JP2013054599A - Conductor, conductive sheet and touch panel - Google Patents

Abstract

A conductor containing a polythiophene-based conductive agent, which is excellent in durability under high-temperature and low-humidity conditions and has little decrease in conductivity, and a conductive sheet provided with a conductive layer made of the conductor, It is an object to provide a touch panel including the conductive sheet.
A nitrogen-containing silane containing at least a polythiophene-based conductive agent and a coupling agent component, wherein the coupling agent component has, for example, one or more of a ureido group, a ureylene group and an isocyanurate group. A conductor comprising at least one of a coupling agent and its reactant. Moreover, the conductive sheet 10 which has the conductive layer 12 which consists of the said conductor on the at least single side | surface of the insulating layer 11, and a touch panel provided with this.
[Selection] Figure 1

Description

  The present invention relates to a touch panel used as a position input device, a conductor suitably used for the touch panel, and a conductive sheet.

  A touch panel is an electronic component that functions as a position input device, is combined with a display device such as a liquid crystal panel, and is widely used in mobile phones, portable game machines, and the like. When the operator points to a specific position of the touch panel with a hand or an input pen based on the screen display, the device senses the information on the specific position and can perform an appropriate operation desired by the operator. Interface.

  In the touch panel, there are, for example, a resistance film type and a capacitance method as a method of detecting the position to be pointed, but the capacitance method has been rapidly expanded mainly in mobile devices such as mobile phones. As a typical detection method of the electrostatic capacity method, there are two methods, namely, a surface type for analog detection and a projection type by an integrated detection method using patterned electrodes. In addition, a number of proposals have been made for the projection type configuration for each method and manufacturer, but as a projection type that has recently increased rapidly, an insulating layer sandwiched between conductive layers and a protective plate for the surface can be used by using glass or a resin plate. Many of them have been given durability. In the future, it is expected that by making these various resin films, the movement to reduce costs and make them flexible will expand.

As the conductive layer that is the key to the touch panel, ITO (indium oxide doped with tin oxide) layer, which is formed by dry methods such as sputtering and vapor deposition, is the most frequently used because it can achieve both conductivity and transparency. ing.
However, when the touch panel structural material is made flexible by using a film as described above, the ITO layer has low flexibility, and thus durability may be significantly reduced.
Therefore, a layer using an organic conductive polymer has been studied as a conductive layer having excellent flexibility. For example, a polythiophene conductive agent is known as the organic conductive polymer. For example, Patent Document 1 discloses a conductive film including a conductive layer formed from a coating composition containing a polythiophene-based conductive agent and a coupling agent having an epoxy group.

Japanese Patent No. 4700391

However, the conductive layer formed from the composition containing the polythiophene-based conductive agent is excellent in durability under high temperature and high humidity conditions such as 85 ° C. and 80 RH%, for example, and the decrease in conductivity is suppressed. However, under high temperature and low humidity conditions such as in a thermostatic chamber at 80 ° C., for example, the durability is poor and a decrease in conductivity may be observed.
The condition in the constant temperature chamber at 80 ° C. generally corresponds to a non-humidifying condition at 80 ° C. called “80 ° C. Dry”.

  The present invention has been made in view of the above circumstances, and is a conductor including a polythiophene-based conductive agent, which is excellent in durability under high-temperature and low-humidity conditions and has a low conductivity decrease, and the conductor. An object is to provide a conductive sheet including a conductive layer and a touch panel including the conductive sheet.

As a result of intensive studies by the present inventor, it has been confirmed that the durability of a conductor containing a polythiophene-based conductive agent under high temperature and low humidity conditions is related to the type of silane coupling agent component contained in the conductor as a modifier. The headline and the present invention were completed.
The conductor of the present invention contains at least a polythiophene-based conductive agent and a coupling agent component, and the coupling agent component contains at least one of a nitrogen-containing silane coupling agent and a reaction product thereof. It is characterized by.
The nitrogen-containing silane coupling agent preferably has one or more of a ureido group, a ureylene group and an isocyanurate group.
The conductive sheet of the present invention has a conductive layer made of the conductor of the present invention on at least one surface of an insulating layer.
The touch panel of the present invention comprises the conductive sheet of the present invention.
The conductive sheet constituting the touch panel preferably has the patterned conductive layer on both sides of the insulating layer.

  According to the present invention, a conductive material comprising a polythiophene-based conductive agent, having excellent durability under high temperature and low humidity conditions, and having a low conductivity decrease, and a conductive material comprising a conductive layer made of the conductive material A sheet and a touch panel provided with the conductive sheet can be provided.

It is sectional drawing which shows an example of the electroconductive sheet of this invention. It is sectional drawing which shows an example of the electroconductive laminated body provided with the electroconductive sheet of FIG. It is sectional drawing explaining the manufacturing method of the electroconductive laminated body of FIG. It is sectional drawing which shows another example of the electroconductive laminated body provided with the electroconductive sheet of FIG. It is sectional drawing which shows an example of the liquid crystal module which comprises the touch panel of this invention. It is sectional drawing which shows the touchscreen (touchscreen module) manufactured in the Example.

Hereinafter, the present invention will be described in detail.
<Conductor (conductive layer)>
The conductor of the present invention is a conductor containing at least a polythiophene-based conductive agent and a coupling agent component. The coupling agent component is included as one component of the binder component as described later. And a coupling agent component contains at least 1 sort (s) of a nitrogen-containing silane coupling agent and its reaction material.
Hereinafter, as a specific form of the conductor, a layered conductor provided on an insulating layer or the like, that is, a conductive layer will be exemplified and described in detail.

[Polythiophene-based conductive agent]
Polythiophene-based conductive agent is a π-conjugated organic conductive polymer that develops conductivity with a main chain in which double bonds and single bonds are arranged alternately. Sex can be achieved.
As a polythiophene-based conductive agent, a polymer of 3-hexylthiophene (hereinafter sometimes abbreviated as 3HT) (hereinafter sometimes abbreviated as P3HT), a derivative thereof, 3,4-ethylenedioxythiophene (hereinafter referred to as P3HT). EDOT) polymer (hereinafter sometimes abbreviated as PEDOT) and one or more selected from the group consisting of derivatives thereof are preferably used. Derivatives such as self-doped polythiophene having a sulfonic acid group in the main chain and organic solvent-dispersed PEDOT copolymerized with a flexible polymer such as polyethylene glycol can also be used. Depending on the case, it is appropriately selected.

  As a method for forming a conductive layer containing a polythiophene-based conductive agent, for example, a method of applying a coating liquid for forming a conductive layer or printing ink for forming a conductive layer on an insulating layer is employed. There are many cases. When such a method is employed, a polystyrene sulfonic acid (hereinafter referred to as a polythiophene-based conductive agent) that functions not only as a dopant for enhancing conductivity but also as a dispersant for PEDOT that becomes fine particles in water by polymerization. , And may be abbreviated as PSS) in the presence of an aqueous dispersion obtained by polymerizing EDOT (hereinafter abbreviated as PEDOT-PSS), or polyvinyl sulfonic acid (hereinafter abbreviated as PVS) instead of PSS. It is preferable to prepare a coating liquid or ink for forming a conductive layer using PEDOT-PVS or the like.

  When using the above-mentioned PEDOT or a derivative thereof, a high-boiling-point solvent whose conductivity improving effect has been confirmed is added as a secondary dopant to the coating liquid or ink for forming the conductive layer, thereby forming the conductive film formed thereby. A secondary dopant may be present in the layer. Examples of such secondary dopants include high-boiling solvents such as polyethylene glycol, methylformamide, dimethyl sulfoxide, and N-methylpyrrolidone. In that case, the addition amount of the high boiling point solvent in the coating liquid or ink for forming the conductive layer is preferably 10 to 500 parts by mass, and more preferably 100 to 300 parts by mass with respect to 100 parts by mass of the polythiophene-based conductive agent. If the addition amount of the high boiling point solvent is too small, the effect as the secondary dopant cannot be sufficiently obtained, and if the addition amount of the high boiling point solvent is too large, the residual amount of the high boiling point solvent to the dry coating film increases. There is concern about bleeding.

  The conductive layer may further contain another conductive agent as long as the performance of the polythiophene-based conductive agent that is an essential component as a conductive substance is not impaired. Such a conductive agent is preferably used as long as it does not interfere with coating or printing when added to a coating solution or ink for forming a conductive layer. Examples of such conductive agents include metal compounds such as silver and copper (fine particles, wires, pastes or solubilized salts), metal oxide fine particles such as ITO and ATO, organic conductive polymers such as polyaniline, and conductive properties. A carbon nanotube etc. are mentioned and 1 or more types can be used.

  The content of the conductive agent in the conductive layer (the total amount of the polythiophene-based conductive agent and other conductive agents used as necessary) is preferably as high as possible. It is 90 mass%, More preferably, it is 30-70 mass%. Moreover, it is preferable that the ratio of the polythiophene-based conductive agent in the total conductive agent is preferably 50% by mass or more because a conductive layer excellent in flexibility can be formed.

[Binder component]
The binder component is used for improving the film formability of the conductive layer. The coupling agent component is included in the conductive layer as one of the binder components.
In addition to the coupling agent component, the binder component includes at least a resin component.

(Resin component)
Examples of the resin component include acrylic resins, styrene resins, polyester resins, alkyd resins, urethane resins, amide resins, modified resins thereof, and copolymers thereof, and one or more of these resins. Can be used.
In addition, the resin component is not limited to the resin thus polymerized, but includes a monomer or an oligomer that is polymerized to become a polymer, and a polymerization initiator or a crosslinking agent that activates these with light or heat. A polymerizable composition such as a mixture with a film component can also be used.

  Examples of the monomer or oligomer include polyester (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, and the like, and one or more of these can be used. Specifically, as the radical polymerization system, monofunctional ethyl carbitol (meth) acrylate, phenol ethylene oxide modified (meth) acrylate, nonylphenol ethylene oxide modified (meth) acrylate, ethoxydiethylene glycol acrylate, acryloylmorpholine, isobornyl (meta) ) Acrylate, N-vinyl pyrrolidone, bifunctional hexanediol di (meth) acrylate, hexanediol ethylene oxide modified diacrylate, neopentyl glycol polyethylene oxide modified di (meth) acrylate, tetraethylene glycol di (meth) acrylate, tri Propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, bisphenol A ethylene oxide Iodine-modified di (meth) acrylate, polyethylene glycol di (meth) acrylate, tri- or more-functional trimethylolpropane tri (meth) acrylate, trimethylolpropane ethylene oxide-modified tri (meth) acrylate, glycerin propoxytri (meth) acrylate, di Examples of cationic polymerization systems such as pentaerythritol hexaacrylate and ditrimethylolpropane tetraacrylate include, but are not limited to, epoxy compounds such as glycidyl ether compounds and alicyclic epoxy compounds, oxetane compounds, and vinyl ether compounds. .

Known polymerization initiators can be used.
As the crosslinking agent, those capable of imparting solvent resistance to the conductive layer are used. Among the above monomers and oligomers, trifunctional or higher functional monomers and oligomers; known crosslinking agents such as epoxy-based, isocyanate-based, and melamine-based materials are used. it can. However, the melamine-based crosslinking agent tends to cause a decrease in the transparency of the conductive layer, and its use requires caution.

The type of the resin component is appropriately selected depending on the type and properties of the polythiophene-based conductive agent, the type and configuration of the insulating layer on which the conductive layer is provided, but it has no hygroscopicity, high acid resistance, and coating suitability. A polyester-based resin is preferable because it is excellent.
In addition, the amount of the resin component in the conductive layer is preferably smaller from the viewpoint of conductivity by the polythiophene-based conductive agent, but if it is too small, the film formability of the conductive layer is lowered. From these viewpoints, the amount of the resin component is preferably 500 parts by mass or less and more preferably 300 parts by mass or less with respect to 100 parts by mass of the polythiophene-based conductive agent.

  If the conductive layer constitutes a touch panel and the conductive layer needs to be patterned according to the touch panel type, patterning can be performed with a photomask using a photo-curable photosensitive binder. You may be able to do it. When the conductive layer is patterned by printing, the amount of the resin component used and the molecular weight that greatly affects the viscosity may be appropriately adjusted in order to adjust the ink viscosity to be suitable for various printing methods.

(Coupling agent component)
The coupling agent component is one component of the binder component for the purpose of improving the film formability and hardness of the conductive layer itself, and improving the adhesion between the conductive layer and other layers laminated on the conductive layer. As described above, it is contained in the conductive layer together with the resin component described above.
For example, when the conductive layer is formed on the insulating layer, the contact surface of the insulating layer with the conductive layer is made of a hard coat layer containing an Si component, or the case is made of an easily adhesive layer made of a PET film. In particular, the effect of improving the adhesion between the conductive layer and the insulating layer due to the coupling agent component can be expected.

  As such a coupling agent component, there are a silane coupling agent which is an organosilicon compound having an organic functional group and an alkoxyl group in the molecule, and a reaction product thereof. The conductive layer of this example contains at least one of a nitrogen-containing silane coupling agent and a reaction product thereof as a coupling agent component.

  As a nitrogen-containing silane coupling agent, a ureido group (the following formula (1)), a ureylene group (the following formula (2)), an isocyanurate group (the following formula (3)), an isocyanate group (the following) A silane coupling agent containing at least one of the formula (4)) and amino group (the following formula (5)) is preferable.

式（５）中、Ｒ^３およびＲ^４は、水素原子または一価の炭化水素基である。

In formula (5), R ³ and R ⁴ are a hydrogen atom or a monovalent hydrocarbon group.

  Examples of the silane coupling agent containing a ureido group include a compound represented by the following formula (6). The ureido group which is a weakly basic group is preferable because it hardly causes aggregation due to shock when mixed with an acidic polythiophene conductive agent.

In Formula (6), R ¹ is an unsubstituted or substituted monovalent hydrocarbon group, and R ² is a hydrogen atom, a methyl group, or an ethyl group.
Examples of R ¹ include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a neopentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group. Alkyl groups such as dodecyl group; cycloalkyl groups such as cyclopentyl group, cyclohexyl group and cycloheptyl group; vinyl group, allyl group, propenyl group, isopropenyl group, butenyl group, isobutenyl group, hexenyl group, cyclohexenyl group, etc. An alkenyl group; an aryl group such as a phenyl group, a tolyl group, a xylyl group, a naphthyl group, and a biphenylyl group; an aralkyl group such as a benzyl group, a phenylethyl group, a phenylpropyl group, and a methylbenzyl group; Some or all of the hydrogen atoms are fluorine, chlorine, Groups substituted with halogen atoms such as bromine, cyano groups, etc., for example, chloromethyl group, 2-bromoethyl group, 3-chloropropyl group, 3,3,3-trifluoropropyl group, chlorophenyl group, fluorophenyl group, A cyanoethyl group, 3,3,4,4,5,5,6,6,6-nonafluorohexyl group, etc. are mentioned. Particularly preferred groups are a methyl group and an ethyl group.
Moreover, in Formula (6), a is an integer of 0-2. n is an integer of 1-6, preferably an integer of 3-6.

  Specific examples of the compound represented by the formula (6) include 3-ureidopropyltriethoxysilane (the following formula (7)).

As commercial products of 3-ureidopropyltriethoxysilane, as a 50% methanol solution, “KBE-585 (product name)” manufactured by Shin-Etsu Chemical Co., Ltd., “Silquest A” manufactured by Momentive Performance Materials Japan LLC. -1160 (product name) ”,“ Dynasylan 2201 EQ (product name) ”manufactured by Evonik Degussa Japan.
Moreover, the silane coupling agent containing a ureido group can be manufactured by the method as described in patent 3522902, for example.

Examples of the silane coupling agent containing a ureylene group include 1- [3- (triethoxy) propyl] -3-propylurea (the following formula (8)).
Examples of the silane coupling agent containing an isocyanurate group include tris- (3-trimethoxysilylpropyl) isocyanurate (the following formula (9)). As a commercial product of this silane coupling agent, there is “X-12-965 (product name)” manufactured by Shin-Etsu Chemical Co., Ltd.

  Examples of the silane coupling agent containing an isocyanate group include 3-isocyanatopropyltriethoxysilane. As a commercial product of this silane coupling agent, “KBE-9007 (product name)” manufactured by Shin-Etsu Chemical Co., Ltd. is available.

  The “reaction product of the nitrogen-containing silane coupling agent” is mainly generated in the step of forming the conductive layer, and is a nitrogen-containing silane coupling added to the coating liquid or ink for forming the conductive layer. Reactant generated by reaction of the agent with other components contained in the conductive layer, and reaction product generated by reaction of the nitrogen-containing silane coupling agent added to the coating liquid or ink for forming the conductive layer At least one of them. That is, by adding a nitrogen-containing silane coupling agent to these coating solutions or inks, at least one of the nitrogen-containing silane coupling agent and its reaction product is contained in the formed conductive layer. Will be included.

  As described above, the conductive layer containing the nitrogen-containing silane coupling agent and at least one of the reactants as a coupling component is excellent in durability under high-temperature and low-humidity conditions and has a small decrease in conductivity. The reason for this is not necessarily clear, but it is presumed that there is an influence of the electron withdrawing property of nitrogen atoms contained in the nitrogen-containing silane coupling agent and its reaction product.

  Further, as the nitrogen-containing silane coupling agent, it is preferable to use a silane coupling agent having low reactivity such as a silane coupling agent containing at least one of a ureido group, a ureylene group and an isocyanurate group. When these are used, the durability of the conductive layer under high temperature and low humidity conditions is more excellent. Although the reason for this is not necessarily clear, the ureido group, ureylene group and isocyanurate group are non-reactive polar organic groups, and the silane coupling agent containing these functional groups has hydrogen bonds based on these functional groups. The modification effect is expressed by secondary interaction such as. Therefore, when the conductive layer contains a silane coupling agent containing at least one kind of ureido group, ureylene group and isocyanurate group or a reaction product thereof, the polythiophene-based conductive agent, resin component, etc. In addition, it is estimated that hydrogen bonding occurs. When the conductive layer in which such a hydrogen bond exists is placed under a high temperature and low humidity condition, the hydrogen bond absorbs thermal energy and the buffering action such as breaking or recombining the hydrogen bond. Therefore, it is considered that the adverse effect of heat on the polythiophene-based conductive agent is avoided, and the decrease in conductivity is suppressed.

  On the other hand, when a silane coupling agent containing at least one functional group having a high reactivity such as an isocyanate group or an amino group is used as the nitrogen-containing silane coupling agent, the above buffering effect is exhibited. It can be guessed that it is difficult. Therefore, a silane coupling agent which does not have a highly reactive functional group such as an isocyanate group or an amino group and contains at least one of a ureido group, a ureylene group and an isocyanurate group is more preferably used, and more preferably It is a silane coupling agent which does not have a highly reactive functional group such as an isocyanate group or an amino group and contains a ureido group.

The amount of at least one of the nitrogen-containing silane coupling agent and the reaction product in the conductive layer varies depending on the type and amount of the resin component, but with respect to 100 parts by mass of the polythiophene-based conductive agent. 10-500 mass parts is preferable, and 50-300 mass parts is more preferable. When it is at least the lower limit of this range, the conductive layer can be sufficiently prevented from lowering in conductivity under high temperature and low humidity conditions. On the other hand, when the content is not more than the upper limit of this range, a decrease in conductivity of the conductive layer due to a large content of the nitrogen-containing silane coupling agent and its reaction product is suppressed. However, if the addition amount of the strongly basic nitrogen-containing silane coupling agent is too large, the pH becomes too high, and the conductive performance of the polythiophene-based conductive agent may not be sufficiently exhibited, which is not preferable.
The amount of the nitrogen-containing silane coupling agent with respect to 100 parts by mass of the polythiophene-based conductive agent in the coating liquid or ink for forming the conductive layer, and the nitrogen-containing silane coupling agent with respect to 100 parts by mass of the polythiophene-based conductive agent in the conductive layer; The amount of the reaction product.

The conductive layer may contain a plurality of the above-mentioned nitrogen-containing silane coupling agents and their reactants as coupling agent components. Moreover, one or more types of coupling agents other than nitrogen-containing and its reaction material may be contained.
Examples of other coupling agents include silane coupling agents such as epoxy, vinyl, methacrylic, acrylic, mercapto, and sulfide. The amount of these other coupling agents is preferably 200 parts by mass or less with respect to 100 parts by mass of the nitrogen-containing silane coupling agent as the amount added to the coating liquid or ink for forming the conductive layer. If it is such a range, while the inhibitory effect of the electroconductivity fall under high-temperature, low-humidity conditions by a nitrogen-containing silane coupling agent or its reaction material will be fully acquired, the combined use effect of another coupling agent will also be acquired. For example, when an epoxy-based silane coupling agent is used in combination, the effect of suppressing the decrease in conductivity under high temperature and high humidity conditions can also be obtained.

[Other ingredients]
In addition to the polythiophene-based conductive agent; the binder component including the coupling agent component; an antioxidant, a heat stabilizer, an ultraviolet absorber, a metal corrosion inhibitor, pH, as long as the conductive performance is not significantly impaired. Additives such as regulators, organic particles, inorganic particles, pigments, dyes, antistatic agents, nucleating agents, and coating aids such as wetting agents and antifoaming agents may be included as appropriate.
Wetting agents and antifoaming agents are effective in preventing defects in the conductive layer.For example, silicone-based, long-chain alkyl-based, fluorine-based surfactants are used, but when fluorine-based surfactants are used, In the case where an insulating layer is present adjacent to the conductive layer, the adhesion durability between the conductive layer and the insulating layer is likely to decrease. Therefore, silicone type and long chain alkyl type are preferably used.
In addition to mixing these surfactant components as additives, they may be integrated into the resin component by copolymerization or the like. When the contact angle of the conductive layer is adjusted to 50 degrees or more and 100 degrees or less, more preferably 60 degrees or more and 90 degrees or less by blending these components, the adhesion durability between the conductive layer and the insulating layer is improved when the conductive layer and the insulating layer are adjacent to each other. It is easy to obtain a conductive layer free from defects while maintaining.

  Next, the conductive sheet of the present invention provided with the above conductive layer on at least one surface of the insulating layer will be described in detail.

<Conductive sheet>
FIG. 1 is a cross-sectional view showing an example of the conductive sheet of the present invention. On one side of the insulating layer 11, a polythiophene-based conductive agent, at least one of a nitrogen-containing silane coupling agent and its reaction product, A conductive layer 12 made of a conductor containing Note that although FIG. 1 illustrates a mode in which a conductive layer is provided on only one surface of an insulating layer, a conductive layer may be provided on both surfaces of the insulating layer. Further, the cross-sectional view of FIG. 1 mainly shows a layer structure, and there are places where dimensions and thickness are emphasized as appropriate, and are not shown accurately.

[Conductive layer]
The conductive layer 12 may be a uniform layer formed on the insulating layer 11 with a substantially uniform thickness, which is used for, for example, an analog resistive film type touch panel or the like, for example, a projected capacitive touch panel A conductive layer having a regular pattern formed for position detection may be used. The regular pattern may be formed by a method in which the conductive layer 12 is partially provided on the insulating layer 11 in advance by various printing methods or the like, or the coating liquid for forming the conductive layer is uniform. It may be formed by removing a part thereof after application by wet etching using an etching solution or dry etching using a laser beam. Even in the case of a uniform layer, a part of the conductive layer 12 may be patterned in order to form an extraction electrode or the like depending on the configuration of the touch panel.

  The conductive layer 12 is preferably highly transparent for the purpose of use in a touch panel or the like. However, since the polythiophene-based conductive agent is a colored substance, the transparency of the conductive layer 12 depends on the content of the polythiophene-based conductive agent. It is greatly affected. The transparency of the conductive layer 12 is preferably 70% or more, more preferably 88% or more, as the total light transmittance (JIS K7105) of the conductive sheet 10 composed of the conductive layer 12 and the insulating layer 11. . Except for the case where light diffusivity is intentionally required, the haze (JIS K7105) of the conductive sheet 10 is preferably 5% or less, more preferably 2% or less.

The thickness of the conductive layer 12 varies greatly depending on the use of the conductive sheet 10 and the composition and properties of the conductive agent, and thus cannot be defined unconditionally, but the dry film thickness is 0.01 to 1 μm. More preferably, it is 0.02-0.08 micrometer. When the dry film thickness is not less than the lower limit of the above range, it is easy to ensure the uniformity of conductivity, and when it is not more than the upper limit, there is no problem of efficiency reduction and cost increase.
The conductivity of the conductive layer 12 is preferably a surface resistance of 10 ⁵ Ω / sq or less, more preferably 10 ³ Ω / sq or less, in order to obtain an electrode plate for a touch panel. The surface resistance can be adjusted by the composition of the conductive agent in the coating liquid or ink for forming the conductive layer, the coating amount, and the like.

  In addition, the extraction electrode can be connected to the surface of the conductive layer 12 or to the conductive layer 12, and may be formed of, for example, a highly conductive silver paste, or a metal material such as aluminum or molybdenum depending on the use situation. . As the formation method, a known method such as printing of paste or sputtering can be used as appropriate.

[Insulation layer]
The insulating layer 11 may be composed only of a sheet-like insulating base material made of a glass substrate, a resin film, a resin plate, or the like, or may be provided on the insulating base material and the surface thereof as necessary. It may be comprised from the layer of this. The insulating layer 11 is preferably formed to be bendable from the viewpoint of making the conductive sheet 10 flexible. Further, as the insulating layer 11, for example, a polarizing plate used in a liquid crystal module may be used.

(Insulating substrate)
Resin film constituting the insulating substrate and resin of the resin plate include polyethylene terephthalate, polyethylene naphthalate, polypropylene terephthalate, polybutylene terephthalate, polypropylene naphthalate, polyethylene, polypropylene, cellophane, diacetylcellulose, triacetylcellulose, cycloolefin Polymer, acetylcellulose butyrate, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl acetate copolymer, polystyrene, polycarbonate, polymethylpentene, polysulfone, polyetheretherketone, polyethersulfone, polyetherimide, polyimide , Fluororesin, polyamide, (meth) acrylic resin, copolymer of methyl methacrylate and styrene, etc. These may be a mixture thereof.

  Among them, as an insulating base material, from the viewpoint of transparency, weather resistance, solvent resistance, rigidity, cost, etc., a biaxially stretched film of polyethylene terephthalate, a glass substrate, a cycloolefin polymer, or a polycarbonate with good transparency, etc. From the viewpoint of flexibility, a sheet of polyethylene terephthalate biaxially stretched film, cycloolefin polymer, or polycarbonate having good transparency is preferable. Moreover, it is preferable at the point of a flexibility that the thickness of these insulating base materials is 10-200 micrometers.

Various additives may be contained in the insulating base material. Examples of the additive include antioxidants, heat stabilizers, ultraviolet absorbers, organic particles, inorganic particles, pigments, dyes, antistatic agents, nucleating agents, and coupling agents. Although these additives are used as needed, when using the conductive sheet 10 for a touch panel, it is preferable to select an additive that does not hinder the transparency of the conductive sheet 10.
The surface of the insulating base material may be subjected to surface oxidation treatment such as sand blast treatment or solvent treatment, corona discharge treatment, corona discharge treatment, chromic acid treatment, flame treatment, hot air treatment, ozone / ultraviolet irradiation treatment, etc. Good.

(Other layers constituting the insulating layer)
As a layer provided on the surface of the insulating base as necessary, for example, an interference fringe countermeasure layer, an optical adjustment layer such as a diffusion preparation layer to which various diffusing agents are added, and the adhesion with the conductive layer 12, Examples thereof include an anchor layer to which a reactive substance such as isocyanate is added. In addition, for patterning of the conductive layer 12 provided on the insulating base material, a foaming release layer may be provided on the insulating base material that can be peeled only at a location irradiated with the active energy ray.
In addition, when the surface of the insulating base material is exposed or for the purpose of suppressing surface scratches generated on the insulating base material during the process, the surface is mainly composed of a resin component and contains a hard component. A hard coat layer may be provided.

The resin component that is the main component of the hard coat layer is preferably an acrylic polymer that is a polymer of a monomer or oligomer having a polymerizable unsaturated group.
The monomer or oligomer having a polymerizable unsaturated group is preferably a polyfunctional (meth) acrylate, such as dipropylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, or tripropylene. Glycol di (meth) acrylate, polyethylene glycol (mass average molecular weight 600) di (meth) acrylate, propylene oxide modified neopentyl glycol di (meth) acrylate, modified bisphenol A di (meth) acrylate, tricyclodecane dimethanol di (meth) ) Acrylate, polyethylene glycol (mass average molecular weight 400) bifunctional (meth) acrylate such as di (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) ) Acrylate, trimethylolpropane ethoxytri (meth) acrylate, polyether tri (meth) acrylate, trifunctional (meth) acrylate such as glycerol propoxytri (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol ethoxytetra ( 4 or more functional groups such as (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, propionic acid-modified dipentaerythritol penta (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, etc. (Meth) acrylate is mentioned. One or more kinds of these polyfunctional (meth) acrylates can be used.
In order to make the pencil hardness of the hard coat layer 3H or higher, it is more preferable to select a tetrafunctional or higher (meth) acrylate.
The monomer or oligomer having a polymerizable unsaturated group may be thermosetting or active energy ray curable.

As the hard component, reactive inorganic oxide particles and / or reactive organic particles are used. When reactive inorganic oxide particles and / or reactive organic particles are used, antifouling properties, fingerprint adhesion prevention properties, antistatic properties and the like can be imparted.
The reactive inorganic oxide particles are inorganic oxide particles treated with a coupling agent, and the reactive organic particles are organic particles treated with a coupling agent. By treating the inorganic oxide particles or the organic particles with a coupling agent, the bonding strength with the acrylic polymer that is a resin component can be increased. As a result, surface hardness and scratch resistance can be improved, and dispersibility of inorganic oxide particles and organic particles can be improved.

As the inorganic oxide particles, those having high hardness are preferable, and for example, silicon dioxide particles, titanium dioxide particles, zirconium oxide particles, aluminum oxide particles and the like can be used.
Examples of organic particles that can be used include resin particles such as acrylic resin, polystyrene, polysiloxane, melamine resin, benzoguanamine resin, polytetrafluoroethylene, cellulose acetate, polycarbonate, and polyamide.
Examples of the coupling agent include γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-mercaptopropyltrimethoxy. Silane, γ-aminopropyltriethoxysilane, γ-aminopropyltriethoxyaluminum and the like can be mentioned, and one or more can be used.
The processing amount of the coupling agent is preferably 0.1 to 20 parts by mass and more preferably 1 to 10 parts by mass with respect to 100 parts by mass of the inorganic oxide particles and / or organic particles.

The hard coat layer may contain a flexible component. When the flexible component is contained, generation of cracks when the conductive laminate is punched can be further prevented.
Here, the flexible component is a (meth) acrylate having a polymerizable unsaturated group having one or more polymerizable unsaturated groups in the molecule. Examples of the (meth) acrylates include tricyclodecanemethylol di (meth) acrylate, ethylene oxide modified di (meth) acrylate of bisphenol F, ethylene oxide modified di (meth) acrylate of bisphenol A, ethylene oxide of isocyanuric acid Modified di (meth) acrylate, polypropylene glycol di (meth) acrylate, bifunctional (meth) acrylate such as polyethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylpropane propylene oxide modified tri (meth) Trifunctional (meth) acrylate such as acrylate, trimethylpropane ethylene oxide modified tri (meth) acrylate, urethane (meth) acrylate, polyester Meth) acrylate, polyether (meth) acrylate. In particular, it is more preferable to select trifunctional (meth) acrylate and urethane (meth) acrylate.
These (meth) acrylates can be used singly or in combination of two or more.

[Method for producing conductive sheet]
The conductive sheet 10 of FIG. 1 is obtained by forming the conductive layer 12 on one surface of the insulating layer 11 (conductive layer forming step). Here, if necessary, patterning of the conductive layer 12 and formation of the extraction electrode can be performed.
As described above, a known method such as a method of applying a coating liquid for forming a conductive layer or a method of printing ink for forming a conductive layer can be employed for forming the conductive layer 12.

Examples of the coating method include a method using a blade coater, an air knife coater, a roll coater, a bar coater, a gravure coater, a micro gravure coater, a rod blade coater, a lip coater, a die coater, a curtain coater, and the like. A microgravure coater is preferably used for forming the conductive layer 12 having a small target coating amount.
Examples of the printing method include screen printing, offset printing, flexographic printing, gravure offset printing, and ink jet printing.

  A known method such as coating or printing is employed for forming other layers such as an anchor layer provided on the insulating base material as necessary, for example, formation of an anchor layer or the like having a relatively small coating amount. It is preferable to use a micro gravure coater.

For example, a heated air dryer or a vacuum dryer is used for drying when forming the conductive layer 12 or these layers.
Further, when the resin component used for the conductive layer 12 is thermosetting, a heat treatment can be performed at the time of forming the conductive layer, using a heating furnace, an infrared lamp, or the like, at the time of drying the coating film or using a muro. When the resin component is active energy ray curable, the active energy ray is irradiated. Examples of the active energy rays include ultraviolet rays and electron beams. Among them, ultraviolet rays are preferable from the viewpoint of versatility.

As the ultraviolet light source, for example, a high pressure mercury lamp, a low pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, a carbon arc, a xenon arc, an electrodeless ultraviolet lamp, or the like can be used. As the electron beam, for example, an electron beam emitted from various electron beam accelerators such as a cockloftwald type, a bandecraft type, a resonant transformation type, an insulating core transformer type, a linear type, a dynamitron type, and a high frequency type can be used.
Curing by irradiation with active energy rays is preferably performed in the presence of an inert gas such as nitrogen in order to avoid curing inhibition by oxygen in the atmosphere, and nitrogen gas can be suitably used from the viewpoint of cost. In addition, the active energy ray irradiation process may be performed in two stages, a preliminary curing process and a main curing process.

In addition, the coating liquid and ink for forming other layers for forming the conductive layer or the anchor layer contain a solvent for dilution in addition to the active ingredient for the purpose of improving coating suitability and printability. May be. Examples of the solvent include water, alcohol (methanol, ethanol, isopropanol, n-butyl alcohol, etc.), ketone (acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl butyl ketone, ethyl butyl ketone, cyclohexanone, etc.), ether (for example, , Diethyl ether, methyl cellosolve, ethyl cellosolve, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, etc.), toluene, n-hexane, ethyl acetate, butyl acetate, N-methyl-2-pyrrolidone, etc. 1 or more types can be used.
In order to reduce coating unevenness, it is preferable to use solvents having different evaporation rates. For example, it is preferable that a plurality of solvents are appropriately selected from methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, and propylene glycol monomethyl ether, and these are mixed and used.

  Moreover, it is preferable to adjust pH of the coating liquid and ink for conductive layer formation to 1-6. If the pH is high, the coating solution or ink may gel due to the nitrogen-containing silane coupling agent contained in the coating solution or ink. When the pH is high, an acidic solution such as sulfuric acid or hydrochloric acid may be added to the coating liquid and ink.

In addition, when the patterning of the conductive layer 12 is necessary, the conductive layer 12 may be formed only at a necessary portion by, for example, a gravure coater or various printing methods, or after forming a uniform conductive layer in advance, a known wet process is performed. Alternatively, unnecessary portions may be removed by a dry etching method (such as ablation by laser light).
When wet etching is performed, an etching process may be performed after masking a part of the conductive layer by a photolithography method or a screen printing method using various active energy rays. For this process, Japanese Patent Application Laid-Open No. 2008-091487 may be used. Etching solutions for organic conductive polymers described in JP-A-2008-115310 and the like can be suitably used. Alternatively, the etching process may be carried out without masking by directly printing an etching paste such as an ishipe Higper Etch product manufactured by Merck Ltd. on the removed portion of the conductive layer.

<Conductive laminate with conductive sheet>
By using the above-described conductive sheet, conductive laminates having various configurations can be manufactured.
Hereinafter, the conductive laminate will be described with reference to first to third embodiments.

(1) First Embodiment Example The conductive laminate 1 in FIG. 2 includes an insulating layer 11, a conductive layer 12 formed on one side of the insulating layer 11, an adhesive layer 21 formed on the conductive layer 12, It has the peeling 1st base material 22 which coat | covers the surface on the opposite side to the conductive layer 12 in the adhesion layer 21. FIG. The conductive laminate 1 includes a pair of conductive layers 12 and an adhesive layer 21 that are in direct contact with each other, and has a configuration in which the conductive layer 12 is in contact with one surface of the insulating layer 11.

In addition, the sectional views shown below mainly show the layer structure, and there are places where dimensions and thickness are emphasized as appropriate, and are not shown accurately.
In the example of FIG. 2, the conductive layer 12 and the adhesive layer 21 are in contact with each other, but there is a form in which the conductive layer and the adhesive layer are in contact with each other.

When manufacturing the conductive laminate 1 of FIG. 2, first, as shown in FIG. 3, the adhesive layer 21 is formed on one surface of the first substrate for peeling (base material for peeling) 22. The coating liquid is applied and dried to form the pressure-sensitive adhesive layer 21, and the second substrate 23 for peeling is bonded thereon to obtain the pressure-sensitive adhesive sheet 20 (pressure-sensitive adhesive layer forming step).
Note that it is preferable that the peeling force of the peeling first base material 22 and the peeling force of the peeling second base material 23 be different because only one of the peeling bases is easily peeled first.

Next, the second substrate 23 for peeling is peeled off from the pressure-sensitive adhesive sheet 20 in FIG. 3 to expose the pressure-sensitive adhesive layer 21, and the pressure-sensitive adhesive layer 21 and the conductive layer 12 of the conductive sheet 10 in FIG. 2 conductive laminate 1 is obtained (sticking step).
Then, the conductive laminate 1 is cut or punched as necessary, and processed into a desired form (cutting or punching step).
Note that the cutting or punching process is not limited to the form performed after the sticking process, and may be performed before the sticking process.

  As an adhesive for forming the adhesive layer 21, for example, a natural rubber adhesive, a synthetic rubber adhesive, an acrylic adhesive, a urethane adhesive, a silicone adhesive, and the like can be used. Moreover, any of solvent system, emulsion system, and water system may be sufficient. In particular, when used for optical applications, a solvent-based acrylic pressure-sensitive adhesive can be particularly preferably used from the viewpoint of transparency, weather resistance, durability, cost, and the like. Furthermore, from the viewpoint of adhesive quality, a polymer containing ethylhexyl acrylate or butyl acrylate as a monomer unit is particularly preferable. Moreover, an auxiliary agent may be added to the pressure-sensitive adhesive as necessary. Examples of auxiliary agents include ultraviolet absorbers, thickeners, pH adjusters, tackifiers, binder components, crosslinking agents, adhesive fine particles, antifoaming agents, antiseptic / antifungal agents, and the like.

For the formation of the pressure-sensitive adhesive layer 21, a method of applying the coating liquid for forming the pressure-sensitive adhesive layer with the above-mentioned various coaters is suitable, and among them, it is preferable to use a lip coater or a die coater.
The optimum thickness of the pressure-sensitive adhesive layer varies depending on the use environment and composition and cannot be defined unconditionally, but is preferably 5 to 500 μm, more preferably 10 to 300 μm. If it is 5 μm or more, sufficient adhesiveness is easily obtained, while if it is 500 μm or less, the conductive laminate 1 is not easily deformed excessively, and the position detection ability is hindered when it is used as a touch panel. It will never be.
In addition, as the pressure-sensitive adhesive, those in which an acidic group such as a carboxyl group, a phosphoric acid group, or a sulfonic acid group is bonded to a part of the polymer that is the main component of the pressure-sensitive adhesive can be used.

  The coating solution for forming the adhesive layer may also contain a diluting solvent for the purpose of improving the coating suitability. As such a solvent, the solvent illustrated previously as the solvent for dilution used for the coating liquid and ink for conductive layer formation can be used similarly.

As the 1st base material 22 for peeling, and the 2nd base material 23 for peeling, what carried out mold release processing of sheet surfaces, such as various sheets previously illustrated as an insulating base material, and paper, is used suitably. For the release treatment, a condensation-type or addition-type silicone release agent, a non-silicone release agent such as an olefin, a long-chain alkyl group-containing polymer, or a fluorine is used. The sheet is preferably a resin film such as polyester or polypropylene or paper from the viewpoint of physical properties and cost.
The first substrate for peeling 22 is peeled from the conductive laminate 1. Then, for example, a cover glass (transparent sheet) or a polarizing plate surface of the liquid crystal module is bonded to the adhesive layer 21 exposed thereby.

The conductive laminate 1 in FIG. 2 can be produced, for example, by the following method (a) or method (b), and there is no particular limitation.
(A) On the surface of the conductive layer 12 in the conductive sheet 10, a coating solution for forming the adhesive layer 21 is directly applied and dried to form the adhesive layer 21, and the first substrate 22 for peeling is pasted thereon. To wear.
(B) A coating solution for forming the adhesive layer 21 is applied and dried on one surface of the first substrate 22 for peeling to form the adhesive layer 21, and the conductive layer 12 side of the conductive sheet 10 is formed thereon. Adhere.

(2) Second Embodiment The conductive laminate 1 of the first embodiment includes a pair of conductive layers 12 and an adhesive layer 21 and has an insulating layer 11 made of an insulating substrate. Is located in contact with the insulating layer 11. On the other hand, the conductive laminate of the second embodiment differs from the first embodiment in that it includes a peelable substrate instead of the insulating substrate 11.
Such a conductive laminate can be used in combination with another member on the conductive layer side after peeling of the peelable substrate. As the peelable substrate, those exemplified above as the first substrate for peeling can be suitably used.

(3) Third Embodiment FIG. 4 is a cross-sectional view showing a conductive laminate 1 ′ of a third embodiment. The conductive laminate 1 ′ in this example has a conductive layer 12, an adhesive layer 21, and a first substrate for peeling on the surface opposite to the conductive layer 12 in the insulating layer 11 of the conductive laminate 1 shown in FIG. 2. 22 is sequentially laminated. In this embodiment, the conductive layer 12, the adhesive layer 21, and the first substrate for peeling 22 formed on both sides of the insulating layer 11 are layers having different compositions even if they are layers having the same composition on both sides. There may be.
When each conductive layer 12 is patterned in the conductive laminate 1 ′ having such a configuration, specifically, each conductive layer 12 is formed in a pattern having regularity in a uniaxial direction, and each conductive layer When the twelve patterns are in a positional relationship orthogonal to each other, the conductive laminate 1 ′ is preferably used as a main member of a projected capacitive touch panel as described below.

<Touch panel>
FIG. 5 is a cross-sectional view illustrating an example of a liquid crystal module including the touch panel 100 of the present invention that is a projected capacitive type. The touch panel 100 includes two sheets from the conductive laminate 1 ′ of FIG. The electroconductive sheet which peeled the 1st base material 22 for peeling is comprised. Each of the conductive layers 12 (U) and 12 (L) acting as the upper electrode and the lower electrode on both surfaces of the insulating layer 11 is processed into a pattern having regularity in the uniaxial direction, and 12 of each conductive layer. The patterns (U) and 12 (L) are arranged so as to be orthogonal to each other for position detection.

The conductive layer 12 (U) on the upper electrode side is bonded to a cover member (transparent sheet) 101 made of a transparent material such as glass or film via an adhesive layer 21 (U). The adhesive layer 21 (L) is laminated on the conductive layer 12 (L) on the lower electrode side, and is bonded to, for example, the polarizing plate surface of the liquid crystal module 102 via this.
The conductive layers 12 (U) and 12 (L) include a lead electrode layer (not shown), and the lead electrode layer and the FPC (flexible wiring board) connector 104 are connected. Further, the FPC connector 104 is an FPC or the like. Is connected to the capacitance detection circuit 105 to constitute the touch panel 100.
In addition, since the structure of a touch panel is various for every manufacturer or model, it is not limited to this.

  Thus, for example, by using the conductive laminate 1 ′ in the example of FIG. 4, the projected capacitive touch panel 100 as used in the liquid crystal module of FIG. 5 can be easily manufactured. Since the conductive layers 12 (U) and 12 (L) of the touch panel 100 include at least one kind of the nitrogen-containing silane coupling agent and its reaction product, it has excellent durability under high temperature and low humidity conditions. , The decrease in conductivity is suppressed.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples. In the examples, “%” indicates mass% unless otherwise specified.

[Example 1]
(Preparation of conductive sheet)
An aqueous dispersion containing a conductive material (PEDOT-PSS) obtained by polymerizing (3,4-ethylenedioxythiophene) in the presence of polystyrene sulfonic acid, and a polyester resin (Toyobo Co., Ltd.) as a resin component of the binder component Manufactured by Vylonal MD1200) and surfactant (manufactured by Shin-Etsu Chemical Co., Ltd., leveling agent KP-110) are mixed at a mass ratio of 1: 1: 1 as a solid content, diluted with methanol, and a solid content concentration of 1 % Mixture A.
This mixture A and a nitrogen-containing silane coupling agent, an isocyanurate-based silane coupling agent (X-12-965, manufactured by Shin-Etsu Chemical Co., Ltd.) diluted with methanol to give a 1% solution, The mixture was mixed at a mass ratio of 100: 30 to prepare a coating solution for forming a conductive layer.
This coating solution was applied to the first base material constituting the insulating layer 11 (“biaxially stretched polyethylene terephthalate film provided with an easy adhesion treatment layer on both sides” (trade name “Cosmo Shine A4300”, manufactured by Toyobo Co., Ltd., thickness 100 μm)) on one side, coated with a bar coater to a dry thickness of about 0.2 μm, and then dried to form a conductive layer 12, surface resistance of 273 Ω / sq (JIS-K7194 compliant), total light transmission A transparent conductive sheet 10 having a configuration shown in FIG. 1 having a rate (based on JIS-K7105) of 89.9% was obtained.
Furthermore, a double-sided conductive sheet having a conductive layer formed on the other side of the insulating layer was also obtained for the touch panel.

(Preparation of adhesive sheet)
<Preparation of coating solution for forming an adhesive layer>
Nitrogen gas was sealed in a reactor equipped with a stirrer, a thermometer, a reflux condenser, a dropping device, and a nitrogen introduction tube, and then ethyl acetate as a solvent was added. Next, in the reactor, 65 parts by mass of butyl acrylate as an acrylic monomer, 35 parts by mass of methyl acrylate, 2 parts of acrylic acid, and 0.1 mass of 2,2′-azoisobutyronitrile as a polymerization initiator. The polymer was polymerized for 8 hours at the reflux temperature of the solvent in a nitrogen gas stream while stirring. After completion of the reaction, toluene was added to obtain an acrylic polymer solution. To 100 parts by mass of this acrylic polymer solid content, 2.0 parts by mass of a hindered amine compound (product name: TINUVIN 144, manufactured by BASF) as a light stabilizer, and a hindered phenol compound (trade name: IRGANOX 1520L) as an antioxidant. 0.08 parts by mass) (manufactured by BASF) was added to obtain an adhesive main agent.
Next, with respect to 100 parts by mass of the pressure-sensitive adhesive main component, 1 part of tolylene diisocyanate (product name: Coronate L, manufactured by Nippon Polyurethane Co., Ltd.), a benzotriazole-based liquid ultraviolet absorption having a maximum absorption wavelength at a wavelength of 353 nm 4.0 parts by mass of an agent (product name: TINUVIN109, manufactured by BASF) was mixed to obtain a coating solution for forming an adhesive layer.

<Production of adhesive sheet>
Using the prepared coating liquid for forming an adhesive layer, an adhesive sheet 20 having the configuration shown in FIG. 3 was prepared as follows.
Using a bar coater, the adhesive layer-forming coating solution is dried on a 38 μm thick PET release film (product name: 38RL07 (5), manufactured by Oji Specialty Paper Co., Ltd.) as the first substrate 22 for release. The coating amount was 175 g / m ² and dried at 100 ° C. for 5 minutes to form an adhesive layer 21. Next, a 38 μm-thick PET release film (product name: 38RL07 (2), Oji Specialty Paper Co., Ltd.) that has been subjected to a release treatment on the surface of the pressure-sensitive adhesive layer 21 so that the release force is lighter than that of the first substrate 22 for release. (Made by company) as a second substrate 23 for peeling, and then left at room temperature for one week, and a pressure-sensitive adhesive sheet comprising a layer configuration of first substrate 22 for peeling / adhesive layer 21 / second substrate 23 for peeling 20 was produced.

(Production of touch panel)
A dry film for photoresist is laminated on the conductive layer of the above-described double-sided conductive sheet, a quartz mask is overlaid, and a metal halide lamp (multi-metal lamp for ultraviolet curing M03-L31, manufactured by Eye Graphics Co., Ltd.) A process of irradiating ultraviolet rays with an irradiation amount of 300 mJ / cm ² on each side was performed on both sides. The pattern of the quartz mask was a pattern shape in which the XY electrode patterns were arranged orthogonally on both surfaces of the insulating layer made of the first substrate so that the position could be detected as a touch panel sensor. In this case, the amount of ultraviolet rays that passed through the first base material and reached the opposite coated surface by the ultraviolet irradiation was very small, so that the patterning of the opposite surface was not reversed. Subsequently, a part of the conductive layer was removed together with the uncured resist using an organic polymer type conductive layer etching solution, and then the remaining resist film was peeled off to obtain a double-side patterned conductive film.

  A lead electrode wire was formed using a silver paste around the double-sided patterned conductive film and connected to the FPC connector. Subsequently, 1 mm-thick optical glass 101 was bonded to both surfaces of each patterned conductive layer using two adhesive sheets, and a touch panel module 100 ′ having a configuration shown in FIG. 6 was produced.

1) Durability Evaluation of Transparent Conductive Sheet A sample of a transparent conductive sheet was cut out to 5 cm × 10 cm, conditioned at room temperature and normal humidity (23 ° C., 50 RH%) for 24 hours, and then Loresta EP manufactured by Mitsubishi Chemical Analytech Co., Ltd. : Using MCP-T360, the surface resistance (before the durability test) was measured by a method based on JIS-K7194 (Rs ₀ ). This sample was transferred into a constant temperature chamber (80 ° C. Dry; non-humidified) of 80 ° C., which is a high temperature and low humidity environment, and left for 240 hours for a durability test. Thereafter, the sample was returned to a normal temperature and normal humidity environment, and after adjusting the humidity for 24 hours, the surface resistance (after the durability test) was measured by the same method (Rs). The evaluation results are shown in Table 1.
2) Evaluation as a touch panel The touch panel module 100 ′ produced in Example 1 is also transferred to a constant temperature chamber (80 ° C. Dry; non-humidified) of 80 ° C., which is a high temperature and low humidity environment, and 240 for durability test. After being allowed to stand for a period of time, operation was confirmed in a normal temperature and humidity environment, and evaluation was performed according to the following indices. The evaluation results are shown in Table 1.
(Criteria)
A: Good responsiveness was exhibited as before the test.
B: The detection sensitivity was slightly deteriorated.
C: Detection sensitivity deteriorated.

[Example 2]
In the same manner as in Example 1, except that a ureido silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., KBE-585) was used as the silane coupling agent used in the coating solution for forming the conductive layer, the surface A transparent conductive sheet 10 having a resistance of 274Ω / sq and a total light transmittance of 90.0% and a touch panel module 100 ′ were obtained. And it evaluated similarly to Example 1. FIG. The results are shown in Table 1.

[Example 3]
As the silane coupling agent used in the coating solution for forming the conductive layer, a ureido-based silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., KBE-585) and an epoxy-based silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., KBE) -403) The transparent conductive sheet 10 having a surface resistance of 271 Ω / sq and a total light transmittance of 89.9% was used in the same manner as in Example 1 except that the same amount mixture (calculated by the solid content ratio) was used. The touch panel module 100 ′ was obtained.
The total amount of the ureido silane coupling agent and the epoxy silane coupling agent is the same as the amount of the isocyanurate coupling agent of Example 1. And it evaluated similarly to Example 1. FIG. The results are shown in Table 1.

[Comparative Example 1]
As in Example 1, except that an epoxy silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., KBE-403) was used alone as the silane coupling agent used in the coating liquid for forming the conductive layer. A transparent conductive sheet 10 having a surface resistance of 270 Ω / sq and a total light transmittance of 89.6% and a touch panel module 100 ′ were obtained. And it evaluated similarly to Example 1. FIG. The results are shown in Table 1.

  As shown in Table 1, in Examples 1 to 3 using a nitrogen-containing silane coupling agent, the change in the surface resistance value was small before and after the endurance test in a high-temperature and low-humidity environment as compared with Comparative Example 1, and over time. The decrease in conductivity was reduced.

10 conductive sheet 11 insulating layer 12 conductive layer

Claims (5)

Containing at least a polythiophene-based conductive agent and a coupling agent component,
The conductor is characterized in that the coupling agent component contains at least one of a nitrogen-containing silane coupling agent and a reaction product thereof.   The conductor according to claim 1, wherein the nitrogen-containing silane coupling agent has one or more of a ureido group, a ureylene group, and an isocyanurate group.   A conductive sheet comprising a conductive layer made of the conductor according to claim 1 on at least one surface of an insulating layer.   A touch panel comprising the conductive sheet according to claim 3.   The touch panel according to claim 4, wherein the conductive sheet has the patterned conductive layer on both surfaces of the insulating layer.

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