WO2013141275A1

WO2013141275A1 - Transparent conductive laminate and touch panel

Info

Publication number: WO2013141275A1
Application number: PCT/JP2013/057990
Authority: WO
Inventors: 昌哉中山
Original assignee: 富士フイルム株式会社
Priority date: 2012-03-23
Filing date: 2013-03-21
Publication date: 2013-09-26
Also published as: JP5749207B2; JP2013198990A

Abstract

This transparent conductive laminate comprises: a first barrier film (1); a patterned transparent conductive film (2) which contains metal nanowires having an average minor axis length of 5-50 nm and is formed on the surface of the first barrier film (1) directly or with another layer being interposed therebetween; an adhesive layer (3) that covers the patterned transparent conductive film (2); and a second barrier film (4) that is arranged adjacent to the adhesive layer (3). The water vapor transmission rates of the first and second barrier films (1, 4) are 0.1 g/(m²·day) or less.

Description

Transparent conductive laminate and touch panel

The present invention relates to a transparent conductive laminate and a touch panel.

In recent years, mobile devices equipped with touch panels are increasing. In particular, capacitive touch panels have become mainstream because two or more simultaneous detections are possible and various input methods are possible. ITO glass and ITO film are widely used as transparent conductive materials for touch panels, but indium metal is a rare metal and has low color transmittance and low resistance due to low light transmittance in the long wavelength region. Since there are problems such as the necessity of high-temperature heat treatment and low bending resistance, various alternative materials for ITO glass and ITO film have been studied.

As one of alternative materials, conductive materials using conductive metal nanowires are known. Metal nanowires are excellent in terms of transparency, low resistance, and reduction in the amount of metal used, so ITO glass and Expectation as an alternative material for ITO film is increasing. In particular, it is known that by using a metal nanowire having an average minor axis length of 50 nm or less, a transparent conductive film with low light scattering and excellent visibility can be provided (for example, a patent) Reference 1).

Capacitive touch panels are required to be thinner, lighter, and less expensive. The substrate of the transparent substrate is changed to a film, and the cover lens (transparent protective substrate) of the touch panel is changed from a conventional glass to a film. It has been proposed to reduce the thickness, weight, and cost (for example, Patent Document 2).

JP 2012-3900 A JP 2011-59834 A

As a result of the inventor's examination of the above prior art, in the capacitive touch panel, the transparent substrate and the cover lens (transparent protective substrate) are changed from glass to a polymer film, and the transparent conductive film having metal nanowires ( In the following, when using simply “conductive film”), it has been found that the touch panel becomes inoperable or malfunctions when driven under high temperature and high humidity. Moreover, this problem discovered that the resistance value of the transparent conductive film which has metal nanowire rose while driving under high temperature, high humidity. And this resistance increase is found to be a phenomenon that occurs when a voltage is applied between line electrodes patterned in a line shape under high temperature and high humidity. Further, this resistance increase is caused by low haze, high transmittance, It has been found that this phenomenon appears prominently in a transparent conductive film using metal nanowires having an average minor axis length of 50 nm or less enabling low resistance.

An object of the present invention is to solve the above-described problems, and specifically, a thin and light transparent conductive laminate having low resistance and no haze even when a voltage is applied under high temperature and high humidity, and its transparent conductive It is an object of the present invention to provide a touch panel that is thin, lightweight, and has excellent visibility, which does not cause malfunction even when driven under high temperature and high humidity, by using lamination.

As a result of various studies conducted by the present inventors in order to solve the above problems, the inventors have obtained knowledge that the above problems can be solved by providing a barrier film having a predetermined water vapor transmission rate, thereby completing the present invention. It was.

Means for solving the above-mentioned problems are the transparent conductive laminates and touch panels [1] and [9] below, and preferably the transparent conductive laminates and touch panels [2] to [10] below.
[1] A first barrier film, a patterned transparent conductive film containing metal nanowires having an average minor axis length of 5 to 50 nm, formed directly on the surface of the first barrier film or via another layer, and a pattern It has an adhesive layer covering the transparent conductive film and a second barrier film adjacent to the adhesive layer, and the water vapor permeability of the first and second barrier films is 0.1 g / (m ² · day), respectively. A transparent conductive laminate characterized by the following.
[2] The pattern of the first barrier film has a transparent film made of resin on the surface opposite to the surface on which the transparent conductive film is formed, and on the side opposite to the surface adjacent to the adhesive layer of the second barrier film The transparent conductive laminate according to [1], having a transparent protective film made of resin on the surface.
[3] The transparent conductive laminate according to [1] or [2], wherein the metal nanowire has an average minor axis length of 5 to 25 nm.
[4] The transparent conductive laminate according to any one of [1] to [3], wherein the adhesive strength of the adhesive layer is 15 N / 25 mm or more.
[5] The transparent conductive laminate according to any one of [1] to [4], wherein the adhesive strength of the adhesive layer is 30 to 50 N / 25 mm.
[6] The transparent conductive laminate according to any one of [1] to [5], wherein the water absorption of the adhesive layer is 1.0% or less.
[7] The transparent conductive laminate according to any one of [1] to [6], wherein the metal nanowire contains silver.
[8] The transparent conductive laminate according to any one of [1] to [7], wherein the first and second barrier films are SiON, and the film thicknesses of the first and second barrier films are 300 nm or less, respectively. body.
[9] A touch panel using the transparent conductive laminate according to any one of [1] to [8].
[10] The touch panel according to [9], wherein the drive voltage is 1 V or more.

According to the present invention, a thin and lightweight transparent conductive laminate that does not increase resistance even when a voltage is applied under high temperature and high humidity, and has a low haze, and the transparent conductive laminate is used to drive under high temperature and high humidity. However, it is possible to provide a touch panel that is thin, lightweight, and has excellent visibility without causing malfunction.

It is a cross-sectional schematic diagram of an example of the transparent conductive laminated body of this invention. It is a cross-sectional schematic diagram of an example of the touch panel of this invention. It is a cross-sectional schematic diagram of the other example of the touchscreen of this invention. It is a top view of the element produced in the Example. FIG. 5 is a cross-sectional view taken along line X-X ′ in FIG. 4. It is a cross-sectional schematic diagram of the touch panel of a comparative example.

Hereinafter, the present invention will be described in detail. In the present specification, a numerical range represented by using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

FIG. 1 shows a schematic diagram of an example of the transparent conductive laminate of the present invention. The transparent conductive laminate of the present invention includes a first barrier film, a patterned transparent conductive film containing metal nanowires having an average minor axis length of 5 to 50 nm formed directly on the surface of the first barrier film, An adhesive layer covering the transparent conductive film; and a second barrier film adjacent to the adhesive layer. In FIG. 1, the transparent conductive film is provided on the surface of the first barrier film, but the transparent conductive film may be provided via another layer. The other layer includes an embodiment in which one or more layers or films are provided on the surface of the first barrier film and a transparent conductive film is provided on the surface. In the present invention, it is preferable to provide a transparent conductive film on the surface of the first barrier film. The patterned transparent conductive film is patterned in a line shape in a conductive area and a non-conductive area, and metal nanowires having an average minor axis length of 5 to 50 nm are contained in the conductive area. The water vapor transmission rates of the first and second barrier films are each 0.1 g / (m ² · day) or less.

The first barrier film is formed directly (adjacent) to the pattern transparent conductive film, and the second barrier film is adjacent to the adhesive layer by adhering to the adhesive layer.
The first and second barrier films have a function of preventing moisture entering from the outside from entering the pattern transparent conductive film, and the water vapor permeability of the first and second barrier films is 0.1 g. / (m ² · day) or less, is preferably 0.05 g / (m ² · day) or less. Although there is no specific lower limit of the water vapor transmission rate, it is generally 0.000001 g / (m ² · day) or more.

The first barrier film may have a transparent film made of a resin that supports the first barrier film on the surface opposite to the surface on which the patterned transparent conductive film is formed. The whole including the barrier film is defined as a substrate. As a board | substrate, a thing with a high light transmittance is good, 70% or more is preferable and 80% or more is more preferable. Other functional layers such as an undercoat layer may be provided between the transparent film and the first barrier film. Other functional layers include, for example, matting agent layers, protective layers, solvent resistant layers, antistatic layers, smoothing layers, adhesion improving layers, light shielding layers, antireflection layers, hard coat layers, stress relaxation layers, antifogging layers. , Antifouling layer, printed layer, easy adhesion layer and the like. These may be a single layer or a plurality of layers.
Further, the patterned transparent conductive film is formed directly on the surface of the first barrier film or via another layer, that is, the patterned transparent conductive film is formed on the transparent film or functional layer that supports the first barrier film. Also good.

The second barrier film has a transparent protective film made of a resin supporting the second barrier film on the surface opposite to the surface adjacent to the adhesive layer, and includes the second barrier film and the transparent protective film. Is defined as a cover film. As a cover film, a thing with a high light transmittance is good, 70% or more is preferable and 80% or more is more preferable. Furthermore, it is preferable that the surface of the transparent protective film opposite to the side on which the second barrier film is formed has a hard coat layer. A hard coat layer having a hardness of 3H or more is preferable. Other functional layers such as an undercoat layer may be provided between the transparent protective film and the second barrier film and between the transparent protective film and the hard coat layer. Other functional layers include, for example, matting agent layers, protective layers, solvent resistant layers, antistatic layers, smoothing layers, adhesion improving layers, light shielding layers, antireflection layers, stress relaxation layers, antifogging layers, and antifouling layers. , Printing layer, easy adhesion layer and the like. These may be a single layer or a plurality of layers. These may be a single layer or a plurality of layers.
Details of the first and second barrier films will be described later.

The adhesive layer is composed of an adhesive. As a result of the inventor's earnest research, the present inventor found that moisture in the outside air also entered from the adhesive layer, and found that this had an effect on the increase in resistance of the patterned transparent conductive film. For this reason, it is preferable that the water absorption rate of an adhesion layer is 2.0% or less, It is more preferable that it is 1.0% or less, It is especially preferable that it is 0.9% or less.

The adhesive strength of the adhesive layer (here, the adhesive strength with the second barrier film) is preferably 15 N / 25 mm or more, more preferably 30 to 50 N / 25 mm, and more preferably 30 to 42 N / 25 mm. It is particularly preferred. By setting the adhesive strength to 15 N / 25 mm or more, peeling between the second barrier film and the adhesive layer does not occur, and an effect of preventing moisture from entering from the interface between the second barrier film and the adhesive layer is obtained. Further, when the thickness is 30 N / 25 mm or more, a strong effect can be obtained in preventing moisture from entering from the interface between the second barrier film and the adhesive layer, and an increase in resistance of the patterned transparent conductive film can be prevented. However, when it exceeds 50 N / 25 mm, the flexibility of the transparent conductive laminate may be inferior.

Hereinafter, various members used in the present invention will be described in detail.

First and second barrier films:
In this invention, it has the 1st barrier film adjacent to a pattern transparent conductive film, and the 2nd barrier film adjacent to an adhesion layer. Hereinafter, the first and second barrier films are also referred to as “barrier films”.

The barrier film preferably has an inorganic barrier layer from the viewpoint of water vapor barrier performance. However, an inorganic barrier layer is not necessarily required as long as the water vapor permeability of the barrier film satisfies 0.1 g / (m ² · day) or less. Further, the barrier film may have a structure in which at least one inorganic barrier layer or an organic layer described later is laminated. The inorganic barrier layer and the organic layer may be stacked in this order, or the organic layer and the inorganic barrier layer may be stacked in this order. The uppermost layer may be an inorganic barrier layer or an organic layer.

Barrier film, water vapor transmission ^{rate, 0.1g / (m 2 · day} ) or less ^{(preferably, 0.05g / (m 2 · day} ) or less) if the material etc. are not particularly limited. Further, the first and second barrier films may be the same barrier film or different barrier films.

(Inorganic barrier layer)
The inorganic barrier layer is usually a thin film layer made of a metal compound. As a method for forming the inorganic barrier layer, any method can be used as long as it can form a target thin film (layer). For example, there are a physical vapor deposition method (PVD) such as a vapor deposition method, a sputtering method, and an ion plating method, various chemical vapor deposition methods (CVD), and a liquid phase growth method such as plating and a sol-gel method. The component contained in the inorganic barrier layer is not particularly limited as long as it satisfies the above performance, but for example, a metal oxide, a metal nitride, a metal carbide, a metal oxynitride, or a metal oxycarbide, Si, Al, An oxide, nitride, carbide, oxynitride, oxycarbide, or the like containing one or more metals selected from In, Sn, Zn, Ti, Cu, Ce, and Ta can be preferably used. Among these, a metal oxide, nitride or oxynitride selected from Si, Al, In, Sn, Zn and Ti is preferable, and a metal oxide, nitride or oxynitride of Si or Al is particularly preferable, Specifically, SiON (silicon nitride oxide) is preferable. These may contain other elements as secondary components.
The smoothness of the inorganic barrier layer formed according to the present invention is preferably less than 20 nm, more preferably 1 nm or less, as an average roughness (Ra value) of 1 μm square. The inorganic barrier layer is preferably formed in a clean room. The degree of cleanness is preferably class 10000 or less, more preferably class 1000 or less.

Although the thickness of the inorganic barrier layer is not particularly limited, it is usually in the range of 5 to 500 nm, preferably 10 to 300 nm per layer. The inorganic barrier layer may have a laminated structure including a plurality of sublayers. In this case, each sublayer may have the same composition or a different composition. Even in the case of a laminated structure composed of a plurality of sublayers, the preferable thickness as the total thickness of the inorganic barrier film is usually 10 to 2000 nm, more preferably 20 to 300 nm. If the total thickness of the inorganic barrier layer exceeds 300 nm, the flexibility such as the cracking of the inorganic barrier layer is likely to occur when it is bent. As disclosed in US Patent Publication No. 2004-46497, a layer in which the interface between the inorganic barrier layer and the organic layer is not clear and the composition continuously changes in the layer thickness direction may be used.

(Organic layer)
The organic layer in the present invention is preferably an organic layer containing an organic polymer as a main component. Here, the main component means that the first component of the component constituting the organic layer is an organic polymer, and usually 80% by mass or more of the component constituting the organic layer is an organic polymer.
Examples of the organic polymer include polyester, acrylic resin, methacrylic resin, methacrylic acid-maleic acid copolymer, polystyrene, transparent fluororesin, polyimide, fluorinated polyimide, polyamide, polyamideimide, polyetherimide, cellulose acylate, and polyurethane. , Polyether ether ketone, polycarbonate, alicyclic polyolefin, polyarylate, polyether sulfone, polysulfone, fluorene ring modified polycarbonate, alicyclic modified polycarbonate, fluorene ring modified polyester, acryloyl compound and other thermoplastic resins, or polysiloxane, etc. Examples thereof include organosilicon polymers. The organic layer may be composed of a single material or a mixture, or may be a laminated structure composed of a plurality of sublayers. In this case, each sublayer may have the same composition or different compositions. Further, as disclosed in US Patent Publication No. 2004-46497, a layer in which the interface between the inorganic barrier layer and the organic layer is not clear and the composition changes continuously in the film thickness direction may be used.

The organic layer in the present invention is preferably formed by curing a polymerizable composition containing a polymerizable compound.

(Polymerizable compound)
The polymerizable compound is preferably a radical polymerizable compound and / or a cationic polymerizable compound having an ether group as a functional group, more preferably a compound having an ethylenically unsaturated bond at the terminal or side chain, and / or A compound having an epoxy or oxetane at the terminal or side chain. Of these, compounds having an ethylenically unsaturated bond at the terminal or side chain are preferred. Examples of compounds having an ethylenically unsaturated bond at the terminal or side chain include (meth) acrylate compounds, acrylamide compounds, styrene compounds, maleic anhydride, etc., (meth) acrylate compounds and / or Styrenic compounds are preferred, and (meth) acrylate compounds are more preferred.

As the (meth) acrylate compound, (meth) acrylate, urethane (meth) acrylate, polyester (meth) acrylate, epoxy (meth) acrylate and the like are preferable.
As the styrene compound, styrene, α-methylstyrene, 4-methylstyrene, divinylbenzene, 4-hydroxystyrene, 4-carboxystyrene and the like are preferable.

(Polymerization initiator)
In the transparent conductive laminate of the present invention, when a polymerizable composition containing a polymerizable compound is applied and cured to form an organic layer, the polymerizable composition may contain a polymerization initiator. As the polymerization initiator, for example, a polymerizable initiator described in JP 2012-025099 A can be used.

(Formation method of organic layer)
A method for forming the organic layer is not particularly defined, but can be formed by, for example, a solution coating method or a vacuum film forming method. Specifically, the organic layer is formed by a method described in JP2012-025099A. can do. Examples of the solution coating method include a dip coating method, an air knife coating method, a curtain coating method, a roller coating method, a wire bar coating method, a gravure coating method, a slide coating method, or a method described in US Pat. No. 2,681,294. It can be applied by an extrusion coating method using a hopper. Although there is no restriction | limiting in particular as a vacuum film-forming method, Film-forming methods, such as vapor deposition and plasma CVD, are preferable. In the present invention, a polymer may be applied by solution, or a hybrid coating method containing an inorganic substance as disclosed in Japanese Patent Application Laid-Open Nos. 2000-323273 and 2004-25732 may be used.

The thickness of the organic layer is not particularly limited, but is usually in the range of 10 to 3000 nm, preferably 100 to 2000 nm per layer.

(Lamination of organic layer and inorganic barrier layer)
The organic layer and the inorganic barrier layer can be laminated by repeatedly laminating the organic layer and the inorganic barrier layer sequentially in accordance with a desired layer configuration. When the inorganic barrier layer is formed by a vacuum film formation method such as a sputtering method, a vacuum vapor deposition method, an ion plating method, or a plasma CVD method, the organic layer can also be formed by a vacuum film formation method such as the flash vapor deposition method. preferable. During the production of the transparent conductive laminate, it is particularly preferable to always laminate the organic layer and the inorganic barrier layer in a vacuum of 1000 Pa or less without returning to atmospheric pressure in the middle. The pressure is more preferably 100 Pa or less, more preferably 50 Pa or less, and further preferably 20 Pa or less.
In particular, the present invention can exhibit high barrier properties when at least two organic layers and at least two inorganic barrier layers are alternately laminated. The mode of alternately laminating is that the first barrier film is laminated in the order of the organic layer / inorganic barrier layer / organic layer / inorganic barrier layer from the transparent film side supporting the first barrier film, but the inorganic barrier layer / organic layer The layers may be laminated in the order of / inorganic barrier layer / organic layer. Similarly, in the second barrier film, even if the organic layer / inorganic barrier layer / organic layer / inorganic barrier layer are laminated in this order from the adhesive layer side, the inorganic barrier layer / organic layer / inorganic barrier layer / organic layer You may laminate | stack in order.

(Functional layer)
The barrier film may have a functional layer. The functional layer is described in detail in paragraph numbers 0036 to 0038 of JP-A-2006-289627. Examples of functional layers other than these include matting agent layers, protective layers, solvent resistant layers, antistatic layers, smoothing layers, adhesion improving layers, light shielding layers, antireflection layers, hard coat layers, stress relaxation layers, antifogging layers. , Antifouling layer, printed layer, easy adhesion layer and the like.

The thickness of each of the entire first barrier film and the entire second barrier film is not particularly limited and can be appropriately selected depending on the purpose. For example, the barrier layer is an organic layer or a laminate of an organic layer and an inorganic barrier layer. In this case, the thickness is preferably 50 to 10,000 nm, more preferably 100 to 5000 nm. In the case of stacking an organic layer and an inorganic barrier layer, a preferable range of the total thickness of the inorganic barrier layer is 10 to 2000 nm, and more preferably 20 to 300 nm. When the total thickness of the inorganic barrier layer exceeds 300 nm, as described above, the flexibility such that cracks are likely to occur in the inorganic barrier film when bent is deteriorated. When the barrier film is only an inorganic barrier layer, the preferred thickness of the barrier layer is in the range of 10 to 2000 nm, more preferably 20 to 300 nm. If the thickness exceeds 300 nm, as described above, the flexibility such as cracking of the inorganic barrier layer when bent is deteriorated.

Transparent film (support):
The transparent film supports the first barrier film. The light transmittance of the transparent film is preferably 65% or more, and more preferably 70% or more.

The material for the transparent film is not particularly limited as long as it is a flexible polymer (resin). For example, it can be selected from a polymer film (used to include both a resin and a polymer), a polymer sheet, and a polymer molded body.
Examples of usable polymer films include polyethylene terephthalate (PET), polycarbonate, polyethersulfone, polyester, acrylic resin, vinyl chloride resin, aromatic polyamide resin, polyamideimide, polyimide, FRP (fiber reinforced plastic), A film containing polymethyl methacrylate resin (PMMA) or the like as a main component is included.

The surface of the transparent film may be subjected to a surface treatment for improving adhesion with the first barrier film. The surface treatment is performed by a physical or chemical method. Examples of the physical method include a method of imparting an anchor effect by roughening the surface of the support by a sandblast method or the like. Examples of the chemical method include a method of activating the support surface by plasma treatment or corona treatment, a method of chemically increasing adhesion to the conductive film by silane coupling agent treatment, and a method of providing an undercoat layer such as a primer layer. Etc. The undercoat layer is not particularly limited and may be appropriately selected depending on the intended purpose. However, the undercoat layer may be provided with ultraviolet absorbing ability, antioxidant ability, and the like. Among these, plasma processing is particularly preferable in terms of simplicity and processing uniformity.

The thickness of the transparent film is not particularly limited. The average thickness is preferably 0.01 mm to 10 mm, and more preferably 0.02 mm to 1 mm. However, it is not limited to this range.

Transparent protective film:
The transparent protective film supports the second barrier film. The light transmittance of the transparent protective film is preferably 65% or more, and more preferably 70% or more.

The material for the transparent protective film is not particularly limited as long as it is a polymer. A flexible polymer may be used. For example, it can be selected from a polymer film (used to include both a resin and a polymer), a polymer sheet, and a polymer molded body.
Examples of usable polymer films include polyethylene terephthalate (PET), polycarbonate, polyethersulfone, polyester, acrylic resin, vinyl chloride resin, aromatic polyamide resin, polyamideimide, polyimide, FRP (fiber reinforced plastic), A film containing polymethyl methacrylate resin (PMMA) or the like as a main component is included.
The transparent protective film is preferably provided with a hard coat layer for preventing scratches on the surface in view of its function. The material of the hard coat layer is not limited, but a material having a pencil hardness of 3H or higher and a light transmittance of 70% or higher is preferable.

The surface of the transparent protective film may be subjected to a surface treatment for improving adhesion with the second barrier film. The surface treatment is performed by a physical or chemical method. Examples of the physical method include a method of imparting an anchor effect by roughening the surface of the substrate by a sandblast method or the like. Examples of the chemical method include a method of activating the substrate surface by plasma treatment or corona treatment, a method of chemically increasing adhesion to the conductive film by silane coupling agent treatment, and a method of providing an undercoat layer such as a primer layer. Etc. The undercoat layer is not particularly limited and may be appropriately selected depending on the intended purpose. However, the undercoat layer may be provided with ultraviolet absorbing ability, antioxidant ability, and the like. Among these, plasma processing is particularly preferable in terms of simplicity and processing uniformity.

The thickness of the transparent protective film is not particularly limited. The average thickness is preferably 0.01 mm to 10 mm, and more preferably 0.1 mm to 3 mm. However, it is not limited to this range.

Pattern transparent conductive film:
The patterned transparent conductive film of the present invention refers to a transparent conductive film patterned in a conductive area and a non-conductive area. The conductive area and the non-conductive area may be patterned in a line shape or may not necessarily be patterned in a line shape.
The non-conductive area indicates an area having a sheet resistance of 10 ⁷ Ω / □ or more.
The patterned transparent conductive film used in the present invention is formed from a composition for forming a transparent conductive film containing metal nanowires.
In addition, although metal nanowire may not remain by etching etc. in the said nonelectroconductive area, it may remain.

Metal nanowire:
In this specification, the metal nanowire refers to a metal nanowire having conductivity and having a shape in which the length in the major axis direction is sufficiently longer than the diameter (length in the minor axis direction). It may be a solid fiber or a hollow fiber.

There is no restriction | limiting in particular as a material of the said metal nanowire, According to the objective, it can select suitably, For example, the group which consists of a 4th period of a long period table (IUPAC1991), a 5th period, and a 6th period At least one metal selected from the group consisting of at least one metal selected from the group consisting of the fourth period, the fifth period, and the sixth period, and at least one type selected from the group 2 to group 14 Metal is more preferred, at least one metal selected from the group consisting of the fourth period, the fifth period, and the sixth period, and the second group, the eighth group, the ninth group, the tenth group, the eleventh group, At least one metal selected from Group 12, Group 13, and Group 14 is more preferable, and it is particularly preferable that it is included as a main component.

Examples of the metal include copper, silver, gold, platinum, palladium, nickel, tin, cobalt, rhodium, iridium, iron, ruthenium, osmium, manganese, molybdenum, tungsten, niobium, tantel, titanium, bismuth, antimony, and lead. And alloys thereof. Among these, silver and an alloy with silver are particularly preferable in terms of excellent conductivity.
Examples of the metal used in the alloy with silver include platinum, osmium, palladium, iridium, tin, bismuth, and nickel. These may be used alone or in combination of two or more.

There is no restriction | limiting in particular as a shape of the said metal nanowire, According to the objective, it can select suitably, For example, it can take arbitrary shapes, such as a column shape, a rectangular parallelepiped shape, and the column shape from which a cross section becomes a polygon. In applications where high transparency is required, it is preferable that the column shape or the shape of a columnar polygon having a polygonal cross section is rounded.
Here, the cross-sectional shape of the metal nanowires can be examined by applying a metal nanowire aqueous dispersion on a substrate and observing a cross-section sliced by a microtome with a transmission electron microscope (TEM).

The average minor axis length (sometimes referred to as “average minor axis length” or “average diameter”) of the metal nanowire is 5 to 50 nm, preferably 5 to 25 nm, and more preferably 5 to 20 nm.
If the average minor axis length is less than 5 nm, the oxidation resistance may deteriorate and the durability may deteriorate. On the other hand, when the average minor axis length is 50 nm or more, scattering of the metal nanowires increases, and the haze value of the conductive film may increase. In particular, by setting the average minor axis length to 25 nm or less, the scattering of the metal nanowires can be reduced, and the haze value of the conductive film is greatly improved (reduced). A touch panel using a conductive film having a small haze can eliminate the pattern appearance (bone appearance) of the conductive film and improve the visibility of the touch panel. The haze value of the conductive film is preferably less than 2.5%, and particularly preferably less than 1.5% from the viewpoint of visibility.

The average minor axis length of the metal nanowires was determined by observing 300 metal nanowires using a transmission electron microscope (TEM; manufactured by JEOL Ltd., JEM-2000FX). The average minor axis length was determined. In addition, the shortest axis length when the short axis of the metal nanowire is not circular is the shortest axis.

The average major axis length of the metal nanowire (sometimes referred to as “average major axis length” or “average length”) is preferably 5 μm or more, more preferably 5 μm to 40 μm, and more preferably 5 μm to 30 μm. Is more preferable.
If the average major axis length is less than 5 μm, it may be difficult to form a dense network and sufficient conductivity may not be obtained. If it exceeds 40 μm, the metal nanowires are too long and manufactured. Sometimes entangled and agglomerates may occur during the manufacturing process.
The average major axis length of the metal nanowires is observed, for example, using a transmission electron microscope (TEM; manufactured by JEOL Ltd., JEM-2000FX), and 300 metal nanowires are observed. The average major axis length was determined. In addition, when the said metal nanowire was bent, the circle | round | yen which makes it an arc was considered and the value calculated from the radius and curvature was made into the major axis length.

The coefficient of variation of the short axis length of the metal nanowire is preferably 50% or less, more preferably 40% or less, and particularly preferably 30% or less.
The coefficient of variation is obtained by measuring the short axis length (diameter) of 300 nanowires randomly selected from the electron microscope (TEM) image, and calculating the standard deviation and the average value for the 300 nanowires. It was.

The metal nanowire is not particularly limited and may be produced by any method, but is preferably produced by reducing metal ions in a solvent in which a halogen compound and a dispersant are dissolved as follows. Moreover, after forming metal nanowire, it is preferable to perform a desalting process by a conventional method from a viewpoint of dispersibility and the temporal stability of an electroconductive area.
In addition, as a method for producing metal nanowires, JP2009-215594A, JP2009-242880A, JP2009-299162A, JP2010-84173A, and JP2010-86714A are disclosed. Etc. can be used.

The solvent used for the production of the metal nanowire is preferably a hydrophilic solvent, and examples thereof include water, alcohols, polyhydric alcohols, ethers and ketones, and these may be used alone. In addition, two or more kinds may be used in combination. Examples of alcohols include methanol, ethanol, normal propanol, isopropanol, and butanol. Examples of the polyhydric alcohols include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol and the like. Examples of ethers include dioxane and tetrahydrofuran. Examples of ketones include acetone and methyl ethyl ketone. When heating, the heating temperature is preferably 250 ° C. or lower, more preferably 20 ° C. or higher and 200 ° C. or lower, further preferably 30 ° C. or higher and 180 ° C. or lower, and 40 ° C. or higher and 170 ° C. as long as the boiling point of the solvent used is not exceeded. The following is particularly preferable, and 50 ° C or higher and 100 ° C or lower is most preferable. The boiling point means a temperature at which the vapor pressure of the reaction solvent becomes equal to the pressure in the reaction vessel. It is preferable to set the temperature to 20 ° C. or higher because formation of metal nanowires is promoted and manufacturing process time can be shortened. Moreover, by setting it as 250 degrees C or less, the monodispersity of the short-axis length and long-axis length of metal nanowire improves, and it is suitable from a transparency and electroconductive viewpoint. If necessary, the temperature may be changed during the manufacturing process of the metal nanowires, and changing the temperature in the middle is effective in controlling nucleation, suppressing renucleation, and improving monodispersity by promoting selective growth. There may be.

The heating is preferably performed by adding a reducing agent.
The reducing agent is not particularly limited and can be appropriately selected from those usually used. For example, borohydride metal salt, aluminum hydride salt, alkanolamine, aliphatic amine, heterocyclic amine, Aromatic amines, aralkylamines, alcohols, polyhydric alcohols, organic acids, reducing sugars, sugar alcohols, sodium sulfite, hydrazine compounds, dextrin, hydroquinone, hydroxylamine, glutathione and the like can be mentioned. Among these, reducing sugars, sugar alcohols as derivatives thereof, and polyhydric alcohols are particularly preferable. Depending on the reducing agent, there is a compound that functions as a dispersant or a solvent as a function, and can be preferably used in the same manner.

In producing the metal nanowire, it is preferable to add a dispersant and a halogen compound or metal halide fine particles.
The timing of addition of the dispersant may be before the addition of the reducing agent, at the same time as the addition of the reducing agent, or after the addition of the reducing agent, before the addition of the metal ion or metal halide fine particles, or before the addition of the metal ion or halogen. It may be performed simultaneously with the addition of metal halide fine particles or after addition of metal ions or metal halide fine particles.

The step of adding the dispersant may be added before the particles are prepared and may be added in the presence of the dispersed polymer, or may be added after the particles are prepared in order to control the dispersion state. When dividing the addition of the dispersant into two or more steps, the amount needs to be changed depending on the short axis length and the long axis length of the metal nanowires required. This is because the amount of dispersant added affects the amount and size of the metal particles that are the core of the metal nanowire, and the amount and size of the metal particles that are the core of the metal nanowire are the short axis of the metal nanowire. This is considered to be due to the influence on the length and the long axis length.
Examples of the dispersant include amino group-containing compounds, thiol group-containing compounds, sulfide group-containing compounds, amino acids or derivatives thereof, peptide compounds, polysaccharides, polysaccharide-derived natural polymers, synthetic polymers, or these. And polymers such as gels. Among these, various polymer compounds used as a dispersant are compounds included in the polymer described later.

Examples of the polymer suitably used as a dispersant include gelatin, polyvinyl alcohol, methyl cellulose, hydroxypropyl cellulose, polyalkylene amine, polyalkylene amine, partial alkyl esters of polyacrylic acid, polyvinyl pyrrolidone, and polyvinyl pyrrolidone structures, which are protective colloidal polymers. A polymer having a hydrophilic group such as a copolymer containing, polyacrylic acid having an amino group or a thiol group, is preferably mentioned.
The polymer used as the dispersant has a weight average molecular weight (Mw) measured by GPC method of preferably 3000 or more and 300000 or less, more preferably 5000 or more and 100000 or less.
For the structure of the compound that can be used as the dispersant, for example, the description of “Encyclopedia of Pigments” (edited by Seijiro Ito, published by Asakura Shoin Co., Ltd., 2000) can be referred to.
The shape of the metal nanowire obtained by the kind of dispersing agent to be used can be changed.

The halogen compound is not particularly limited as long as it is a compound containing bromine, chlorine, or iodine, and can be appropriately selected according to the purpose. For example, sodium bromide, sodium chloride, sodium iodide, potassium iodide Compounds that can be used in combination with alkali halides such as potassium bromide, potassium chloride, potassium iodide and the following dispersants are preferred.
Some halogen compounds may function as a dispersant, but can be preferably used in the same manner.
As an alternative to the halogen compound, silver halide fine particles may be used, or both a halogen compound and silver halide fine particles may be used.

Further, a single substance having both functions may be used as the dispersant and the halogen compound. That is, by using a halogen compound having a function as a dispersant, the functions of both the dispersant and the halogen compound are expressed with one compound.
Examples of the halogen compound having a function as a dispersant include, for example, hexadecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, hexadecyltrimethylammonium iodide, dodecyltrimethyl containing amino group and bromide ion or chloride ion and iodide ion. Ammonium bromide, dodecyltrimethylammonium chloride, dodecyltrimethylammonium iodide, stearyltrimethylammonium bromide, stearyltrimethylammonium chloride, stearyltrimethylammonium iodide, decyltrimethylammonium bromide, decyltrimethylammonium chloride, decyltrimethylammonium iodide, dimethyldistearylammonium Bromide Dimethyl distearyl ammonium chloride, dimethyl distearyl ammonium iodide, dilauryl dimethyl ammonium bromide, dilauryl dimethyl ammonium chloride, dilauryl dimethyl ammonium iodide, dimethyl dipalmityl ammonium bromide, dimethyl dipalmityl ammonium chloride, dimethyl dipalmityl Ammonium iodide, tetramethylammonium bromide, tetramethylammonium chloride, tetramethylammonium iodide, tetraethylammonium bromide, tetraethylammonium chloride, tetraethylammonium iodide, tetrapropylammonium bromide, tetrapropylammonium chloride, tetrapropylammonium iodide Tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium iodide, methyltriethylammonium chloride, methyltriethylammonium bromide, methyltriethylammonium iodide, dimethyldiethylammonium bromide, dimethyldiethylammonium chloride, dimethyldiethylammonium iodide, ethyltrimethyl Ammonium bromide, ethyltrimethylammonium chloride, ethyltrimethylammonium iodide, hexadecyldimethylammonium bromide, hexadecyldimethylammonium chloride, hexadecyldimethylammonium iodide, dodecyldimethylammonium bromide, dodecyldimethylammonium chloride, Examples include dodecyldimethylammonium iodide, stearyldimethylammonium bromide, stearyldimethylammonium chloride, stearyldimethylammonium iodide, decyldimethylammonium bromide, decyldimethylammonium chloride, decyldimethylammonium iodide. These may be used alone or in combination of two or more.

There are no particular restrictions on the desalting process for removing unnecessary components such as organic substances and inorganic ions other than metal nanowires. Sedimentation of metal nanowires by centrifugation, etc., and subsequent removal of the supernatant, filtrate by ultrafiltration In addition, dialysis, gel filtration, etc. can be used. Moreover, in order to remove unnecessary components, it is possible to add a chemical that promotes elution of unnecessary components and perform desalting treatment. Examples of such an agent that promotes elution of unnecessary components include ammonia for silver halides such as silver chloride, chelating agents for various metal ions, and disodium ethylenediaminetetraacetate.

The metal nanowire preferably contains as little inorganic ions as possible, such as alkali metal ions, alkaline earth metal ions, and halide ions. The electrical conductivity when the metal nanowire is an aqueous dispersion is preferably 1 mS / cm or less, more preferably 0.1 mS / cm or less, and even more preferably 0.05 mS / cm or less.
The viscosity at 20 ° C. when the metal nanowires are dispersed in water is preferably 0.5 mPa · s to 100 mPa · s, more preferably 1 mPa · s to 50 mPa · s.

The aspect ratio of the metal nanowire is not particularly limited as long as it is 10 or more, and can be appropriately selected according to the purpose. More preferred is 10,000 to 100,000. The aspect ratio generally means the ratio between the long side and the short side of a fibrous material (ratio of average major axis length / average minor axis length).
There is no restriction | limiting in particular as a measuring method of the said aspect ratio, According to the objective, it can select suitably, For example, the method etc. which measure with an electron microscope etc. are mentioned.
When measuring the aspect ratio of the metal nanowire with an electron microscope, it is only necessary to confirm whether the aspect ratio of the metal nanowire is 10 or more with one field of view of the electron microscope. Moreover, the aspect ratio of the whole metal nanowire can be estimated by measuring the average major axis length and the average minor axis length of the metal nanowire separately.
In addition, when the said metal nanowire is tube shape (hollow fiber), the outer diameter of this tube-shaped metal nanowire is used as a diameter for calculating the said aspect ratio.

Further, the metal nanowire having an aspect ratio of 10 or more is preferably contained in the coating liquid for all patterns transparent conductive film in a volume ratio of 5% or more, more preferably 50% or more, and more preferably 80% or more. It is particularly preferred that it be included. Hereinafter, the ratio of these metal nanowires may be referred to as “the ratio of metal nanowires”.
If the ratio of the metal nanowires is less than 5%, the conductive material that contributes to the conductivity may decrease and the conductivity may decrease. At the same time, a voltage concentration may occur because a dense network cannot be formed. , Durability may be reduced. In addition, particles having a shape other than metal nanowires are not preferable because they do not greatly contribute to conductivity and have absorption. In particular, when the particles other than the metal conductive fibers are metal and the plasmon absorption such as a spherical shape is strong, the transparency may be deteriorated.

By setting the aspect ratio to 10 or more, a network in which metal nanowires are in contact with each other is easily formed, and a conductive layer having high conductivity can be easily obtained. Further, by setting the aspect ratio to 100,000 or less, for example, in a coating liquid when a conductive layer is provided on a substrate by coating, stable coating without risk of entanglement and aggregation of metal nanowires. Since a liquid is obtained, manufacture becomes easy.
In addition, when the ratio of the metal nanowire is less than 5%, the conductive material that contributes to conductivity may decrease and conductivity may decrease, and at the same time, a dense network cannot be formed. May occur and durability may be reduced. In addition, particles having a shape other than metal nanowires are not preferable because they do not greatly contribute to conductivity and have absorption. In particular, in the case of a metal, when the plasmon absorption such as a spherical shape is strong, the transparency may be deteriorated.

Here, the ratio of the metal nanowire is, for example, when the metal nanowire is a silver nanowire, the silver nanowire aqueous dispersion is filtered to separate the silver nanowire from the other particles. The ratio of metal nanowires can be determined by measuring the amount of silver remaining on the filter paper and the amount of silver transmitted through the filter paper using an ICP emission analyzer. By observing the metal nanowires remaining on the filter paper with a TEM, observing the average minor axis length of 300 metal nanowires, and examining the distribution thereof, the average minor axis length is 200 nm or less, and the average It confirms that it is a metal nanowire whose major axis length is 1 micrometer or more. The filter paper measures the longest axis of particles other than metal nanowires having an average minor axis length of 200 nm or less and an average major axis length of 1 μm or more in a TEM image, and more than twice the longest axis. It is preferable to use a metal nanowire having a length equal to or shorter than the shortest length of the major axis of the metal nanowire.

Here, the average minor axis length and the average major axis length of the metal nanowire can be obtained by observing a TEM image or an optical microscope image using, for example, a transmission electron microscope (TEM) or an optical microscope. In the present invention, the average minor axis length and the average major axis length of the metal nanowire are obtained by observing 300 metal nanowires with a transmission electron microscope (TEM) and calculating the average value. is there.

The coating amount of the metal nanowires is preferably patterned transparent conductive film in 0.001 ~ 0.1g / cm ^2, more preferably ^{0.002 ~ 0.05g / cm 2, 0.003} ~ 0.04g / cm 2 Is particularly preferred.

Composition for forming transparent conductive film:
The composition for transparent conductive film formation which forms the said pattern transparent conductive film may be a photosensitive composition. The photosensitive composition may be negative or positive. Hereinafter, examples of a composition containing at least a photosensitive composition, a sol-gel cured product, and a polymer that can be used for forming a patterned transparent conductive film will be described, but the present invention is not limited to the following examples.

For the formation of the patterned transparent conductive film, for example, (1) a photosensitive composition containing at least a binder and a photopolymerizable composition as a matrix component together with the metal nanowires, (2) a sol-gel cured product, (3 ) A composition containing at least a polymer can be used.
In the present invention, the mass ratio of the matrix component (all components excluding the metal nanowire and the solvent contained in the pattern transparent conductive film coating solution) to the metal nanowire is 0.5 to 15 (more preferably 1.0 to 12). Particularly preferred is 2.0 to 10).
When the mass ratio is less than 0.5, the matrix component is small, the adhesion of the metal nanowires to the substrate surface is weak, and the film strength may be weak. When the mass ratio exceeds 15, the pattern is transparent. The surface resistance value of the conductive film may increase.

binder:
The binder is a linear organic high molecular polymer, and at least one group that promotes alkali solubility in a molecule (preferably a molecule having an acrylic copolymer or a styrene copolymer as a main chain) ( For example, it can be appropriately selected from alkali-soluble resins having a carboxyl group, a phosphoric acid group, a sulfonic acid group, and the like.
Among these, those that are soluble in an organic solvent and soluble in an aqueous alkali solution are preferable, and those that have an acid-dissociable group and become alkali-soluble when the acid-dissociable group is dissociated by the action of an acid are particularly preferable. preferable.
Here, the acid dissociable group represents a functional group that can dissociate in the presence of an acid.

For the production of the binder, for example, a known radical polymerization method can be applied. Polymerization conditions such as temperature, pressure, type and amount of radical initiator, type of solvent, etc. when producing an alkali-soluble resin by the radical polymerization method can be easily set by those skilled in the art, and the conditions are determined experimentally. Can be determined.

As the linear organic polymer, a polymer having a carboxylic acid in the side chain is preferable.
Examples of the polymer having a carboxylic acid in the side chain include, for example, JP-A-59-44615, JP-B-54-34327, JP-B-58-12777, JP-B-54-25957, JP-A-59-53836, As described in JP-A-59-71048, methacrylic acid copolymer, acrylic acid copolymer, itaconic acid copolymer, crotonic acid copolymer, maleic acid copolymer, partial ester Maleic acid copolymers, acidic cellulose derivatives having a carboxylic acid in the side chain, polymers obtained by adding an acid anhydride to a polymer having a hydroxyl group, and further having a (meth) acryloyl group in the side chain A high molecular polymer is also mentioned as a preferable polymer.

Among these, benzyl (meth) acrylate / (meth) acrylic acid copolymers and multi-component copolymers composed of benzyl (meth) acrylate / (meth) acrylic acid / other monomers are particularly preferable.
Furthermore, a high molecular polymer having a (meth) acryloyl group in the side chain and a multi-component copolymer composed of (meth) acrylic acid / glycidyl (meth) acrylate / other monomers are also useful. The polymer can be used by mixing in an arbitrary amount.

In addition to the above, 2-hydroxypropyl (meth) acrylate / polystyrene macromonomer / benzyl methacrylate / methacrylic acid copolymer, 2-hydroxy-3-phenoxypropyl acrylate / polymethyl described in JP-A-7-140654 Methacrylate macromonomer / benzyl methacrylate / methacrylic acid copolymer, 2-hydroxyethyl methacrylate / polystyrene macromonomer / methyl methacrylate / methacrylic acid copolymer, 2-hydroxyethyl methacrylate / polystyrene macromonomer / benzyl methacrylate / methacrylic acid copolymer Coalescence, etc.

As the specific structural unit in the alkali-soluble resin, (meth) acrylic acid and other monomers copolymerizable with the (meth) acrylic acid are suitable.

Examples of other monomers copolymerizable with the (meth) acrylic acid include alkyl (meth) acrylates, aryl (meth) acrylates, and vinyl compounds. In these, the hydrogen atom of the alkyl group and aryl group may be substituted with a substituent.
Examples of the alkyl (meth) acrylate or aryl (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, and pentyl (meth). Acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, tolyl (meth) acrylate, naphthyl (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentanyl (meta ) Acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, glycidyl methacrylate, tetrahydrofurfuryl methacrylate, Polymethyl methacrylate macromonomer, and the like. These may be used individually by 1 type and may use 2 or more types together.

Examples of the vinyl compound include styrene, α-methylstyrene, vinyl toluene, acrylonitrile, vinyl acetate, N-vinyl pyrrolidone, polystyrene macromonomer, CH ₂ = CR ¹ R ² [where R ¹ is a hydrogen atom or a carbon number. R 1 represents an alkyl group having 1 to 5 carbon atoms, and R ² represents an aromatic hydrocarbon ring having 6 to 10 carbon atoms. ] And the like. These may be used individually by 1 type and may use 2 or more types together.

The weight average molecular weight of the binder is preferably from 1,000 to 500,000, more preferably from 3,000 to 300,000, and even more preferably from 5,000 to 200,000, from the viewpoints of alkali dissolution rate, film physical properties and the like. .
Here, the weight average molecular weight is measured by a gel permeation chromatography method (GPC method) and can be determined using a standard polystyrene calibration curve.

The content of the binder is preferably 5% by mass to 90% by mass, more preferably 10% by mass to 85% by mass, based on the total mass of the solid content of the photopolymerizable composition containing the metal nanowires. Preferably, 20% by mass to 80% by mass is more preferable. When the content is within the preferable range, both developability and conductivity of the metal nanowire can be achieved.

Photopolymerizable composition:
The photopolymerizable composition means a compound that imparts a function of forming an image by exposure to the patterned transparent conductive film or gives a trigger for the function. The basic component includes (a) an addition-polymerizable unsaturated compound and (b) a photopolymerization initiator that generates radicals when irradiated with light.

[(A) Addition polymerizable unsaturated compound]
The component (a) addition-polymerizable unsaturated compound (hereinafter also referred to as “polymerizable compound”) is a compound that undergoes an addition-polymerization reaction in the presence of a radical to form a polymer, and usually has a molecular end. A compound having at least one, more preferably two or more, more preferably four or more, still more preferably six or more ethylenically unsaturated double bonds is used.
These have chemical forms such as monomers, prepolymers, i.e. dimers, trimers and oligomers, or mixtures thereof.
Various kinds of such polymerizable compounds are known, and they can be used as the component (a).
Among these, particularly preferred polymerizable compounds are, from the viewpoint of film strength, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth). Acrylates are particularly preferred.

The content of component (a) is preferably 2.6% by mass or more and 37.5% by mass or less based on the total mass of the solid content of the photopolymerizable composition containing the metal nanowires described above. More preferably, it is 0.0 mass% or more and 20.0 mass% or less.

[(B) Photopolymerization initiator]
The photopolymerization initiator of component (b) is a compound that generates radicals when irradiated with light. Examples of such photopolymerization initiators include compounds that generate acid radicals that ultimately become acids upon irradiation with light, and compounds that generate other radicals. Hereinafter, the former is referred to as “photoacid generator”, and the latter is referred to as “photoradical generator”.
-Photoacid generator-
Photoacid generator includes photoinitiator for photocationic polymerization, photoinitiator for photoradical polymerization, photodecoloring agent for dyes, photochromic agent, irradiation of actinic ray or radiation used for micro resist, etc. Thus, known compounds that generate acid radicals and mixtures thereof can be appropriately selected and used.

Such a photoacid generator is not particularly limited and may be appropriately selected depending on the intended purpose. For example, quinonediazide compound, triazine having at least one di- or tri-halomethyl group, or 1,3,4 -Oxadiazole, naphthoquinone-1,2-diazide-4-sulfonyl halide, diazonium salt, phosphonium salt, sulfonium salt, iodonium salt, imide sulfonate, oxime sulfonate, diazodisulfone, disulfone, o-nitrobenzyl sulfonate, etc. . Among these, imide sulfonate, oxime sulfonate, and o-nitrobenzyl sulfonate, which are compounds that generate sulfonic acid, are particularly preferable.
Further, a group in which an acid radical is generated by irradiation with actinic rays or radiation, or a compound in which a compound is introduced into the main chain or side chain of the resin, for example, US Pat. No. 3,849,137, German Patent 3914407. JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038, JP-A-63-163452, JP-A-62-153853 And compounds described in JP-A-63-146029, etc. can be used.
Furthermore, compounds described in each specification such as US Pat. No. 3,779,778 and European Patent 126,712 can also be used as an acid radical generator.

As the triazine compound, for example, compounds described in JP2011-018636A and JP2011-254046A can be used.

In the present invention, among the photoacid generators, compounds that generate sulfonic acid are preferable, and the following oxime sulfonate compounds are particularly preferable from the viewpoint of high sensitivity.

When a compound having a 1,2-naphthoquinonediazide group is used as the quinonediazide compound, high sensitivity and good developability are obtained.
Of the quinonediazide compounds, compounds in which D of the compounds shown below are each independently a hydrogen atom or a 1,2-naphthoquinonediazide group are preferred from the viewpoint of high sensitivity.

-Photoradical generator-
The photoradical generator is a compound that has a function of generating radicals by directly absorbing light or being photosensitized to cause a decomposition reaction or a hydrogen abstraction reaction. The photo radical generator is preferably a compound having absorption in the wavelength region of 300 nm to 500 nm.
As such a photo radical generator, many compounds are known. For example, triazine compounds, carbonyl compounds, ketal compounds, benzoin compounds, acridine compounds, as described in JP-A-2008-268884, Examples thereof include organic peroxide compounds, azo compounds, coumarin compounds, azide compounds, metallocene compounds, hexaarylbiimidazole compounds, organic boric acid compounds, disulfonic acid compounds, oxime ester compounds, and acylphosphine (oxide) compounds. These can be appropriately selected according to the purpose. Among these, benzophenone compounds, acetophenone compounds, hexaarylbiimidazole compounds, oxime ester compounds, and acylphosphine (oxide) compounds are particularly preferable from the viewpoint of exposure sensitivity.

As the photo radical generator, for example, the photo radical generators described in JP 2011-018636 A and JP 2011-254046 A can be used.

A photoinitiator may be used individually by 1 type and may use 2 or more types together, The content is based on the total mass of solid content of the photopolymerizable composition containing metal nanowire, The content is preferably 0.1% by mass to 50% by mass, more preferably 0.5% by mass to 30% by mass, and still more preferably 1% by mass to 20% by mass. In such a numerical range, when a pattern including a conductive region and a non-conductive region described later is formed on the conductive layer, good sensitivity and pattern formability can be obtained.

Other additives other than the above components include, for example, chain transfer agents, crosslinking agents, dispersants, solvents, surfactants, antioxidants, sulfurization inhibitors, metal corrosion inhibitors, viscosity modifiers, preservatives, and the like. Various additives are mentioned.

[Chain transfer agent]
The chain transfer agent is used for improving the exposure sensitivity of the photopolymerizable composition. Examples of such chain transfer agents include N, N-dialkylaminobenzoic acid alkyl esters such as N, N-dimethylaminobenzoic acid ethyl ester, 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, and 2-mercaptobenzoic acid. Complexes such as imidazole, N-phenylmercaptobenzimidazole, 1,3,5-tris (3-mercaptobutyloxyethyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione Aliphatic polyfunctional mercapto such as mercapto compounds having a ring, pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptobutyrate), 1,4-bis (3-mercaptobutyryloxy) butane Compound etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together.

The content of the chain transfer agent is preferably 0.01% by mass to 15% by mass, preferably 0.1% by mass to 10% by mass, based on the total mass of the solid content of the photopolymerizable composition containing the metal nanowires. % Is more preferable, and 0.5% by mass to 5% by mass is still more preferable.

[Crosslinking agent]
The crosslinking agent is a compound that forms a chemical bond by free radical or acid and heat and cures the patterned transparent conductive film, and is substituted with at least one group selected from, for example, a methylol group, an alkoxymethyl group, and an acyloxymethyl group. Melamine compound, guanamine compound, glycoluril compound, urea compound, phenol compound or phenol ether compound, epoxy compound, oxetane compound, thioepoxy compound, isocyanate compound, azide compound, methacryloyl group or And compounds having an ethylenically unsaturated group containing an acryloyl group. Among these, an epoxy compound, an oxetane compound, and a compound having an ethylenically unsaturated group are particularly preferable in terms of film properties, heat resistance, and solvent resistance.
Moreover, the said oxetane resin can be used individually by 1 type or in mixture with an epoxy resin. In particular, when used in combination with an epoxy resin, the reactivity is high, which is preferable from the viewpoint of improving film properties.
In addition, when using the compound which has an ethylenically unsaturated double bond group as a crosslinking agent, the said crosslinking agent is also included by the said polymeric compound, The content is content of the polymeric compound in this invention. Should be included.
The content of the crosslinking agent is preferably 1 part by weight to 250 parts by weight, preferably 3 parts by weight to 200 parts by weight, when the total weight of the solid content of the photopolymerizable composition containing the metal nanowire is 100 parts by weight. Is more preferable.

[Dispersant]
A dispersing agent is used in order to disperse | distribute, preventing that the above-mentioned metal nanowire in a photopolymerizable composition aggregates. The dispersant is not particularly limited as long as the metal nanowires can be dispersed, and can be appropriately selected according to the purpose. For example, a commercially available dispersant can be used as a pigment dispersant, and a polymer dispersant having a property of adsorbing to metal nanowires is particularly preferable. Examples of such a polymer dispersant include polyvinyl pyrrolidone, BYK series (manufactured by Big Chemie), Solsperse series (manufactured by Nippon Lubrizol Co., Ltd.), and Ajisper series (manufactured by Ajinomoto Co., Inc.).
In addition, when a polymer dispersant is added as a dispersant other than that used in the production of the metal nanowires, the polymer dispersant is also included in the binder, and the content thereof is as described above. It should be considered that it is included in the content of the binder.
The content of the dispersant is preferably 0.1 to 50 parts by weight, more preferably 0.5 to 40 parts by weight, and particularly preferably 1 to 30 parts by weight with respect to 100 parts by weight of the binder. .
By setting the content of the dispersant to 0.1 parts by mass or more, aggregation of metal nanowires in the dispersion is effectively suppressed, and by setting the content to 50 parts by mass or less, a stable liquid film in the coating process Is preferable, and the occurrence of uneven coating is suppressed.

[solvent]
The solvent is a component used to form a coating solution for forming a composition containing the metal nanowire and the specific alkoxide compound and the photopolymerizable composition on the surface of the substrate in the form of a film. It can be appropriately selected according to, for example, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, ethyl 3-ethoxypropionate, methyl 3-methoxypropionate, ethyl lactate, 3-methoxybutanol, water, 1-methoxy- Examples include 2-propanol, isopropyl acetate, methyl lactate, N-methylpyrrolidone (NMP), γ-butyrolactone (GBL), propylene carbonate, and the like. This solvent may also serve as at least a part of the solvent of the metal nanowire dispersion described above. These may be used individually by 1 type and may use 2 or more types together.
The solid content concentration of the coating solution containing such a solvent is preferably contained in the range of 0.1% by mass to 20% by mass.

[Metal corrosion inhibitor]
It is preferable to contain the metal nanowire metal corrosion inhibitor. There is no restriction | limiting in particular as such a metal corrosion inhibitor, Although it can select suitably according to the objective, For example, thiols, azoles, etc. are suitable.
By containing a metal corrosion inhibitor, a rust prevention effect can be exhibited, and the deterioration of the conductivity and transparency of the transparent conductive laminate over time can be suppressed. The metal corrosion inhibitor is added to the composition for forming a transparent conductive film in a state dissolved in a suitable solvent, or added as a powder, or after forming a conductive film with a coating liquid for a patterned transparent conductive film, which will be described later, this is subjected to metal corrosion. It can be applied by dipping in an inhibitor bath.
When a metal corrosion inhibitor is added, it is preferable to contain 0.5% by mass to 10% by mass with respect to the metal nanowires.

As the other matrix, it is possible to use a polymer compound as a dispersant used in the production of the above-described metal nanowires as at least a part of components constituting the matrix.

For the formation of the transparent conductive film, a composition containing at least a sol-gel cured product as a matrix component can be used together with the metal nanowires.

<Sol-gel cured product>
The sol-gel cured product is obtained by hydrolyzing and polycondensing an alkoxide compound of an element selected from the group consisting of Si, Ti, Zr and Al (hereinafter also referred to as “specific alkoxide compound”), and further heating and drying as desired. Is obtained.
[Specific alkoxide compound]
The specific alkoxide compound is preferably a compound represented by the following general formula (I) because it is easily available.
M ¹ (OR ¹ ) _a R ² _4-a (I)
(In the general formula (I), M ¹ represents an element selected from Si, Ti and Zr, R ¹ and R ² each independently represents a hydrogen atom or a hydrocarbon group, and a represents an integer of 2 to 4 Show.)

As each hydrocarbon group of R ¹ and R ² in the general formula (I), an alkyl group or an aryl group is preferable.
The carbon number in the case of showing an alkyl group is preferably 1 to 18, more preferably 1 to 8, and still more preferably 1 to 4. Moreover, when showing an aryl group, a phenyl group is preferable.
The alkyl group or aryl group may have a substituent, and examples of the substituent that can be introduced include a halogen atom, an amino group, an alkylamino group, and a mercapto group.
The compound represented by the general formula (I) is a low molecular compound and preferably has a molecular weight of 1000 or less.

Specific examples of the compound represented by the general formula (I) are described in, for example, JP-A-2010-064474.

When the sol-gel cured product is used as a matrix of the conductive layer in the present invention, the ratio of the specific alkoxide compound to the metal nanowire, that is, the mass ratio of the specific alkoxide compound / metal nanowire is 0.25 / 1 to 30 / Used in the range of 1. When the mass ratio is less than 0.25 / 1, the transparency is inferior, and at the same time, the conductive layer is inferior in at least one of wear resistance, heat resistance, moist heat resistance and flex resistance. On the other hand, when the mass ratio is larger than 30/1, the conductive layer is inferior in conductivity and flex resistance.
The mass ratio is more preferably in the range of 0.5 / 1 to 20/1, more preferably in the range of 1/1 to 15/1, and most preferably in the range of 2/1 to 8/1. High conductivity and high transparency It is preferable because it can stably obtain a conductive material having high properties (total light transmittance and haze), excellent wear resistance, heat resistance and moist heat resistance, and excellent flex resistance.

For the formation of the conductive film, a composition containing at least a polymer as a matrix component can be used together with the metal nanowires.
Synthetic polymers and natural polymers are included as the polymers. Examples of the synthetic polymers include polyester, polyimide, polyacryl, polyvinylon, polyethylene, polypropylene, polystyrene, polyvinyl chloride, methacrylic resin, fluorine-based resin, and phenol. Examples thereof include resins, melamine resins, silicone resins, synthetic rubbers, and latexes thereof. Examples of the natural polymer include cellulosic resins and natural rubber.

If necessary, a protective layer made of a protective coating material may be provided on the conductive film.
Protective coating materials include crosslinkers, polymerization initiators, stabilizers (eg, antioxidants and UV stabilizers for prolonging product life, and polymerization inhibitors for improving shelf life), surfactants, and the like You may include what has a special effect. The protective coating material may further include a corrosion inhibitor that prevents corrosion of the metal nanowires.

The method for forming the protective layer is not particularly limited as long as it is a known wet coating method. Specifically, spray coating, bar coating, roll coating, die coating, ink jet coating, screen coating, dip coating and the like can be mentioned.

When forming the protective layer while impregnating the pattern transparent conductive film with the protective coating material, if the film thickness of the protective layer after application and drying is too thin relative to the pattern transparent conductive film before application, the abrasion resistance and abrasion resistance The function as a protective layer such as property and weather resistance is lowered, and if it is too thick, the contact resistance as a conductor increases.

When the thickness of the patterned transparent conductive film is 50 to 150 nm, the coating for the protective layer is preferably 30 to 150 nm after coating and drying. In consideration of the thickness, the surface resistivity, haze, and the like can be adjusted to achieve predetermined values. 40 to 175 nm is more preferable, and 50 to 150 nm is particularly preferable. Although the film thickness after drying of the coating material for the protective layer depends on the film thickness of the pattern transparent conductive film, the protective function by the protective layer tends to work better when the film thickness is 30 nm or more. When it is thick, it tends to be able to ensure better conductive performance.

Application method of transparent conductive film:
An example of a transparent conductive film coating method (formation method) for forming the pattern transparent conductive film is as follows, but is not limited to the following example.
First, a coating liquid for a patterned transparent conductive film is prepared. The coating solution comprises at least a metal nanowire having an average minor axis length of 5 to 50 nm and a matrix component (preferably a binder and a photosensitive compound, a sol-gel cured product, or a polymer (for forming a transparent conductive film). The composition) and, if necessary, other components) can be mixed and prepared by a conventional method.

Next, the pattern transparent conductive film coating solution is applied to a substrate surface such as a glass plate or a film. The method for applying is not particularly limited and can be appropriately selected depending on the purpose. For example, spray coating method, air brush method, curtain spray method, dip coating method, roller coating method, spin coating method, ink jet method, Examples include an extrusion method.

The coating amount is preferably such that the metal nanowires are 0.005 to 0.5 g / m ² .

Next, the pattern transparent conductive film coating solution is applied onto a substrate to form a coating layer, and then exposed and cured.
There is no restriction | limiting in particular as an exposure method, Although it can select suitably according to a use etc., the exposure method using an ultraviolet irradiation device, a ultraviolet irradiation lamp, etc. is preferable.

You may implement the process of processing the transparent conductive film after the said exposure (after hardening) with an alkaline solution (alkali treatment).
The alkali contained in the alkaline solution is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include tetramethylammonium hydroxide, tetraethylammonium hydroxide, 2-hydroxyethyltrimethylammonium hydroxide, sodium carbonate, Examples thereof include sodium hydrogen carbonate, potassium carbonate, potassium hydrogen carbonate, sodium hydroxide, potassium hydroxide and the like.

In the alkaline solution, methanol, ethanol, or a surfactant may be added as necessary. As the surfactant, for example, an anionic surfactant, a cationic surfactant, and a nonionic surfactant can be selected and used. Among these, the addition of nonionic polyoxyethylene alkyl ether is particularly preferable because the resolution becomes high.

The alkali treatment is not particularly limited and may be appropriately selected depending on the intended purpose. For example, any of dip development, paddle development, and shower development can be used.
By performing the alkali treatment, the conductivity of the patterned transparent conductive film can be increased.
The immersion time of the alkaline solution is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 10 seconds to 5 minutes.

Formation of pattern transparent conductive film:
In the present invention, a patterned transparent conductive film is formed by the following method.

Formation of the pattern transparent conductive film exposes and develops the conductive film, and includes a pattern exposure process and a development process, and further includes other processes as necessary.

The conductive film is patterned so as to have a desired pattern including a conductive area and a non-conductive area, and the conductive pattern member according to the present invention is manufactured. Examples of such a patterning method include the following methods. In the following description, the conductive film before patterning is also referred to as “non-patterned conductive layer”.
When the matrix of the conductive film is non-photosensitive, it is patterned by the following methods (1) to (2).
(1) A photoresist layer is provided on a non-patterned conductive layer, and a desired pattern exposure and development are performed on the photoresist layer to form the patterned resist (etching mask material). Etch the metal nanowires in the conductive layer in areas not protected by resist by wire processes with etchable etchants or dry processes such as reactive ion etching to break or disappear Patterning method. This method is described, for example, in JP-T-2010-507199 (particularly, paragraphs 0212 to 0217).
(2) In a desired region on the non-patterned conductive layer, a photocurable resin is provided on the pattern by an inkjet method or a screen printing method, and the photocurable resin layer is subjected to a desired exposure to form the pattern. After the resist (etching mask material) is formed, the metal nanowires are immersed in an etchable etchant or the etchant is showered to form a conductive layer in a region not protected by the resist. A patterning method for breaking or disappearing metal nanowires.
In the case of the method (1) or (2), it is preferable to remove the resist on the conductive film by a conventional method after the patterning is completed, because a conductive laminate having excellent transparency can be obtained.

There is no restriction | limiting in particular in the method of providing the said etching mask material, For example, the apply | coating method, the printing method, the inkjet method etc. are mentioned.
The coating method is not particularly limited. For example, a roll coating method, a bar coating method, a dip coating method, a spin coating method, a casting method, a die coating method, a blade coating method, a bar coating method, a gravure coating method, a curtain coating method, Examples thereof include a spray coating method and a doctor coating method.
Examples of the printing method include letterpress (letterpress) printing, stencil (screen) printing, lithographic (offset) printing, and intaglio (gravure) printing.
The resist layer formed in this step may be a positive resist layer or a negative resist layer. In the case of a positive resist layer, the pattern-shaped exposed region is solubilized, and a patterned resist layer is formed in the unexposed region (unsolubilized region). In the case of a negative resist layer, the exposed region is A cured resist layer is formed, and by application of the solution, the unexposed portion, that is, the uncured portion of the resist layer is removed, and a patterned resist layer is formed.
According to this method, in the non-conductive area, both the metal nanowires and the binder contained in the conductive film are removed, and the substrate or the intermediate layer formed on the substrate is exposed.

There is no restriction | limiting in particular in the resist layer forming material used for the method of said (1), Any, such as a negative type, a positive type, a dry film type, can be used.
For the formation of the photoresist layer, commercially available alkali-soluble photoresists can be appropriately selected and used. For example, Fujifilm color mosaic series, FILS series, FIOS series, FMES series, FTENS series, FIES series, semiconductor process Each positive type, negative type photoresist series, Fuji Chemical Fuji Resist series can be used, and among them, FR series, FPPR series, FMR series, FDER series, etc. can be preferably used. Also, AZ Electronic Materials photoresist series can be used, among them, RFP series, TFP series, SZP series, HKT series, SFP, series, SR series, SOP series, SZC series, CTP series, ANR series, P4000. Series, TPM606, 40XT, nXT series and the like can be preferably used. Furthermore, each photoresist made by JSR can be widely used from a high resolution type to a low resolution type.
As dry film resists, Hitachi Chemical, photosensitive film for printed wiring boards, Asahi Kasei E-materials photosensitive dry film SUNFORT series, DuPont MRC dry film FXG series, FXR series, FX900 series, JSF100 series, SA100 series , LDI series, FRA series, CM series, FUJIFILM Transer series, etc., which can be used as appropriate.
What is necessary is just to select these resist layer forming materials suitably according to the resolution etc. of the pattern formed in a pattern transparent conductive film.
In the formation of the photoresist layer, when a dry film type resist layer forming material is used, a photosensitive resist layer of a dry film resist prepared in advance may be transferred to the surface of the formed conductive layer.

The exposure step in the method for forming the patterned transparent conductive film is preferably a step of performing exposure at an oxygen concentration of 5% or less using an etching mask material containing a photopolymerization initiator.
The exposure is preferably performed in an atmosphere having an oxygen concentration of 5% or less, more preferably 2% or less, still more preferably 1% or less, and 0.1% or less. It is particularly preferred.
When the exposure is performed in an atmosphere where the oxygen concentration exceeds 5%, by-products generated from the photopolymerization initiator contained in the etching mask material, or metal nanowires are disconnected by reaction with oxides such as ozone, Since the resistance value of the conductive part wiring after patterning is increased, it is not preferable. The disconnection of metal nanowires in an atmosphere having a high oxygen concentration tends to be particularly noticeable when metal nanowires having a small diameter are used.
Furthermore, it is not preferable to perform the exposure in an atmosphere in which the oxygen concentration exceeds 5% because the reaction efficiency in curing the etching mask material decreases and the tact time becomes longer.

The exposure is preferably performed in an inert gas atmosphere having an oxygen concentration of 5% or less.
The inert gas that can be used is not particularly limited as long as it does not interfere with the UV curing reaction when exposed using an ultraviolet irradiation device or an ultraviolet irradiation lamp. As the inert gas, nitrogen gas or argon gas is preferable, and nitrogen gas is more preferable because it is easily available and inexpensive.

As the exposure method, surface exposure (solid exposure) not using a photomask, surface exposure using a photomask, or scanning exposure using a laser beam may be performed. At this time, refractive exposure using a lens or reflection exposure using a reflecting mirror may be used, and exposure methods such as contact exposure, proximity exposure, reduced projection exposure, and reflection projection exposure can be used.
These exposure methods can be appropriately selected as necessary. For example, when the applied etching mask material is applied in a pattern in advance, solid exposure can be performed without using a photomask.
The light source used for the pattern exposure or exposure is selected in relation to the photosensitive wavelength range of the photoresist composition, but in general, ultraviolet rays such as g-line, h-line, i-line, and j-line are preferably used. Moreover, you may use ultraviolet LED.
The pattern exposure method is not particularly limited, and may be performed by surface exposure using a photomask, or may be performed by scanning exposure using a laser beam or the like. At this time, refractive exposure using a lens or reflection exposure using a reflecting mirror may be used, and exposure methods such as contact exposure, proximity exposure, reduced projection exposure, and reflection projection exposure can be used. The sample film surface temperature at the time of exposure is preferably low, preferably in the range of 0 ° C. to 80 ° C., more preferably 5 ° C. to 70 ° C., still more preferably 10 ° C. to 50 ° C. If the temperature at the time of exposure is lower than 0 ° C., it is difficult to control the temperature, and if it is 80 ° C. or higher, the number of disconnections of the metal nanowires increases and the resistance increase magnification increases.

The solution for dissolving the metal nanowire (referred to as an etching solution) can be appropriately selected according to the metal nanowire. For example, when the metal nanowire is a silver nanowire, in the so-called photographic science industry, bleaching fixer, strong acid, oxidizing agent, peroxidation mainly used for bleaching and fixing process of photographic paper of silver halide color photosensitive material Examples include hydrogen. Of these, bleach-fixing solution, dilute nitric acid, and hydrogen peroxide are particularly preferable. In addition, the dissolution of the silver nanowire by the solution for dissolving the silver nanowire may not completely dissolve the portion of the silver nanowire provided with the solution, and if the conductivity is lost, a part of the dissolution It may remain.
The concentration of the diluted nitric acid is preferably 1% by mass to 20% by mass.
The concentration of the hydrogen peroxide is preferably 3% by mass to 30% by mass.

As the bleach-fixing solution, for example, JP-A-2-207250, page 26, lower right column, line 1 to page 34, upper-right column, line 9 and JP-A-4-97355, page 5, upper left column, line 17 The processing materials and processing methods described in the 20th page, lower right column, line 20 can be preferably applied.
The bleach-fixing time is preferably 180 seconds or shorter, more preferably 120 seconds or shorter and 1 second or longer, and further preferably 90 seconds or shorter and 5 seconds or longer. Moreover, the water washing or stabilization time is preferably 180 seconds or shorter, more preferably 120 seconds or shorter and 1 second or longer.
The bleach-fixing solution is not particularly limited as long as it is a photographic bleach-fixing solution, and can be appropriately selected according to the purpose. For example, CP-48S, CP-49E (color paper bleaching) manufactured by FUJIFILM Corporation. Fixing agent), Kodak Ektacolor RA bleach-fixing solution, Dai Nippon Printing Co., Ltd. bleach-fixing solution D-J2P-02-P2, D-30P2R-01, D-22P2R-01, and the like. Among these, CP-48S and CP-49E are particularly preferable.

(Development process)
A development step for removing the patterned resist (etching mask material) used in the exposure step may be included.
The developing step is preferably a step of removing the etching mask material by applying a solvent. When a positive resist is used, it is preferably performed in a step after mask exposure and a step after etching, and when a negative resist is used, it is preferably performed in a step after etching.

As the solvent used in the development step, an alkaline solution is preferable.
The alkali contained in the alkaline solution is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include tetramethylammonium hydroxide, tetraethylammonium hydroxide, 2-hydroxyethyltrimethylammonium hydroxide, sodium carbonate, Examples thereof include sodium hydrogen carbonate, potassium carbonate, potassium hydrogen carbonate, sodium hydroxide, potassium hydroxide and the like.
Further, as the solvent, a commercially available developer for photoresist can be used.

There is no restriction | limiting in particular as the provision method of the said alkaline solution, According to the objective, it can select suitably, For example, application | coating, immersion, spraying etc. are mentioned. Among these, immersion is particularly preferable.
The immersion time of the alkaline solution is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 10 seconds to 5 minutes. The temperature of the alkaline solution can be appropriately selected according to the purpose, but is preferably 5 ° C to 50 ° C.

(Other processes)
The patterning step for forming the patterned transparent conductive film in the transparent conductive laminate of the present invention may further include other steps as necessary in addition to the exposure step and the development step.
Examples of other processes include washing with water after removing the etching mask, and a drying process.

Further, the conductive film may be formed on a target substrate by transfer using a transfer material.

Also, when the orientation of the metal nanowires is promoted in the coating process that is performed to form the conductive film, a polarizing conductive film tends to be formed. Examples of coating methods that maintain the randomness of the orientation of the nanowires include spray coating methods and inkjet coating methods. In addition, even when a coating method that promotes the orientation of nanowires (for example, a coating method such as a throttle die method) is employed, after coating along one direction, a direction different from the direction (for example, a direction orthogonal to the direction) ), The orientation of the nanowires can be relaxed.

Further, after the conductive film is formed, a treatment for reducing the orientation of the metal nanowires in the film may be performed. Metal nanowires in the conductive film formed by being applied along one direction tend to be oriented along the direction. Therefore, it is preferable to perform a stretching process (for example, a stretching process with a stretching ratio of 1% or more and less than 5%) along a direction (for example, a direction orthogonal to the direction) different from the direction of application because orientation is reduced. In addition, when implementing a extending | stretching process, after forming a electrically conductive film on flexible substrates, such as a polymer film, it is preferable to extend | stretch the electrically conductive film of the state supported by the board | substrate with a board | substrate.

The surface resistance of the conductive film is preferably 1 Ω / □ to 5,000 Ω / □, and more preferably 10 Ω / □ to 500 Ω / □.
The surface resistance can be measured by, for example, a surface resistance meter (Loresta-GP MCP-T600, manufactured by Mitsubishi Chemical Corporation).

The dry film thickness of the pattern transparent conductive film is preferably 0.005 to 2 μm, more preferably 0.01 to 1 μm.

Adhesive layer:
In this invention, it has the adhesion layer formed so that a pattern transparent conductive film may be covered. The adhesive layer is composed of an adhesive, and the adhesive strength of the adhesive layer is preferably 15 N / 25 mm or more (more preferably 30 to 50 N / 25 mm, particularly preferably 30 to 42 N / 25 mm).
In addition, it is preferable to use an adhesive whose water absorption rate of the adhesive layer is 2.0% or less (more preferably 1.0% or less, particularly preferably 0.9% or less). Although there is no specific lower limit of the water absorption rate, it is generally 0.5% or more. In the present specification, the pressure-sensitive adhesive used for the pressure-sensitive adhesive layer includes an adhesive in a broad sense. Also, depending on the material of the barrier film to which the adhesive layer adheres, the adhesive force of the adhesive layer may be different even in the same adhesive layer. However, in the present invention, the adhesive force of the adhesive layer is 15 N / 25 mm or more. There are no particular restrictions.

Examples of pressure-sensitive adhesives that can be used for the pressure-sensitive adhesive layer include acrylic pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives, silicone-based pressure-sensitive adhesives, urethane-based pressure-sensitive adhesives, and polyester-based pressure-sensitive adhesives. Acrylic adhesive is preferred.

The method for forming the adhesive layer is not particularly limited, and for example, the method described in JP2012-11637A can be used. Specifically, a coating method, a printing method, a bonding method, and the like can be mentioned. Among them, a method of installing by coating and a method of forming by sticking an adhesive sheet can be preferably used. The method of forming is more preferable.

As an environment for bonding the pressure-sensitive adhesive sheet, it is preferable to perform it in an environment where the dew point temperature is low. Bonding in a low dew point environment can reduce and prevent moisture uptake into the adhesive layer, and has an effect of suppressing an increase in resistance of the transparent conductive film. The dew point temperature is preferably −40 ° C. or lower, particularly preferably −60 ° C. or lower. After laminating the adhesive sheet, it is preferable to autoclave. The autoclave treatment has the effect of improving optical properties such as enhancing the adhesion between the adhesive layer and the barrier film and improving the transmittance and haze reduction of the transparent conductive laminate.
Furthermore, as a method for enhancing the adhesion between the adhesive layer and the barrier film, there is a method of treating the surface of the barrier film before the bonding. Specifically, the adhesion is improved by performing ultraviolet irradiation treatment, plasma treatment, and corona treatment on the barrier film surface.

The thickness of the adhesive layer is not particularly limited and may be appropriately selected depending on the intended purpose. For example, it is preferably 5 to 150 μm, more preferably 20 to 100 μm. By making the thickness of the adhesive layer 5 μm or more, it is possible to cover the steps and irregularities of the pattern transparent conductive film to be applied, and by making the thickness 150 μm or less, the transmittance of the adhesive layer can be sufficiently secured. Be

Other layers (functional layers):
The transparent conductive laminate of the present invention may have other layers (functional layers) in addition to the substrate, conductive film, adhesive layer, barrier film, and the like.
Examples of the functional layer include a protective film, an undercoat layer, an adhesion layer, a cushion layer, an overcoat protective layer, a protective film layer, an antifouling layer, a water repellent layer, an oil repellent layer, and a hard coat layer.
For example, an optical function can be imparted by laminating an antiglare layer, an antireflection layer, a low reflection layer, a λ / 4 layer, a polarizing layer, a retardation layer, and the like. These may be a single layer or a plurality of layers.

The transparent conductive laminate of the present invention is applied to a touch panel.

Touch panel:
The touch panel has a drive voltage of 1 V or more and is not particularly limited as long as it has the transparent conductive laminate of the present invention, and can be appropriately selected according to the purpose. For example, a surface capacitive touch panel, a projection type Examples include a capacitive touch panel and a resistive touch panel. The touch panel includes a so-called touch sensor and a touch pad.
The layer structure of the touch panel sensor electrode part in the touch panel is a bonding method in which two transparent electrodes are bonded, a method in which transparent electrodes are provided on both surfaces of a single substrate, a single-sided jumper or a through-hole method, or a single-area layer method. Either is preferable.
In addition, the projected capacitive touch panel is preferably AC driven rather than DC driven, and more preferably is a drive system that requires less time to apply voltage to the electrodes.

FIG. 2 is a schematic view of an example of a touch panel having the transparent conductive laminate of the present invention. The touch panel has a transparent conductive film on a surface opposite to the surface adjacent to the first barrier film of the transparent conductive laminate of the present invention and the first barrier film of the transparent conductive laminate. It has the laminated body laminated | stacked in order of the adhesion layer which covers an electrically conductive film, the 3rd barrier film | membrane, and a transparent film. In this aspect, you may abbreviate | omit the 1st barrier film of the transparent conductive laminated body of this invention as needed. In the embodiment shown in FIG. 2, even when a film substrate made of a polymer is used for the substrate and the transparent protective film (hereinafter also referred to as “cover film”), moisture from the outside does not enter the pattern transparent conductive film. It is possible to prevent the resistance of the pattern transparent conductive film from increasing and to prevent malfunction of the touch panel.

FIG. 3 is a schematic view of another example of a touch panel having the transparent conductive laminate of the present invention. A touch panel is an aspect which has a transparent film, a 3rd barrier film | membrane, a transparent conductive film, the adhesion layer which covers a transparent conductive film, and the transparent conductive laminated body of this invention. The third barrier film may be the same barrier film as the first and second barrier films, or may be a different barrier film. In the embodiment shown in FIG. 3, even if a film substrate made of a polymer is used as the substrate and the cover film, moisture from the outside does not enter the pattern transparent conductive film. Can be prevented from malfunctioning.

Water vapor permeability of the third barrier film shown in FIGS. 2 and 3 (more preferably, 0.05 g / (m ² · day) or less) preferably 0.1 g / (m ² · day) or less be The same film as the first barrier film and the second barrier film may be used, or different barrier films may be used.

The image display device used for the touch panel is not particularly limited, and a liquid crystal display device or an organic EL device usually used for a small electronic terminal can be used.

Examples of the present invention will be described below, but the present invention is not limited to these examples. In the examples, “%” and “parts” as the contents are based on mass. In this example, “part” indicating the blending amount indicates “part by mass” unless otherwise specified.

(Production of substrate having first barrier film)
<Production of substrate 1>
A substrate 1 was prepared by introducing an O ₂ gas onto a 125 μm thick PET film using a Si ₃ N ₄ target and forming a 150 nm thick SiON (silicon nitride oxide) barrier film by sputtering.

<Preparation of substrate 2>
A film 2-1 having a thickness of 1 μm was formed by applying an acrylic resin on a PET film having a thickness of 125 μm.
On the formed film 2-1, an Si ₂ N ₄ target was used to introduce O ₂ gas, and a 150 nm thick SiON film 2-2 was formed by sputtering.
A film 2-3 having a thickness of 1 μm is formed on the film 2-2 by applying an acrylic resin, and an O ₂ gas is introduced onto the film 2-3 using a Si ₃ N ₄ target. A barrier film composed of the films 2-1 to 2-4 was formed by forming a SiON film 4 having a thickness of 150 nm by sputtering, and the substrate 2 was manufactured.

<Preparation of substrate 3>
An O ₂ gas was introduced onto a PET film having a thickness of 125 μm using an Al target, and an alumina barrier film having a thickness of 100 nm was formed by sputtering to produce a substrate 3.

<Preparation of substrate 4>
A film 4-1 having a thickness of 1 μm was formed by applying an acrylic resin on a PET film having a thickness of 125 μm.
On the formed film 4-1, an O ₂ gas was introduced using an Al target, and an alumina film 4-2 having a thickness of 100 nm was formed by sputtering.
A film 4-3 having a film thickness of 1 μm is formed on the film 4-2 by applying an acrylic resin, and O ₂ gas is introduced onto the film 4-3 using an Al target, and a sputtering method is used. By forming an alumina film 4-4 with a film thickness of 100 nm, a barrier film composed of the films 4-1 to 4-4 was formed, and the substrate 4 was manufactured.
<Preparation of substrate 5>
A substrate 5 was produced by introducing an O ₂ gas onto a PET film having a thickness of 125 μm using a Si ₃ N ₄ target and forming a 100 nm thick SiON barrier film by sputtering.
<Preparation of substrate 6>
An O ₂ gas was introduced onto a PET film having a thickness of 125 μm using an Al target, and an alumina barrier film having a thickness of 150 nm was formed by sputtering to produce a substrate 6.

(Preparation of cover film having second barrier film)
<Preparation of cover film 1>
Using a Si ₃ N ₄ target, an O ₂ gas was introduced on a 125 μm thick polymethyl methacrylate resin (PMMA) film, and a 150 nm thick SiON (silicon nitride oxide) barrier film was formed by sputtering. Cover film 1 was produced.

<Preparation of cover film 2>
A 1 μm thick film 2′-1 was formed by applying an acrylic resin on a 125 μm thick polymethyl methacrylate resin (PMMA) film.
On the formed film 2′-1, an O ₂ gas was introduced using a Si ₃ N ₄ target, and a 150 nm-thick SiON film 2′-2 was formed by sputtering.
An acrylic resin is applied on the film 2′-2 to form a film 2′-3 having a thickness of 1 μm, and an O ₂ gas is introduced onto the film 3 using a Si ₃ N ₄ target. A cover film 2 was prepared by forming a SiON film 2′-4 having a film thickness of 150 nm by sputtering to form a barrier film composed of the films 2′-1 to 2′-4.

<Preparation of cover film 3>
A cover film 3 was prepared by introducing an O ₂ gas onto a 125 μm thick polymethyl methacrylate resin (PMMA) film using an Al target and forming a 100 nm thick alumina barrier film by sputtering.

<Preparation of cover film 4>
A cover film 4 is produced by introducing an O ₂ gas onto a 125 μm thick polymethyl methacrylate resin (PMMA) film using a Si ₃ N ₄ target and forming a 400 nm thick SiON barrier film by sputtering. did.

<Preparation of cover film 5>
A polymethyl methacrylate resin (PMMA) film having a thickness of 125 μm was used as the cover film 5.

<Preparation of cover film 6>
A film 6′-1 having a thickness of 1 μm was formed by applying an acrylic resin on a polymethyl methacrylate resin (PMMA) film having a thickness of 125 μm.
On the formed film 6′-1, an O ₂ gas was introduced using an Al target, and an alumina film 6′-2 having a thickness of 100 nm was formed by sputtering.
A film 6′-3 having a thickness of 1 μm is formed on the film 6′-2 by applying an acrylic resin, and an O ₂ gas is introduced onto the film 6′-3 using an Al target. A barrier film composed of films 6′-1 to 6′-4 was formed by forming an alumina film 6′-4 with a film thickness of 100 nm by sputtering, and a cover film 6 was produced.
<Preparation of cover film 7>
A cover film 7 is produced by introducing an O ₂ gas onto a 125 μm-thick polymethyl methacrylate resin (PMMA) film using a Si ₃ N ₄ target and forming a 100-nm thick SiON barrier film by sputtering. did.
<Preparation of cover film 8>
A cover film 3 was prepared by introducing an O ₂ gas onto a 125 μm-thick polymethyl methacrylate resin (PMMA) film using an Al target and forming an alumina barrier film having a thickness of 150 nm by sputtering.

(Measurement of water vapor permeability of barrier film)
Using a water vapor transmission rate measuring device (manufactured by MOCON, PERMATRAN-W3 / 31), the water vapor transmission rate of a substrate having a barrier film and a cover film having a barrier film was measured at 40 ° C. and a relative humidity of 90%. . Further, the results of measuring the water vapor transmission rate of a substrate not having a barrier film (that is, a PET film having a thickness of 125 μm) and a cover film not having a barrier film (that is, a polymethyl methacrylate resin (PMMA) film having a thickness of 125 μm). each ^{10.5g / (m 2 · day)} , was ^{12.4g / (m 2 · day)} . Both water vapor transmission rates exceeded 10 g / (m ² · day), and the water vapor transmission rate of the substrate itself and the cover film with the barrier film were measured because the water vapor transmission rate of the substrate itself was very large. The result obtained can be calculated as the water vapor permeability of the barrier film. Moreover, the value below 0.01 g / (m < ² > * day) which is the measurement limit of the said water-vapor-permeability measuring apparatus can be supplemented by measuring using the following method. First, metal Ca is vapor-deposited directly on the sample, and the film and the glass substrate are sealed with a commercially available sealing material for organic EL so that the vapor-deposited Ca is on the inside, thereby producing a sealed sample. Next, the water vapor transmission rate can be obtained by holding the sealed sample at the above temperature and humidity conditions and obtaining the optical density change of the metallic Ca (the metallic luster is reduced by hydroxylation or oxidation).

<Preparation of adhesive sheet A>
[Preparation of acrylic copolymer (1)]
Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, 95.5 parts of n-butyl acrylate, 0.5 parts of 2-hydroxyethyl acrylate, acrylic acid 4.0 parts and 0.2 part of 2,2′-azobisisobutylnitrile as a polymerization initiator are dissolved in 100 parts of ethyl acetate, and after substitution with nitrogen, polymerization is carried out at 80 ° C. for 8 hours to obtain a weight average molecular weight of 800,000. An acrylic copolymer (1) was obtained.

[Preparation of acrylic copolymer (2)]
Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, 95.0 parts of methyl methacrylate, 5.0 parts of dimethylaminoethyl methacrylate and 2 as a polymerization initiator , 2′-azobisisobutylnitrile (1.0 part) was dissolved in ethyl acetate (100 parts), purged with nitrogen, and polymerized at 80 ° C. for 8 hours to obtain a methacrylic copolymer (2) having a weight average molecular weight of 20,000. .

“Preparation of adhesive A”
20 parts of the acrylic copolymer (2) was added to 100 parts of the acrylic copolymer (1) and diluted with ethyl acetate to obtain a pressure-sensitive adhesive A having a resin solid content of 30%.

Polyester having a thickness of 50 μm obtained by adding 0.7 part of an isocyanate-based cross-linking agent (Coronate L-45 manufactured by Nippon Polyurethane Co., Ltd., solid content: 45%) to 100 parts of the pressure-sensitive adhesive A, stirring for 15 minutes, and then removing one side with a silicone compound. The film (# 50 release film) was coated so that the thickness after drying was 25 μm, and dried at 75 ° C. for 5 minutes. The obtained pressure-sensitive adhesive sheet and a 38 μm-thick polyester film (# 38 release film) having one surface peel-treated with a silicone compound were bonded together. Thereafter, it was aged at 23 ° C. for 5 days to obtain a support-less pressure-sensitive adhesive sheet A having a thickness of 25 μm.

<Preparation of adhesive sheet B>
[Preparation of acrylic copolymer (3)]
Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, 91.5 parts of n-butyl acrylate, 0.5 part of 2-hydroxyethyl acrylate, acrylic acid 8.0 parts and 0.2 part of 2,2′-azobisisobutylnitrile as a polymerization initiator are dissolved in 100 parts of ethyl acetate, and after substitution with nitrogen, polymerization is carried out at 80 ° C. for 8 hours to give a weight average molecular weight of 800,000. An acrylic copolymer (3) was obtained.

“Preparation of adhesive B”
10 parts of the acrylic copolymer (2) was added to 100 parts of the acrylic copolymer (3), and diluted with ethyl acetate to obtain an adhesive B having a resin solid content of 30%.

Polyester having a thickness of 50 μm obtained by adding 0.7 part of an isocyanate-based crosslinking agent (Coronate L-45 manufactured by Nippon Polyurethane Co., Ltd., solid content: 45%) to 100 parts of the above-mentioned adhesive B, stirring for 15 minutes, and then removing one side with a silicone compound. The film (# 50 release film) was coated so that the thickness after drying was 25 μm, and dried at 75 ° C. for 5 minutes. The obtained pressure-sensitive adhesive sheet and a 38 μm-thick polyester film (# 38 release film) having one surface peel-treated with a silicone compound were bonded together. Thereafter, it was aged at 23 ° C. for 5 days to obtain a support-less pressure-sensitive adhesive sheet B having a thickness of 25 μm.

<Preparation of adhesive sheet C>
“Preparation of adhesive C”
10 parts of the acrylic copolymer (3) was added to 100 parts of the acrylic copolymer (2), and diluted with ethyl acetate to obtain an adhesive C having a resin solid content of 30%.

Polyester having a thickness of 50 μm obtained by adding 0.7 part of an isocyanate-based crosslinking agent (Coronate L-45 manufactured by Nippon Polyurethane Co., Ltd., solid content: 45%) to 100 parts of the above-mentioned pressure-sensitive adhesive, stirring for 15 minutes, and then removing one side with a silicone compound. The film (# 50 release film) was coated so that the thickness after drying was 25 μm, and dried at 75 ° C. for 5 minutes. The obtained pressure-sensitive adhesive sheet and a 38 μm-thick polyester film (# 38 release film) having one surface peel-treated with a silicone compound were bonded together. Thereafter, it was aged at 23 ° C. for 5 days to obtain a support-less pressure-sensitive adhesive sheet C having a thickness of 25 μm.

(Measurement of water absorption of adhesive layer)
The pressure-sensitive adhesive sheet prepared above is cut out to a size of 100 mm × 100 mm, left under conditions of 60 ° C. and 90% RH for 100 hours, immediately peeled off the release film on one side of the pressure-sensitive adhesive sheet, and bonded to a 150 mm × 150 mm aluminum foil. And weigh (this mass is referred to as W1). The other release film of the pressure-sensitive adhesive sheet is peeled off, dried for 2 hours at 105 ° C., and then weighed (this mass is designated as W2). The water absorption rate of the adhesive layer of the adhesive sheet was calculated by the following formula.
Water absorption of adhesive layer (%) = (W1-W2) / W2 × 100

(Measurement of adhesive strength of adhesive layer)
The adhesion strength between the barrier film and the adhesive layer was evaluated by the following method.
The release film on one side of the pressure-sensitive adhesive sheet prepared above is peeled off, bonded to a polyethylene terephthalate film (thickness: 25 μm), cut to a width of 25 mm and a length of 100 mm, and then the release film on the other side is peeled off. A cover film having a barrier film was attached. At this time, the bonding is performed so that the barrier film faces the adhesive sheet. After pasting on the cover film having the barrier film, the autoclave treatment was performed for 20 minutes under the condition of 45 ° C./0.5 MPa. Thirty minutes after the autoclave treatment, 180 ° peel adhesion was measured. The measurement conditions for 180 ° peel adhesive strength are peeling angle: 180 °, tensile speed: 300 mm / min, temperature: 23 ° C., humidity: 50% RH, and a film made of polyethylene terephthalate from a cover film having a barrier film. By peeling the pressure-sensitive adhesive sheet bonded to the film, 180 ° peel adhesive strength was measured, and the adhesion strength between the barrier film and the pressure-sensitive adhesive layer was evaluated.

(Preparation of aqueous dispersion of silver nanowires)
-Preparation of silver nanowire dispersion (1)-
A silver nitrate solution 101 was prepared by dissolving 60 g of silver nitrate powder in 370 g of propylene glycol. 72.0 g of polyvinylpyrrolidone (molecular weight 55,000) was added to 4.45 kg of propylene glycol, and the temperature was raised to 90 ° C. while venting nitrogen gas through the gas phase portion of the container. This solution was designated as reaction solution 101. While maintaining the aeration of nitrogen gas, 3.00 g of the silver nitrate solution 101 was added to the reaction solution 101 that was vigorously stirred, and the mixture was heated and stirred for 1 minute. Further, a solution in which 11.8 g of tetrabutylammonium chloride was dissolved in 100 g of propylene glycol was added to this solution to obtain a reaction solution 102.

200 g of the silver nitrate solution 101 was added to the reaction solution 102 which was kept at 90 ° C. and stirred at a stirring speed of 500 rpm at an addition speed of 50 ml / min. The stirring speed was reduced to 100 rpm, the aeration of nitrogen gas was stopped, and heating and stirring were performed for 15 hours. 220 g of the silver nitrate solution 101 was added to this liquid which was kept at 90 ° C. and stirred at a stirring speed of 100 rpm at an addition speed of 0.5 ml / min, and stirring was continued for 2 hours after the addition was completed. The stirring was changed to 500 rpm, and after adding 1.0 kg of distilled water, the mixture was cooled to 25 ° C. to prepare a charged solution 101.

Using an ultrafiltration module with a molecular weight cut off of 150,000, ultrafiltration was performed as follows. Addition and concentration of a mixed solution of distilled water and 1-propanol (volume ratio of 1: 1) to the charged solution 101 and concentration were repeated until the filtrate finally had a conductivity of 50 μS / cm or less. The obtained filtrate was concentrated to obtain a silver nanowire dispersion liquid (1) having a metal content of 0.45%.

About the silver nanowire of the obtained silver nanowire dispersion liquid (1), the average minor axis length and the average major axis length were measured as described above.
As a result, the average minor axis length was 32.5 nm and the average major axis length was 15.6 μm. Hereinafter, when it describes with "silver nanowire dispersion liquid (1)", the silver nanowire dispersion liquid obtained by the said method is shown.

-Preparation of silver nanowire dispersion (2)-
In the preparation of the silver nanowire dispersion liquid (1), a silver nanowire having a metal content of 0.45% was prepared in the same manner as the preparation of the silver nanowire dispersion liquid (1) except that 4.50 g of the silver nitrate solution 101 was used. A dispersion (2) was obtained. About the silver nanowire of the obtained silver nanowire dispersion liquid (2), the average minor axis length and the average major axis length were measured as described above. As a result, the average minor axis length was 70.6 nm, and the average major axis length was 9.2 μm. Hereinafter, when it describes with "silver nanowire dispersion liquid (2)", the silver nanowire dispersion liquid obtained by the said method is shown.

-Preparation of silver nanowire dispersion (3)-
In the preparation of the silver nanowire dispersion liquid (1), a silver nanowire having a metal content of 0.45% was prepared in the same manner as the preparation of the silver nanowire dispersion liquid (1) except that 5.00 g of the silver nitrate solution 101 was used. A dispersion (3) was obtained. About the silver nanowire of the obtained silver nanowire dispersion liquid (3), the average minor axis length and the average major axis length were measured as described above. As a result, the average minor axis length was 45.9 nm and the average major axis length was 12.4 μm. Henceforth, when it describes with "silver nanowire dispersion liquid (3)", the silver nanowire dispersion liquid obtained by the said method is shown.

-Preparation of silver nanowire dispersion (4)-
In the preparation of the silver nanowire dispersion liquid (1), a silver nanowire having a metal content of 0.45% was prepared in the same manner as the preparation of the silver nanowire dispersion liquid (1) except that 6.50 g of the silver nitrate solution 101 was used. A dispersion (4) was obtained. About the silver nanowire of the obtained silver nanowire dispersion liquid (4), the average minor axis length and the average major axis length were measured as described above. As a result, the average minor axis length was 112.8 nm and the average major axis length was 7.8 μm. Henceforth, when it describes with "silver nanowire dispersion liquid (4)", the silver nanowire dispersion liquid obtained by the said method is shown.

-Preparation of silver nanowire dispersion (5)-
The following additive solutions A, B, C, and D were prepared in advance.
[Additive liquid A]
Stearyltrimethylammonium chloride 55 mg, stearyltrimethylammonium hydroxide 10% aqueous solution 5.5 g, and glucose 1.8 g were dissolved in distilled water 115.0 g to obtain reaction solution A-1. Further, 65 mg of silver nitrate powder was dissolved in 1.8 g of distilled water to obtain an aqueous silver nitrate solution A-1. The reaction solution A-1 was kept at 25 ° C., and the aqueous silver nitrate solution A-1 was added with vigorous stirring. After the addition of the aqueous silver nitrate solution A-1, the mixture was vigorously stirred for 180 minutes to obtain additive solution A.
[Additive solution B]
42.0 g of silver nitrate powder was dissolved in 958 g of distilled water.
[Additive liquid C]
75 g of 25% aqueous ammonia was mixed with 925 g of distilled water.
[Additive liquid D]
400 g of polyvinylpyrrolidone (K30) was dissolved in 1.6 kg of distilled water.
Next, a silver nanowire dispersion liquid (5) was prepared as follows. 1.30 g of stearyltrimethylammonium bromide powder, 33.1 g of sodium bromide powder, 1,000 g of glucose powder and 115.0 g of nitric acid (1N) were dissolved in 12.7 kg of distilled water at 80 ° C. While this liquid was kept at 80 ° C. and stirred at 500 rpm, the additive liquid A was added successively at an addition rate of 250 ml / min, the additive liquid B at 500 ml / min, and the additive liquid C at 500 ml / min. The stirring speed was 200 rpm and heating was performed at 80 ° C. Subsequently, after the stirring speed was set to 200 rpm, the heating and stirring was continued for 100 minutes, and then the mixture was cooled to 25 ° C. Thereafter, the stirring speed was changed to 500 rpm, and the additive solution D was added at 500 ml / min. This solution was used as the charged solution 101. Next, 1-propanol was vigorously stirred, and the charged solution 101 was added to the mixture so that the mixing ratio was 1: 1. The obtained mixed solution was stirred for 3 minutes to obtain a charged solution 102.

Using an ultrafiltration module with a molecular weight cut off of 150,000, ultrafiltration was performed as follows. After the feed solution 102 is concentrated four times, addition and concentration of a mixed solution of distilled water and 1-propanol (volume ratio of 1: 1) to the feed solution 102 is finally performed, and finally the conductivity of the filtrate is 50 μS / cm. Repeat until: The obtained filtrate was concentrated to obtain a silver nanowire dispersion liquid (5) having a metal content of 0.45%.

About the silver nanowire of the obtained silver nanowire dispersion liquid (5), the average minor axis length and the average major axis length were measured as described above.
As a result, the average minor axis length was 17.2 nm and the average major axis length was 8.8 μm.

(Preparation of transparent conductive laminate 1: Example 1)
<Preparation of pattern transparent conductive film 1>
The solution of the alkoxide compound having the following composition was stirred at 60 ° C. for 1 hour to confirm that the solution became uniform. When the weight average molecular weight (Mw) of the obtained alkoxide compound solution (sol-gel solution) was measured by GPC (polystyrene conversion), Mw was 4,400. 2.24 parts of the sol-gel liquid and 17.76 parts of the aqueous silver nanowire dispersion (1) obtained in Preparation Example 1 were mixed, and further diluted with distilled water and 1-propanol to obtain a sol-gel coating liquid. The solvent ratio of the obtained sol-gel coating solution was distilled water: 1-propanol = 60: 40. Amount of silver 0.015 g / m ² by a bar coating method on the surface of the barrier film side of the substrate 1, after the total solid content in the coating solution was applied to the gel coating solution so that 0.120 g / m ^2, 120 The sol-gel reaction was caused to dry at 1 degreeC for 1 minute, and the transparent conductive film 1 which consists of silver nanowire was formed.
<Solution of alkoxide compound>
・ Tetraethoxysilane 5.0 parts (KBE-04, manufactured by Shin-Etsu Chemical Co., Ltd.)
・ 1% acetic acid aqueous solution 11.0 parts ・ Distilled water 4.0 parts

According to the method described in paragraphs [0371] to [0372] of JP-T-2010-507199, the transparent conductive film 1 can be patterned using a conventional photolithography etching technique.
A photoresist (TMSMR-8900LB: manufactured by Tokyo Ohka Kogyo Co., Ltd.) is applied to the transparent conductive film 1, and after pattern exposure using a mask, development is performed with a developer (NMD-W: Tokyo Ohka Kogyo Co., Ltd.). After forming a patterned photoresist, the silver nanowires were etched with a silver etching solution (SEA-2: manufactured by Kanto Chemical Co., Inc.). Thereafter, the photoresist was stripped using a neutral stripping solution (PK-SFR8120: manufactured by Parker Corporation), and the pattern transparent conductive film 1 was prepared. In addition, as shown in FIG. 4, the space width of the conductive area of the element of the environmental resistance test and the flexibility evaluation was 50 μm. For haze evaluation, a conductive area was patterned to a size of 5 cm × 5 cm.

Thereafter, an extraction electrode in which an extraction electrode of Mo (40 nm) / Al (100 nm) / Mo (40 nm) was produced by sputtering was formed on the patterned transparent conductive film 1. The extraction electrode was patterned by using a shadow metal mask during sputtering film formation.

The surface on the barrier film side of the cover film 1 and the pattern transparent conductive film 1 were bonded together using an adhesive sheet A. The bonding was performed in a glove box having a dew point temperature of −60 ° C. After bonding, the transparent conductive laminate 1 was produced by subjecting the autoclave treatment to a condition of 45 ° C./0.5 MPa for 20 minutes.

(Preparation of transparent conductive laminates 2 to 21)
In the production of the transparent conductive laminate 1, the transparent conductive laminate 2 was prepared in the same manner as the production of the transparent conductive laminate 1, except that the aqueous dispersion of the substrate, the cover film, and the silver nanowire was changed as shown in the following table. To 21 were produced.
Moreover, in the transparent conductive laminates 14, 17, 18, 19 and 20, before bonding, the surface of the barrier film of the cover film is irradiated with ultraviolet rays to be washed to enhance the adhesion between the barrier film and the adhesive layer. It was.

(Evaluation)
<Environmental resistance test>
Under an environmental condition of 60 ° C. and 90% RH, a voltage of 10 V DC was continuously applied for 120 hours (5 days) between the AB electrodes in FIG. 4, and then the resistance change of the + electrode was measured. evaluated.
The resistance was measured using a microprober (MP-10A, manufactured by Nihon Micronics) and an analyzer (4155C, manufactured by Agilent).
The resistance change is expressed by the following equation.
Resistance change = (240 hours later + electrode resistance) / (before test + electrode resistance)

AA: resistance change is less than 1.1, excellent level A: resistance change is 1.1 or more and less than 1.5, good level B: resistance change is 1.5 or more and less than 2.0, no problem level C: Resistance change is 2.0 or more, problematic level

<Haze>
The haze value of the conductive area was measured using a haze guard plus manufactured by Gardner. The measurement was performed at the center of a 5 cm × 5 cm sample.

A: haze value is less than 1.5%, good level B: haze value is 1.5% or more and less than 2.5%, no problem level C: haze value is 2.5% or more, problematic level

<Flexibility (flexibility)>
Using a cylindrical mandrel bending tester (manufactured by Cortec Co., Ltd.) equipped with a cylindrical mandrel with a diameter of 20 mm, the transparent conductive laminate is subjected to a bending test 10 times, and then the above environmental resistance test (ion migration test) is performed. The resistance change of the + electrode before and after the test was measured.
The resistance was measured using a microprober (MP-10A, manufactured by Nihon Micronics) and an analyzer (4155C, manufactured by Agilent).
The resistance change is expressed by the following equation.
Resistance change = (240 hours later + electrode resistance) / (before test + electrode resistance)

A: resistance change less than 1.5, good level B: resistance change from 1.5 to less than 2.0, no problem level C: resistance change of 2.0 or more, problematic level

From the table | surface, the water vapor permeability | transmittance of a 1st and 2nd barrier film | membrane is 0.1 g / (m < ² > * day) or less respectively, The pattern transparent conductive film containing metal nanowire whose average short axis length is 50 nm or less It can be seen that the transparent conductive laminate in which is sealed with the first and second barrier films has good haze and excellent environmental resistance test. On the other hand, it can be seen that the comparative example which is not sealed with a barrier film having a water vapor transmission rate of 0.1 g / (m ² · day) or less is inferior in the environmental resistance test as compared with the examples.

From Comparative Examples 4 to 5, the transparent conductive laminate using metal nanowires having an average minor axis length of more than 50 nm is resistant even if a barrier film having a water vapor permeability of more than 0.1 g / (m ² · day) is used. Although it is excellent in environmental tests, it can be seen that the haze is large and the visibility is poor. In a transparent conductive laminate using silver nanowires with an average minor axis length of 50 nm or less that has a small haze and is excellent in appearance, both sides of the patterned transparent conductive film have a water vapor transmission rate of 0.1 g / (m ² · day) or less. By sealing with a barrier film, the environment resistance test characteristics can be improved, and both visibility and environment resistance test characteristics can be achieved.
From Examples 1 to 11, by setting the adhesive force between the barrier film and the adhesive layer to 30 N / 25 mm or more and the water absorption rate of the adhesive layer to 1% or less, the environmental resistance test characteristics were further improved, and the adhesive force was 50 N / It can be seen that by setting the thickness of 25 mm or less and the thickness of the barrier film to 300 nm or less, it is possible to provide a transparent conductive laminate having further excellent flexibility.

(Production of touch panel: Example 12)
The touch panel of the aspect of FIG. 3 was produced by bonding the transparent conductive film and the board | substrate 1 to the board | substrate of the transparent conductive laminated body of Example 1 using the adhesive sheet A. FIG.

(Production of touch panel: Example 13)
The touch panel of the aspect of FIG. 2 was produced by bonding the transparent conductive film, the pressure-sensitive adhesive sheet A, and the substrate 1 to the substrate of the transparent conductive laminate of Example 1.

(Production of touch panel: Comparative Example 11)
As shown in FIG. 6, a touch panel was produced using a substrate without a barrier film and a cover film.

The touch panels of Examples 12 and 13 and Comparative Example 11 were driven at 5 V for 240 hours under an environmental condition of 85 ° C. and 90% RH.

The touch panels of Examples 12 and 13 were driven without problems after 240 hours, but the touch panel of Comparative Example 11 was not driven.

DESCRIPTION OF SYMBOLS 1 1st barrier film 2 Pattern transparent conductive film 3, 8 Adhesive layer 4 2nd barrier film 5, 10 Transparent film 6 Transparent protective film 7 3rd barrier film 9 Transparent conductive film 11 Extraction electrode

Claims

A patterned transparent conductive film containing metal nanowires having an average minor axis length of 5 to 50 nm formed on the surface of the first barrier film directly or via another layer; and the pattern transparent An adhesive layer covering the conductive film, and a second barrier film adjacent to the adhesive layer,
The transparent conductive laminate, wherein the water vapor permeability of each of the first and second barrier films is 0.1 g / (m 2 · day) or less.
The first barrier film has a transparent film made of a resin on the surface opposite to the surface on which the patterned transparent conductive film is formed, and is opposite to the surface adjacent to the adhesive layer of the second barrier film. The transparent conductive laminate according to claim 1, comprising a transparent protective film made of a resin on the surface.
The transparent conductive laminate according to claim 1 or 2, wherein the metal nanowire has an average minor axis length of 5 to 25 nm.
The transparent conductive laminate according to any one of claims 1 to 3, wherein the adhesive strength of the adhesive layer is 15 N / 25 mm or more.
The transparent conductive laminate according to any one of claims 1 to 4, wherein the adhesive strength of the adhesive layer is 30 to 50 N / 25 mm.
The transparent conductive laminate according to any one of claims 1 to 5, wherein the water absorption of the adhesive layer is 1.0% or less.
The transparent conductive laminate according to any one of claims 1 to 6, wherein the metal nanowire contains silver.
The transparent conductive laminate according to any one of claims 1 to 7, wherein the first and second barrier films are SiON, and the film thicknesses of the first and second barrier films are each 300 nm or less. body.
A touch panel comprising the transparent conductive laminate according to any one of claims 1 to 8.
The touch panel according to claim 9, wherein the drive voltage is 1 V or more.