring layer composed of a metal foil such as copper etc. It is being considered.

Unexamined-Japanese-Patent No. 2003-151358 JP, 2011-018194, A JP, 2013-069261, A

  By the way, a display panel with a touch panel is often used outdoors, such as a vending machine or a guidance display board.

  However, the conventional blackened layer, which has been studied for use in a conductive substrate, is not sufficiently resistant to the environment, and has problems such as causing discoloration in long-term use and reducing the effect of improving the visibility. Particularly in the case of a conductive substrate for a touch panel on which a blackening layer is formed on the surface, the influence of the discoloration of the blackening layer is large, and a conductive substrate provided with a blackening layer excellent in environmental resistance has been desired.

  SUMMARY OF THE INVENTION In view of the various problems of the above-mentioned prior art, it is an object of the present invention to provide a conductive substrate provided with a blackened layer excellent in environmental resistance.

In one aspect of the present invention to solve the above problems,
A transparent substrate,
A copper layer disposed on at least one surface side of the transparent substrate;
And a blackening layer disposed on at least one surface side of the transparent substrate and containing oxygen, copper, nickel and molybdenum.
The blackened layer contains 43 atomic percent or more and 60 atomic percent or less of the oxygen,
When the total content of copper, nickel and molybdenum in the blackened layer is 100 atomic%, the content of the molybdenum in the blackened layer is 5 atomic% or more and 40 atomic% or less,
The content of the copper in the blackened layer is 30 atomic% or more and 70 atomic% or less,
The conductive substrate is provided , wherein the content of the nickel in the blackening layer is 15 atomic% or more and 65 atomic% or less .

  According to one aspect of the present invention, it is possible to provide a conductive substrate provided with a blackening layer excellent in environmental resistance.

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. Sectional drawing in the AA 'line of FIG.

Hereinafter, an embodiment of a conductive substrate of the present invention and a method of manufacturing the conductive substrate will be described.
(Conductive substrate)
The conductive substrate of the present embodiment is a transparent substrate,
A copper layer disposed on at least one surface side of the transparent substrate,
And a blackened layer (hereinafter, also simply described as a "blackened layer") disposed on at least one surface side of the transparent substrate and containing oxygen, copper, nickel and molybdenum. .
The blackened layer contains oxygen in the range of 43 atomic percent to 60 atomic percent, and the total content of copper, nickel, and molybdenum in the blackened layer is 100 atomic percent. The content of molybdenum is preferably 5 atomic% or more.

  The conductive substrate in the present embodiment means a substrate having a copper layer or a blackening layer on the surface of a transparent base before patterning a copper layer or the like, and a wiring shape by patterning a copper layer or a blackening layer. And the wiring substrate.

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

  The transparent substrate is not particularly limited, and an insulator film that transmits visible light, a glass substrate, and the like can be preferably used.

  As an insulator film which transmits visible light, resin films, such as a polyamide system film, a polyethylene terephthalate system film, a polyethylene naphthalate system film, a cycloolefin system film, a polycarbonate system film etc. can be used preferably, for example.

  In particular, PET (polyethylene terephthalate), PEN (polyethylene naphthalate), COP (cycloolefin polymer), polyamide, polycarbonate and the like can be more preferably used as the material of the insulator film transmitting 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.

  In addition, for the transparent substrate, the copper layer or the like of the transparent substrate is formed from the viewpoint of enhancing the adhesion with the copper layer or the blackening layer and preventing the copper layer or the like formed on the transparent substrate from peeling off. It is preferable to perform easy adhesion processing such as disposing an easy adhesion layer on the surface.

  The method of easy adhesion treatment is not particularly limited, and any treatment that can enhance the adhesion to a copper layer or the like is sufficient.

  Specifically, for example, there is a method of making the surface of the transparent substrate hydrophilic by applying a p-methyl methacrylate or the like to the surface of the transparent substrate on which the copper layer and the like are to be formed to form an easy adhesion layer. . In addition, as another method of easy adhesion treatment, a method of performing atmospheric pressure plasma treatment on the surface of the transparent substrate on which a copper layer or the like is to be formed, or irradiating Ar ion on a surface of the transparent substrate on which the copper layer or the like is to be formed Methods etc.

  For example, when the wettability of the surface of the PET (polyethylene terephthalate) substrate not subjected to the easy adhesion treatment is evaluated by the wet tension test method, it is usually about 31 mN / m. For this reason, the adhesiveness to a copper layer etc. may not be enough.

  On the other hand, for example, Ar ion is irradiated by sputtering for 5 to 15 minutes on the surface of the PET substrate to perform easy adhesion treatment, whereby the wetting tension of the surface of the PET substrate is 35 mN / m or more, for example 40 mN. It can be improved to about / m to 55 mN / m. For this reason, adhesiveness with a copper layer etc. can be improved especially, and it is preferable.

  When the easy adhesion treatment is performed on the transparent substrate, the degree of the easy adhesion treatment is not particularly limited. However, from the viewpoint of sufficiently enhancing the adhesion to the copper layer etc., the transparent substrate preferably has a wet tension of 35 mN / m or more, for example, 40 mN on the side of the transparent substrate on which the copper layer is disposed. It is more preferable that it is / m or more.

  The wettability of the transparent substrate can be evaluated by the wet tension test method (JIS K6768 (1999)). In addition, the surface on the side on which the copper layer of the above-mentioned transparent substrate is disposed is not only the surface on which the copper layer is directly formed on the transparent substrate, but also the copper layer via the blackening layer on the transparent substrate Can include the formed surface.

  The easy adhesion treatment is not limited to the surface on which the copper layer of the transparent base material is disposed, but may be performed on the surface on which the copper layer is not disposed. However, it is preferable from the viewpoint of productivity and the like to carry out the easy adhesion treatment only on the side on which the copper layer is required to increase the adhesion to the copper layer or the like.

  Next, the copper layer will be described.

  The copper layer is also not particularly limited, but in the case of arranging a blackening layer between the copper layer and the transparent substrate or between the transparent substrate and the copper layer, in order to not reduce the light transmittance. It is preferred not to place an adhesive between the copper layer and the blackening layer. That is, the copper layer is preferably formed directly on the top surface of the other member.

  In order to form a copper layer directly on top of other members, the copper layer preferably has a copper thin film layer. Also, the copper layer may have a copper thin film layer and a copper plating layer.

  For example, a copper thin film layer can be formed on a transparent substrate or a blackening layer by a dry plating method, and the copper thin film layer can be used as a copper layer. Thus, the copper layer can be formed directly on the transparent substrate or the blackening layer without the use of an adhesive.

  When the film thickness of the copper layer is large, the copper thin film layer is used as a feeding layer to form a copper plating layer by a wet plating method to form a copper layer having a copper thin film layer and a copper plating layer. You can also. By having the copper thin film layer and the copper plating layer, the copper layer can be formed directly on the transparent substrate or the blackening layer without using an adhesive.

  The thickness of the copper layer is not particularly limited, and when the copper 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. In particular, the thickness of the copper layer is preferably 100 nm or more, and more preferably 150 nm or more so that a sufficient current can be supplied. Although the upper limit of the thickness of the copper layer is not particularly limited, when the copper layer is thick, side etching occurs because etching takes time to perform the etching to form the wiring, and the resist is peeled off in the middle of the etching And the like. Therefore, the thickness of the copper layer is preferably 3 μm or less, more preferably 700 nm or less.

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

  Next, the blackened layer containing oxygen, copper, nickel and molybdenum will be described.

  Since the copper layer has metallic luster, the copper reflects light as described above only by forming a wiring in which the copper layer is etched on the transparent substrate, and, for example, when used as a conductive substrate for a touch panel, There was a problem that visibility decreased. Therefore, methods of providing a blackening layer have been studied.

  However, as described above, the display panel with the touch panel is often used outdoors, such as a vending machine or a guide display board. Further, the conventional blackened layer which has been studied for use in a conductive substrate is not sufficiently resistant to the environment, and has a problem such as causing discoloration in long-term use and reducing the effect of improving the visibility. In particular, in the case of a conductive substrate for a touch panel on which a blackening layer is formed on the surface, the influence of the discoloration of the blackening layer is large, and a blackening layer excellent in environmental resistance has been desired.

  The term "environmental resistance" as used herein means that there is no significant change in the color of the blackened layer even when placed in a high temperature, high humidity environment, and that light reflection on the surface of the copper layer can be suppressed. doing.

  Therefore, when the inventors of the present invention conducted investigations, the layer containing oxygen, copper, nickel and molybdenum is black and therefore can be used as a blackening layer, and the content of oxygen and molybdenum is within a predetermined range. Found that high environmental resistance can be exhibited, and the present invention was completed.

  The film formation method of the blackening layer is not particularly limited, and the film formation can be performed by any method. However, it is preferable to form a film by a sputtering method because the blackened layer can be formed relatively easily.

  The blackening layer may be, for example, a chamber using a mixed sintered target of copper, nickel and molybdenum (hereinafter also described as a “target of copper-nickel-molybdenum mixed sintering”), or a melted alloy target of copper-nickel-molybdenum A film can be formed by sputtering while supplying oxygen to the inside.

  When using a copper-nickel-molybdenum mixed sintered target or a copper-nickel-molybdenum melted target as a target for forming the blackened layer, these targets alone are used to form a blackened layer. It can be membrane.

  In addition, when using a copper-nickel-molybdenum mixed sintering target or a copper-nickel-molybdenum melted target as a target for forming the blackened layer, for example, a binary co-sputtering method in combination with other targets The blackening layer may be formed by Specifically, for example, a combination of a copper-nickel-molybdenum mixed sintering target or a copper-nickel-molybdenum melted alloy target and a target containing one or more components selected from copper, nickel and molybdenum are combined. Can also be used.

  In addition, the blackening layer uses, for example, a copper-nickel alloy target and a molybdenum target, or uses a copper target and a nickel-molybdenum alloy target, and supplies oxygen into the chamber by a dual co-sputtering method. It is also possible to form a film.

  One structural example of the manufacturing method of the target of copper- nickel- molybdenum mixed sintering is explained. Since copper and molybdenum are difficult to melt and do not form a solid solution, the molybdenum / nickel ratio is set to 25/75 or less so that nickel and molybdenum can form a solid solution when they are produced by a melting method. When the molybdenum / nickel ratio is 25/75 or less, when the total mass of molybdenum and nickel is 100, it means that the mass ratio of molybdenum is 25 or less.

  For this reason, when the molybdenum / nickel ratio exceeds 25/75, it is preferable to prepare and use a copper-nickel-molybdenum mixed sintering target.

  As a method for producing a target of copper-nickel-molybdenum mixed sintering, it is preferable to first prepare a sintered body from a mixed powder of copper, nickel and molybdenum by hot pressing or hot isostatic pressing (HIP) . Then, after processing the obtained sintered body into a predetermined shape, it can be attached to a backing plate to make a target of copper-nickel-molybdenum mixed sintering.

  The sintering temperature at the time of producing a sintered body from the mixed powder of copper, nickel and molybdenum is preferably 850 ° C. or more and 1083 ° C. or less, more preferably 950 ° C. or more and 1050 ° C.

  This is because sintering does not proceed sufficiently at temperatures lower than 850 ° C., and the density of the sintered body is low, and there is a problem that cooling water may remain in pores of the sintered body in planar processing to be a target . If the temperature exceeds 1083 ° C., the melting point of copper is exceeded, which is not preferable because copper flows out.

  In addition, the manufacturing method of the target of copper-nickel-molybdenum mixed sintering is not limited to the said manufacturing method, It will be especially limited if it is a method which can be manufactured so that it may become a target which has desired composition. It can be used.

  The content ratio of oxygen in the gas supplied into the chamber at the time of sputtering is not particularly limited. The amount of oxygen taken into the blackening layer depends on the growth rate (deposition rate) of the blackening layer, and the content of oxygen in the gas supplied into the chamber affects the growth rate of the blackening layer. For this reason, it is preferable to arbitrarily select the content ratio of oxygen in the gas supplied into the chamber at the time of sputtering according to the composition of the target blackening layer and the growth rate of the blackening layer.

  The growth rate of the blackening layer is not particularly limited, but is preferably about 4 nm / min to 20 nm / min, for example, in consideration of productivity and the like.

  Then, in order to form a blackened layer at such a growth rate and to form a blackened layer containing a desired amount of oxygen, a gas containing 25% by volume to 55% by volume of oxygen is supplied to the chamber. However, it is preferable to carry out the film formation of the blackened layer. The content of oxygen in the gas supplied to the chamber is more preferably 30% by volume or more and 45% by volume or less.

  The oxygen partial pressure in the chamber at the time of forming the blackening layer is preferably 0.1 Pa or more, more preferably 0.15 Pa or more.

  As described above, by setting the content ratio of oxygen in the gas supplied into the chamber to 25% by volume or more, the blackened layer can be sufficiently oxidized, and discoloration of the blackened layer due to oxygen and moisture in the air can be achieved. It is preferable because it can be prevented and the environmental resistance can be enhanced. The content of oxygen in the gas supplied into the chamber is more preferably 30% by volume or more.

  However, if the content ratio of oxygen in the gas supplied into the chamber exceeds 55% by volume, the growth rate of the blackened layer becomes slow, which is not preferable. Therefore, as described above, the content of oxygen in the gas supplied into the chamber is preferably 55% by volume or less. In particular, the content of oxygen in the gas supplied into the chamber is preferably 45% by volume or less from the viewpoint of maintaining the growth rate of the blackened layer high and increasing the productivity.

  Note that when sputtering is performed, the gas supplied into the chamber is preferably an inert gas for the remainder other than oxygen. For the remainder other than oxygen, for example, one or more gases selected from argon, xenon, neon and helium can be supplied.

  The composition of the target used in sputtering is not particularly limited, and can be arbitrarily selected in accordance with the composition of the blackened layer to be formed. Note that the easiness of elements from the target during sputtering varies depending on the type of element. For this reason, the composition of the target can be selected according to the composition of the target blackened layer and the easiness of the elements in the target.

  As a target used when performing sputtering, the target of copper-nickel- molybdenum mixed sintering can be used as mentioned above, for example. In this case, although the composition of the target is not particularly limited as described above, the target of the copper-nickel-molybdenum mixed sintering preferably contains molybdenum in a ratio of 5 atomic% to 75 atomic%, and 7 atomic% It is more preferable to contain by the ratio of 65 atomic% or less. 10 atomic% or more and 50 atomic% or less of nickel is preferable. In these cases, the balance can be made of copper.

  As described above, oxygen, copper, nickel, and molybdenum can be contained in the deposited blackened layer. The content ratio of each component in the blackened layer is not particularly limited, but the total content of copper, nickel and molybdenum in the blackened layer, ie, the total content of the metal elements contained in the blackened layer is 100 atoms. In the case of%, the content of molybdenum is preferably 5 atomic% or more. That is, the content ratio of molybdenum in the metal element contained in the blackened layer is preferably 5 atomic% or more.

  This is because the reflectance of light on the surface of the blackened layer can be particularly reduced by setting the content ratio of molybdenum in the metal element contained in the blackened layer to 5 atomic% or more. Also, by setting the content of molybdenum in the metal element contained in the blackened layer to 5 atomic% or more, the amount of oxygen taken into the blackened layer can be increased, and the environmental resistance can be improved. become.

  However, if the content ratio of molybdenum in the metal element contained in the blackening layer is too large, the reactivity of the blackening layer to the etching solution becomes low, which may make it difficult to form a desired wiring pattern. . Therefore, when the total content of copper, nickel, and molybdenum in the blackened layer is 100 atomic percent, the content of molybdenum in the blackened layer, that is, the molybdenum in the metal element contained in the blackened layer The content ratio is preferably 40 atomic% or less.

  When the total content of copper, nickel and molybdenum in the blackened layer, ie, the total content of metal elements contained in the blackened layer is 100 atomic%, the content of copper in the blackened layer 30 atomic% or more and 70 atomic% or less is preferable. That is, the content ratio of copper in the metal element contained in the blackened layer is preferably 30 atomic% or more and 70 atomic% or less. As for the content rate of copper in the metallic element contained in a blackening layer, 40 atomic% or more and 60 atomic% or less are more preferable.

  This is because if the content of copper in the metal element contained in the blackened layer is less than 30 atomic%, the etching property may be deteriorated. Moreover, it is because environmental resistance may fall, when the content rate of copper in the metal element contained in a blackening layer exceeds 70 atomic%.

  Furthermore, when the total content of copper, nickel and molybdenum in the blackened layer, that is, the total content of metal elements contained in the blackened layer is 100 atomic%, the content of nickel in the blackened layer 15 atomic% or more and 65 atomic% or less is preferable. That is, the content ratio of nickel in the metal element contained in the blackened layer is preferably 15 atomic% or more and 65 atomic% or less. The content of nickel in the metal element contained in the blackening layer is more preferably 25 atomic% or more and 55 atomic% or less.

  This is because if the content of nickel in the metal element contained in the blackened layer is less than 15 atomic%, the environmental resistance may be deteriorated. In addition, when the content ratio of nickel in the metal element contained in the blackening layer exceeds 65 atomic%, the etching property may be deteriorated.

  Further, oxygen contained in the blackening layer is preferably 43 atomic percent or more and 60 atomic percent or less, and more preferably 45 atomic percent or more and 55 atomic percent or less.

  This is because the blackened layer is sufficiently oxidized by the content of 43 atomic% or more of oxygen in the blackened layer, and can be maintained sufficiently black without being oxidized by oxygen and moisture in the air, ie, It is because environmental resistance can be improved. When the content of oxygen in the blackened layer is more than 60 atomic%, the blackened layer becomes transparent and the reflection of the copper film on the short wavelength side shorter than 600 nm increases and does not blacken, and the sheet resistance of the blackened layer is In order to become high, it is preferable that it is 60 atomic% or less.

Oxygen, copper, nickel and molybdenum may be contained in any form in the formed blackened layer. For example, copper and molybdenum may form a mixed sintered body, and a copper-molybdenum mixed sintered body containing oxygen may be contained in the blackened layer. Moreover, copper, nickel or molybdenum is, for example, copper oxide (Cu ₂ O, CuO, Cu ₂ O ₃ ), nickel oxide (NiO), molybdenum oxide (MoO ₃ , MoO ₂ , Mo ₂ O ₃ ), copper-molybdenum oxide One or more selected from oxides (CuMoO ₄ , Cu ₂ MoO _5, Cu ₆ Mo ₄ O ₁₅ , Cu ₃ Mo ₂ O ₉ , Cu ₂ Mo ₃ O ₁₀ , Cu ₄ Mo ₃ O ₁₂ etc.), It may be included in the blackening layer.

  The blackening layer may be, for example, a layer composed of only one kind of substance simultaneously containing oxygen, copper, nickel and molybdenum, such as a copper-nickel-molybdenum mixture containing oxygen. For example, it contains one or more kinds of substances selected from the above-described oxygen-containing copper-molybdenum mixed sintered body, oxides of copper, oxides of nickel, oxides of molybdenum, oxides of copper-molybdenum, etc. Layer may be used.

  The thickness of the blackening layer is not particularly limited, but is preferably, for example, 20 nm or more, and more preferably 25 nm or more. The blackening layer is black as described above and functions as a blackening layer that suppresses the reflection of light by the copper layer, but when the thickness of the blackening layer is thin, sufficient blackness can be obtained. In some cases, the reflection of light by the copper layer can not be sufficiently suppressed. On the other hand, by setting the thickness of the blackening layer in the above range, the reflection of the copper layer can be further suppressed, which is preferable.

The upper limit of the thickness of the blackened layer is not particularly limited, but when the thickness of the blackened layer is increased, the reflectance of the optical characteristics, the lightness (L ^* ), the chromaticity (a ^* , b ^* ) However, it is not preferable because the blackening layer may have inferior characteristics. Therefore, the thickness of the blackening layer is preferably 45 nm or less, more preferably 40 nm or less.

  In addition, when the sheet resistance is sufficiently small, the blackened layer can form a contact portion with an electrical member such as wiring in the blackened layer, and the copper layer is exposed even when the blackened layer is located on the outermost surface It is preferable because it is not necessary.

  And in order to form a contact part with electrical members, such as wiring, in a blackening layer, as sheet resistance of a blackening layer, it is preferable that it is less than 1 k ohms / square.

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

  As described above, the conductive substrate of the present embodiment includes the transparent substrate, the copper layer, and the blackened layer containing oxygen, copper, nickel and molybdenum. Under the present circumstances, the order of lamination | stacking at the time of arrange | positioning a copper layer and a blackening layer on a transparent base material is not specifically limited. Moreover, a copper layer and a blackening layer can also be formed in multiple layers, respectively. In addition, in order to suppress the reflection of light on the surface of the copper layer, it is preferable that a blackening layer is disposed on the surface of the copper layer on which the reflection of light is to be particularly suppressed. Moreover, it is more preferable that the copper layer has a structure sandwiched by the blackening layer.

  Furthermore, when the blackening layer having a small sheet resistance is included as described above, the blackening layer having a small sheet resistance is preferably disposed on the outermost surface of the conductive substrate. This is because the blackened layer having a small sheet resistance can be connected to an electrical member such as a wiring, and therefore, it is preferable that the blackened layer be disposed on the outermost surface of the conductive substrate so as to be easily connected.

  A specific configuration example will be described below using FIGS. 1 and 2. 1 and 2 show an example of a cross-sectional view in a plane parallel to the laminating direction of the transparent base, the copper layer, and the blackening layer of the conductive substrate of the present embodiment.

  For example, as in the case of the conductive substrate 10A shown in FIG. 1A, the copper layer 12 and the blackening layer 13 can be stacked one by one on the one surface 11a side of the transparent substrate 11 in this order. . Further, as in the case of the conductive substrate 10B shown in FIG. 1 (b), copper layers 12A and 12B are formed on one surface 11a side of the transparent substrate 11 and the other surface (the other surface) 11b side. And the blackening layers 13A and 13B can be stacked one by one in this order. The order in which the copper layer 12 (12A, 12B) and the blackening layer 13 (13A, 13B) are stacked is not limited to the examples shown in FIGS. 1 (a) and 1 (b). It is also possible to laminate the metallized layer 13 (13A, 13B) and the copper layer 12 (12A, 12B) in this order.

  Further, for example, a plurality of blackening layers may be provided on one surface 11 a side of the transparent substrate 11. For example, as in the case of the conductive substrate 20A shown in FIG. 2A, the first blackening layer 131, the copper layer 12, and the second blackening layer 132 are provided on the side of one surface 11a of the transparent substrate 11. And can be stacked in that order.

  Also in this case, a copper layer, a first blackening layer, and a second blackening layer can be laminated on both sides of the transparent substrate 11. Specifically, as in the conductive substrate 20B shown in FIG. 2 (b), the first surface 11a of the transparent substrate 11 and the other surface (the other surface) 11b are firstly provided. The blackening layers 131A and 131B, the copper layers 12A and 12B, and the second blackening layers 132A and 132B can be stacked in this order.

  In FIG.1 (b) and FIG.2 (b), when laminating | stacking a copper layer and a blackening layer on both surfaces of a transparent base material, it laminates | stacks on the upper and lower sides of the transparent base material 11 by setting the transparent base material 11 as a symmetry plane. An example is shown in which the arranged layers are arranged to be symmetrical, but the present invention is not limited to such a form. For example, in FIG. 2B, a configuration in which the copper layer 12 and the blackening layer 13 are laminated in the same order as the configuration of FIG. 1A, as in the configuration of FIG. The layers stacked on the upper and lower sides of the transparent substrate 11 may be asymmetric.

  When a copper layer or the like is formed on one surface 11 a side of the transparent substrate 11 as shown in FIGS. 1A and 2A, one of the transparent substrate 11 is formed as described above. It is preferable to perform easy adhesion processing on the surface 11a. When a copper layer or the like is formed on one surface 11a side and the other surface 11b side of the transparent substrate 11 as shown in FIGS. 1 (b) and 2 (b), one surface 11a and the other are formed. It is preferable to perform easy adhesion processing on both sides of the surface 11b.

  So far, the conductive substrate of the present embodiment has been described, but in the conductive substrate of the present embodiment, since the copper layer and the blackening layer are provided on the transparent substrate, the light by the copper layer is provided. Reflection can be suppressed.

  The degree of reflection of light of the conductive substrate of the present embodiment is not particularly limited. For example, in the conductive substrate of the present embodiment, the reflectance of light having a wavelength of 550 nm is preferably 30% or less, and 20% or less Is more preferably 10% or less.

  Further, in the conductive substrate of the present embodiment, the visible light average reflectance, which is an average value of the reflectance with respect to light in the wavelength range of 350 nm to 780 nm, is preferably 30% or less, and 20% or less It is more preferably 10% or less.

  The average value of reflectance (visible light average reflectance) for light in the wavelength range of 350 nm to 780 nm changes the wavelength of light in the wavelength range of 350 nm to 780 nm at predetermined intervals, for example, at 1 nm intervals, It means an average value when the reflectance is measured by irradiating the blackened layer.

  This is because, when at least one of the reflectance of light having a wavelength of 550 nm and the average reflectance of visible light is 30% or less, it causes almost no reduction in the visibility of the display even when used as a conductive substrate for a touch panel, for example. is there. It is more preferable that the reflectance of light with a wavelength of 550 nm and the visible light average reflectance are both 30% or less from the viewpoint of particularly suppressing a decrease in the visibility of the display.

  The measurement of reflectance can be performed by irradiating light to the blackened layer. That is, of the copper layer and the blackening layer contained in the conductive substrate, the measurement can be performed from the blackening layer side.

  Specifically, for example, when the copper layer 12 and the blackening layer 13 are laminated in this order on one surface 11a of the transparent substrate 11 as shown in FIG. 1A, black can be irradiated so that the blackening layer 13 can be irradiated. The surface A of the passivation layer 13 can be measured by irradiating light.

  When the arrangement of the copper layer 12 and the blackening layer 13 is changed and the blackening layer 13 and the copper layer 12 are laminated in this order on one surface 11 a of the transparent substrate 11 in the case of FIG. The reflectance can be measured by irradiating light to the surface of the blackened layer 13 from the side of the surface 11 b of the transparent substrate 11 which is the side where the blackened layer 13 is located on the outermost surface except the material 11.

  In addition, although a conductive substrate can form wiring by etching a copper layer and a blackening layer as mentioned later, the said reflectance is arrange | positioned at the outermost surface when a transparent base material is remove | excluded among conductive substrates. It shows the reflectance of the surface on the light incident side of the blackening layer. For this reason, it is preferable that the measurement value in the part in which the copper layer and the blackening layer remain | survive satisfy | fills the said range before an etching process or after performing an etching process.

Moreover, lightness (L ^* ) and chromaticity (a ^* , b ^* ) can be calculated from the measured reflectance. The lightness (L ^* ) and the chromaticity (a ^* , b ^* ) are not particularly limited, but the lightness (L ^* ) is preferably 60 or less, more preferably 55 or less. In addition, it is preferable that at least one of the chromaticity (a ^* , b ^* ) be less than 0, ie, negative, and it is more preferable that both a ^* and b ^* be less than 0.

This is because, when the lightness (L ^* ) is 60 or less, a dark color tone is obtained, so that the reflection of light can be particularly suppressed. In addition, when at least one of the chromaticity (a ^* , b ^* ) is less than 0, the blackened layer is a color particularly suitable for suppressing the reflection of light.

  The conductive substrate of the present embodiment can be preferably used, for example, as a conductive substrate for a touch panel as described above. 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 copper 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 shows a view of the conductive substrate 30 provided with the mesh-like wiring as viewed from the upper surface side in the lamination direction of the copper layer and the blackening layer, and also shows the wiring 31B seen through the transparent base material 11. . The conductive substrate 30 shown in FIG. 3 has a transparent base 11, a plurality of wires 31A parallel to the Y-axis direction in the figure, and a wire 31B parallel to the X-axis direction. The wirings 31A and 31B are formed by etching a copper layer, and a blackening layer (not shown) is formed on the upper surface and / or the lower surface of the wirings 31A and 31B. The blackening layer is etched to have the same pattern 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.4 (a), (b). 4 (a) and 4 (b) correspond to cross-sectional views taken along the line A-A '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 this case, blackened layers 32A and 32B etched in the same shape as the wirings are disposed on the upper surfaces of the wirings 31A and 31B.

  Further, as shown in FIG. 4B, the wires 31A and 31B are disposed on the upper and lower surfaces of the transparent base material 11A using the pair of transparent base materials 11A and 11B with the one transparent base material 11A interposed therebetween. 31B may be disposed between the transparent substrate 11A and the transparent substrate 11B. 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, the arrangement of the blackening layer and the copper layer is not limited. For this reason, the arrangement of the blackening layers 32A and 32B and the wirings 31A and 31B can be reversed up and down in either case of FIGS. 4 (a) and 4 (b). Also, for example, a plurality of blackening layers can be provided.

  However, it is preferable that the blackening layer is disposed on the surface of the copper layer on which it is desired to particularly suppress the reflection of light.

  Therefore, for example, in the conductive substrate shown in FIG. 4A, the positions of the wiring 31A and the blackening layer 32A and / or the wiring 31B and the blackening layer 32B can be reversed. In addition, a blackening layer may be further provided between the wiring 31A and the transparent base 11, and / or between the wiring 31B and the transparent base 11.

  Then, in the case of the conductive substrate shown in FIG. 4B, for example, when it is necessary to suppress the reflection of light from the lower surface side in the figure, the positions of the blackening layers 32A and 32B; Preferably, the positions of the wires 31A and 31B are reversed. In addition to the blackening layers 32A and 32B, a blackening layer may be further provided between the wiring 31A and the transparent base 11A and / or between the wiring 31B and the transparent base 11B.

  When the blackening layer is further provided in FIGS. 4A and 4B as described above, the blackening layer further provided has the same pattern as the wiring in contact with the blackening layer. It is preferable to be patterned.

  The conductive substrate having the mesh-like wiring shown in FIG. 3 and FIG. 4 (a) is, for example, copper layers 12A and 12B on both sides of the transparent substrate 11 as shown in FIG. 1 (b) and FIG. 2 (b). And blackening layers 13A, 13B (131A, 132A, 131B, 132B).

  In the case where the conductive substrate shown in FIG. 1 (b) is used as an example, first, the copper layer 12A and the blackening layer 13A on the side 11a of the transparent substrate 11 are shown in FIG. 1 (b). Etching is performed so that a plurality of linear patterns parallel to the Y-axis direction are arranged at predetermined intervals along the X-axis direction. The Y-axis direction in FIG. 1 (b) means the direction perpendicular to the paper surface in FIG. 1 (b).

  Then, the copper layer 12B and the blackening layer 13B on the other surface 11b side of the transparent substrate 11 are arranged with a plurality of linear patterns parallel to the X-axis direction in FIG. Etch to make The X-axis direction in FIG. 1 (b) means a direction parallel to the width direction of each layer included in the conductive substrate 10B shown in FIG. 1 (b).

  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 copper layers 12A and 12B and the blackening layers 13A and 13B may be performed simultaneously.

  When a conductive substrate having a mesh-like wiring is similarly formed using conductive substrate 20B shown in FIG. 2 (b), in FIG. 4 (a), wirings 31A and 31B and a transparent base material A blackening layer patterned so as to have the same pattern as the interconnections 31A and 31B is disposed between them.

  The conductive substrate having the mesh-like wiring shown in FIG. 3 can also be formed by using two conductive substrates shown in FIG. 1 (a) or FIG. 2 (a). When the conductive substrate shown in FIG. 1A is used as an example, the copper layer 12 and the blackening layer 13 are parallel to the X-axis direction for the two conductive substrates shown in FIG. 1A. Etching is performed such that a plurality of linear patterns are arranged at predetermined intervals. 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 together when bonding two conductive substrates is not particularly limited, and the surface A in FIG. 1 (a) on which the copper layer 12 and the like are stacked as shown in FIG. 4 (b), and copper You may bond together the surface 11b in FIG. 1 (a) in which layer 12 grade | etc., Is not laminated | stacked.

  In addition, it is preferable that the blackening layer is disposed on the surface of the copper layer on which light reflection is particularly desired to be suppressed. For this reason, in the conductive substrate shown in FIG. 4B, when it is necessary to suppress the reflection of light from the lower surface side in the figure, the positions of the blackening layers 32A, 32B and the wires 31A, 31B. It is preferable to arrange the positions opposite to each other. In addition to the blackening layers 32A and 32B, a blackening layer may be further provided between the wiring 31A and the transparent base 11A and / or between the wiring 31B and the transparent base 11B.

  Further, for example, the surfaces 11b in FIG. 1A where the copper layer 12 and the like of the transparent base material 11 are not laminated may be bonded so that the cross section has a structure shown in FIG. .

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

  Moreover, although the example which formed mesh-like wiring (wiring pattern) combining the wiring of linear shape in FIG. 3, FIG. 4 is shown, it is not limited to the form which concerns, A wiring pattern is comprised The wiring can be of any shape. 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.
(Method of manufacturing conductive substrate)
Next, a configuration example of the method of manufacturing the conductive substrate of the present embodiment will be described.

The method of manufacturing a conductive substrate of the present embodiment is
A transparent substrate preparation step of preparing a transparent substrate;
A copper layer forming step of forming a copper layer on at least one surface side of the transparent substrate;
And a blackening layer forming step of forming a blackening layer containing oxygen, copper, nickel and molybdenum on at least one surface side of the transparent substrate.
The blackened layer contains oxygen in the range of 43 atomic percent to 60 atomic percent, and the total content of copper, nickel, and molybdenum in the blackened layer is 100 atomic percent. The content of molybdenum is preferably 5 atomic% or more.

  Although the manufacturing method of the conductive substrate of this embodiment is explained below, since it can set it as the case of the above-mentioned conductive substrate except the point explained below, explanation is partially omitted.

  As described above, in the conductive substrate of the present embodiment, the order of lamination when the copper layer and the blackening layer are disposed on the transparent substrate is not particularly limited. Moreover, a copper layer and a blackening layer can also be formed in multiple layers, respectively. Therefore, the order of the copper layer forming step and the blackening layer forming step, and the number of times to carry out the step are not particularly limited, and the step is carried out any number of times according to the structure of the conductive substrate to be formed. be able to.

  The step of preparing the transparent substrate is, for example, a step of preparing a transparent substrate made of an insulator film transmitting visible light, a glass substrate or the like, and the specific operation is not particularly limited. For example, cutting or the like to an arbitrary size can be performed as needed to be provided to each subsequent step.

  In addition, about the film which can be used especially suitably as an insulator film which permeate | transmits visible light, since it is stated above, description is abbreviate | omitted here.

  In addition, the transparent base material preparing step is carried out in the transparent base material preparing step from the viewpoint of enhancing the adhesion with the copper layer or the blackening layer and preventing the copper layer and the like formed on the transparent base material from peeling off. Among the above, it is preferable to carry out the easy adhesion treatment on the surface on which the copper layer is to be formed (the easy adhesion treatment step).

  The method of easy adhesion treatment is not particularly limited, and any treatment that can enhance the adhesion to a copper layer or the like is sufficient.

  Specifically, for example, there is a method of making the surface of the transparent substrate hydrophilic by applying a p-methyl methacrylate or the like to the surface of the transparent substrate on which the copper layer and the like are to be formed to form an easy adhesion layer. .

  In addition, as another method of easy adhesion treatment, a method of performing atmospheric pressure plasma treatment on the surface of the transparent substrate on which a copper layer or the like is to be formed, or irradiating Ar ion on a surface of the transparent substrate on which the copper layer or the like is to be formed Methods etc.

  The degree of easy adhesion treatment is not particularly limited. For example, the wet tension of the surface of the transparent substrate on which the copper layer is to be formed is preferably 35 mN / m or more, and 40 mN / m or more It is more preferable that

  The wettability of the transparent substrate can be evaluated by the wet tension test method (JIS K6768 (1999)).

  In addition, with the surface of the side which forms the copper layer of the above-mentioned transparent base, not only the field in which a copper layer is directly formed on a transparent base but a copper layer is via a blackening layer on a transparent base It can include the surface to be formed.

  The easy adhesion treatment is not limited to the side of the transparent base on which the copper layer is formed, but may be performed on the side on which the copper layer is not disposed. However, it is preferable from the viewpoint of productivity and the like to carry out the easy adhesion treatment only on the side on which the copper layer is required to be improved in adhesion to the copper layer or the like.

  Next, the copper layer forming process will be described.

  As described above, the copper layer preferably has a copper thin film layer. Moreover, it can also have a copper thin film layer and a copper plating layer. Therefore, the copper layer forming step can include, for example, a copper thin film layer forming step of forming a copper thin film layer by a dry plating method. In the copper layer forming step, a copper thin film layer forming step of forming a copper thin film layer by dry plating method, and a copper plating layer forming step of forming a copper plating layer by wet plating method using the copper thin film layer as a feed layer. , May be included.

  It does not specifically limit as a dry plating method used for formation of a copper thin film layer, For example, a vacuum evaporation method, sputtering method, or the ion plating method etc. can be used. In particular, as a dry plating method used for forming a copper thin film layer, it is more preferable to use a sputtering method because control of the film thickness is easy.

  The process of forming a copper thin film layer will be described by taking a case of using a winding type sputtering apparatus as an example. First, a copper target is mounted on a cathode for sputtering, and a base material, specifically, a transparent base material, a transparent base material on which a blackening layer is formed, etc. are set in a vacuum chamber. After evacuating the inside of the vacuum chamber, Ar gas is introduced to keep the inside of the apparatus at about 0.13 Pa to 1.3 Pa. In this state, while the substrate is transported from the unwinding roll at a speed of, for example, about 1 m to 20 m per minute, electric power is supplied from the sputtering DC power supply connected to the cathode to carry out sputtering discharge. Can be formed continuously.

  In addition, the specific operation method in a copper thin film layer formation process is not specifically limited, It can implement by arbitrary methods and operation.

  The conditions in the step of forming the copper 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 manner may be adopted. For example, a copper plating layer can be formed by supplying a base on which a copper thin film layer is formed to a plating tank containing a copper plating solution and controlling the current density and the transport speed of the base.

  The thickness of the copper layer formed in the copper layer forming step is not particularly limited, but as described above for the conductive substrate, the thickness of the copper layer is preferably 100 nm or more, and 150 nm or more Is more preferred. The upper limit of the thickness of the copper layer is not particularly limited, but is preferably 3 μm or less, and more preferably 700 nm or less.

  Next, the blackening layer forming step will be described.

  The blackening layer formation step is not particularly limited either, but as described above, the blackening layer can be formed by sputtering.

  At this time, for example, a copper-nickel-molybdenum mixed sintered target or a copper-nickel-molybdenum melted alloy target can be used as a target.

  As described above, although a copper-nickel-molybdenum mixed target and a fused alloy target of copper-nickel-molybdenum can be used alone, one or more kinds selected from copper, nickel and molybdenum can be used alone. It can also be used in combination with a target containing a component.

  Alternatively, as described above, a film can be formed by a dual co-sputtering method using a copper-nickel alloy target and a molybdenum target, or using a copper target and a nickel-molybdenum alloy target.

  The composition of the target used in the sputtering is not particularly limited, and can be arbitrarily selected in accordance with the composition of the blackened layer to be formed. Note that the easiness of elements from the target during sputtering varies depending on the type of element. For this reason, the composition of the target can be selected according to the composition of the target blackened layer and the easiness of the elements in the target.

  For example, it is preferable that the target of copper-nickel-molybdenum mixed sintering contains 5 atomic percent or more and 75 atomic percent or less of molybdenum and 10 atomic percent or more and 50 atomic percent or less of nickel. Further, it is more preferable to contain molybdenum in a ratio of 7 atomic% or more and 65 atomic% or less. The remaining part can be made of copper.

  In addition, when forming a blackened layer by sputtering, the blackened layer can be formed while supplying a gas containing oxygen into the chamber. The supply ratio of oxygen in the gas supplied into the chamber is not particularly limited, and it is in the gas supplied into the chamber at the time of sputtering according to the target composition of the blackened layer and the growth rate of the blackened layer. It is preferable to select the content ratio of oxygen arbitrarily.

  When forming a blackening layer, the content ratio of oxygen in the gas supplied into the chamber is preferably 25% by volume or more and 55% by volume or less, and more preferably 30% by volume or more and 45% by volume or less preferable.

  As described above, in the blackening layer forming step, for example, a copper-nickel-molybdenum mixed sintered target can be used. Therefore, in the blackening layer forming step, for example, a copper-nickel-molybdenum mixed sintering target is used, and a gas containing oxygen in a ratio of 25% by volume or more and 55% by volume or less is supplied by sputtering while being supplied into the chamber. A blackened layer can be formed.

  Note that when sputtering is performed, the gas supplied into the chamber is preferably an inert gas for the remainder other than oxygen. For the remainder other than oxygen, for example, one or more selected from argon, xenon, neon and helium can be supplied.

  The deposited blackened layer can contain oxygen, copper, nickel and molybdenum. The content ratio of each component in the blackened layer is not particularly limited, but the total content of copper, nickel and molybdenum in the blackened layer, ie, the total content of the metal elements contained in the blackened layer Preferably, the content of molybdenum is 5 atomic% or more when the atomic percentage is 100 atomic%. That is, the content ratio of molybdenum in the metal element contained in the blackened layer is preferably 5 atomic% or more.

  This is because the reflectance of light on the surface of the blackened layer can be particularly reduced by setting the content ratio of molybdenum in the metal element contained in the blackened layer to 5 atomic% or more. Also, by setting the content of molybdenum in the metal element contained in the blackened layer to 5 atomic% or more, the amount of oxygen taken into the blackened layer can be increased, and the environmental resistance can be improved. In order to

  However, if the content ratio of molybdenum in the metal element contained in the blackening layer is too large, the reactivity of the blackening layer to the etching solution becomes low, which may make it difficult to form a desired wiring pattern. . Therefore, when the total content of copper, nickel and molybdenum in the blackened layer is 100 atomic%, the content of molybdenum in the blackened layer, ie, molybdenum in the metal element contained in the blackened layer The content ratio of is preferably 40 atomic% or less.

In addition, when the total content of copper, nickel, and molybdenum in the blackened layer, that is, the total content of the metal elements contained in the blackened layer is 100 atomic%, the content of copper in the blackened layer The amount is preferably 30 atomic percent or more and 70 atomic percent or less. That is, the content ratio of copper in the metal element contained in the blackened layer is preferably 30 atomic% or more and 70 atomic% or less. As for the content rate of copper in the metallic element contained in a blackening layer, 40 atomic% or more and 60 atomic% or less are more preferable.
This is because if the content of copper in the metal element contained in the blackened layer is less than 30 atomic%, the etching property may be deteriorated. Moreover, it is because environmental resistance may fall, when the content rate of copper in the metal element contained in a blackening layer exceeds 70 atomic%.

  Furthermore, when the total content of copper, nickel and molybdenum in the blackened layer, that is, the total content of metal elements contained in the blackened layer is 100 atomic%, the content of nickel in the blackened layer 15 atomic% or more and 65 atomic% or less is preferable. That is, the content ratio of nickel in the metal element contained in the blackened layer is preferably 15 atomic% or more and 65 atomic% or less. The content ratio of nickel in the metal element contained in the blackening layer is more preferably 25 atomic% or more and 55 atomic% or less.

  This is because if the content of nickel in the metal element contained in the blackened layer is less than 15 atomic%, the environmental resistance may be deteriorated. In addition, when the content ratio of nickel in the metal element contained in the blackening layer exceeds 65 atomic%, the etching property may be deteriorated.

  Further, oxygen contained in the blackening layer is preferably 43 atomic percent or more and 60 atomic percent or less, and more preferably 45 atomic percent or more and 55 atomic percent or less.

  This is because the blackened layer is sufficiently oxidized by the content of 43 atomic% or more of oxygen in the blackened layer, and can be maintained sufficiently black without being oxidized by oxygen and moisture in the air, ie, It is because environmental resistance can be improved. When the content of oxygen in the blackened layer is more than 60 atomic%, the blackened layer becomes transparent and the reflection of the copper film on the short wavelength side shorter than 600 nm increases and does not blacken, and the sheet resistance of the blackened layer is In order to become high, it is preferable that it is 60 atomic% or less.

Oxygen, copper, nickel and molybdenum may be contained in any form in the formed blackened layer. For example, copper and molybdenum may form a mixed sintered body, and a copper-molybdenum mixed sintered body containing oxygen may be contained in the blackened layer. Moreover, copper, nickel or molybdenum is, for example, copper oxide (Cu ₂ O, CuO, Cu ₂ O ₃ ), nickel oxide (NiO), molybdenum oxide (MoO ₃ , MoO ₂ , Mo ₂ O ₃ ), copper-molybdenum oxide One or more selected from oxides (CuMoO ₄ , Cu ₂ MoO _5, Cu ₆ Mo ₄ O ₁₅ , Cu ₃ Mo ₂ O ₉ , Cu ₂ Mo ₃ O ₁₀ , Cu ₄ Mo ₃ O ₁₂ etc.), It may be included in the blackening layer.

  The blackening layer may be, for example, a layer composed of only one kind of substance simultaneously containing oxygen, copper, nickel and molybdenum, such as a copper-nickel-molybdenum mixture containing oxygen. For example, it contains one or more kinds of substances selected from the above-described oxygen-containing copper-molybdenum mixed sintered body, oxides of copper, oxides of nickel, oxides of molybdenum, oxides of copper-molybdenum, etc. Layer may be used.

  Then, when the sheet resistance is sufficiently small, the formed blackened layer can form a contact portion with an electrical member such as wiring in the blackened layer, and the copper layer is formed even when the blackened layer is located on the outermost surface It is preferable because it is not necessary to expose.

  The thickness of the blackening layer formed in the blackening layer formation step is not particularly limited, but as described above for the conductive substrate, for example, it is preferably 20 nm or more, and more preferably 25 nm or more preferable. The upper limit of the thickness of the blackening layer is not particularly limited, but is preferably 45 nm or less, and more preferably 40 nm or less.

  The conductive substrate obtained by the method of manufacturing a conductive substrate described herein can be a conductive substrate provided with mesh-like wiring. In this case, in addition to the above-described steps, an etching step of forming a wiring by etching the copper layer and the blackening layer can be further included.

  In the etching step, for example, a resist having an opening corresponding to a portion to be removed by etching is first formed on the outermost surface of the conductive substrate. In the case of the conductive substrate shown in FIG. 1A, a resist can be formed on the exposed surface A of the blackening layer 13 disposed on the conductive substrate. Although a method for forming a resist having an opening corresponding to a portion to be removed by etching is not particularly limited, for example, the resist can be formed by photolithography.

  Then, the copper layer 12 and the blackening layer 13 can be etched by supplying an etching solution from the top of the resist.

  In addition, when a copper layer and a blackening layer are arrange | positioned on both surfaces of the transparent base material 11 like FIG. 1 (b), the resist which has an opening part of the predetermined shape in the surfaces A and B of a conductive substrate, respectively. The copper layer and the blackening layer formed on both sides of the transparent substrate 11 may be simultaneously etched.

  In addition, with respect to the copper layer and the blackening layer formed on both sides of the transparent substrate 11, it is also possible to perform an etching process on one side. That is, for example, after the copper layer 12A and the blackening layer 13A are etched, the copper layer 12B and the blackening layer 13B may be etched.

  The blackening layer formed by the method of manufacturing a conductive substrate of the present embodiment exhibits the same reactivity to the etching solution as the copper layer. Therefore, the etching solution used in the etching step is not particularly limited, and an etching solution generally used for etching a copper layer can be preferably used. As an etching solution, for example, a mixed aqueous solution of ferric chloride and hydrochloric acid can be more preferably used. The content of ferric chloride in the etching solution and hydrochloric acid is not particularly limited. For example, it is preferable to include ferric chloride in a proportion of 5% by mass to 50% by mass, and 10% by mass It is more preferable to contain in the ratio of 30 mass% or less. Further, for example, the etching solution preferably contains hydrochloric acid in a proportion of 1% by mass to 50% by mass, and more preferably in a proportion of 1% by mass to 20% by mass. The remaining part can be water.

  The etching solution can be used at room temperature, but can also be used by heating to enhance the reactivity, for example, it can be used by heating to 40 ° C. or more and 50 ° C. or less.

  The specific form of the mesh-like wiring obtained by the above-described etching process is as described above, and thus the description thereof is omitted here.

  Also, as described above, two conductive substrates having a copper layer and a blackening layer on one side of the transparent substrate 11 shown in FIGS. 1 (a) and 2 (a) are attached and meshed. When it is set as the conductive substrate provided with the shape wiring, the process of bonding a conductive substrate can further be provided. Under the present circumstances, the method to bond two conductive substrates together is not specifically limited, For example, it can adhere using an adhesive agent etc.

  The conductive substrate and the method of manufacturing the conductive substrate according to the present embodiment have been described above. The conductive substrate is provided with a blackened layer excellent in environmental resistance. Therefore, it is possible to suppress the occurrence of discoloration in the blackened layer even in an environment exposed to high temperature and high humidity, such as outdoors, and it is possible to maintain the effect of improving the visibility by the blackened layer Become.

  Hereinafter, the present invention will be described in more detail by way of examples of the present invention and comparative examples, but the present invention is not limited by these examples.

First, the evaluation method of the sample produced in each experiment example mentioned later is explained.
(Evaluation method)
(1) Optical characteristics (reflectance, brightness, chromaticity)
The optical characteristics (reflectance) were measured on the conductive substrate produced in the following experimental examples, and the light characteristics (reflectance) were measured as necessary, and the lightness (L ^* ) and the chromaticity (a ^* , b ^* ) were measured ^. ) Was calculated.

  The measurement of the reflectance was performed by installing a reflectance measurement unit in an ultraviolet-visible spectrophotometer (manufactured by Hitachi High-Technologies Corporation, model: U-4000).

  In Experimental Example 2 below, a conductive substrate having a cross-sectional shape similar to that of FIG. 1A was produced. Therefore, the incident angle 5 ° and the light reception angle 5 ° with respect to the surface A in FIG. 1A on the side on which the copper layer and the blackening layer of the produced conductive substrate are formed have wavelengths in the range of 350 nm to 780 nm. The reflectance when irradiated with light was measured. In addition, in the case of the measurement, the light which changed the wavelength for every 1 nm was irradiated in wavelength 350nm-780nm or more, and the reflectance about each wavelength was measured.

  And the measured value of the reflectance with respect to the light of wavelength 550nm was made into the reflectance with respect to the light of wavelength 550nm.

  In addition, in order to correct | amend the curvature of a PET film in the case of a measurement, the sample of each experimental example was mounted on a glass substrate, it fixed by clamp, and light was irradiated and measured from the blackening layer side.

From the measured reflectance, using the color calculation program based on JIS Z8781-4: 2013, calculate the coordinates on the CIE 1976 (L ^* , a ^* , b ^* ) color space under the conditions of light source A, field of view 2 degrees did.
(2) Dissolution Test The dissolution test of the blackened layer was carried out by immersing the sample having the blackened layer formed on the transparent substrate prepared in Experimental Example 1 below in an etching solution.

  As an etching solution, an aqueous solution consisting of 10% by mass of ferric chloride used as an etching solution for a copper layer, 10% by mass of hydrochloric acid and the balance water is used, and the temperature of the etching solution is room temperature (25 ° C.). Carried out.

  A 300 nm thick copper layer was formed on the entire surface on one side of a 5 cm long, 5 cm wide and 0.05 mm thick polyethylene terephthalate resin (PET resin) which was the transparent substrate used in Experimental Example 1. A preliminary experiment was conducted in which the sample was immersed in the etching solution. In this case, it has been confirmed that the copper layer dissolves within 10 seconds.

For this reason, when the blackened layer dissolves within 1 minute in the dissolution test, it can be said that it has the same reactivity as the copper layer with respect to the etching solution. The conductive substrate included can be said to be a conductive substrate provided with a copper layer and a blackening layer that can be etched simultaneously.
(3) EDS Analysis With respect to the composition of the blackened layer of the sample having the blackened layer formed on the transparent substrate prepared in Experimental Example 1, a SEM-EDS device (SEM: manufactured by Nippon Denshi Co., Ltd. Model: JSM-7001F, EDS: manufactured by Thermo Fisher Scientific Co., Ltd. Model: Detector UltraDry analysis system NOR System 7) EDS analysis was performed.
(4) Environmental resistance test In Experimental Example 2, the sample having the copper layer and the blackened layer formed on the transparent substrate is placed in a constant temperature and humidity chamber with a temperature of 60 ° C. and a humidity of 90% for 100 hours. The test was done.

The optical properties of the samples before the environmental resistance test and after the environmental resistance test were measured, and evaluations were made based on changes in L ^* , a ^* and b ^* before and after the environmental resistance test.

For evaluation, ΔL ^* , Δa ^* , Δb ^* are calculated by subtracting the values after the environmental resistance test from the values before the environmental resistance test for each sample, and ΔL ^* , Δa ^* , Δb ^* −5-5 ○, -5> ΔL ^* , Δa ^* , Δb ^* ≧ −10 was evaluated as Δ, −10> ΔL ^* , Δa ^* , Δb ^* was evaluated as x. Of the ΔL ^* , Δa ^* , and Δb ^* , the one with the lowest evaluation was taken as the evaluation result of the conductive substrate. For example, [Delta] L ^* is 〇, .DELTA.a ^* is △, when [Delta] b ^* is 〇 is .DELTA.a ^* evaluation results of the lowest evaluation △ becomes the evaluation of the conductive substrate. And, 〇, を was passed, and x was rejected.

  Moreover, after completion | finish of an environmental resistance test, it evaluated as to whether peeling of a copper layer was seen from a transparent base material. Specifically, SEM observation was performed on holes in which holes of about 100 μm to 300 μm were observed, and evaluation was performed as to the presence or absence of peeling of the copper layer. Those with peeling were found to be present, and those with no peeling found to be absent.

The manufacturing conditions of the sample in each experiment example and its evaluation result are demonstrated below.
[Experimental Example 1]
In Experimental Example 1, 28 types of samples of Experimental Example 1-1 to Experimental Example 1-28 shown below were prepared, and EDS analysis and dissolution test on the composition of the blackened layer were performed.

In addition, this experiment example is implemented as a preliminary experiment for experiment example 2 mentioned later, and becomes a reference example.
(About target)
In this experimental example, as described later, a sample in which a blackened layer was formed on a transparent base material was produced, but seven kinds of targets shown in Table 1 below are used when forming the blackened layer. In addition, when forming a blackening layer into a film, it forms into a film by sputtering method using the target shown in the following Table 1 single or two sheets, and when forming into a film using two sheets, two simultaneous simultaneously The film is formed by sputtering.

まず、表１に示したターゲットＮｏ．５、Ｎｏ．６の銅−ニッケル−モリブデン混合焼結ターゲット、すなわちターゲット組成がＣｕ２５Ｎｉ１５Ｍｏ、及びＣｕ４２Ｎｉ１６Ｍｏの銅−ニッケル−モリブデン混合焼結ターゲットの作製方法について説明する。

First, target No. 1 shown in Table 1. 5, no. A method of producing a copper-nickel-molybdenum mixed sintered target of 6, ie, a copper-nickel-molybdenum mixed sintered target having a target composition of Cu25Ni15Mo and Cu42Ni16Mo will be described.

  As starting material powders, Cu powder (3N CUE 13PB <43 μm made by High Purity Chemical), Ni powder (3N NIE 08PB 63 μm made by High Purity Chemical), and Mo powder (made by New Japan Metal, secondary particle diameter about 200 μm to 500 μm) Was weighed and mixed in a mortar. Under the present circumstances, it measured and mixed so that the mixture ratio of the starting material powder about each target might turn into the value (atomic%) shown in the following Table 2.

Subsequently, the mixed powder of the obtained starting material powder is put into a graphite mold having an inner diameter of 3 inches and sintered by a hot press method, and five types of sintered bodies No. 1 to No. 5 of different compositions are sintered. The body was prepared. The contact pressure at the time of sintering by the hot press method was 136 kgf / cm ² , the hot press temperature (HP temperature) was 900 ° C. or 1000 ° C. shown in Table 2, and the holding time was 1 hour. The relative density of the obtained sintered body was 82% to 93% as shown in Table 2, and it could be confirmed that it could be used as a sputter target.

  Therefore, the sintered body No. 1 in which the relative density is particularly high. 3, sintered body No. 4 was used as a sputtering target. Specifically, the sintered body No. The target No. 3 is the target No. 3 in Table 1 described above. In No. 6, the sintered body No. The target No. 4 is the target No. 4 in Table 1 described above. Hit 5 each.

なお、表１に示したターゲットＮｏ．１〜Ｎｏ．４、Ｎｏ．７については、金属単体、または合金、熔解合金を用いてスパッタリングターゲットを作製した。
（試料の作製条件、評価結果）
本実験例では、透明基材であるＰＥＴ基材上に、酸素、銅、ニッケル、及びモリブデンを含有する黒化層を形成した実験例１−１〜実験例１−２８の合計２８個の試料を作製した。具体的な手順について、実験例１−１の場合を例に以下に説明する。

In addition, the target No. shown in Table 1 is. 1 to No. 4, no. As for No. 7, a sputtering target was manufactured using a single metal, an alloy, or a melted alloy.
(Sample preparation conditions, evaluation results)
In this experiment, a total of 28 samples of Experiment 1-1 to Experiment 1-28 in which a blackened layer containing oxygen, copper, nickel, and molybdenum was formed on a PET substrate which is a transparent substrate. Was produced. A specific procedure will be described below by taking the case of Experimental Example 1-1 as an example.

  First, a transparent substrate made of polyethylene terephthalate resin (PET, trade name "Lumirror U48", manufactured by Toray Industries, Inc.) 5 cm long, 5 cm wide, and 0.05 mm thick was prepared.

Then, the prepared transparent substrate was set in the substrate holder of the sputtering apparatus, and the inside of the chamber was evacuated. The ultimate vacuum in the chamber before sputtering was 1.5 × 10 ⁻⁴ Pa.

  After evacuating the chamber, a blackened layer was formed by sputtering. The formation of the blackening layer was performed using a sputtering apparatus (manufactured by ULVAC, Inc. Model: SIH-450).

  As shown in Table 3, when forming a blackened layer, target No. 1 shown in Table 1 was used. A film was formed by supplying power of 200 W to the target using only Cu40Ni of 3. When forming a blackening layer, the film formation was performed by rotating the substrate holder on which the transparent base material was set at a speed of 30 rpm.

  Further, while the blackening layer was formed by sputtering, as shown in Table 3, argon gas was supplied at 5 SCCM and oxygen gas at 5 SCCM, as shown in Table 3.

  In addition, in film-forming of a blackening layer, the power of 200 W was first applied to the target, sputtering was performed for 20 minutes, and the film-forming speed | rate was measured. Then, the film formation time until the film thickness reaches 300 nm was calculated from the measured film formation rate, and a DC power of 200 W was applied to the target again to perform sputtering for a predetermined time to form a 300 nm-thick blackened layer. .

  The blackening layer was formed to have a thickness of 300 nm, and was then taken out of the chamber.

  Among the obtained samples, a part was cut out and subjected to a dissolution test, and the remaining part was subjected to EDS analysis. The results are shown in Table 3.

  In Experimental Example 1-2 to Experimental Example 1-28, when forming the blackened layer, the flow rates of oxygen gas and argon gas in the gas supplied into the target and the chamber in Table 3 are for each experimental example. A sample was produced in the same manner as in Experimental Example 1-1 except that the test was conducted under the conditions shown.

  As described above, depending on the experimental example, two targets were used to perform two-way simultaneous sputtering to form a blackened layer. For example, in Experimental Example 1-2, as shown in Table 3, using a Cu 40 Ni alloy target and a Mo metal target as targets, 160 W and 130 W of power are supplied to the respective targets to form a blackened layer. ing.

  The evaluation results are also shown in Table 3 for Experimental Example 1-2 to Experimental Example 1-28.

[Experimental Example 2]
According to the following procedure, a copper layer and a blackening layer are formed on a transparent substrate, and a conductive substrate having a configuration similar to that of FIG. Evaluation of environmental resistance test was conducted.

  The procedure of manufacturing the conductive substrate will be described by taking the case of Experimental Example 2-1 as an example.

  As a transparent substrate, the same PET substrate as in Experimental Example 1 was used.

Then, the prepared transparent substrate was set in a substrate holder of a sputtering apparatus (manufactured by ULVAC, Inc. Model: SIH-450) equipped with a copper target as a target, and the inside of the chamber was evacuated. The ultimate vacuum in the chamber before sputtering was 1.5 × 10 ⁻⁴ Pa.

  After the inside of the chamber is once evacuated, Ar gas is introduced into the chamber at 0.55 Pa, power of 200 W is supplied to the copper target, and a 300 nm-thick copper layer is formed on the transparent substrate. I made a film.

Next, a blackened layer was formed on the upper surface of the copper layer under the same conditions as in Example 1-1. Incidentally, the film thickness of the blackened layer was formed so as to minimize the optical characteristics, particularly L ^* , that is, the film thickness of 30.3 nm shown in Table 4.

  Also in Experimental Example 2-2 to Experimental Example 2-28, a copper layer was formed in the same manner as in Experimental Example 2-1, and then a blackened layer was formed on the upper surface of the copper layer. The film formation of the blackening layer was performed on each of the samples of Experimental Example 2 under the same conditions as the corresponding Experimental Example of Experimental Example 1 so that the film thickness was the film thickness shown in Table 2.

  In addition, the corresponding experimental example of Experimental example 1 about each sample of Experimental example 2 is the number after Experimental example 1-- and the experimental example 2- in Experimental example 1 as shown also in Table 4. And say the same experiment example. Specifically, for example, Experimental Examples 1-5 and Experimental Examples 2-5 are corresponding experimental examples, and the blackened layer was formed under the same conditions.

  Experimental Example 2-2 to Experimental Example 2-14, Experimental Example 2-18 to Experimental Example 2-20, and Experimental Example 2-23 to Experimental Example 2-27 serve as Examples, and Experimental Example 2-1, and Experimental Example 2- 15 to Experimental Example 2-17, Experimental Example 2-21, Experimental Example 2-22, and Experimental Example 2-28 are comparative examples.

  An environmental resistance test was conducted on the obtained conductive substrate.

  The above evaluation results are shown in Table 4.

なお、既述のように、実験例２の各試料の黒化層は、対応する実験例１の試料と同様の条件で黒化層を形成している。このため、実験例２の各試料の黒化層の組成、及びエッチング特性は、対応する実験例１の試料と同じ特性を有している。このため、表４中に実験例１で評価した黒化層のＥＤＳ分析の結果もあわせて示す。

As described above, the blackened layer of each sample of Experimental Example 2 forms the blackened layer under the same conditions as the corresponding sample of Experimental Example 1. For this reason, the composition of the blackened layer of each of the samples of Experimental Example 2 and the etching characteristics have the same properties as the corresponding samples of Experimental Example 1. Therefore, Table 4 also shows the results of EDS analysis of the blackened layer evaluated in Experimental Example 1.

  According to Table 4, in Experimental Example 2-28, the reflectance of light having a wavelength of 550 nm was extremely high before and after the environmental resistance test in any case, and did not function as a blackening layer.

  For Experimental Example 2-1 to Experimental Example 2-27 except for Experimental Example 2-28, the reflectance of light with a wavelength of 550 nm is 30% or less regardless of before and after the environmental resistance test, and functions as a blackened layer. It was confirmed that it was possible.

  And according to Table 4, when the blackened layer contains 43 atomic percent or more and 60 atomic percent or less of oxygen, and the total content of copper, nickel, and molybdenum in the blackened layer is 100 atomic percent, The experimental example in which the content of molybdenum is 5 atomic% or more has been confirmed that the evaluation of the environmental resistance is 〇 or △. That is, it could be confirmed that it had sufficient environmental resistance.

  Specifically, the evaluation of the environmental resistance is 〇 or Δ for Experimental Example 2-2 to Experimental Example 2-14, Experimental Example 2-18 to Experimental Example 2-20, and Experimental Example 2-23 to Experimental Example 2-27. It could be confirmed that

  However, in Experimental Example 2-4, in the dissolution test of the blackened layer of Experimental Example 1, it has been confirmed that the etching time becomes very long, 180 seconds. This is because the content of molybdenum in the blackened layer was very high at 63 atomic%, and according to the study of the inventors of the present invention, the content of Mo in all the metal elements in the blackened layer is 40 atoms. In the case of% or less, the etching time can be 1 minute or less, which is preferable.

  And when it evaluated about the presence or absence of peeling of the copper layer after an environmental resistance test, as shown in Table 4, in some experiment examples, peeling of the copper layer was observed from the transparent base material.

  Therefore, in order to suppress the peeling of the copper layer, the surface of the transparent substrate on which the copper layer and the like are to be formed is subjected to an easy adhesion treatment of irradiating Ar ions with high frequency plasma to improve the wettability of the substrate. A conductive substrate was produced and evaluated using a base material.

  In addition, when the wet tension was evaluated based on JIS K 6768 (1999) on the surface of the transparent substrate, the sample before the Ar ion irradiation, that is, the above-mentioned experimental example 2-1 to experimental example 2-28 was produced. The transparent substrate used for the test had a wet tension of 31 mNm. On the other hand, when Ar ion irradiation was performed, it was confirmed that the wetting tension was 44 mNm for the surface irradiated with Ar ions.

  As described above, the above-described Experimental Example 2-1 was used except that the transparent substrate having a wetting tension of 44 mNm was used by irradiating Ar ion to the surface of the transparent substrate on which the copper layer and the like are formed. The conductive substrates of Experimental Example 3-1 to Experimental Example 3-28 were produced in the same manner as in Experimental Example 2-28, respectively.

  That is, in Experimental Example 3-1 to Experimental Example 3-28, the experimental example was performed on each sample of Experimental Example 3-1 to Experimental Example 3-28 except that the transparent substrate was subjected to the easy adhesion treatment in advance. A conductive substrate was produced in the same manner as the corresponding experimental example of 2-1 to experimental example 2-28.

  In addition, with regard to each sample of Experimental Example 3-1 to Experimental Example 3-28, the corresponding experimental example of Experimental Example 2-1 to Experimental Example 2-28 is as shown in Table 5 as well. The later numbers and the numbers after Experimental Example 3 refer to the same experimental example.

  Experimental Example 3-2 to Experimental Example 3-14, Experimental Example 3-18 to Experimental Example 3-20, and Experimental Example 3-23 to Experimental Example 3-27 serve as Examples, and Experimental Example 3-1, and Experimental Example 3 15 to Experimental Example 3-17, Experimental Example 3-21, Experimental Example 3-22, and Experimental Example 3-28 are comparative examples.

  The obtained conductive substrate was evaluated for the environmental resistance test and the presence or absence of peeling of the copper layer.

  The results are shown in Table 5.

表５に示した結果によると、いずれの実験例においても銅層の剥離が見られなくなっていることが確認できた。これは透明基材について易密着性処理を施すことで、透明基材と銅層との密着性が高まったためと考えられる。

According to the results shown in Table 5, it was confirmed that peeling of the copper layer was not observed in any of the experimental examples. It is considered that this is because the adhesion between the transparent substrate and the copper layer is enhanced by subjecting the transparent substrate to the easy adhesion treatment.

10A, 10B, 20A, 20B, 30 Conductive substrate 11, 11A, 11B Transparent base 12, 12A, 12B Copper layer 13, 13A, 13B, 131, 132, 131A, 131B, 132A, 132B, 32A, 32B blackening Layer 31A, 31B wiring

Claims (8)

A transparent substrate,
A copper layer disposed on at least one surface side of the transparent substrate;
And a blackening layer disposed on at least one surface side of the transparent substrate and containing oxygen, copper, nickel and molybdenum.
The blackened layer contains 43 atomic percent or more and 60 atomic percent or less of the oxygen,
When the total content of copper, nickel and molybdenum in the blackened layer is 100 atomic%, the content of the molybdenum in the blackened layer is 5 atomic% or more and 40 atomic% or less,
The content of the copper in the blackened layer is 30 atomic% or more and 70 atomic% or less,
The conductive substrate whose content of the said nickel in the said blackening layer is 15 atomic% or more and 65 atomic% or less . The copper layer has a thickness of 100 nm or more,
The conductive substrate according to claim 1 wherein the blackening layer thickness is 40nm or less at 20nm or more. 3. The conductive substrate according to claim 1 , wherein a wet tension of a surface of the transparent base on which the copper layer is disposed is 35 mN / m or more. The conductive substrate according to any one of claims 1 to 3 , wherein the reflectance of light having a wavelength of 550 nm is 30% or less. The conductive substrate according to any one of claims 1 to 4 , further comprising a mesh-like wiring. A transparent substrate preparation step of preparing a transparent substrate;
A copper layer forming step of forming a copper layer on at least one surface side of the transparent substrate;
Forming a blackening layer on at least one surface of the transparent substrate, wherein a blackening layer containing oxygen, copper, nickel and molybdenum is formed;
The blackened layer contains 43 atomic percent or more and 60 atomic percent or less of the oxygen,
When the total content of copper, nickel and molybdenum in the blackened layer is 100 atomic%, the content of the molybdenum in the blackened layer is 5 atomic% or more and 40 atomic% or less,
The content of the copper in the blackened layer is 30 atomic% or more and 70 atomic% or less,
The manufacturing method of the conductive substrate whose content of the said nickel in the said blackening layer is 15 atomic% or more and 65 atomic% or less . In the blackening layer forming step,
Using a copper-nickel-molybdenum mixed sintered target,
The method for manufacturing a conductive substrate according to claim 6 , wherein the blackening layer is formed by sputtering while supplying a gas containing oxygen at a ratio of 25% by volume to 55% by volume into the chamber. 8. The transparent substrate preparation step according to claim 6 , wherein an easy adhesion treatment is performed on the surface of the transparent substrate on which the copper layer is to be formed, and the wet tension is 35 mN / m or more. Method of manufacturing a conductive substrate.

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