JP2015184994A - Transparent conductive laminate and touch panel having transparent conductive laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transparent conductive laminate and a touch panel having the transparent conductive laminate, capable of avoiding malfunction under high temperature and high humidity.SOLUTION: A transparent conductive laminate includes a transparent base material and a transparent electrode layer laminated on one or two of sides of the transparent base material and including resin. The transparent electrode layer includes a plurality of conductive regions having fibrous metal and non-conductive regions. An electric resistance value between conductive regions neighbouring via non-conductive regions is 10Ω or higher when 240 hours have lapsed after being put into an atmosphere at a temperature of 60°C and humidity of 90%.

Description

  The technology of the present disclosure relates to a transparent conductive laminate and a touch panel including the transparent conductive laminate.

  In recent years, capacitive touch panels have been widely used as input devices for electronic devices. A projected capacitive touch panel includes two electrodes for detecting a change in capacitance. The two electrodes are opposed via a transparent substrate. These electrodes are formed by patterning a transparent conductive film formed on a substrate.

  A typical material for a transparent conductive film formed on a substrate as an electrode is indium tin oxide (ITO). A method of forming a film of ITO on a substrate is a vacuum film formation in a dry method. However, indium, which is the main component of ITO, is a rare metal and there is a concern about stable supply, and there is also a problem that it lacks flexibility. In addition, the manufacturing method also requires an expensive vacuum film forming apparatus, resulting in a problem of high cost.

  In recent years, in view of the above problems, ITO substitute materials have emerged, and conductive films are formed by processing conductive polymers, carbon nanotubes, and metals into a fibrous or mesh shape. Some of these can be dispersed in water or an organic solvent. If they are used, the dispersion can be applied to the substrate surface by a wet method, and mass production and cost reduction are also expected. The In particular, a base material on which a conductive film is formed by forming a metal into a fiber or mesh shape is regarded as a promising alternative to ITO in that a resistance value and optical characteristics equivalent to those of ITO can be obtained.

  A touch panel made of fibrous metal as a conductive film works normally, but if it is put in a high-temperature and high-humidity environment, problems such as erroneous recognition of the touch position and a decrease in the capacitance value occur, and it is durable against high-temperature and high-humidity environments. There is a problem that there is no sex. The cause of malfunction is considered to be migration of the fibrous metal constituting the electrode. In migration, when a voltage is applied to an electrode under high temperature and high humidity, the metal forming the electrode is ionized on the anode side due to the presence of moisture and moves to the electrode on the cathode side. The deposited metal is a phenomenon in which the surface of the insulator grows in the shape of a tree, a bridge, or a cloud. When this growth reaches the anode side, a short circuit occurs and becomes defective. A base material used as a touch panel has a plurality of rod-shaped or diamond-shaped electrodes arranged in parallel, and the adjacent electrodes are insulated by etching. In order to drive the base material as a touch panel, a wiring is formed on each electrode, and a voltage is applied to each electrode and driven by an IC circuit via a flexible printed plate (FPC). Since a voltage is applied to each electrode, adjacent electrodes that generate a potential difference migrate due to the fibrous metal constituting the electrode under the influence of moisture at high temperatures, resulting in a decrease in capacitance or short-circuiting of the electrodes. Wake up and cannot operate normally as a touch panel.

  In order to solve this problem, there is a technique that prevents migration by blocking moisture. For example, in Patent Document 1, a water shielding layer is provided so that moisture does not enter and migration does not occur. However, the increase in the number of layers may increase the thickness of the touch panel, increase the number of materials, increase the number of processes, and increase the cost.

JP 2013-097932 A

  The present invention has been made in view of the above problems, and an object thereof is to provide a transparent conductive laminate and a touch panel that do not malfunction under high temperature and high humidity.

One aspect of the present invention for solving the above problems includes a transparent base material, a transparent base material, and a transparent electrode layer that is laminated on one or both surfaces of the transparent base material and includes a resin. Including a plurality of conductive regions and a non-conductive region having a metal-like shape, and the electric current between adjacent conductive regions via the non-conductive region after 240 hours have passed after being placed in an atmosphere of a temperature of 60 ° C. and a humidity of 90% It is a transparent conductive laminate having a resistance value of 10 ⁹ Ω or more.

  Further, the thickness of the transparent electrode layer may be 30 nm or more and 150 nm or less.

  Moreover, the other situation of this invention is a touch panel provided with the above-mentioned transparent conductive laminated body.

  With the transparent conductive laminate according to the technique of the present disclosure, it is possible to provide a touch panel with improved durability in which short-circuiting between electrodes due to migration hardly occurs and malfunction does not occur in a high-temperature and high-humidity atmosphere.

It is sectional drawing which shows 1st Embodiment of the transparent conductive laminated body in the technique of this indication. It is sectional drawing which shows 2nd Embodiment of the transparent conductive laminated body in the technique of this indication. It is sectional drawing which shows 3rd Embodiment of the transparent conductive laminated body in the technique of this indication. It is a top view when the electroconductive area | region of the transparent electrode layer of the transparent conductive laminated body in the technique of this indication is formed in mesh shape. It is a top view when the electroconductive area | region of the transparent electrode layer of the transparent conductive laminated body in the technique of this indication is formed in strip shape. It is a figure which shows a mode that the voltage was applied to the two adjacent conductive area | regions of the transparent electrode layer of the transparent conductive laminated body in the technique of this indication. It is sectional drawing which shows the touchscreen in one Embodiment in the technique of this indication. It is a figure which shows the manufacturing process of the transparent conductive laminated body in the technique of this indication, Comprising: It is a figure which shows the formation process of the metal layer in the surface side of a board | substrate. It is a figure which shows the manufacturing process of the transparent conductive laminated body in the technique of this indication, Comprising: It is a figure which shows the formation process of the transparent conductive layer in the surface side of a board | substrate. It is a figure which shows the manufacturing process of the transparent conductive laminated body in the technique of this indication, Comprising: It is a figure which shows the formation process of the transparent conductive layer in the back surface side of a board | substrate. It is a figure which shows the manufacturing process of the transparent conductive laminated body in the technique of this indication, Comprising: It is a figure which shows the formation process of a resist. It is a figure which shows the manufacturing process of the transparent conductive laminated body in the technique of this indication, Comprising: It is a figure which shows an exposure process. It is a figure which shows the manufacturing process of the transparent conductive laminated body in the technique of this indication, Comprising: It is a figure which shows a image development process. It is a figure which shows the manufacturing process of the transparent conductive laminated body in the technique of this indication, Comprising: It is a figure which shows an etching process. It is a figure which shows the manufacturing process of the transparent conductive laminated body in the technique of this indication, Comprising: It is a figure which shows the removal process of a resist.

  With reference to the drawings, a transparent conductive laminate, a touch panel, and a method for manufacturing the transparent conductive laminate in the technology of the present disclosure will be described. In this embodiment, a transparent conductive laminated body is one of the structural members of a touch panel.

[Configuration of transparent conductive laminate]
In FIG. 1, sectional drawing of 1st Embodiment of a transparent conductive laminated body is shown. As shown in FIG. 1, the transparent conductive laminate 10 includes a transparent substrate 11 (transparent base material), and a transparent electrode layer 12 a formed on the surface of the substrate 11 (above the paper surface of FIG. 1, the same applies hereinafter). And a transparent electrode layer 12b formed on the back surface of the substrate 11 (below the paper surface in FIG. 1, the same applies hereinafter). The two transparent electrode layers 12a and 12b are opposed to each other with the substrate 11 interposed therebetween. The transparent electrode layer 12a is an example of a first transparent electrode layer, and the transparent electrode layer 12b is an example of a second transparent electrode layer.

  In FIG. 2, sectional drawing of 2nd Embodiment of a transparent conductive laminated body is shown. As shown in FIG. 2, the transparent conductive laminate 20 was formed on the transparent substrate 11a, the transparent electrode layer 12a formed on the surface of the substrate 11a, the transparent substrate 11b, and the surface of the substrate 11b. It comprises a transparent electrode layer 12b and an adhesive layer 23 that bonds the substrate 11a and the transparent electrode layer 12b together.

  In FIG. 3, sectional drawing of 3rd Embodiment of a transparent conductive laminated body is shown. As shown in FIG. 3, the transparent conductive laminate 30 was formed on the transparent substrate 11a, the transparent electrode layer 12a formed on the surface of the substrate 11a, the transparent substrate 11b, and the surface of the substrate 11b. It comprises a transparent electrode layer 12b and an adhesive layer 23 that bonds the substrate 11a and the substrate 11b together.

  With reference to FIG. 1, the structure of a transparent conductive laminated body is demonstrated.

  As the substrate 11, for example, glass or a resin film is used. The resin used for the resin film is not limited as long as the formed film has the strength required for the substrate in the film forming step and the subsequent step, and the surface smoothness is good. Examples of the resin used for the resin film include polyethylene terephthalate (PET), polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polyethersulfone, polysulfone, polyarylate, cyclic polyolefin, polyimide, and the like. The substrate 11 is preferably 10 μm or more and 200 μm or less in order to reduce the thickness of the transparent conductive laminate 10 and maintain the flexibility of the substrate 11. The same applies to the substrates 11a and 11b.

  The substrate 11 may contain various additives and stabilizers. Examples of the additives and stabilizers include antistatic agents, plasticizers, lubricants, and easy adhesives. The substrate 11 is subjected to corona treatment, low-temperature plasma treatment, ion bombardment treatment, chemical treatment, or the like as pretreatment in order to improve adhesion between the layer laminated on the substrate 11 and the substrate 11. Also good. The same applies to the substrates 11a and 11b.

  The transparent electrode layer 12a is formed of a resin, which will be described later, laminated on the substrate 11, and has a plurality of conductive regions 13a and a plurality of non-conductive regions 14a. Similarly, the transparent electrode layer 12b has a plurality of conductive regions 13b and a plurality of non-conductive regions 14b. The conductive regions 13a and 13b are an example of electrode portions.

  The conductive regions 13a and 13b are formed by including a fibrous metal such as a metal nanowire in the resin forming the transparent electrode layers 12a and 12b. For example, gold, silver, copper, cobalt, or the like is used as the fibrous metal. The fibrous metals contained in the conductive regions 13a and 13b are in contact with each other in the conductive regions 13a and 13b, whereby the conductive regions 13a and 13b have conductivity. On the other hand, the non-conductive regions 14a and 14b do not contain or hardly contain a fibrous metal in the transparent electrode layers 12a and 12b.

  The transparent electrode layer 12a is formed, for example, in a pattern in which a plurality of conductive regions 13a extending in the X direction are arranged side by side in the Y direction perpendicular to the X direction. The non-conductive region 14a is a region between the plurality of conductive regions 13a and is insulated from each of the conductive regions 13a. The transparent electrode layer 12b facing the transparent electrode layer 12a is formed, for example, in a pattern in which a plurality of conductive regions 13b extending in the Y direction are arranged side by side in the X direction. The non-conductive region 14b is a region between the plurality of conductive regions 13b and is insulated from each of the conductive regions 13b. Each of the conductive regions 13a and 13b is formed in, for example, a mesh shape as shown in FIG. 4 or a belt shape as shown in FIG. Note that the cross-sectional views shown in each drawing show the conductive regions in the same direction on both surfaces of the substrate for convenience of showing the configuration of each conductive region and each non-conductive region.

  Each of the conductive regions 13a and 13b is connected to a circuit (not shown) that detects a change in capacitance formed in the conductive regions 13a and 13b by a change in current. When a human finger or the like approaches the conductive regions 13a and 13b, the capacitance changes. Based on the detection of the change in capacitance, the contact position of a human finger or the like is determined.

  The transparent electrode layer 12a includes a resin. Similarly, the transparent electrode layer 12b also contains a resin. By forming the transparent electrode layers 12a and 12b from resin, the detachment of the fibrous metal from the conductive regions 13a and 13b is suppressed, and the mechanical strength of the transparent conductive laminate 10 is improved. The fibrous metal is protected and durability is improved.

Although it does not specifically limit as resin which forms the transparent electrode layers 12a and 12b, Resin which has transparency, moderate hardness, and mechanical strength is preferable. As a specific example, it is preferable to use a photocurable resin such as a monomer or a crosslinkable oligomer having a trifunctional or higher functional acrylate that can be expected to be three-dimensionally crosslinked.
Examples of trifunctional or higher acrylate monomers include trimethylolpropane triacrylate, isocyanuric acid EO-modified triacrylate, pentaerythritol triacrylate, dipentaerythritol triacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol. Hexaacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol tetraacrylate, polyester acrylate, or the like is preferably used. In particular, any of isocyanuric acid EO-modified triacrylate and polyester acrylate is preferably used. These acrylate monomers may be used alone or in combination of two or more monomers. In addition to these tri- or higher functional acrylates, it is possible to use acrylic resins such as epoxy acrylates, urethane acrylates and polyol acrylates in combination.
As the crosslinkable oligomer, it is preferable to use an acrylic oligomer such as polyester (meth) acrylate, polyether (meth) acrylate, polyurethane (meth) acrylate, epoxy (meth) acrylate, or silicone (meth) acrylate. Specific examples include polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, bisphenol A type epoxy acrylate, polyurethane diacrylate, cresol novolac type epoxy (meth) acrylate, and the like.
An additive such as a polymerization initiator may be mixed in the resin forming the transparent electrode layers 12a and 12b.
When a photopolymerization initiator is added as a polymerization initiator, benzoin and its alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzylmethyl ketal are used as radical generating photopolymerization initiators, acetophenone 2,2-dimethoxy-2-phenylacetophenone, acetophenones such as 1-hydroxycyclohexyl phenyl ketone, anthraquinones such as methylanthraquinone, 2-ethylanthraquinone, 2-amylanthraquinone, thioxanthone, 2,4-diethylthioxanthone, 2 Thioxanthones such as 1,4-diisopropylthioxanthone, ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal, benzophenone, 4,4-bis Benzophenones such as chill aminobenzophenone, or, and azo compounds. These photopolymerization initiators may be used alone or as a mixture of two or more polymerization initiators. Further, these photopolymerization initiators are photoinitiators such as tertiary amines such as triethanolamine and methyldiethanolamine, and benzoic acid derivatives such as 2-dimethylaminoethylbenzoic acid and ethyl 4-dimethylaminobenzoate. Etc. can be used in combination.

  The thickness of the transparent electrode layers 12a and 12b is not particularly limited as long as the durability of the fibrous metal is maintained and the metal does not fall off. However, if the transparent electrode layers 12a and 12b are too thick, the metal is covered with a resin and the conductivity is lowered. For these reasons, the transparent electrode layers 12a and 12b preferably have a thickness of 30 nm to 150 nm.

  Further, the transparent conductive laminate 10 preferably has a heat shrinkage rate of 0.5% or less when left at 150 ° C. for 30 minutes. If the heat shrinkage rate is within the above range, the transparent conductive laminate 10 is prevented from shrinking due to heat applied in the manufacturing process. As a result, pattern displacement between the transparent electrode layer 12a and the transparent electrode layer 12b is suppressed.

  The transparent conductive laminate 10 may include other layers between the substrate 11 and the transparent electrode layer 12a, or between the substrate 11 and the transparent electrode layer 12b. Examples of the other layers include a layer for enhancing the adhesion between the substrate 11 and the transparent electrode layers 12a and 12b, a layer for reinforcing the mechanical strength of the transparent conductive laminate 10, and the like.

The plurality of conductive regions 13a and 13b formed in the transparent electrode layers 12a and 12b are each insulated. Each conductive region has two adjacent conductive regions that are adjacent to each other for 240 hours or more in a state where a voltage is applied to the adjacent two conductive regions in a high-temperature and high-humidity atmosphere (for example, temperature 60 ° C., humidity 90% RH). A state where insulation between regions is maintained is desirable. In order to evaluate this state, as shown in FIG. 6, it is possible to create the wiring 40a with silver paste or the like in the conductive regions 13a and 13b and connect it to a device 54 for applying a voltage. The insulation state of the two adjacent conductive regions 13a and 13b can be determined by measuring the value of the flowing current and converting it to a resistance value. It is also preferable to use a line insulation evaluation device or the like as a device for applying a voltage and measuring a current value or a resistance value every time in a high temperature and high humidity atmosphere. The reason why the insulation between the two adjacent conductive regions 13a and 13b is maintained for 240 hours or more is that, as a general guideline, the quality is maintained if there is no change for 240 hours or more in the environmental test of the electronic device. It is to be done. Further, as a state where insulation is maintained, the resistance value is preferably 10 ⁹ Ω or more.

  In addition, in a state where a voltage is applied to two adjacent conductive regions 13a and 13b in a high-temperature and high-humidity atmosphere, insulation is maintained for 240 hours or more. It depends on the state of the fibrous metal remaining in the non-conductive regions 14a and 14b. The conductive regions 13a and 13b and the non-conductive regions 14a and 14b are formed by an etching method or the like, and the conductive regions 13a and 13b exhibit conductivity when the fibrous metals are in contact with each other. On the other hand, even if the fibrous metal remains, the non-conductive regions 14a and 14b are not conductive unless the fibrous metal is cut and has a contact portion. However, even if the conductivity is not shown, if a large amount of fibrous metal remains in the non-conductive regions 14a and 14b, if a voltage is applied to the conductive regions 13a and 13b in a high-temperature and high-humidity atmosphere, the non-conductive regions 14a and 14b Since the fibrous metal remaining in the conductive regions 14a and 14b promotes the growth of the metal, migration easily occurs, current flows between the two adjacent conductive regions 13a and 13b, and the insulation resistance value decreases. Therefore, the non-conductive regions 14a and 14b are maintained so that the insulation between the two electrodes is maintained for 240 hours or more in a state where a voltage is applied to the two adjacent conductive regions 13a and 13b in a high-temperature and high-humidity atmosphere. It is desirable not to leave the fibrous metal on the surface, and it is desirable to carry out etching conditions that satisfy this condition. The remaining state of the fibrous metal can be confirmed with an optical microscope or the like.

  In order to prevent the fibrous metal from remaining in the non-conductive regions 14a and 14b, the thickness of the transparent electrode layers 12a and 12b is desirably 30 nm or more and 150 nm or less. If it exceeds 150 nm, the progress of etching is slow, and even if the non-conductive regions 14a and 14b are electrically insulated, the amount of remaining fibrous metal increases. If it is thinner than 30 nm, the role of protecting the metal layer cannot be achieved, and the durability of the fibrous metal cannot be maintained as described above.

  In order to maintain insulation for 240 hours or more in a state where a voltage is applied to two adjacent conductive regions 13a and 13b in a high-temperature and high-humidity atmosphere, between the two adjacent conductive regions 13a and 13b. It is also possible to increase the distance. However, if the distance is increased, the size of the touch panel increases and the pattern becomes invisible. Therefore, the distance is preferably in the range of 50 μm to 500 μm.

  In order to evaluate a state where insulation is maintained for 240 hours or more in a state where a voltage is applied to two adjacent conductive regions 13a and 13b in a high-temperature and high-humidity atmosphere, the conductive regions 13a and 13b are protected with a protective material or the like. Covering with is also preferably performed. In an actual touch panel, the electrodes are covered with a cover layer, a display panel, etc., and are not exposed. In order to evaluate the state in a similar state, it is desirable to cover the electrode with a protective material or the like. Examples of the protective material include a method of applying a curable resin or bonding a film through an adhesive material.

  Further, as shown in FIG. 7, lead wirings 40a and 40b for connecting an IC circuit for driving as a touch panel are formed in the conductive regions 13a and 13b. Furthermore, a cover layer 50 made of glass or the like is laminated on the transparent electrode layer 12 a on the surface side of the substrate 11 through an adhesive layer 41 to constitute a touch panel 51. The surface of the cover layer 50 becomes a contact surface such as a human finger. Further, a display panel 52 such as a liquid crystal panel is laminated on the transparent electrode layer 12 b on the back side of the substrate 11, and a display device 53 is configured from the touch panel 51 and the display panel 52.

[Method for producing transparent conductive laminate]
With reference to FIGS. 8-15, the manufacturing method of the transparent conductive laminated body 10 shown in FIG. 1 as a typical example is demonstrated.

As shown in FIG. 8, first, a metal layer 16 a is formed on the surface of the substrate 11. The metal layer 16 a is formed by applying a solution in which a fibrous metal is dispersed to the substrate 11. The solvent for dispersing the fibrous metal is preferably water or an alcohol-based solvent, specifically, a highly hydrophilic solvent such as methanol, ethanol, or isopropanol. These solvents may be used alone or in combination of two or more solvents.
Examples of the method for forming the metal layer 16a include spin coating, roller coating, bar coating, dip coating, gravure coating, curtain coating, die coating, spray coating, doctor coating, and kneader coating. Known methods such as a coating method, a printing method such as a screen printing method, a spray printing method, an ink jet printing method, a relief printing method, an intaglio printing method, and a lithographic printing method are used.

Next, as shown in FIG. 9, a solution containing a resin constituent material for forming the transparent electrode layer 12a is applied on the metal layer 16a to form a transparent conductive layer 17a composed of the metal layer 16a and the resin. Is done. The solvent that dissolves the constituent material of the resin is not particularly limited as long as it is a solvent that dissolves the above-mentioned main component acrylate. Specific examples of the solvent include ethanol, isopropyl alcohol, isobutyl alcohol, benzene, toluene, xylene, acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, n-butyl acetate, isoamyl acetate, ethyl lactate, methyl cellosolve, and ethyl cellosolve. Butyl cellosolve, methyl cellosolve acetate, or propylene glycol monomethyl ether acetate. These solvents may be used alone or in combination of two or more solvents.
The solution containing the resin applied to the metal layer 16a penetrates into the gap between the fibrous metals included in the metal layer 16a. As the coating method, a known method similar to the method for forming the metal layer 16a exemplified above is used. The application method may be the same method as the formation method of the metal layer 16a, or may be a different method.

  As shown in FIG. 10, next, a metal layer 16 b is formed on the back surface of the substrate 11. The metal layer 16b is formed by the same method as the metal layer 16a. And the solution containing the constituent material of resin which forms the transparent electrode layer 12b is apply | coated on the metal layer 16b, and the transparent conductive layer 17b which consists of the metal layer 16b and resin is formed. The transparent conductive layer 17b is formed by the same method as the transparent conductive layer 17a. The metal layer 16a is an example of a first metal layer, and the metal layer 16b is an example of a second metal layer. The transparent conductive layer 17a is an example of a first transparent conductive layer, and the transparent conductive layer 17b is an example of a second transparent conductive layer.

  Next, patterning is performed to form conductive regions 13a and 13b and non-conductive regions 14a and 14b in the transparent conductive layers 17a and 17b. Any patterning method may be used as long as it can form a pattern such as wet etching by photolithography and dry etching by laser. As an example, a photolithography method is shown below.

  As shown in FIG. 11, next, a resist 18a is formed on the surface of the transparent conductive layer 17a on the front surface side of the substrate 11, and a resist 18b is formed on the surface of the transparent conductive layer 17b on the back surface side of the substrate 11. It is formed.

  As the resists 18a and 18b, negative resists or positive resists may be used. A known material is used for the resists 18a and 18b, and the resists 18a and 18b are formed by a known method.

  As shown in FIG. 12, next, a laminate in which the resists 18a and 18b are formed is disposed between the two light sources 21a and 21b that irradiate the resists 18a and 18b with light. On the surface side of the substrate 11, between the resist 18a and the light source 21a, a mask 19a having a pattern corresponding to the pattern of the conductive region 13a of the transparent electrode layer 12a and light of a specific wavelength are provided between the resist 18a and the light source 21a. Are arranged in this order. On the back side of the substrate 11, between the resist 18b and the light source 21b, a mask 19b having a pattern corresponding to the pattern of the conductive region 13b of the transparent electrode layer 12b and light of a specific wavelength are provided between the resist 18b and the light source 21b. Are arranged in this order.

  Then, the resist 18a is exposed to light from the light source 21a to expose the resist 18a, and the resist 18b is exposed to light from the light source 21b to the resist 18b. The exposure of the resist 18a and the exposure of the resist 18b may be performed sequentially or simultaneously. However, when performing simultaneously, it is necessary to insert a light-absorbing layer between one transparent electrode layer and the other transparent electrode layer so that the pattern of one transparent electrode layer does not transfer to the other transparent electrode layer There is. For the layer that absorbs light, the substrate 11 may have a light absorption function, or there is a method of inserting a light absorption layer between the substrate 11 and the transparent electrode layers 12a and 12b.

  Next, as shown in FIG. 13, when the resists 18a and 18b are of the negative type, the unexposed portions of the resists 18a and 18b are removed by the developer. Alternatively, when the resists 18a and 18b are positive, the exposed portions of the resists 18a and 18b are removed by the developer. Thereby, patterns corresponding to the masks 19a and 19b are formed on the resists 18a and 18b. That is, a pattern set as a pattern of the conductive regions 13a and 13b in the transparent electrode layers 12a and 12b is formed on the resists 18a and 18b.

As shown in FIG. 14, next, the exposed portion of the transparent conductive layer 17a is etched according to the pattern of the resist 18a, and the exposed portion of the transparent conductive layer 17b is etched according to the pattern of the resist 18b. As the etching method, a known method such as immersion of the laminate in acid or alkali is used. Thereby, in the transparent conductive layers 17a and 17b, in the portions not covered with the resists 18a and 18b, the metal layers 16a and 16b are removed by the corrosion of the fibrous metal, and the resin remains. As a result, in the transparent conductive layers 17a and 17b, the non-conductive regions 14a and 14b are formed in the portions not covered with the resists 18a and 18b, and the portions covered with the resists 18a and 18b are the conductive regions 13a and 13b. Become. As a result, the metal layer 16a included in the transparent conductive layer 17a is patterned to form the transparent electrode layer 12a. Further, the metal layer 16b included in the transparent conductive layer 17b is patterned to form the transparent electrode layer 12b.
As shown in FIG. 15, next, the resists 18a and 18b are removed. Thereby, the transparent conductive laminated body 10 is obtained.

  In the transparent conductive laminate 20 shown in FIG. 2, a metal layer 16a is formed on the surface of a substrate 11a, and a solution containing a constituent material of a resin for forming the transparent electrode layer 12a is applied to the metal layer 16a to apply the transparent conductive layer 17a. Is formed. Further, a metal layer 16b is formed on the surface of the substrate 11b, and a solution containing a resin constituent material for forming the transparent electrode layer 12b is applied to the metal layer 16b to form the transparent conductive layer 17b. The transparent electrode layers 12a and 12b are formed on one side of the substrates 11a and 11b through the same steps as those shown in FIGS. And the back surface side of the board | substrate 11a and the transparent electrode layer 12b are bonded together through the adhesion layer 23, and the transparent conductive laminated body 20 is manufactured. Examples of the resin used for the adhesive layer 23 include acrylic resins, silicone resins, and rubber resins. For the adhesive layer 23, it is preferable to use a resin excellent in cushioning properties and transparency.

  In the transparent conductive laminate 30 shown in FIG. 3, the metal layer 16a is formed on the surface of the substrate 11a, and the transparent conductive layer 17a is coated with a solution containing a resin constituent material that forms the transparent electrode layer 12a. Is formed. Further, a metal layer 16b is formed on the surface of the substrate 11b, and a solution containing a resin constituent material for forming the transparent electrode layer 12b is applied to the metal layer 16b to form the transparent conductive layer 17b. And the back surface of the board | substrate 11a and the back surface of the board | substrate 11b are bonded together by the adhesion layer 23. FIG. Thereafter, the transparent conductive laminate 30 is manufactured through the same steps as those shown in FIGS. Examples of the resin used for the adhesive layer 23 include acrylic resins, silicone resins, and rubber resins. For the adhesive layer 23, it is preferable to use a resin excellent in cushioning properties and transparency.

  Examples of the present invention are shown below, but the technical scope of the present invention is not limited to these Examples.

(Example)
A UV curable resin was applied to one side of a PET substrate (75 μm), and a metal layer made of a fibrous metal was formed thereon by a die coating method. Next, a solution containing an acrylic monomer as a main component was applied by a micro gravure coating method to a dry film thickness of 70 nm and cured by UV irradiation to obtain a transparent conductive layer. Similarly, a metal layer and a transparent conductive layer were formed on the opposite side of the PET substrate by the same method. Next, a negative resist is applied by a photolithography method, cured by UV irradiation, etched with hydrochloric acid (0.1%), stripped of the resist with a sodium hydroxide solution (1%), patterned, and strip-shaped. A plurality of conductive regions were created. Wiring was formed by screen printing using a conductive paste based on epoxy resin and silver in each band-shaped conductive region to obtain a transparent conductive laminate having a transparent electrode layer thickness of 70 nm. A voltage of 5 V is applied to the adjacent conductive region of the obtained transparent conductive laminate, and it is put in an environment of a temperature of 60 ° C. and a humidity of 90%, and the resistance value is measured for each time using a line insulation evaluation apparatus. Went. The measurement was performed up to 500 hours. Further, two transparent conductive laminates are bonded together via an adhesive layer, a glass cover material is bonded using an adhesive, an IC control circuit is connected to create a touch panel, and a temperature of 60 ° C. and a humidity of 90 %, The operation test was continued and the touch position and the detection position were confirmed every time.

(Comparative example)
A UV curable resin was applied on one side on a PET substrate (75 μm), and a metal layer made of a fibrous metal was formed thereon by a die coating method. Next, a solution containing an acrylic monomer as a main component was applied by a micro gravure coating method to a dry film thickness of 300 nm and cured by UV irradiation to obtain a transparent conductive layer. Similarly, a metal layer and a transparent conductive layer were formed on the opposite side of the PET substrate by the same method. Next, a negative resist was applied by photolithography, and after curing by UV irradiation, the resist was peeled off by etching with hydrochloric acid (0.1%) and sodium hydroxide solution (1%) for patterning. A conductive paste based on an epoxy resin and silver was used to form a wiring by screen printing, thereby obtaining a transparent conductive laminate having a transparent electrode layer thickness of 300 nm. A voltage of 5 V was applied to adjacent conductive regions of the obtained transparent conductive laminate, and the resultant was put in an environment of a temperature of 60 ° C. and a humidity of 90%, and the resistance value was measured for each time. The measurement was performed up to 500 hours. Further, the two transparent conductive laminates are bonded together via an adhesive layer, and a glass cover material is bonded using an adhesive, and an IC control circuit is connected to create a touch panel. The operation test was continuously performed in a 90% humidity environment, and the touch position and the detection position were confirmed every time.

Table 1 shows the measurement results in Examples and Comparative Examples.
In the example, after 240 hours had passed since the temperature was 60 ° C. and the humidity was 90%, the resistance value of the adjacent conductive region was 10 ⁹ Ω or more and insulation was maintained. Further, even after 500 hours, the resistance value did not decrease and insulation was maintained. On the other hand, in the comparative example, the resistance value between the adjacent conductive regions gradually decreases after being put in the environment of temperature 60 ° C. and humidity 90%, and becomes 5.0 × 10 ⁴ Ω after 150 hours, and further time passes. And the resistance value decreased. Moreover, when the board | substrate of the comparative example was observed with the optical microscope, the metal dendritic material existed in the nonelectroconductive area | region. In addition, when a touch panel was created using the transparent conductive laminates of the example and the comparative example, the touch was recognized normally in the example, but the comparative example was detected as being touched at a different location from the touched location, and the touch was detected. It became misrecognition. From the above results, it was confirmed that the transparent conductive laminate according to the example did not malfunction even when it was put in a high temperature and high humidity for a long time.

  The technology of the present disclosure can be used for a transparent conductive laminate and a touch panel including the transparent conductive laminate.

10, 20, 30 Transparent conductive laminate 11, 11a, 11b Substrate (transparent substrate)
12a, 12b Transparent electrode layer 13a, 13b Conductive region 14a, 14b Non-conductive region 16a, 16b Metal layer 17a, 17b Transparent conductive layer 18a, 18b Resist 19a, 19b Mask 20a, 20b Optical filter 21a, 21b Light source 23 Adhesive layer 40a, 40b Wiring 41 Adhesive layer 50 Cover layer 51 Touch panel 52 Display panel 53 Display device 54 Voltage application device

Claims (3)

A transparent substrate;
Laminated on one or both surfaces of the transparent substrate, comprising a transparent electrode layer containing a resin,
The transparent electrode layer includes a plurality of conductive regions having a fibrous metal and a non-conductive region,
A transparent conductive laminate in which an electrical resistance value between the conductive regions adjacent to each other through the non-conductive region is 10 ⁹ Ω or more after 240 hours have passed after being put in an atmosphere of a temperature of 60 ° C. and a humidity of 90% body.   The transparent conductive laminate according to claim 1, wherein the transparent electrode layer has a thickness of 30 nm to 150 nm.   A touch panel provided with the transparent conductive laminated body of Claim 1 or 2.

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