JP5181793B2 - Transparent conductive film and method for producing the same, and organic electroluminescence device - Google Patents

Description

  The present invention relates to a transparent conductive film which is excellent in conductivity, transparency and flexibility, has high smoothness and is inexpensive, and a method for producing the same.

  As a transparent conductive film applied to liquid crystal displays, electroluminescence displays, plasma displays, electrochromic displays, solar cells, electronic paper, touch panels, etc., indium-tin composite oxide (ITO) has been conventionally used as polyethylene terephthalate (PET). An ITO film provided by a vacuum deposition method or a sputtering method on a transparent film such as polyethylene naphthalate (PEN) has been mainly used.

  However, in order to obtain a low resistance, it is necessary to form a thick and uniform film or to perform a high-temperature treatment. Therefore, there is a limit to compatibility with the transmittance, cost, and low resistance in the film. In order to solve this problem, it is known to use an auxiliary electrode composed of a metal pattern having an opening (see, for example, Patent Document 1). However, in this method, although conductivity is obtained, the smoothness of the surface is insufficient, and the barrier property is not sufficiently lowered. In particular, when used for an organic electroluminescence element, an organic thin film solar cell, or the like, there is a concern about dark spots, a decrease in conversion efficiency, and the like.

  On the other hand, as a method for improving the smoothness of the surface, there is known a so-called transfer method in which a transparent conductive layer is once formed on a smooth temporary support and then copied onto a film support with a resin layer (for example, a patent). Reference 2). However, when these inorganic oxides (ITO, IZO, etc.) are used, there is no flexibility, so problems such as cracks are likely to occur during transfer. In particular, when an auxiliary electrode is used to improve conductivity, a sufficiently satisfactory one is difficult to obtain because the unevenness between the auxiliary electrode portion and the opening is large.

Further, as a method for transferring a metal pattern, a method of transferring a grid-like fine metal wiring pattern produced by a silver halide diffusion transfer method onto glass epoxy or soda lime glass is disclosed (for example, see Patent Document 3). However, in this method, in-plane uniformity is poor, and light emission unevenness or the like of the organic electrochromic element occurs.
JP 2006-352073 A JP 2006-236626 A JP 2006-1111889 A

  The present invention has been made in view of the above-described problems and circumstances, and the solution to the problem is a transparent conductive film that is excellent in conductivity, transparency, and flexibility, has high smoothness, and is inexpensive. Is to provide a method.

  In the process of earnestly studying to solve the above-mentioned problems, the inventors of the present application improve the conductivity and smooth the surface using a metal pattern auxiliary electrode having an opening, particularly in the study of an organic electroluminescence element and an organic thin film solar cell. We found that compatibility of sex is important.

  In general, the “auxiliary electrode” is an electrode provided to lower the resistance value of an electrode having insufficient conductivity, and may be referred to as a bus electrode.

  The present inventors have reached the present invention by obtaining the above knowledge. That is, the said subject which concerns on this invention is solved by the following means.

1. A transparent conductive film having an auxiliary electrode composed of a metal pattern having an opening on a transparent support, and a transparent conductive layer containing conductive fibers, wherein the surface roughness on the opposite side of the transparent support A transparent conductive film having a thickness Ra ( _S ) of 5 nm or less.

  2. 2. The transparent conductive film according to 1 above, wherein a large number of conductive fibers of the transparent conductive layer are present on the side far from the transparent support.

  3. 3. The transparent conductive film as described in 1 or 2 above, wherein the conductive fiber contains carbon nanotubes or metal nanowires.

  4). It has the transparent conductive film of any one of said 1-3, The organic electroluminescent element characterized by the above-mentioned.

  5. It is a manufacturing method of the transparent conductive film of any one of said 1-3, After laminating | stacking the transparent conductive layer containing the said auxiliary electrode and a conductive fiber in this order on a releasable support body previously. The method for producing a transparent conductive film, wherein the auxiliary electrode and the transparent conductive layer are transferred to a transparent support.

  By the above means of the present invention, it is possible to provide a transparent conductive film which is excellent in conductivity, transparency and flexibility, has high smoothness and is inexpensive, and a method for producing the same.

  That is, according to the means of the present invention, it is possible to provide a highly flexible transparent conductive film that can be preferably applied to an organic electroluminescence element, an organic thin film solar cell, and the like, and a method for producing the same.

  The present invention will be described in more detail.

The transparent conductive film of the present invention is a transparent conductive film having an auxiliary electrode composed of a metal pattern having an opening on a transparent film substrate and a conductive layer containing conductive fibers, and the surface thereof Roughness Ra ( _S ) is 5 nm or less, It is characterized by the above-mentioned. This feature is a technical feature common to the inventions according to claims 1 to 5.

  In the present application, “transparent” means that the total light transmittance in the visible light wavelength region measured by a method in accordance with JIS K 7361-1: 1997 (plastic-transparent material total light transmittance test method) is 70. % Or more.

  Preferred embodiments of the present invention include a large amount of conductive fibers on the side far from the transparent support, and the conductive fibers containing carbon nanotubes or metal nanowires.

  As a method for producing the transparent conductive film of the present invention, a metal pattern auxiliary electrode and a conductive layer containing conductive fibers are previously laminated in this order on a releasable support, and then the auxiliary electrode and the conductive layer are transparently supported. A method of transferring and forming on a body is more preferable.

  The transparent conductive film of the present invention is preferably used for an organic electroluminescence device in which smoothness is particularly required.

  Hereinafter, the present invention, its components, and the best mode for carrying out the present invention will be described in detail.

[Transparent film substrate]
A plastic film can be used as the transparent film substrate used in the present invention.

  Examples of the raw material for the plastic film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate, polyolefins such as polyethylene (PE), polypropylene (PP), polystyrene, and cyclic olefin resins, polyvinyl chloride, and polychlorinated chloride. Use vinyl resins such as vinylidene, polyether ether ketone (PEEK), polysulfone (PSF), polyether sulfone (PES), polycarbonate (PC), polyamide, polyimide, acrylic resin, triacetyl cellulose (TAC), etc. Can do.

  Of these, a biaxially stretched polyethylene terephthalate film, an acrylic resin film, and a triacetylcellulose film are preferable, and a biaxially stretched polyethylene terephthalate film is most preferable in terms of transparency, heat resistance, ease of handling, and cost.

  The transparent film substrate is preferably provided with a surface treatment or an easy-adhesion layer in order to ensure wettability and adhesion of the coating solution. Conventionally known techniques can be used for the surface treatment and the easy-adhesion layer, but when the transparent film substrate is a biaxially stretched polyethylene terephthalate film, the refractive index of the easy-adhesion layer adjacent to the film is 1.57-1. By setting it to 63, the interface reflection between the film substrate and the easy adhesion layer can be reduced and the transmittance can be improved, which is more preferable. As a method for adjusting the refractive index, the refractive index can be prepared 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 in order to improve the adhesiveness, it may be composed of two or more layers.

[Auxiliary electrode]
The “auxiliary electrode” in the present invention can function as an auxiliary electrode for the entire transparent conductive film. In the auxiliary electrode according to the present invention, a line made of a metal material such as a single metal or alloy is arranged on a transparent film substrate in a uniform mesh shape, a straight or curved stripe shape, a comb shape, or the like. Objects, triangles such as regular triangles, isosceles triangles, right triangles, squares, rectangles, rhombuses, parallelograms, trapezoids and other quadrangles, (positive) hexagons, (positive) n-gons such as (positive) octagons, It can be configured by a regular combination of geometric pattern line patterns combining circles, ellipses, stars, etc., irregular shapes, irregular patterns, and the like.

  There is no restriction | limiting in particular as a metal composition, Although it can be comprised from 1 type or multiple metals of a noble metal element and a base metal element, it is noble metal (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, tin and nickel, and more preferably at least silver from the viewpoint of conductivity. Furthermore, in order to achieve both conductivity and stability, it is also preferable that silver and at least one metal other than silver be included.

Since the auxiliary electrode according to the present invention functions as a main power supply path to the entire film, it is preferable that the resistivity is low. To the resistivity low, it is effective to increase the line cross-sectional area of the auxiliary electrode patterns, line average cross-sectional area of the auxiliary electrode in the present invention is preferably a 1μm ² ~500μm ^2. In the case of the same line cross-sectional area, it is preferable to increase the thickness of the line because both transparency and conductivity can be achieved. The surface resistivity of the auxiliary electrode alone is preferably 10Ω / □ or less, more preferably 5Ω / □ or less, and particularly preferably 1Ω / □ or less.

  On the other hand, from the viewpoint of transparency, it is preferable to increase the aperture ratio (the ratio of the area of the auxiliary electrode where there is no metal line pattern to the total area), that is, the line width is narrow and the line interval is wide. The aperture ratio of the auxiliary electrode is preferably 80% or more, and most preferably 90% or more.

  Thus, from the viewpoint of conductivity and transparency, the line width and thickness are preferably 1 μm to 100 μm, and the line interval is preferably 50 μm to 1000 μm.

  As a method of forming the auxiliary electrode, a known method can be used. For example, pattern formation method by photolithography method, printing method, ink jet method, method of forming pattern by exposure and development using silver salt photosensitive material, coating and drying with metal colloid that spontaneously forms pattern when drying May be. Further, electroless plating or electrolytic plating may be used in combination with the above method. Among these, a printing method, an inkjet method (particularly an electrostatic inkjet method), a method using a silver salt photosensitive material, a metal colloid coating that spontaneously forms a pattern, or a method using these in combination with electroless plating or electrolytic plating, The auxiliary electrode is preferable because it can be continuously formed with high accuracy at low cost.

[Transparent conductive layer]
The “transparent conductive layer” according to the present invention is characterized by containing conductive fibers.

  Here, the “conductive fiber” is conductive and has a shape that is sufficiently long compared to the width, and generally has a length to width ratio (aspect ratio) of 5 or more, preferably Is 20 or more. 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, a conductive fiber having a thickness of 300 nm or less is preferable from the viewpoint of transparency, and at least metal nanowires and carbon nanotubes are preferably included in order to satisfy conductivity.

  The average diameter and average length of the conductive fibers according to the present invention are obtained by taking an electron micrograph of a sufficient number of conductive fibers using SEM or TEM, and from the arithmetic average of the measured values of the individual conductive fiber images. Can be sought. The length of the conductive fiber should originally be obtained in a linearly stretched state, but since it is often bent in reality, the projected diameter of the conductive fiber using an image analyzer from an electron micrograph is used. And the projected area is calculated, assuming a cylindrical body (length = projected area / projected diameter). The number of conductive fibers to be measured is preferably at least 100, more preferably 300 or more.

  The conductive fiber layer forming method according to the present invention is not particularly limited, and is formed by applying a coating solution in which conductive fibers are dispersed in a solution obtained by dissolving a binder resin in water or an organic solvent on a transparent film. However, in order to achieve both conductivity and transparency, only conductive fibers dispersed in water or organic solvents are deposited on the transparent film, and then the binder solution so that the conductive fibers protrude from the surface. It is more preferable to form by coating. Moreover, after apply | coating a conductive fiber, before apply | coating a binder solution, it is also preferable to carry out a calendar process once with a roller etc. and to improve the adhesiveness of conductive fibers.

[Metal nanowires]
The metal nanowire according to the present invention may be a nanoscale metal wire, but the average diameter is preferably 200 nm or less from the viewpoint of transparency, and preferably 10 nm or more from the viewpoint of conductivity. More preferably, it is 30-180 nm. The average length is preferably 1 μm or more from the viewpoint of conductivity, preferably 500 μm or less, more preferably 3 to 300 μm, from the influence on the transparency due to aggregation.

  Although there is no restriction | limiting in particular as a metal element of the metal nanowire which concerns on this invention, As a metal element of the metal nanowire which can be used preferably, Ag, Cu, Au, Al, Rh, Ir, Co, Zn, Ni, In , Fe, Pd, Pt, Sn, Ti and the like, and Ag 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 at least one kind of metal belonging to noble metal other than silver and silver. When the metal nanowire 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 may have the same alloy composition.

  In the present invention, there are no particular limitations on the means for producing the metal nanowires, and known means such as a liquid phase method and a gas phase method can be used. In particular, Ag nanowires are used in polyols such as ethylene glycol and polyvinylpyrrolidone. Therefore, Ag nanowires having a uniform shape can be synthesized in a large amount by a liquid phase method for reducing a silver salt such as silver nitrate. Examples of the synthesis method include Xia. Y, et. al. , Chem. Mater. Journal Volume 14, 2002, p. 4736-4745 and Xia. Y, et. al. , Nanoletters, Vol. 3, 2003, p. 955-960.

〔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.

Any of the above types can be used as the carbon nanotube according to the present invention, but it is preferable to use a single-walled nanotube having a large aspect ratio, that is, a thin and long one. For example, carbon nanotubes having an aspect ratio of 10 ³ or more, preferably 10 ⁴ or more can be mentioned. The length of the carbon nanotube is usually 1 μm or more, preferably 50 μm or more, more preferably 500 μm or more, and the upper limit of the length is not particularly limited, but is, for example, about 10 mm. As the outer diameter, extremely minute carbon nanotubes on the order of nm are known. The carbon nanotubes are preferably surface-treated with an organic compound, and specifically, it is preferable to improve the dispersibility of each primary particle using a surfactant. In addition, the diameter distribution is preferably 20% or less. A mixture of these various carbon nanotubes may be used.

  The method for producing the carbon nanotube used in the present invention is not particularly limited. Specifically, catalytic hydrogen reduction of carbon dioxide, arc discharge method, laser evaporation method, CVD method, vapor phase growth method, HiPco method in which carbon monoxide is reacted with an iron catalyst at high temperature and high pressure to grow in the gas phase, etc. Is mentioned. 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 are sufficiently exhibited.

  The method for forming the transparent conductive layer according to the present invention is not particularly limited, but roll coating, bar coating, dip coating, spin coating, casting, die coating, blade coating, bar coating, gravure, and the like. Coating method, curtain coating method, spray coating method, doctor coating method, etc., letterpress (letter) printing method, stencil (screen) printing method, planographic (offset) printing method, intaglio (gravure) printing method, spray printing It is preferable to use a printing method such as an ink jet printing method.

  As a preferred embodiment of the present invention, it is preferable that many conductive fibers exist on the side far from the transparent support. When the transparent conductive film is observed from the side as shown in the schematic cross-sectional view of FIG. 1, the conductive fiber is present on the surface farther from the middle of the transparent support and the surface. It is to contain 50% or more on the side. Preferably, it contains 80% or more, more preferably 90% or more. As a method of containing a large amount on the surface side, after forming a metal pattern auxiliary electrode, a transparent resin is formed so as to have a thickness of 50% or more with respect to the height of the auxiliary electrode, and a conductive fiber is included thereon. A method of forming a transparent conductive layer, or after previously laminating a metal pattern auxiliary electrode and a transparent conductive layer containing conductive fibers on a releasable support in this order, and then transferring the auxiliary electrode and the transparent conductive layer to the transparent support There is a method of forming.

  Further, the transparent conductive film of the present application is formed by forming a transparent conductive layer including a metal pattern auxiliary electrode and conductive fibers as described above, and then a conductive metal oxide such as a conductive conductive polymer or ITO or ZnO on the surface thereof. You may form the layer which consists of.

(Releasable support)
Suitable examples of the releasable support 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. Further, a glass substrate or paper can be used.

The surface of the releasable support is preferably highly smooth because it affects the surface roughness of the conductive layer after the transparent conductive layer is transferred, and the surface smoothness Ra ( _S ) ≦ 5 nm. ( _S ) ≦ 3 nm is more preferable, and Ra ( _S ) ≦ 1 nm is still more preferable.

  In addition, a surface treatment may be performed on the surface (release surface) of the releasable support by applying a release agent such as silicone resin, fluororesin, or wax as necessary.

[Other additives]
In addition to the various components described above, the transparent conductive layer according to the present invention can optionally contain additives as necessary. Specific examples include surfactants, organic solvents, ultraviolet absorbers, antioxidants, deterioration inhibitors, pH adjusters, polymerization inhibitors, surface modifiers, defoamers, plasticizers, antibacterial agents, and the like. It is done. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the surfactant include generally known anionic surfactants, cationic surfactants, amphoteric surfactants, nonionic surfactants, and the like. good. In the present invention, it may be advantageous to use an aqueous solvent for forming a conductive film, which will be described later. In this case, in particular, a polycondensation type aromatic surfactant, a polymerization type aromatic interface, and the like. It is also one of preferred embodiments to use an activator, an aromatic nonionic surfactant, a combination of an aromatic nonionic surfactant and an ionic surfactant, and the like.

[Transparent conductive film]
The transparent conductive film of the present invention preferably has a conductive surface smoothness Ra ( _S ) ≦ 5 nm, more preferably Ra ( _S ) ≦ 3 nm, and Ra ( _S ) ≦ 1 nm. More preferably.

Here, Ra ( _S ) means arithmetic average roughness (average value of absolute value deviations from the average line), and the smaller the value, the better the smoothness. Ra ( _S ) can be measured and determined using a surface roughness meter or the like if it can be directly measured. Alternatively, a cross section perpendicular to the transparent conductive film is prepared with a microtome, an electron micrograph of 10 sections or more is taken, and the surface roughness curve is measured using an image processing apparatus or the like, and the arithmetic average roughness is calculated. It can also be calculated.

  In order to smooth the surface of a transparent conductive film having a metal pattern auxiliary electrode with large irregularities, a metal pattern auxiliary electrode or a transparent conductive layer is formed in advance on a substrate having a flat surface, and this is applied to a desired transparent support. A method of transferring to the top, a method of flattening the opening of the metal pattern auxiliary electrode with a transparent resin, applying a transparent conductive layer containing conductive fibers thereon, and then applying pressure or pressure heat treatment to the surface side Etc. As a pressurization method, there are a nip roll pressurization in which a base film is passed between rolls and a method of pressurizing a plate with a roll. The material of the roll or plate is not particularly limited, but a metallic material is preferable in order to enhance the smoothing effect. Although the magnitude | size of a pressurization is arbitrarily possible in the range of 1 kPa to 100 MPa, Preferably it is the range of 10 kPa-10 MPa, More preferably, it is 50 kPa-5 MPa. When the pressure is less than 1 kPa, it is difficult to obtain a smoothing effect. Moreover, it is effective to heat simultaneously with pressurization, and it is preferable to heat in the range of 40 to 300 degreeC in that case. The heating time is adjusted in relation to the temperature and can be short at a high temperature and long at a low temperature. In the case of a nip roll, the heating method includes a method in which the roll is heated to a predetermined temperature in advance and a method in which heating is performed in a heating chamber such as an autoclave chamber. A method of laminating a plurality of samples of a predetermined size and heating them at a time is preferable because of high productivity.

  There is no restriction | limiting in particular in the thickness of the transparent conductive film 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 improves, so that thickness becomes thin. Therefore, it is more preferable.

  The total light transmittance in the transparent conductive film of the present invention is preferably 70% or more, and more preferably 80% or more. Moreover, as an electrical resistance value in the transparent conductive film of the present invention, from the viewpoint of functionality as a transparent conductive film, the surface resistivity is preferably 30Ω / □ or less, preferably 10Ω / □ or less, preferably 3Ω / □ or less. More preferably.

[Organic electroluminescence device]
The organic electroluminescent element in the present invention has the transparent conductive film of the present invention. The organic electroluminescent element in the present invention uses the transparent conductive film of the present invention as an anode, and the organic light emitting layer and the cathode are made of any materials and structures generally used in organic electroluminescent elements. Can do. The element configuration of the organic electroluminescence element is anode / organic light emitting layer / cathode, anode / hole transport layer / organic light emitting layer / electron transport layer / cathode, anode / hole injection layer / hole transport layer / organic light emitting layer / electron transport. Examples of various configurations such as layer / cathode, anode / hole injection layer / organic light emitting layer / electron transport layer / electron injection layer / cathode, anode / hole injection layer / organic light emitting layer / electron injection layer / cathode, etc. Can do.

  In addition, as the light emitting material or doping material that can be used in the organic light emitting layer in the present invention, anthracene, naphthalene, pyrene, tetracene, coronene, perylene, phthaloperylene, naphthaloperylene, diphenylbutadiene, tetraphenylbutadiene, coumarin, oxadiazole, bisbenzo Xazoline, bisstyryl, cyclopentadiene, quinoline metal complex, tris (8-hydroxyquinolinato) aluminum complex, tris (4-methyl-8-quinolinato) aluminum complex, tris (5-phenyl-8-quinolinato) aluminum complex, Aminoquinoline metal complex, benzoquinoline metal complex, tri- (p-terphenyl-4-yl) amine, 1-aryl-2,5-di (2-thienyl) pyrrole derivative, pyran, quinacridone Rubrene, distyrylbenzene derivatives, di still arylene derivatives, and various fluorescent dyes and rare earth metal complex, there are phosphorescent materials, but is not limited thereto. It is also preferable to include 90 to 99.5 parts by mass of a light emitting material selected from these compounds and 0.5 to 10 parts by mass of a doping material. The organic light emitting layer is prepared by a known method using the above materials and the like, and examples thereof include vapor deposition, coating, and transfer. The thickness of the organic light emitting layer is preferably 0.5 to 500 nm, particularly preferably 0.5 to 200 nm.

  The organic electroluminescent element in the present invention can be used for a self-luminous display, a liquid crystal backlight, illumination, and the like. Since the organic electroluminescent element of the present invention can emit light evenly over a large area, it is particularly preferred to be used for illumination.

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

Example 1
(Production of metal pattern auxiliary electrode film)
[Metal pattern auxiliary electrode film 1]
The following solution A was kept at 34 ° C. in a reaction vessel, and the pH was adjusted to 2.95 using nitric acid (concentration 6%) while stirring at high speed using a mixing and stirring device described in JP-A-62-2160128. It was adjusted. Subsequently, the following solution B and the following solution C were added at a constant flow rate over 8 minutes and 6 seconds using the double jet method. After completion of the addition, the pH was adjusted to 5.90 using sodium carbonate (concentration 5%), and then the following solution D and solution E were added.

(Solution A)
Alkali-treated inert gelatin (average molecular weight 100,000) 18.7g
Sodium chloride 0.31g
Solution I (below) 1.59ml
Pure water 1246ml
(Solution B)
169.9g of silver nitrate
Nitric acid (concentration 6%) 5.89ml
Finish to 317.1 ml with pure water.

(Solution C)
Alkali-treated inert gelatin (average molecular weight 100,000) 5.66 g
Sodium chloride 58.8g
13.3 g of potassium bromide
Solution I (below) 0.85ml
Solution II (below) 2.72 ml
Finish to 317.1 ml with pure water.

(Solution D)
2-Methyl-4hydroxy-1,3,3a, 7-tetraazaindene 0.56 g
112.1 ml of pure water
(Solution E)
Alkali-treated inert gelatin (average molecular weight 100,000) 3.96 g
Solution I (below) 0.40ml
128.5 ml of pure water
(Solution I)
Surfactant: 10% by weight methanol solution of polyisopropylene polyethylene oxydisuccinate sodium salt (Solution II)
10% by weight aqueous solution of rhodium hexachloride complex After the above operation is completed, desalting and water washing are performed using a flocculation method at 40 ° C. according to a conventional method. The pH was adjusted to 5.90 at 40 ° C., and finally a silver chlorobromide cubic grain emulsion containing 10 mol% of silver bromide and having an average grain size of 0.09 μm and a coefficient of variation of 10% was obtained.

(Solution F)
Alkali-treated inert gelatin (average molecular weight 100,000) 16.5g
Pure water 139.8ml
The silver halide emulsion was subjected to chemical sensitization at 40 ° C. for 80 minutes using 20 mg of sodium thiosulfate per mole of silver halide, and 4-hydroxy-6-methyl-1,3, after completion of chemical sensitization. 500 mg of 3a, 7-tetrazaindene (TAI) per 1 mol of silver halide and 150 mg of 1-phenyl-5-mercaptotetrazole per 1 mol of silver halide were added to obtain silver halide emulsion EM-1. In this silver halide emulsion EM-1, the volume ratio of silver halide grains to gelatin (silver halide grains / gelatin) was 0.625. Further, a hardening agent (H-1: tetrakis (vinylsulfonylmethyl) methane) was added at a ratio of 200 mg per 1 g of gelatin, and a surfactant (SU-2: sulfosuccinate disulfate) was applied as a coating aid. (2-ethylhexyl) .sodium) was added to adjust the surface tension. The amount of Gel applied is 0.13 g / m ² on the release surface of the releasable PET support subjected to corona discharge treatment with a thickness of 100 μm and surface roughness Ra = 1 nm. After the application, a curing treatment was performed at 50 ° C. for 24 hours.

  The film produced as described above is exposed using an ultraviolet lamp through a lattice-shaped photomask having a line width of 7 μm and an interval between lines of 206 μm, and the following developer (DEV-1) Then, development processing was performed at 25 ° C. for 60 seconds, and then fixing processing was performed at 25 ° C. for 120 seconds using the following fixing solution (FIX-1). Further, physical development was performed at 25 ° C. for 10 minutes using the following physical developer (PDEV-1), followed by washing with water and drying.

(DEV-1)
500 ml of pure water
Metol 2g
80 g of anhydrous sodium sulfite
Hydroquinone 4g
4g borax
Sodium thiosulfate 10g
Potassium bromide 0.5g
Add water to bring the total volume to 1 liter.

(FIX-1)
750 ml of pure water
Sodium thiosulfate 250g
Anhydrous sodium sulfite 15g
Glacial acetic acid 15ml
Potash alum 15g
Add water to bring the total volume to 1 liter.

(PDEV-1)
The following A liquid and B liquid are mixed immediately before a process.

(Liquid A)
400ml of pure water
Citric acid 10g
Disodium hydrogen phosphate 1g
Ammonia water (28% aqueous solution) 1.2ml
Hydroquinone 3g
(Liquid B)
10 ml of pure water
0.4 g of silver nitrate
After the physical development treatment, electrolytic copper plating treatment was performed at 25 ° C. using the following electrolytic plating solution, followed by washing with water and drying treatment. In addition, the current control in electrolytic copper plating was performed over 3 minutes, 3 minutes for 1 minute and then 12 minutes for 1A. After the completion of the plating treatment, the plate was rinsed with tap water for 10 minutes to carry out a water washing treatment, and dried using a dry air (50 ° C.) until it was in a dry state.

(Electrolytic plating solution)
Copper sulfate (pentahydrate) 200g
50g of sulfuric acid
Sodium chloride 0.1g
Add water to bring the total volume to 1000 ml.

  As described above, the metal pattern auxiliary electrode film 1 having a width of 10 μm, an interval of 200 μm, and a height of 6 μm was produced.

[Metal pattern auxiliary electrode film 2]
On one side of a highly heat-resistant polyimide film subjected to corona discharge treatment with a thickness of 125 μm and a surface roughness Ra = 1 nm, using a known electrostatic inkjet printer with an inner diameter of the tip of the nozzle of 10 μm, Ag paste ink, a width of 10 μm, A pattern having an interval of 160 μm and a height of 4 μm was applied and sintered at 250 ° C. for 15 minutes to form a metal pattern auxiliary electrode film 2.

[Metal pattern auxiliary electrode film 3]
After applying the following colloidal metal solution for spontaneous pattern formation to one side of a releasable PET film having a thickness of 100 μm and a surface roughness Ra = 1 nm subjected to corona discharge treatment at a wet film thickness of 40 μm, at 50 ° C. Dried. This was immersed in a formic acid aqueous solution and dried to form a metal pattern auxiliary electrode film 3 having a width of 5 μm, an interval of 100 μm, and a height of 2 μm.

<Metallic colloid solution>
BYK-410 (manufactured by BYK Chemie) 0.11
SPAN-80 (manufactured by Tokyo Chemical Industry) 0.11
Dichloroethane 75.63
Cyclohexanone 0.42
Silver powder (average particle size 70 nm) 3.59
BYK-348 (0.02% aqueous solution; manufactured by BYK Chemie) 19.98
ZonylFSH (DuPont) 0.08
Butver B-76 (Solutia) 0.08
(Preparation of conductive fiber dispersion)
[Conductive fiber dispersion a]
Referring to the method described in Non-Patent Document 1 (Adv. Mater. 2002, 14, 833 to 837), ethylene glycol (EG) as a reducing agent and polyvinylpyrrolidone (PVP: PVP: An average molecular weight of 1,300,000 (manufactured by Aldrich) was used, and the nucleation step and the particle growth step were separated to form particles to prepare a silver nanowire dispersion.

(Nucleation process)
While stirring 100 ml of the EG solution maintained at 160 ° C. in the reaction vessel, 2.0 ml of an EG solution of silver nitrate (silver nitrate concentration: 1.0 mol / l) was added at a constant flow rate over 1 minute. Thereafter, the silver ions were reduced while being held at 160 ° C. for 10 minutes to form silver core particles. The reaction solution exhibited a yellow color derived from surface plasmon absorption of nano-sized silver fine particles, and it was confirmed that silver ions were reduced to form silver fine particles (nuclear particles). Subsequently, 10.0 ml of PVP EG solution (PVP concentration: 3.0 × 10 ⁻¹ mol / L) was added at a constant flow rate over 10 minutes.

(Particle growth process)
The reaction liquid containing the core particles after the nucleation step 1 is maintained at 160 ° C. with stirring, 100 ml of an EG solution of silver nitrate (silver nitrate concentration: 1.0 × 10 ⁻¹ mol / l), and PVP 100 ml of EG solution (PVP concentration: 3.0 × 10 ⁻¹ mol / l) was added over 120 minutes at a constant flow rate using the double jet method. In the particle growth process, the reaction solution was sampled every 30 minutes and confirmed with an electron microscope. As a result, the core particles formed in the nucleation process grew into a wire-like form over time. The formation of new fine particles was not observed. About the silver nanowire finally obtained, the electron micrograph was image | photographed, the particle size of the major axis direction and the minor axis direction of 300 silver nanowire particle images was measured, and the arithmetic average was calculated | required. The average particle size in the minor axis direction was 100 nm, and the average length in the major axis direction was 40 μm.

(Demineralized water washing process)
After cooling the reaction solution after the particle formation step to room temperature, it was subjected to demineralized water washing treatment using an ultrafiltration membrane having a fractional molecular weight of 0.2 μm, and the solvent was replaced with ethanol. Finally, the liquid volume was concentrated to 100 ml to prepare a silver nanowire EtOH dispersion.

  The silver nanowire EtOH dispersion and a 25% methyl isobutyl ketone solution of urethane acrylate were mixed so that the concentration of the silver nanowire was 0.5% to prepare a conductive fiber dispersion a.

[Conductive fiber dispersion b]
0.5 parts of purified high-purity single-walled carbon nanotubes (manufactured by Carbon Nanotechnology Inc .; hereinafter referred to as “SWNT”) are dispersed in a methyl isobutyl ketone solution in which 7 parts of urethane acrylate is dissolved, and a conductive fiber dispersion b was produced.

[Conductive fiber dispersion c]
The conductive fiber dispersion a and the EtOH solution in which 0.5 parts of purified high-purity SWNTs were dispersed were mixed so that the ratio of silver nanowires and SWNTs was 1: 1 to prepare a conductive fiber dispersion c. .

(Preparation of transparent conductive film 101)
A conductive fiber dispersion liquid a was applied onto the metal pattern auxiliary electrode film 1 so that the basis weight of the silver nanowires was 0.25 g / m ² and dried to prepare a transfer film.

  Separately, an ultraviolet curable resin (UVPOT Medium 0, manufactured by Teikoku Ink Co., Ltd.) as an adhesive layer is applied to one side of a transparent PET support having a thickness of 100 μm to a thickness of 30 μm. Produced. The transparent support with adhesive resin and the transfer film were pressure-bonded so that the adhesive layer and the metal pattern auxiliary electrode face each other, and then the ultraviolet curable resin was cured by irradiating ultraviolet rays from the transparent support side. The releasable support was peeled off to produce a transparent conductive film 101.

(Preparation of transparent conductive films 102 and 103)
Transparent conductive films 102 and 103 were produced in the same manner as the transparent conductive film 101 except that the conductive fiber dispersion a on the metal pattern auxiliary electrode film 1 was changed to the conductive fiber dispersions b and c.

(Preparation of transparent conductive films 104 and 105)
Transparent conductive films 104 and 105 were produced in the same manner as the transparent conductive film 101 except that the metal pattern auxiliary electrode film 1 was changed to the metal pattern auxiliary electrodes 2 and 3.

(Preparation of transparent conductive film 106)
A metal pattern auxiliary electrode film 1B was produced in the same manner except that the releasable support of the metal pattern auxiliary electrode film 1 was changed to an easy adhesion processed transparent PET support.

Next, the following ultraviolet curable resin composition 1 was applied on the metal pattern auxiliary electrode, dried at 80 ° C. for 1 minute, and then irradiated with 120 mJ / cm ² of ultraviolet light from the side of the transparent PET support that had been subjected to easy adhesion processing with a high-pressure mercury lamp. Then, an ultraviolet curable resin layer was provided so that the film thickness after curing was 5 μm. Further, the uncured resin on the metal pattern auxiliary electrode was washed away with methyl ethyl ketone and dried.

<Ultraviolet curable resin layer coating composition 1>
Pentaerythritol triacrylate 100 parts by weight Dimethoxybenzophenone photoinitiator 4 parts by weight Methyl ethyl ketone 75 parts by weight Propylene glycol monomethyl ether 75 parts by weight From this, the conductive fiber dispersion a has a basis weight of silver nanowires of 0.25 g / m ² The film was applied and dried as described above, and the film was passed through a metal nip roll whose surface was heated to 110 ° C. by applying a pressure of 1 Mpa, thereby smoothing the film and producing a transparent conductive film 106.

(Preparation of transparent conductive film 107)
A dispersion liquid containing ITO nanoparticles having an average particle diameter of 30 nm and a polyester resin is applied on the metal pattern auxiliary electrode film 1 so that the dry film thickness is 300 nm, and then dried at 110 ° C. for 30 minutes for transfer. A transparent conductive film 107 was prepared in the same manner as the transparent conductive film 101 except that the film for manufacturing was prepared.

(Preparation of transparent conductive film 108)
A transparent conductive film 108 was produced in the same manner as the transparent conductive film 101 except that the conductive fiber dispersion a was applied onto the release film to produce a transfer film.

(Preparation of transparent conductive film 109)
A transparent conductive film 109 was produced in the same manner as the transparent conductive film 101 except that the metal pattern auxiliary electrode film 1 was used as a transfer film.

(Preparation of transparent conductive film 110)
A transparent conductive film 110 was produced in the same manner as the transparent conductive film 101 except that the releasable support was changed to a releasable PET film subjected to corona discharge treatment having a thickness of 100 μm and a surface roughness Ra = 6 nm. .

  With respect to the transparent conductive films 101 to 110 obtained as described above, total light transmittance, surface resistivity, surface roughness, and cracks were determined by the following methods.

[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 resistivity]
In accordance with JIS K 7194: 1994 (resistivity test method using a 4-probe method for conductive plastics), the measurement was performed using a Lorester GP (MCP-T610 type) manufactured by Mitsubishi Chemical Corporation.

[Surface roughness]
The surface was measured with an atomic force microscope (AFM) and determined by arithmetic mean roughness.

[crack]
The surface of the transparent conductive film was observed with an optical microscope, and the presence or absence of cracks was observed.

  The evaluation results are shown in Table 1.

Example 2
(Preparation of organic electroluminescence device (organic EL device))
Organic EL elements 201 to 210 were produced in the same manner as described above except that the transparent conductive films 101 to 110 produced in Example 1 were used as the first electrode.

<Formation of hole transport layer>
On the first electrode, 1.2. Coating for forming a hole transport layer in which 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD) as a hole transport material is dissolved in dichloroethane so as to be 1% by mass. The solution was applied by a spin coater and then dried at 80 ° C. for 60 minutes to form a 40 nm thick hole transport layer.

<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. % And the blue dopant material FIr (pic) are mixed so as to be 3% by mass, respectively, so that the total solid concentration of PVK and the three dopants is 1% by mass. A coating solution for forming a light emitting layer dissolved in dichloroethane was applied by 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 brightness unevenness]
Using a KEITHLEY source measure unit type 2400, a direct current voltage was applied to the organic EL element to emit light. Regarding the organic EL elements 201 to 210 that emitted light at 200 cd / m ² , each light emission unevenness was observed with a 50 × microscope.

Evaluation standard of light emission unevenness A: 90% or more of the light emitted uniformly.
○: Eighty percent or more emit light uniformly.
(Triangle | delta): 70% or more is light-emitting uniformly.
X: Less than 70% emitted light.

  The evaluation results are shown in Table 2.

  From the results of Tables 1 and 2, it can be seen that the transparent conductive film of the present invention has a low surface resistance, a high surface smoothness, and even when used as an electrode of an organic electroluminescent element, there is little unevenness in light emission luminance. .

  That is, the means of the present invention can provide a transparent conductive film that is excellent in conductivity, transparency, and flexibility, has high smoothness, and is inexpensive, and a method for producing the same.

Example 3
A solution obtained by adding 5% dimethyl sulfoxide to Baytron PH510 (manufactured by HC Starck) on the surface of the transparent conductive films 101 to 106 produced in Example 1 was applied to a dry film thickness of 30 μm. Even when the same evaluation as in Examples 1 and 2 was performed, the excellent performance of the transparent conductive film of the present invention was confirmed.

Schematic sectional view of an embodiment of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transparent support 2 Transparent conductive layer 3 Metal pattern auxiliary electrode 4 Conductive fiber

Claims (5)

A transparent conductive film having an auxiliary electrode composed of a metal pattern having an opening on a transparent support, and a transparent conductive layer containing conductive fibers, wherein the surface roughness on the opposite side of the transparent support A transparent conductive film having a thickness Ra ( _S ) of 5 nm or less. 2. The transparent conductive film according to claim 1, wherein many conductive fibers of the transparent conductive layer are present on a side far from the transparent support. The transparent conductive film according to claim 1, wherein the conductive fibers contain carbon nanotubes or metal nanowires. An organic electroluminescence device comprising the transparent conductive film according to claim 1. It is a manufacturing method of the transparent conductive film of any one of Claims 1-3, Comprising: The transparent electrode layer containing the said auxiliary electrode and a conductive fiber was laminated | stacked in this order previously on the releasable support body. Thereafter, the auxiliary electrode and the transparent conductive layer are transferred to a transparent support.

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