JP2010244746A - Transparent electrode, method for manufacturing transparent electrode and organic electroluminescent element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transparent electrode endowed with high conductivity and transparency as well as superb smoothness even after environmental test under high-temperature and high-humidity environments, and excellent in stability (all light transmittance, surface resistance, and surface roughness (Ra, Ry)), a method for manufacturing the transparent electrode, and an organic electroluminescent element excellent in emission uniformity using the transparent electrode. <P>SOLUTION: The transparent electrode includes a conductive fiber, conductive polymer, and binder resin for being uniformly dispersed in an aqueous system solvent on a transparent base material. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a transparent electrode, a method for producing the transparent electrode, and an organic electroluminescent element having the transparent electrode, and various kinds of liquid crystal display elements, organic light emitting elements, inorganic electroluminescent elements, solar cells, electromagnetic wave shields, electronic paper, touch panels, and the like. The present invention relates to a transparent electrode, a method for producing the transparent electrode, and an organic electroluminescence element (hereinafter also referred to as an organic EL element) having the transparent electrode, which can be suitably used in the field.

  In recent years, various types of display technologies such as liquid crystal, plasma, organic electroluminescence, and field emission have been developed in response to the increasing demand for thin TVs. In any of these displays with different display methods, the transparent electrode is an essential constituent technology. In addition to televisions, transparent electrodes are an indispensable technical element in touch panels, mobile phones, electronic paper, various solar cells, and various electroluminescence light control elements.

  Conventionally, an ITO transparent electrode in which a composite oxide (ITO) film of indium-tin is formed on a transparent substrate such as glass or a transparent plastic film by a vacuum deposition method or a sputtering method has been mainly used. It was. However, indium used in ITO is a rare metal and removal of indium is desired due to the rising price. In addition, roll-to-roll using a flexible substrate has been desired along with an increase in display screen and productivity.

  A technique using a conductive fiber is disclosed, and a part of the conductive fiber is fixed to a flexible substrate with a transparent resin film, and a part of the conductive fiber is projected on the surface of the transparent resin film to form an electrode. Has been proposed (see, for example, Patent Document 1). However, since the electrode having such a structure has conductivity only at the portion where the conductive fiber protrudes on the surface, the conductive fiber protrudes on the surface, and for the technical application in which the smoothness of the electrode surface is required. It had the problem that it was not applicable.

  Also, a transparent electrode has been proposed in which polyurethane is overcoated on silver nanowires coated on a transparent substrate and the electrode surface is smooth (see, for example, Patent Document 2). However, when a coating type organic EL element is laminated on the transparent electrode, the surface light emission and the light emission life are poor, and there is a problem of improving the surface uniformity.

  It is disclosed that the average roughness (Ra) of the surface of the ITO transparent electrode is 2 nm or less (see, for example, Patent Document 3). Moreover, it is proposed that the average surface roughness (Ra) of the ITO transparent conductive film surface used for an organic electroluminescent element is 1.2 nm or less (for example, refer patent document 4). When an organic electroluminescence element is manufactured using an electrode having protrusions on the surface of the transparent electrode as in Patent Documents 1 to 3, there is a problem that the protrusions are short-circuited from the starting point, such as a short circuit between the anode and the cathode. Further, there is a problem that a transparent resin exists between the protrusions and a function as a surface electrode cannot be obtained.

  In addition, as a transparent electrode excellent in productivity, a method of forming a transparent electrode by coating or printing using a coating solution obtained by dissolving or dispersing a conductive polymer material typified by a π-conjugated polymer in an appropriate solvent Has also been proposed (see, for example, Patent Document 5). However, compared with metal oxide transparent electrodes such as ITO by vacuum film-forming method, it has low conductivity and inferior in transparency, and has the problem of achieving both high conductivity and high transmittance / transparency. It was.

JP 2006-519712 A US Patent Application Publication No. 2007/0074316 JP-A-2005-050730 JP 2003-335552 A JP-A-6-273964

  The present invention has been made in view of the above problems, and an object of the present invention is to have high conductivity and transparency even after an environmental test under a high temperature and high humidity environment, and to have good smoothness and stability. Provided are a transparent electrode having excellent total light transmittance, surface resistance, and surface roughness (Ra, Ry), a method for producing the transparent electrode, and an organic electroluminescence device having excellent light emission uniformity using the transparent electrode. There is to do.

  The above object of the present invention can be achieved by the following constitution.

1. In a transparent electrode having a transparent conductive layer having a conductive fiber, a conductive polymer, and a binder resin on a transparent substrate,
A transparent electrode, wherein the binder resin is a binder resin that can be uniformly dispersed in an aqueous solvent.

  2. 2. The transparent electrode according to 1, wherein the conductive fiber, the conductive polymer, and a binder resin that can be uniformly dispersed in an aqueous solvent are contained in a transparent conductive layer on a transparent substrate.

  3. A second transparent conductive material on the first transparent conductive layer containing the conductive fiber in a first transparent conductive layer on a transparent substrate and a binder resin that can be uniformly dispersed in the conductive polymer and an aqueous solvent. 2. The transparent electrode as described in 1 above, which is contained in a layer.

  4). 4. The transparent electrode according to any one of 1 to 3, wherein the conductive fiber is a silver nanowire.

  5. 5. The transparent electrode according to any one of 1 to 4, wherein the binder resin that can be uniformly dispersed in the aqueous solvent is at least one selected from an acrylic resin and a urethane resin.

6). In the method for producing a transparent electrode having a transparent conductive layer having a conductive fiber, a conductive polymer, and a binder resin on a transparent substrate,
A method for producing a transparent electrode, wherein the binder resin is a binder resin that can be uniformly dispersed in an aqueous solvent.

  7). A transparent conductive layer is formed by applying an aqueous dispersion containing a conductive resin, a conductive polymer, and a binder resin that can be uniformly dispersed in an aqueous solvent on a transparent substrate. 6. The method for producing a transparent electrode according to 6.

8). Applying a first transparent conductive layer containing the conductive fibers on a transparent substrate;
Forming a second transparent conductive layer by applying an aqueous dispersion containing a binder resin that can be uniformly dispersed in the conductive polymer and an aqueous solvent on the first transparent conductive layer;
The method for producing a transparent electrode as described in 6 above, wherein:

  9. The method for producing a transparent electrode according to any one of 6 to 8, wherein the conductive fiber is a silver nanowire.

  10. 10. The method for producing a transparent electrode according to any one of 6 to 9, wherein the binder resin that can be uniformly dispersed in the aqueous solvent is at least one selected from an acrylic resin and a urethane resin. .

  11. 6. An organic electroluminescence device comprising the transparent electrode according to any one of 1 to 5 above.

  According to the present invention, it has high conductivity and transparency even after an environmental test under a high temperature and high humidity environment, and has good smoothness, stability (total light transmittance, surface resistance, surface roughness (Ra , Ry)), a transparent electrode, a method for producing the transparent electrode, and an organic electroluminescence device having excellent light emission uniformity using the transparent electrode.

It is a structure schematic diagram of the transparent electrode of this invention.

  Hereinafter, although the form for implementing this invention is demonstrated, this invention is not limited to these.

  The present invention provides a transparent electrode having a transparent conductive layer having conductive fibers, a conductive polymer, and a binder resin on a transparent substrate, and the binder resin is a binder resin that can be uniformly dispersed in an aqueous solvent. It is characterized by.

  In the present invention, in particular, by including a binder resin that can be uniformly dispersed in an aqueous solvent in a transparent electrode, it has high conductivity and transparency even after an environmental test under a high temperature and high humidity environment, and has a good smoothness. And an organic electroluminescence device having excellent stability (total light transmittance, surface resistance, surface roughness (Ra, Ry)) and excellent light emission uniformity using the transparent electrode. .

  The present invention will be described in more detail.

(Transparent substrate)
In the present invention, “transparent” means in the visible light wavelength region measured by a method in accordance with “Testing method of total light transmittance of plastic-transparent material” of JIS K 7361-1 (corresponding to ISO 13468-1). It means that the total light transmittance is 60% or more.

  The transparent substrate used for the transparent electrode of the present invention is not particularly limited as long as it has high light transmittance. For example, a substrate such as a glass substrate, a resin substrate, or a resin film is preferably used in terms of excellent hardness as a substrate and easy formation of a conductive layer on the surface. It is preferable to use a transparent resin film from the viewpoint of flexibility.

  There is no restriction | limiting in particular in the transparent resin film which can be preferably used as a transparent base material by this invention, About the material, a shape, a structure, thickness, etc., it can select suitably from well-known things. For example, polyester resin films such as polyethylene terephthalate (PET), polyethylene naphthalate, modified polyester, polyethylene (PE) resin films, polypropylene (PP) resin films, polystyrene resin films, polyolefin resin films such as cyclic olefin resins, Vinyl resin films such as polyvinyl chloride and polyvinylidene chloride, polyether ether ketone (PEEK) resin film, polysulfone (PSF) resin film, polyether sulfone (PES) resin film, polycarbonate (PC) resin film, polyamide resin A film, a polyimide resin film, an acrylic resin film, a triacetyl cellulose (TAC) resin film, and the like can be given. If the resin film transmittance of 80% or more in nm), can be preferably applied to a transparent resin film of a transparent substrate according to the present invention. Among these, from the viewpoint of transparency, heat resistance, ease of handling, strength and cost, it is preferably a biaxially stretched polyethylene terephthalate film, a biaxially stretched polyethylene naphthalate film, a polyethersulfone film, or a polycarbonate film, and biaxially stretched. More preferred are polyethylene terephthalate films and biaxially stretched polyethylene naphthalate films.

  The transparent substrate used in the present invention can be subjected to a surface treatment or an easy-adhesion layer in order to ensure the wettability and adhesion of the coating solution. A conventionally well-known technique can be used about a surface treatment or an easily bonding layer. For example, the surface treatment includes surface activation treatment such as corona discharge treatment, flame treatment, ultraviolet treatment, high frequency treatment, glow discharge treatment, active plasma treatment, and laser treatment. Examples of the easy adhesion layer include polyester, polyamide, polyurethane, vinyl copolymer, butadiene copolymer, acrylic copolymer, vinylidene copolymer, and epoxy copolymer. When the transparent resin film is a biaxially stretched polyethylene terephthalate film, by making the refractive index of the easy adhesion layer adjacent to the film 1.57-1.63, the interface reflection between the film substrate and the easy adhesion layer can be achieved. Since it can reduce and can improve the transmittance | permeability, it is more preferable. The method for adjusting the refractive index can be carried out by appropriately adjusting the ratio of the oxide sol having a relatively high refractive index such as tin oxide sol or cerium oxide sol and the binder resin. The easy adhesion layer may be a single layer, but may be composed of two or more layers in order to improve adhesion. Moreover, the barrier coat layer may be formed in advance on the transparent substrate, or the hard coat layer may be formed in advance on the opposite side to which the transparent conductive layer is transferred.

[Transparent electrode]
A structural schematic diagram of the transparent electrode of the present invention is shown in FIG. FIG. 1 is a structural schematic diagram of a representative transparent electrode of the present invention, which has a transparent conductive layer 31 on a transparent substrate 51, and the transparent conductive layer includes a conductive fiber 11 and a conductive material 21. Composed. In the present invention, other configurations are not particularly limited.

  The transparent substrate can be subjected to surface treatment as described above, and various functional layers can be provided depending on the purpose.

In the transparent electrode of the present invention, the total light transmittance is preferably 60% or more, more preferably 70% or more, and particularly preferably 80% or more. The total light transmittance can be measured according to a known method using a spectrophotometer or the like. Moreover, as an electrical resistance value of the transparent conductive layer in the transparent electrode of this invention, it is preferable that it is 1000 ohms / square or less as surface resistivity, and it is more preferable that it is 100 ohms / square or less. Furthermore, in order to apply to a current drive type optoelectronic device, it is preferably 50Ω / □ or less, particularly preferably 10Ω / □ or less. It is preferable that it is 10 ³ Ω / □ or less because it can function as a transparent electrode in various optoelectronic devices. The surface resistivity can be measured in accordance with, for example, JIS K 7194: 1994 (resistivity test method using a conductive plastic four-probe method), and can be easily performed using a commercially available surface resistivity meter. Can be measured.

  There is no restriction | limiting in particular in the thickness of the transparent electrode of this invention, Although it can select suitably according to the objective, Generally it is preferable that it is 10 micrometers or less, and transparency and a softness | flexibility improve, so that thickness becomes thin. More preferred.

[Transparent conductive layer]
As an aspect of the present invention, the conductive fiber is at least one selected from the group of metal nanowires and carbon nanotubes, and the conductive material is at least one selected from the group of conductive polymer and conductive metal oxide fine particles. Preferably it is a seed.

  The transparent conductive layer according to the present invention may contain a transparent binder material or additive in addition to the conductive fiber and the conductive material. The transparent binder material is not particularly limited as long as it is a transparent resin capable of forming a coating solution. For example, a polyester resin, a polystyrene resin, an acrylic resin, a polyurethane resin, an acrylic urethane resin, a polycarbonate resin, Cellulose resins, butyral resins, etc. can be used alone or in combination.

  The thickness of the transparent conductive layer according to the present invention varies depending on the shape and content of the conductive fiber or conductive material to be used, but as a rough guide, the average diameter of the conductive fiber is preferably 500 nm or less. It is preferable to reduce the thickness of the transparent conductive layer according to the present invention by a pressurizing method described later, because the network formation of conductive fibers in the thickness direction can be made dense.

[Surface smoothness]
In the present invention, Ry and Ra representing the smoothness of the surface of the transparent conductive layer mean Ry = maximum height (the difference in height between the top and bottom of the surface) and Ra = arithmetic mean roughness, JIS B601. It is a value according to the surface roughness specified in (1994). In the transparent electrode of the present invention, the smoothness of the surface of the transparent conductive layer is preferably Ry ≦ 50 nm, and the smoothness of the surface of the transparent conductive layer is preferably Ra ≦ 5 nm. In the present invention, for the measurement of Ry and Ra, a commercially available atomic force microscope (AFM) can be used. For example, it can be measured by the following method.

  Using an SPI 3800N probe station and SPA400 multifunctional unit manufactured by Seiko Instruments Inc. as the AFM, set the sample cut to a size of about 1 cm square on a horizontal sample stage on the piezo scanner, and place the cantilever on the sample surface. When approaching and reaching the region where the atomic force works, scanning is performed in the XY direction, and the unevenness of the sample at that time is captured by the displacement of the piezo in the Z direction. A piezo scanner that can scan XY 20 μm and Z 2 μm is used. The cantilever is a silicon cantilever SI-DF20 manufactured by Seiko Instruments Inc., which has a resonance frequency of 120 to 150 kHz and a spring constant of 12 to 20 N / m, and is measured in a DFM mode (Dynamic Force Mode). A measurement area of 80 × 80 μm is measured at a scanning frequency of 1 Hz.

  In the present invention, the value of Ry is more preferably 40 nm or less, and further preferably 30 nm or less. Similarly, the value of Ra is more preferably 3 nm or less, and further preferably 1 nm or less.

[Conductive fiber]
The conductive fiber according to the present invention is conductive and has a shape whose length is sufficiently longer than its diameter (thickness). The conductive fiber according to the present invention is considered to function as an auxiliary electrode by forming a three-dimensional conductive network when the conductive fibers contact each other in the transparent conductive layer. Accordingly, a longer conductive fiber is preferable because it is advantageous for forming a conductive network. On the other hand, when the conductive fibers are long, the conductive fibers are entangled to form aggregates, which may deteriorate the optical characteristics. Since the conductive fiber formation and aggregate formation are also affected by the stiffness and diameter of the conductive fibers, use the one with the optimum average aspect ratio (aspect = length / diameter) according to the conductive fibers used. Is preferred. As a rough guide, the average aspect ratio is preferably 10 to 10,000.

  Examples of the shape include a hollow tube shape, a wire shape, and a fiber shape, such as organic fibers and inorganic fibers coated with metal, conductive metal oxide fibers, metal nanowires, carbon fibers, and carbon nanotubes. In the present invention, from the viewpoint of transparency, it is preferable that the conductive fiber has a thickness of 300 nm or less, and in order to satisfy the conductivity, the conductive fiber is at least selected from the group of metal nanowires and carbon nanotubes. One type is preferable. Furthermore, silver nanowires can be most preferably used from the viewpoint of cost (raw material costs, manufacturing costs) and performance (conductivity, transparency, flexibility).

  In the present invention, the average value of the length, diameter, and aspect ratio of the conductive fiber can be obtained from an arithmetic average of measured values of individual conductive fiber images by taking an electron micrograph of a sufficient number of conductive fibers. it can. The length of the conductive fiber should be measured in a linearly stretched state, but in reality, it is often bent. It is also possible to calculate the projected area and assume a cylindrical body (length = projected area / projected diameter). The relative standard deviation of length and diameter is expressed by a value obtained by multiplying 100 by the value obtained by dividing the standard deviation of the measured value by the average value. The number of conductive fiber samples to be measured is preferably at least 100 or more, more preferably 300 or more.

Relative standard deviation [%] = standard deviation of measured value / average value × 100
[Metal nanowires]
In general, the metal nanowire refers to a linear structure having a metal element as a main component. In particular, the metal nanowire in the present invention means a linear structure having a diameter from the atomic scale to the nm size.

  As the metal nanowire applied to the conductive fiber according to the present invention, in order to form a long conductive path with one metal nanowire, the average length is preferably 3 μm or more, more preferably 3 to 500 μm, In particular, the thickness is preferably 3 to 300 μm. In addition, the relative standard deviation of the length is preferably 40% or less. Moreover, it is preferable that an average diameter is small from a transparency viewpoint, On the other hand, the larger one is preferable from an electroconductive viewpoint. In this invention, 10-300 nm is preferable as an average diameter of metal nanowire, and it is more preferable that it is 30-200 nm. In addition, the relative standard deviation of the diameter is preferably 20% or less.

  There is no restriction | limiting in particular as a metal composition of the metal nanowire which concerns on this invention, Although it can comprise from the 1 type or several metal of a noble metal element and a base metal element, noble metals (for example, gold, platinum, silver, palladium, rhodium, (Iridium, ruthenium, osmium, etc.) and at least one metal belonging to the group consisting of iron, cobalt, copper, and tin is preferable, and at least silver is more preferable from the viewpoint of conductivity. Further, in order to achieve both conductivity and stability (sulfurization and oxidation resistance of metal nanowires, and resistance to magnesium), it is also preferable to include silver and at least one metal belonging to a noble metal other than silver. When the metal nanowire according to the present invention includes two or more kinds of metal elements, for example, the metal composition may be different between the inside and the surface of the metal nanowire, or the entire metal nanowire has the same metal composition. May be.

  In the present invention, the means for producing the metal nanowire is not particularly limited, and for example, known means such as a liquid phase method and a gas phase method can be used. Moreover, there is no restriction | limiting in particular in a specific manufacturing method, A well-known manufacturing method can be used. For example, as a method for producing Ag nanowires, Adv. Mater. , 2002, 14, 833-837; Chem. Mater. , 2002, 14, 4736-4745, etc. As a method for producing Co nanowires, a method for producing Au nanowires is disclosed in JP 2006-233252A, and a method for producing Cu nanowires is disclosed in JP 2002-266007 A, etc. Reference can be made to Japanese Unexamined Patent Publication No. 2004-149871. In particular, Adv. Mater. And Chem. Mater. The method for producing Ag nanowires reported in (1) can be easily produced in an aqueous system, and since the conductivity of silver is the highest among metals, it is preferable as the method for producing metal nanowires according to the present invention. Can be applied.

〔carbon nanotube〕
A carbon nanotube is a carbon-based fiber material having a shape in which a graphite-like carbon atomic plane (graphene sheet) having a thickness of several atomic layers is wound into a cylindrical shape, and single-walled nanotubes (SWNT) and multilayers are formed from the number of peripheral walls. It is roughly divided into nanotubes (MWNT), and it is divided into a chiral type, a zigzag type, and an armchair type depending on the structure of the graphene sheet, and various types are known.

  As the carbon nanotube applied to the conductive fiber according to the present invention, any type of carbon nanotube can be used, and a mixture of these various carbon nanotubes may be used. An excellent single-walled carbon nanotube is preferable, and a metallic armchair-type single-walled carbon nanotube is more preferable.

  The shape of the carbon nanotube according to the present invention is preferably a single-walled carbon nanotube having a large aspect ratio (= length / diameter), that is, a thin and long carbon nanotube, in order to form a long conductive path with one carbon nanotube. . For example, carbon nanotubes having an aspect ratio of 102 or more, preferably 103 or more can be mentioned. The average length of the carbon nanotubes is preferably 3 μm or more, more preferably 3 to 500 μm, and particularly preferably 3 to 300 μm. In addition, the relative standard deviation of the length is preferably 40% or less. Moreover, it is preferable that an average diameter is smaller than 100 nm, 1-50 nm is preferable and it is more preferable that it is 1-30 nm. In addition, the relative standard deviation of the diameter is preferably 20% or less.

  The production method of the carbon nanotube used in the present invention is not particularly limited, and catalytic hydrogen reduction of carbon dioxide, arc discharge method, laser evaporation method, CVD method, vapor phase growth method, high temperature and high pressure of carbon monoxide. Well-known means such as HiPco method in which the reaction is carried out together with an iron catalyst and grown in the gas phase can be used. Moreover, in order to remove residues such as by-products and catalytic metals, carbon nanotubes that have been further purified by various purification methods such as washing methods, centrifugal separation methods, filtration methods, oxidation methods, chromatographic methods, etc. Is more preferable because various functions can be sufficiently expressed.

[Conductive material]
In the present invention, the conductive material is a material that can form a film having transparency and uniform conductivity in the formed state. Examples of such conductive materials include conductive polymers, conductive metal oxide fine particles, metal fine particles, organic fine particles coated with metal, inorganic fine particles, and the like. In the present invention, from the viewpoints of transparency and conductivity, the conductive material is preferably at least one selected from the group of conductive polymers and conductive metal oxide nanoparticles. Conductive polymers are particularly preferred.

[Conductive polymer]
Examples of the conductive polymer applied to the conductive material according to the present invention include, for example, polypyrrole, polyaniline, polythiophene, polythienylene vinylene, polyazulene, polyisothianaphthene, polycarbazole, polyacetylene, polyphenylene, polyphenylene vinylene, polyacene, Examples thereof include compounds selected from the group consisting of polyphenylacetylene, polydiacetylene and polynaphthalene derivatives.

  The conductive material according to the present invention may contain one type of conductive polymer alone, or may contain two or more types of conductive polymers in combination, From the viewpoint, polyaniline having a repeating unit represented by the following general formula (I) or general formula (II) or a derivative thereof, a polypyrrole derivative having a repeating unit represented by the following general formula (III), or the following general formula (IV It is more preferable that at least one compound selected from the group consisting of polythiophene derivatives having a repeating unit represented by

  In the above general formula (III) and general formula (IV), R is mainly a linear organic substituent, preferably an alkyl group, an alkoxy group, an allyl group, or a combination of these groups. As long as it does not lose its properties, a sulfonate group, an ester group, an amide group, or the like may be bonded to or combined with these. Note that n is an integer.

The conductive polymer according to the present invention can be subjected to a doping treatment in order to further increase the conductivity. As a dopant for the conductive polymer, for example, a sulfonic acid having a hydrocarbon group having 6 to 30 carbon atoms (hereinafter also referred to as a long-chain sulfonic acid) or a polymer thereof (for example, polystyrene sulfonic acid), a halogen atom , Lewis acid, proton acid, transition metal halide, transition metal compound, alkali metal, alkaline earth metal, MClO ₄ (M = Li ⁺ , Na ⁺ ), R ₄ N ⁺ (R═CH ₃ , C ₄ H ₉ , C ₆ H ₅ ), or R ₄ P ⁺ (R═CH ₃ , C ₄ H ₉ , C ₆ H ₅ ). Of these, the long-chain sulfonic acid is preferable.

  The dopant for the conductive polymer may be introduced into fullerenes such as hydrogenated fullerene, hydroxylated fullerene, and sulfonated fullerene. In the transparent conductive film, the dopant is preferably contained in an amount of 0.001 part by mass or more with respect to 100 parts by mass of the conductive polymer. Furthermore, it is more preferable that 0.5 mass part or more is contained.

The conductive material of the present invention includes a long-chain sulfonic acid, a polymer of long-chain sulfonic acid (for example, polystyrene sulfonic acid), halogen, Lewis acid, proton acid, transition metal halide, transition metal compound, alkali metal, Both at least one dopant selected from the group consisting of alkaline earth metals, MClO ₄ , R ₄ N ⁺ , and R ₄ P ⁺ and fullerenes may be included.

  As the conductive polymer according to the present invention, a conductive polymer modified with a metal disclosed in JP-T-2001-511581, JP-A-2004-99640, JP-A-2007-165199, or the like is used. You can also

  The conductive material containing the conductive polymer according to the present invention may contain a water-soluble organic compound. Among water-soluble organic compounds, compounds having an effect of improving conductivity by adding to a conductive polymer material are known, and 2nd. Sometimes called a dopant (or sensitizer). 2nd. Which can be used in the conductive material of the present invention. There is no restriction | limiting in particular in a dopant, It can select suitably from well-known things, For example, a dimethyl sulfoxide (DMSO), diethylene glycol, and another oxygen containing compound are mentioned suitably.

  In the conductive material containing the conductive polymer according to the present invention, the 2nd. 0.001 mass part or more is preferable, as for content of a dopant, 0.01-50 mass parts is more preferable, and 0.01-10 mass parts is especially preferable.

  The conductive material containing the conductive polymer according to the present invention may contain a transparent resin component or additive in addition to the conductive polymer in order to ensure film formability and film strength. The transparent resin component is not particularly limited as long as it is compatible or mixed and dispersed with the conductive polymer, and may be a thermosetting resin or a thermoplastic resin. For example, polyester resins such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate, polyimide resins such as polyimide and polyamideimide, polyamide resins such as polyamide 6, polyamide 6,6, polyamide 12 and polyamide 11, polyvinylidene fluoride, Fluorine resin such as polyvinyl fluoride, polytetrafluoroethylene, ethylene tetrafluoroethylene copolymer, polychlorotrifluoroethylene, etc., vinyl resin such as polyvinyl alcohol, polyvinyl ether, polyvinyl butyral, polyvinyl acetate, polyvinyl chloride, epoxy resin, xylene Resin, aramid resin, polyurethane resin, polyurea resin, melamine resin, phenol resin, polyether, acrylic resin and their co-polymer Body, and the like.

  A polyanion may be used for the conductive material in order to improve conductivity. Examples of the polyanion used in the present invention include compounds selected from the group consisting of polymeric carboxylic acids, polymeric sulfonic acids and derivatives of these salts, and preferred are polymeric sulfonic acids and salts thereof. The polyanions may be contained alone or in combination of two or more. The polyanion may form a copolymer with a structural unit having carboxylic acid or sulfonic acid and a monomer having no acid residue, such as acrylate, methacrylate, styrene, or the like.

  Specific examples of the polymer carboxylic acid, polymer sulfonic acid and salts thereof include, for example, polyacrylic acid, polymethacrylic acid or polymaleic acid, polymer sulfonic acid, polystyrene sulfonic acid and polyvinyl sulfonic acid and salts thereof. Polystyrene sulfonic acid and its salt are preferable.

[Binder resin that can be uniformly dispersed in aqueous solvents]
The present invention provides a transparent electrode having a transparent conductive layer having conductive fibers, a conductive polymer, and a binder resin on a transparent substrate, and the binder resin is a binder resin that can be uniformly dispersed in an aqueous solvent. It is characterized by.

  The binder resin that can be uniformly dispersed in the aqueous solvent according to the present invention is one that can be uniformly dispersed in the aqueous solvent. In the present invention, the phrase “uniformly dispersible in the aqueous solvent” means that the binder resin does not aggregate in the aqueous solvent. This means that colloidal particles made of a binder resin are dispersed. The size of the colloidal particles is generally about 0.001 to 1 μm (1 to 1000 μm).

  The colloidal particles can be measured with a light scattering photometer.

  The aqueous solvent is not only pure water (including distilled water and deionized water), but also an aqueous solution containing acid, alkali, salt, etc., a water-containing organic solvent, and a hydrophilic organic solvent. And pure water (including distilled water and deionized water), alcohol solvents such as methanol and ethanol, mixed solvents of water and alcohol, and the like.

  The binder resin that can be uniformly dispersed in the aqueous solvent according to the present invention is preferably transparent.

  The binder that can be uniformly dispersed in the aqueous solvent of the present invention is not particularly limited as long as it is a medium for forming a film. Examples of the binder that can be uniformly dispersed in the aqueous solvent include: acrylic resin emulsion, aqueous urethane resin, and the like. The acrylic resin emulsion is made of vinyl acetate, acrylic acid, a polymer of acrylic acid-styrene, or a copolymer with other monomers. In addition, the acid part is composed of a copolymer of an anionic lithium salt, sodium salt, potassium salt, ammonium salt, and a monomer having a nitrogen atom, and a cationic nitrogen atom forming a hydrochloride salt, Preferably it is anionic.

  Examples of aqueous urethane resins include water-dispersed urethane resins and ionomer-type aqueous urethane resins (anionic). The water-dispersed urethane resin includes a polyether-based urethane resin and a polyester-based urethane resin, preferably a polyester-based urethane resin.

  Examples of the ionomer-type water-based urethane resin include a polyester-based urethane resin, a polyether-based urethane resin, a polycarbonate-based urethane resin, and the like, preferably a polyester-based urethane resin and a polyether-based urethane resin.

  As commercial products, Boncoat AN-155-E, Boncoat AC-501, Boncoat AN-200, Boncoat R-3380-E (acrylic resin emulsion (anionic)), Bondick 1940NE (water-dispersed polyurethane resin, polyether) -Based urethane resin), Bondick 2210, Bondick 2220 (water-dispersed polyurethane resin, polyester-based urethane resin), Hydran 140SF, Hydran AP-40 (F), Hydran AP-40N (Ionomeric aqueous urethane resin, polyester-based urethane) Resin), Hydran HW-312B, Hydran WLS-201 (ionomer type water-based urethane resin, polyether urethane resin) (all manufactured by DIC) can be used. One or more binders that can be uniformly dispersed in the aqueous solvent can be used.

  As the usage-amount of the binder which can be uniformly disperse | distributed to the aqueous solvent of this invention, 1-200 mass% is preferable with respect to a conductive polymer, More preferably, it is 5-100 mass.

〔Production method〕
In the method for producing a transparent electrode of the present invention, there is no particular limitation on the method for forming an auxiliary electrode made of conductive fibers and a transparent conductive layer containing a conductive material on a transparent substrate, but improvement in productivity, smoothness, From the viewpoint of improving the electrode quality such as uniformity and reducing the environmental load, it is preferable to use a liquid phase film forming method such as a coating method or a printing method for forming the transparent conductive layer. As coating methods, roll coating method, bar coating method, dip coating method, spin coating method, casting method, die coating method, blade coating method, bar coating method, gravure coating method, curtain coating method, spray coating method, doctor coating method Etc. can be used. As the printing method, a letterpress (letter) printing method, a stencil (screen) printing method, a lithographic (offset) printing method, an intaglio (gravure) printing method, a spray printing method, an ink jet printing method, and the like can be used. In addition, as necessary, physical surface treatment such as corona discharge treatment or plasma discharge treatment can be applied to the surface of the releasable substrate as a preliminary treatment for improving the adhesion and coating properties.

  In the method for producing a transparent electrode of the present invention, after forming a transparent conductive layer containing conductive fibers and a conductive material on a release surface of a smooth release substrate, the transparent conductive layer is placed on the transparent substrate. It is preferable to use a method in which a transparent electrode is formed by transferring the film onto the surface. By using this method, the surface of the transparent conductive layer of the transparent electrode can be easily and stably highly smoothed.

  Preferred examples of the releasable substrate used in the method for producing a transparent electrode of the present invention include a resin substrate and a resin film. There is no restriction | limiting in particular in this resin, It can select suitably from well-known things, For example, synthesis | combination, such as a polyethylene terephthalate resin, a vinyl chloride resin, an acrylic resin, a polycarbonate resin, a polyimide resin, a polyethylene resin, a polypropylene resin A substrate or film composed of a single layer or multiple layers of resin is preferably used. Furthermore, a glass substrate or a metal substrate can also be used. Further, the surface (release surface) of the releasable substrate may be subjected to a surface treatment by applying a release agent such as silicone resin, fluororesin, or wax as necessary.

  Since the surface of the releasable substrate affects the smoothness of the surface after the transparent conductive layer is transferred, it is desirable that the surface of the releasable substrate be highly smooth. Specifically, Ry ≦ 50 nm is preferable, and Ry ≦ 40 nm. More preferably, Ry ≦ 30 nm is still more preferable. Further, Ra ≦ 5 nm is preferable, Ra ≦ 3 nm is more preferable, and Ra ≦ 1 nm is still more preferable.

  As a specific method for forming a transparent conductive layer excellent in smoothness including conductive fibers and a conductive material on a transparent substrate, for example, the following process can be exemplified.

  On the release surface of the release substrate, a conductive fiber dispersion is applied (or printed) and dried to form a conductive network structure made of conductive fibers. Next, a dispersion liquid of a conductive material is applied (or printed) on the network structure of the conductive fibers, and a conductive material is impregnated in a gap between the network structures of the conductive fibers on the substrate surface. A transparent conductive layer containing a conductive material is formed. Next, an adhesive layer is applied on the transparent conductive layer or another transparent substrate, and both are bonded together. After the adhesive layer is cured, the transparent conductive layer is transferred to the transparent substrate by peeling the release substrate.

  According to this process, since the conductive fiber network structure is three-dimensionally arranged in the conductive material layer, the contact area between the conductive fiber and the conductive material increases, and the auxiliary electrode function of the conductive fiber is sufficient. Therefore, a transparent conductive layer excellent in conductivity can be formed.

  In the above process, after applying and drying conductive fibers, calender treatment or heat treatment to increase the adhesion between the conductive fibers, or plasma treatment to reduce the contact resistance between the conductive fibers, This is effective as a method for improving the conductivity of the network structure of conductive fibers. In the above process, the release surface of the release substrate may be previously hydrophilized by corona discharge (plasma) or the like.

  In the above process, the adhesive layer may be provided on the releasable substrate side or on the transparent base material side. The adhesive used for the adhesive layer is not particularly limited as long as it is a material that is transparent in the visible region and has transfer ability. As long as it is transparent, a curable resin or a thermoplastic resin may be used.

  Examples of curable resins include thermosetting resins, ultraviolet curable resins, and electron beam curable resins. Among these curable resins, the equipment for resin curing is simple and excellent in workability. It is preferable to use an ultraviolet curable resin. The ultraviolet curable resin is a resin that is cured through a crosslinking reaction or the like by ultraviolet irradiation, and a component containing a monomer having an ethylenically unsaturated double bond is preferably used. For example, acrylic urethane type resin, polyester acrylate type resin, epoxy acrylate type resin, polyol acrylate type resin and the like can be mentioned. In the present invention, it is preferable that an acrylic or acrylic urethane-based ultraviolet curable resin is a main component as a binder.

  Acrylic urethane-based resins generally include 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate (hereinafter referred to as acrylates including methacrylates) to products obtained by reacting polyester polyols with isocyanate monomers or prepolymers. Can be easily obtained by reacting an acrylate monomer having a hydroxyl group such as 2-hydroxypropyl acrylate. For example, those described in JP-A-59-151110 can be used. For example, a mixture of 100 parts Unidic 17-806 (Dainippon Ink Co., Ltd.) and 1 part Coronate L (Nihon Polyurethane Co., Ltd.) is preferably used.

  Examples of UV curable polyester acrylate resins include those which are easily formed when 2-hydroxyethyl acrylate and 2-hydroxy acrylate monomers are generally reacted with polyester polyols. JP-A-59-151112 Can be used.

  Specific examples of the ultraviolet curable epoxy acrylate resin include an epoxy acrylate as an oligomer, a reactive diluent and a photoreaction initiator added to the oligomer, and a reaction. Those described in US Pat. No. 105738 can be used.

  Specific examples of UV curable polyol acrylate resins include trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, alkyl-modified dipentaerythritol pentaacrylate, etc. Can be mentioned.

  Examples of the resin monomer may include general monomers such as methyl acrylate, ethyl acrylate, butyl acrylate, benzyl acrylate, cyclohexyl acrylate, vinyl acetate, and styrene as monomers having one unsaturated double bond. In addition, monomers having two or more unsaturated double bonds include ethylene glycol diacrylate, propylene glycol diacrylate, divinylbenzene, 1,4-cyclohexane diacrylate, 1,4-cyclohexyldimethyl adiacrylate, and the above trimethylolpropane. Examples thereof include triacrylate and pentaerythritol tetraacryl ester.

  Among these, 1,4-cyclohexanediacrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane (meth) acrylate, trimethylolethane (meth) acrylate as the main component of the binder , An acrylic selected from dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,2,3-cyclohexanetetramethacrylate, polyurethane polyacrylate, polyester polyacrylate A system active ray curable resin is preferred.

  Specific examples of the photoinitiator of these ultraviolet curable resins include benzoin and its derivatives, acetophenone, benzophenone, hydroxybenzophenone, Michler's ketone, α-amyloxime ester, thioxanthone, and derivatives thereof. You may use with a photosensitizer. The photoinitiator can also be used as a photosensitizer. In addition, when using an epoxy acrylate photoinitiator, a sensitizer such as n-butylamine, triethylamine, or tri-n-butylphosphine can be used. The photoreaction initiator or photosensitizer used in the ultraviolet curable resin composition is 0.1 to 15 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the composition.

  The transparent conductive layer is made transparent by bonding (bonding) the release substrate formed with the transparent conductive layer and the transparent base material, curing the adhesive by irradiating ultraviolet rays and the like, and then peeling the release substrate. It can be transferred to the substrate side. Here, the bonding method is not particularly limited and can be performed by a sheet press, a roll press or the like, but is preferably performed using a roll press machine. The roll press is a method in which a film to be bonded is sandwiched between the rolls, and the rolls are rotated. The roll press is uniformly applied with pressure, and has a higher productivity than the sheet press and can be used preferably.

[Patterning method]
The transparent conductive layer according to the present invention can be patterned. There is no particular limitation on the patterning method or process, and a known method can be applied as appropriate. For example, a method of forming a patterned transparent electrode by forming a patterned transparent conductive layer on a release surface and then transferring it onto a transparent substrate can be used. Such a method can be preferably used.
i) A method of directly forming a transparent conductive layer according to the present invention in a pattern-like manner on a releasable substrate using a printing method.
ii) A method in which a transparent conductive layer according to the present invention is uniformly formed on a releasable substrate and then patterned using a general photolithography process.
iii) A method of patterning like a photolithography process after uniformly forming the transparent conductive layer according to the present invention using a conductive material containing, for example, an ultraviolet curable resin
iv) A method of uniformly forming a transparent conductive layer according to the present invention on a negative pattern previously formed of a photoresist on a releasable substrate and patterning it using a lift-off method. By transferring the transparent conductive layer patterned on the conductive substrate onto the transparent substrate, the patterned transparent electrode of the present invention can be formed.

[Preferred use]
The transparent electrode of the present invention has both high conductivity and transparency, and various optoelectronic devices such as liquid crystal display elements, organic light emitting elements, inorganic electroluminescent elements, electronic paper, organic solar cells, inorganic solar cells, electromagnetic wave shields, touch panels. It can be suitably used in such fields. Among these, it can use especially preferably as a transparent electrode of the organic electroluminescent element by which the smoothness of the surface of a transparent electrode is calculated | required severely.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "part by mass" or "mass%" is represented.

[Production of silver nanowires]
With reference to the method described in Non-Patent Document 2, silver nanowires were produced by the following method.

(Nucleation process)
While stirring 1000 ml of ethylene glycol (EG) liquid maintained at 170 ° C. in a reaction vessel, 100 ml of silver nitrate EG solution (silver nitrate concentration: 1.5 × 10 ⁻⁴ mol / L) was added at a constant flow rate for 10 seconds. did. Thereafter, aging was carried out at 170 ° C. for 10 minutes to form silver core particles. The reaction solution after completion of ripening exhibited a yellow color derived from surface plasmon absorption of silver nanoparticles, and it was confirmed that silver ions were reduced and silver nanoparticles were formed.

(Particle growth process)
The reaction solution containing the core particles after completion of the ripening is kept at 170 ° C. with stirring, and 1000 ml of an EG solution of silver nitrate (silver nitrate concentration: 1.0 × 10 ⁻¹ mol / L) and PVP K30 (molecular weight 50,000). 1000 ml of EG solution (PVP concentration conversion: 5.0 × 10 ⁻¹ mol / L) of ISP Co., Ltd. was added at a constant flow rate for 100 minutes using the double jet method. When the reaction solution was sampled every 20 minutes in the particle growth process and confirmed with an electron microscope, the silver nanoparticles formed in the nucleation process grew mainly in the long axis direction of the nanowires over time. No new core particles were observed in the grain growth process.

(Washing process)
After completion of the particle growth step, the reaction solution was cooled to room temperature, filtered using a filter, and the silver nanowires separated by filtration were redispersed in ethanol. Filtration of silver nanowires with a filter and redispersion in ethanol were repeated 5 times, and finally an aqueous dispersion of silver nanowires was prepared to produce silver nanowires.

  When a small amount of the obtained dispersion was collected and confirmed with an electron microscope, it was confirmed that silver nanowires having an average diameter of 85 nm and an average length of 7.4 μm were formed.

Example 1
[Preparation of Transparent Electrode TC-101; Present Invention]
The dispersion of silver nanowires was applied to a polyethylene terephthalate film support having a thickness of 100 μm that had been subjected to easy adhesion processing of the aqueous dispersion of silver nanowires so that the basis weight of the silver nanowires was 0.05 g / m ^2. It was applied and dried using a spin coater. Subsequently, the silver nanowire coating layer was calendered, and then a striped transparent pattern electrode TCF-1 having an electrode pattern width of 10 mm was produced by a known photolithography method.

  Next, Baytron PH510 (manufactured by HC Starck, solid content concentration 1.3%) which is a dispersion of PEDOT: PSS (polystyrene sulfonic acid) = 1: 2.5 as a conductive polymer (P- 1)), Boncoat AN-155E (manufactured by Dainippon Ink Co., Ltd., solid content concentration 55%), which is a binder resin that can be uniformly dispersed in an aqueous solvent, is 10% by mass with respect to the solid content of the conductive polymer. The thus added was applied and dried by a spin coater so that the dry film thickness was 300 nm, and a transparent electrode TC-101 was produced.

[Preparation of Transparent Electrode TC-102; Present Invention]
In the production of the transparent electrode TC-101, Boncoat AN-155E (manufactured by Dainippon Ink Co., Ltd., solid content concentration 55%), which is a binder resin that can be uniformly dispersed in an aqueous solvent, is a binder resin that can be uniformly dispersed in an aqueous solvent. A transparent electrode TC-102 was produced by performing the same operation except that Bondic 1940NE (Dainippon Ink Co., Ltd., solid content concentration: 50%) was used.

[Preparation of Transparent Electrode TC-103; Present Invention]
In the production of the transparent electrode TC-101, Boncoat AN-155E (manufactured by Dainippon Ink Co., Ltd., solid content concentration 55%), which is a binder resin that can be uniformly dispersed in an aqueous solvent, is a binder resin that can be uniformly dispersed in an aqueous solvent. A transparent electrode TC-103 was produced by performing the same operation except that Bondic 2210 (Dainippon Ink Co., Ltd., solid content concentration: 40%) was used.

[Preparation of Transparent Electrode TC-104; Present Invention]
In the production of the transparent electrode TC-101, Boncoat AN-155E (manufactured by Dainippon Ink Co., Ltd., solid content concentration 55%), which is a binder resin that can be uniformly dispersed in an aqueous solvent, is a binder resin that can be uniformly dispersed in an aqueous solvent. A transparent electrode TC-104 was produced in the same manner as described above except that it was replaced with Hydran AP-40 (F) (Dainippon Ink Co., Ltd., solid content concentration 22%).

[Preparation of Transparent Electrode TC-105; Present Invention]
In the production of the transparent electrode TC-101, after adding carboxymethyl cellulose (manufactured by Shin-Etsu Chemical Co., Ltd.) 25% to the silver nanowire dispersion and further adding 10% of the aldehyde-based crosslinking agent glyoxal to the carboxymethyl cellulose. A transparent electrode TC-105 was prepared in the same manner as above except that a silver nanowire dispersion liquid adjusted to pH 7.3 by adding sulfuric acid and ammonia was used.

[Preparation of Transparent Electrode TC-106; Present Invention]
In the production of the transparent electrode TC-101, 5% of carboxymethyl cellulose (manufactured by Shin-Etsu Chemical Co., Ltd.) is added to the silver nanowire dispersion per silver mass, and thermosetting resin-containing PEDOT Denatron G-2001A (manufactured by Nagase ChemteX Corporation) is added. ) Was used to produce a transparent electrode TC-106, except that a silver nanowire dispersion liquid containing 20% as a solid content was used.

[Preparation of Transparent Electrodes TC-107-112; Present Invention]
In the production of the transparent electrodes TC-101 to 106, Baytron PH510 (manufactured by HC Starck, solid content concentration: 1.2.5), which is a dispersion of the conductive polymer PEDOT: PSS (polystyrene sulfonic acid) = 1: 2.5. 3%) was replaced with polyaniline M (manufactured by TA Chemical Co., Ltd., solid content concentration 6.0%), and the same operation was performed to produce transparent electrodes TC-107 to 112.

[Preparation of Transparent Electrodes TC-113 and TC-114; Comparative Example]
In the production of the transparent electrodes TC-101 and TC-107, the same operation was performed except that Boncoat AN-155E (manufactured by Dainippon Ink Co., Ltd., solid content concentration 55%), which is a binder resin that can be uniformly dispersed in an aqueous solvent, was not added. Then, transparent electrodes TC-113 and TC-114 were produced.

[Preparation of Transparent Electrode TC-115; Comparative Example]
In the production of the transparent electrode TC-101, BONCOAT AN-155E (manufactured by Dainippon Ink Co., Ltd., solid concentration 55%), which is a binder resin that can be uniformly dispersed in an aqueous solvent, is used as a Byron UR-3220, which is a 30% polyurethane resin MEK solution. A transparent electrode TC-115 was produced in the same manner as described above except that it was replaced with (Toyobo Co., Ltd.).

<Evaluation>
With respect to the transparent electrodes TC-101 to TC-115 produced as described above, total light transmittance, surface resistivity, and surface smoothness (Ra, Ry) were determined by the following methods. Further, in order to evaluate the temporal stability of the transparent electrode, the total light transmittance, surface resistivity, and surface roughness (Ra, Ry) of the transparent electrode sample after a forced deterioration test placed in an environment of 80 ° C. and 90% RH for 3 days. ) Evaluated.

[Total light transmittance]
Based on JIS K 7361-1: 1997, it measured using the haze meter HGM-2B by Suga Test Instruments Co., Ltd.

[Surface resistance]
Based on JIS K7194: 1994, it measured using the Lorester GP (MCP-T610 type | mold) by Mitsubishi Chemical Corporation.

[Surface roughness (Ra, Ry)]
The surface roughness is specified in (JIS B601 (1994)) using a sample cut into a size of about 1 cm square using an AFM (SPI3800N probe station and SPA400 multifunctional unit manufactured by Seiko Instruments Inc.). According to the surface roughness to be measured.)

  The results are shown in Table 1.

In Table 1,
(Conductive polymer):
P-1: Baytron PH510 (poly (3,4-ethylenedioxythiophene) (containing polystyrene sulfonic acid as a dopant), manufactured by HC Starck, solid content concentration 1.3%)
P-2: Polyaniline M (polyaniline, manufactured by TA Chemical Co., Ltd., solid content concentration 6.0%)
(Binder resin that can be uniformly dispersed in an aqueous solvent):
Boncoat AN-155E: Acrylic resin emulsion (anionic) (Dainippon Ink Co., Ltd., solid content concentration 55%)
Bondic 1940NE: Water-dispersed polyurethane resin, polyether urethane resin (Dainippon Ink Co., Ltd., solid content concentration 50%)
Bondic 2210: Water-dispersed polyurethane resin, polyester urethane resin (Dainippon Ink Co., Ltd., solid content concentration 40%)
Hydran AP-40 (F): ionomer-type water-based urethane resin, polyester-based urethane resin (Dainippon Ink Co., Ltd., solid content concentration 22%)
(Binder resin that cannot be uniformly dispersed in an aqueous solvent):
Byron UR-3220 (30% polyurethane resin MEK solution, manufactured by Toyobo Co., Ltd.) (binder resin that cannot be uniformly dispersed in an aqueous solvent)
From the results shown in Table 1, it can be seen that in the case of the present invention, the transparent electrode is excellent in temporal stability (total light transmittance, surface resistivity, surface smoothness (Ra, Ry)).

  Transparent electrodes TC-113 to TC-115 coated with only a conductive polymer or only a binder resin that can be uniformly dispersed in an aqueous solvent on silver nanowires are surfaces after being placed in an environment of 80 ° C. and 90% RH for 3 days. It was revealed that the resistance and surface smoothness were poor and the surface resistance and surface smoothness of the transparent electrodes TC-101 to 112 of the present invention were more stable.

Example 2
[Preparation of Transparent Electrode TC-201; Present Invention]
Baytron PH510 (H), which is a dispersion of PEDOT: PSS (polystyrene sulfonic acid) = 1: 2.5, which is concentrated as a conductive polymer in the produced silver nanowire dispersion liquid by a rotary evaporator until the solid content concentration becomes 13%. Boncoat AN-155E (manufactured by Dainippon Ink Co., Ltd., solid content concentration 55%), which is a binder resin that can be uniformly dispersed in an aqueous solvent. Was added so that it might become 10 mass% with respect to solid content of a conductive polymer. This dispersion was applied on a polyethylene terephthalate film support having a thickness of 100 μm that had been subjected to easy adhesion processing, and dried by a spin coater so that the dry film thickness was 300 nm.
<Preparation of metal nanowire remover BF-1>
Ethylenediaminetetraacetic acid ferric ammonium 60g
Ethylenediaminetetraacetic acid 2g
Sodium metabisulfite 15g
70g ammonium thiosulfate
Maleic acid 5g
The metal nanowire remover BF-1 was prepared by finishing to 1 L with pure water and adjusting the pH to 5.5 with sulfuric acid or ammonia water.

  Subsequently, a calender treatment was applied to the silver nanowire coating layer, and then a gravure coating machine K printing proofer (manufactured by Matsuo Sangyo Co., Ltd.) was attached with a plate having a printing pattern opposite to the 10 mm stripe pattern. The viscosity of the metal nanowire remover BF-1 was adjusted as appropriate with CMC (carboxymethylcellulose, Sigma-Aldrich), and gravure printing was performed by adjusting the number of printings so that the coating film thickness was 30 μm on the silver nanowire coating layer. It was. After printing, it was left for 1 minute, and then washed with running water to produce a transparent electrode TC-201.

[Preparation of Transparent Electrode TC-202; Present Invention]
In the production of the transparent electrode TC-201, Boncoat AN-155E (manufactured by Dainippon Ink Co., Ltd., solid content concentration 55%), which is a binder resin that can be uniformly dispersed in an aqueous solvent, is bonded to Bondic 1940NE (manufactured by Dainippon Ink Co., Ltd., solid content). A transparent electrode TC-202 was produced in the same manner except that the concentration was changed to 50%.

[Preparation of Transparent Electrode TC-203; Present Invention]
In the production of the transparent electrode TC-201, Boncoat AN-155E (manufactured by Dainippon Ink Co., Ltd., solid content concentration 55%), which is a binder resin that can be uniformly dispersed in an aqueous solvent, is bonded to Bondic 2210 (manufactured by Dainippon Ink Co., Ltd., solid content). A transparent electrode TC-203 was produced in the same manner except that the concentration was changed to 40%.

[Preparation of Transparent Electrode TC-204; Present Invention]
In the production of the transparent electrode TC-201, Boncoat AN-155E (manufactured by Dainippon Ink Co., Ltd., solid content concentration 55%), which is a binder resin that can be uniformly dispersed in an aqueous solvent, was applied to Hydran AP-40 (F) (Dainippon Ink Co., Ltd.). A transparent electrode TC-204 was produced in the same manner except that the product was replaced with a solid content concentration of 22%.

[Preparation of Transparent Electrode TC-205; Present Invention]
In the production of the transparent electrode TC-201, 25% carboxymethylcellulose (manufactured by Shin-Etsu Chemical Co., Ltd.) is added to the silver nanowire dispersion, and 10% of the aldehyde-based crosslinking agent glyoxal is added to the carboxymethylcellulose. A transparent electrode TC-205 was produced in the same manner as above except that a silver nanowire dispersion liquid adjusted to pH 7.3 by adding sulfuric acid and ammonia was used.

[Preparation of Transparent Electrode TC-206; Present Invention]
In the production of the transparent electrode TC-201, 5% of carboxymethyl cellulose (manufactured by Shin-Etsu Chemical Co., Ltd.) is added to the silver nanowire dispersion per silver mass, and further, a thermosetting resin-containing PEDOT Denatron G-2001A (manufactured by Nagase ChemteX Corporation). ) Was used in the same manner except that a silver nanowire dispersion liquid added with 20% as a solid content was used to produce a transparent electrode TC-206.

[Production of Transparent Electrodes TC-207 to 212; Present Invention]
In the production of the transparent electrodes TC-201 to 206, Baytron PH510 (manufactured by HC Starck, solid content concentration 1.3%) which is a dispersion of PEDOT: PSS (polystyrene sulfonic acid) = 1: 2.5 is used. Transparent electrodes TC-207 to 212 were prepared in the same manner except that the polyaniline M (manufactured by TA Chemical Co., Ltd., solid content concentration 6.0%) was used.

[Preparation of Transparent Electrodes TC-213 and TC-214; Comparative Example]
In the production of the transparent electrodes TC-201 and TC-207, the same operation was performed except that Boncoat AN-155E (manufactured by Dainippon Ink Co., Ltd., solid content concentration 55%), which is a binder resin that can be uniformly dispersed in an aqueous solvent, was not added. Then, transparent electrodes TC-213 and TC-214 were produced.

[Preparation of Transparent Electrode TC-215; Comparative Example]
In the production of the transparent electrode TC-201, BONCOAT AN-155E (manufactured by Dainippon Ink and Co., Ltd., solid content concentration 55%), which is a binder resin that can be uniformly dispersed in an aqueous solvent, is used by Byron UR-3220, which is a 30% polyurethane resin MEK solution. A transparent electrode TC-215 was produced in the same manner as described above except that it was replaced with (Toyobo Co., Ltd.).

<Evaluation>
With respect to the transparent electrodes TC-201 to TC-215 produced as described above, the total light transmittance, the surface resistivity, and the surface smoothness (Ra, Ry) were determined by the method described in Example 1. In addition, in order to evaluate the stability of the transparent electrode, the total light transmittance, surface resistivity, and surface smoothness (Ra, Ry) of the transparent electrode sample after the forced deterioration test placed in an environment of 80 ° C. and 90% RH for 3 days. , Also asked for.

  The results are shown in Table 2.

  From Table 2, in the case of this invention, it turns out that it is excellent in the temporal stability (total light transmittance, surface resistivity, surface smoothness (Ra, Ry)) of a transparent electrode.

  Transparent electrodes TC-213 to TC-215 in which only a conductive polymer or only a binder resin that can be uniformly dispersed in an aqueous solvent are coated on silver nanowires are surfaces after being placed in an environment of 80 ° C. and 90% RH for 3 days. It was revealed that the resistance and surface smoothness were poor and the surface resistance and surface smoothness of the transparent electrodes TC-201 to TC-212 of the present invention were more stable.

Example 3
[Production of organic electroluminescence element (organic EL element)]
Using the produced transparent electrodes TC-101 to 115 as the first electrode (anode electrode), organic EL elements OEL-301 to 315 were produced in the following procedure.
<Formation of hole transport layer>
On the first electrode, 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), which is a hole transport material, was added to 1% by mass in 1,2-dichloroethane. The dissolved coating solution for forming a hole transport layer was applied by a spin coater and then dried at 80 ° C. for 60 minutes to form a hole transport layer having a thickness of 40 nm.
<Formation of light emitting layer>
On each film in which the hole transport layer is formed, the red dopant material Btp ₂ Ir (acac) is 1% by mass and the green dopant material Ir (ppy) ₃ is 2% with respect to polyvinylcarbazole (PVK) as the host material. %, Blue dopant material FIr (pic) is mixed so as to be 3% by mass, and the light emission is dissolved in 1,2-dichloroethane so that the total solid concentration of PVK and the three dopants is 1% by mass. The coating liquid for layer formation was applied with a spin coater and then dried at 100 ° C. for 10 minutes to form a light emitting layer having a thickness of 60 nm.

<Formation of electron transport layer>
On the formed light emitting layer, LiF was evaporated as a material for forming an electron transport layer under a vacuum of 5 × 10 ⁻⁴ Pa to form an electron transport layer having a thickness of 0.5 nm.
<Formation of second electrode>
On the formed electron carrying layer, Al was vapor-deposited as a 2nd electrode formation material under the vacuum of 5 * 10 <^-4> Pa, and the 2nd electrode with a thickness of 100 nm was formed.
<Formation of sealing film>
On the formed electron transport layer, a polyethylene terephthalate as a substrate, using a flexible sealing member which is deposited to a thickness 300nm of Al ₂ O _3. Apply the adhesive around the second electrode except for the end so that the external lead terminals of the first electrode and the second electrode can be formed, paste the flexible sealing member, and then cure the adhesive by heat treatment It was.

[Light emission uniformity (light emission unevenness)]
Using a source measure unit 2400 made by KEITHLEY, a direct current voltage was applied to the organic EL element to emit light in an environment of 23 ± 3 ° C. and 55 ± 3% RH. Regarding the organic EL elements OEL-301 to OEL-315 that emitted light at 200 cd / m ² , the respective light emission uniformity was observed with a 50 × microscope. In addition, after heating the organic EL elements OEL-301 to OEL-315 in an oven at 80 ° C. and 60% RH for 30 minutes, the humidity was adjusted again in the environment of 23 ± 3 ° C. and 55 ± 3% RH for 1 hour or more. Similarly, the emission uniformity was observed.

Evaluation Criteria for Emission Uniformity ◎: The entire EL element emits light uniformly ○: The entire EL element emits light almost uniformly Δ: Some unevenness is observed in the light emission of the EL element x: Light emission of the EL element Obvious unevenness is observed Table 3 shows the evaluation results.

  From Table 3, the organic EL elements OEL-313 to OEL-315 are significantly deteriorated in light emission uniformity after heating (forced deterioration) at 80 ° C. and 60% RH for 30 minutes, whereas the organic EL elements OEL-301 to OEL of the present invention It was revealed that the emission uniformity of −312 was stable even after heating.

Example 4
[Production of organic electroluminescence element (organic EL element)]
Using the produced transparent electrodes TC-201 to 215 as first electrodes, organic EL elements OEL-401 to 415 were produced in the same manner as in the procedure of Example 3.

  The evaluation results are shown in Table 4.

  From Table 4, the organic EL elements OEL-413 to OEL-415 are significantly degraded in light emission uniformity after heating at 80 ° C. and 60% RH for 30 minutes, whereas the organic EL elements OEL-401 to OEL-412 of the present invention emit light. It became clear that the uniformity was stable even after heating.

11 Conductive fiber 21 Conductive material 31 Transparent conductive layer 3
41 Transparent resin 51 Transparent substrate

Claims (11)

In a transparent electrode having a transparent conductive layer having a conductive fiber, a conductive polymer, and a binder resin on a transparent substrate,
A transparent electrode, wherein the binder resin is a binder resin that can be uniformly dispersed in an aqueous solvent.   The transparent electrode according to claim 1, wherein the transparent conductive layer on the transparent substrate contains a binder resin that can be uniformly dispersed in the conductive fiber, the conductive polymer, and the aqueous solvent.   A second transparent conductive material on the first transparent conductive layer containing the conductive fiber in a first transparent conductive layer on a transparent substrate and a binder resin that can be uniformly dispersed in the conductive polymer and an aqueous solvent. The transparent electrode according to claim 1, wherein the transparent electrode is contained in a layer.   The transparent electrode according to claim 1, wherein the conductive fiber is a silver nanowire.   The transparent electrode according to claim 1, wherein the binder resin that can be uniformly dispersed in the aqueous solvent is at least one selected from an acrylic resin and a urethane resin. In the method for producing a transparent electrode having a transparent conductive layer having a conductive fiber, a conductive polymer, and a binder resin on a transparent substrate,
A method for producing a transparent electrode, wherein the binder resin is a binder resin that can be uniformly dispersed in an aqueous solvent.   A transparent conductive layer is formed by applying an aqueous dispersion containing a conductive resin, a conductive polymer, and a binder resin that can be uniformly dispersed in an aqueous solvent onto a transparent substrate. Item 7. A method for producing a transparent electrode according to Item 6. Applying a first transparent conductive layer containing the conductive fibers on a transparent substrate;
Forming a second transparent conductive layer by applying an aqueous dispersion containing a binder resin that can be uniformly dispersed in the conductive polymer and an aqueous solvent on the first transparent conductive layer;
The method for producing a transparent electrode according to claim 6, comprising:   The method for producing a transparent electrode according to claim 6, wherein the conductive fiber is a silver nanowire.   The transparent electrode production according to any one of claims 6 to 9, wherein the binder resin that can be uniformly dispersed in the aqueous solvent is at least one selected from an acrylic resin and a urethane resin. Method.   An organic electroluminescence device comprising the transparent electrode according to claim 1.

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