JPH056283B2 - - Google Patents

Description

[Detailed description of the invention]

TECHNICAL FIELD OF THE INVENTION The present invention relates to a transparent electrode, and more particularly to a transparent electrode that has excellent corrosion resistance, antioxidation properties, and mechanical strength, and can be used in applications where it is in direct contact with the outside. Technical background of the invention and its problems Transparent electrodes formed on glass or plastic (hereinafter referred to as glass) substrates are used in liquid crystal displays, electrochromic displays, plasma displays, and electroluminescent displays due to their excellent transparency. It is used as an electrode for display parts such as fluorescent display tubes, or as a transparent electrode for membrane switches and the like. In transparent electrodes used in such liquid crystal displays, etc., the transparent electrodes are formed on a substrate, but these transparent electrodes are not in direct contact with the outside world and are used inside the device. The reason why the transparent electrode must be used inside the device rather than in a place where it comes into contact with the outside world is as follows. In other words, these transparent electrodes are generally formed on a substrate such as glass by a vapor phase method such as evaporation method or sputtering method, but these transparent electrodes are easily corroded by acids or alkalis, or easily oxidized in the air. or electrical resistance depending on temperature,
This is because it changes depending on humidity and the like, and furthermore, it has a weak mechanical strength and is easily damaged, causing the electrode to break. By the way, in recent years, there has been a need to apply transparent electrodes to transparent digitizers or telewriting terminals, etc., which are being developed for the purpose of directly inputting information to computers etc. from outside the display device. The electrodes will be in direct contact with the outside world. However, conventionally known transparent electrodes have weak mechanical strength, so they easily break when they come into contact with input terminals such as input vents, and are easily corroded by acids, alkalis, or air. Due to these major problems, the transparent electrode could not be applied to the transparent digitizer or telewriting terminal. Furthermore, as described above, a vapor deposition apparatus is required to form a transparent electrode on a base material such as glass by a vapor phase method, which increases production costs.
Furthermore, the size of the substrate used is determined by the size of the vapor deposition equipment used to form the transparent electrode on the substrate, making it difficult to obtain a large-area transparent electrode. There was a problem. Purpose of the Invention The present invention aims to solve the problems associated with the prior art as described above. The purpose is to provide a transparent electrode that can be used at low cost. Summary of the Invention The transparent electrode according to the present invention has a carrier movement speed of 10 ^-8 cm ² /V·sec on a transparent insulating substrate such as glass.
An electrode film containing a specific conductive indium oxide fine powder dispersed in a photoconductive resin (hereinafter sometimes referred to as electrode binder resin) as described above, and an ultraviolet curable film provided on the film. A conductive protective film containing a specific conductive oxide fine powder dispersed in a binder resin and/or a thermosetting binder resin (hereinafter sometimes referred to as conductive protective film binder resin) was provided. Has a structure. The transparent electrode according to the present invention has excellent transparency and conductivity, as well as excellent corrosion resistance, antioxidant properties, and mechanical strength. Detailed Description of the Invention The transparent electrode according to the present invention will be described in detail. As shown in FIG. 1, the transparent electrode according to the present invention has an electrode film 2 and a conductive protective film 3 in the above order on a transparent insulating substrate 1 made of plastic or glass. explain. The insulating substrate 1 used in the present invention is made of glass or plastic, and is preferably transparent, but it may be colored or opaque depending on the case. An electrode film 2 formed on such an insulating substrate 1
is preferably transparent, and this electrode film 2
has a film thickness of 1 to 20 μm and a surface resistance of 10
~1000Ω/□, more preferably a film thickness of 2 to 20 μm, and a surface resistance of 10 to 500Ω/□. If the thickness of the electrode film 2 exceeds 20 μm, it is not preferable because the transparency deteriorates, and if the surface resistance of the electrode film 2 exceeds 1000Ω/□,
This is not preferable because the surface resistance becomes too high. Further, the conductive protective film 3 has a film thickness of 1 to 30 μm.
The thickness is preferably 2 to 30 μm in order to further improve the corrosion resistance and film strength of the conductive protective film. If the thickness of the conductive protective film is less than 1 μm, it is not preferable because the strength of the conductive protective film becomes weak.
If it exceeds 30 μm, the transparency of the conductive protective film deteriorates and the transparency of the electrode film is reduced, which is not preferable. Further, the volume resistance value of the conductive protective film itself is preferably 0.1 to 10 ⁶ Ω·cm. If the volume resistance value of the conductive protective film itself exceeds 10 ⁶ Ω·cm, it is not preferable because current will hardly flow in the thickness direction, impairing the function of the electrode and making it impossible to use it as a transparent electrode. The transparent electrode of the present invention, in which the electrode film 2 and the conductive protective film 3 are sequentially formed on the transparent insulating substrate 1, preferably has a surface resistance of 10 to 5000 Ω/□ as a whole. If it exceeds 5000Ω/□, it is not preferable because it cannot be used as a transparent electrode. The electrode film 2 according to the present invention is produced by using an electrode film paint in which (a) conductive indium oxide fine powder is dispersed in (b) an electrode binder resin.
It is formed on a transparent insulating base material 1. The conductive indium oxide fine powder used for this electrode film 2 may be indium oxide fine powder or
Indium oxide fine powder doped with one or more different elements such as Sn, F, and Cl is used. Further, the conductive protective film 3 according to the present invention is produced by using a paint for a conductive protective film in which (c) a conductive oxide fine powder is dispersed in (d) a binder resin for a conductive protective film. Then, it is formed on the electrode film 2 provided on the transparent insulating base material 1 as described above. The conductive oxide fine powder used in this conductive protective film paint is indium oxide fine powder or conductive indium oxide doped with one or more different elements such as Sn, F, and Cl. Fine powder, or conductive tin oxide fine powder in which tin oxide is doped with one or more different elements such as Sb, F, Cl, P, etc., is used. Furthermore, the conductive indium oxide fine powder and the conductive tin oxide fine powder may be mixed and used. In the present invention, the average particle diameter in the paint of the conductive indium oxide fine powder used in the electrode film and the conductive oxide fine powder used in the conductive protective film is 0.01 to 0.6 μm, preferably 0.01 to 0.5 μm. It is preferable that the particle size is in the μm range and that it contains only a small amount of coarse particles of 0.8 μm or more. The method for producing these fine powders is not particularly limited, but preferably the fine powders obtained by the method disclosed in Japanese Patent Application Laid-Open No. 62-51008 previously filed by the present applicant are preferred. Among these conductive fine powders, for example, the method for preparing conductive indium oxide fine powder and conductive tin oxide fine powder is explained by preparing an aqueous solution of an indium compound or a tin compound under a pH condition of 8 to 12. By gradually hydrolyzing the compounds therein, a sol containing colloidal particles of metal oxide, hydrous oxide, or metal hydroxide is produced, and this sol is then dried, calcined, and pulverized. As a starting material, it is water-soluble and has a pH of 8 to 12.
A hydrolyzable tin compound or indium compound is used within the range of 1. Specifically, indium compounds such as indium nitrate and indium sulfate, or tin compounds such as potassium stannate and sodium stannate can be used. . When the metal species contained in the aqueous solution of an indium compound or tin compound (hereinafter sometimes referred to as the raw material solution) is either indium or tin, the resulting fine powder is composed of indium oxide or tin oxide, respectively. However, by dissolving a small amount of a different element in the raw material liquid, a conductive fine powder doped with a different element can be obtained. For example, by dissolving a small amount of a tin compound in a raw material liquid containing an indium compound,
A conductive fine powder in which indium oxide is doped with tin can be obtained, and a small amount of tartarite (potassium antimonyl tartrate) or ammonium fluoride is dissolved in the raw material solution containing the tin compound. Accordingly, a conductive fine powder in which tin oxide is doped with antimony or fluorine can be obtained. The conductive fine powder doped with a different element can also be produced by the following method.
That is, a tin compound is used in the raw material liquid, the tin compound in the liquid is gradually hydrolyzed under the above PH conditions to generate a sol, colloidal particles are collected from this sol, and then antimony The tin compound is doped with antimony, phosphorus, fluorine, etc. by impregnating the colloidal particles with at least one aqueous solution of a compound, a phosphorus compound, or a fluorine compound, and then drying and calcining the particles. conductive fine powder can be produced. Alternatively, an aqueous solution of an indium compound is used as the raw material solution, a sol is generated in the same manner as above, and colloidal particles are collected from this sol, and then an aqueous solution of a tin compound and/or a fluorine compound is added to the colloidal particles. A conductive fine powder in which an indium compound is doped with tin and/or fluorine can be produced by impregnating the particles, then drying and firing the particles. Regardless of whether the raw material liquid is a tin compound or an indium compound, if by-product salts are generated during the sol generation process, not only will the colloidal particles be more likely to aggregate, but the final product Since the specific resistance of the conductive fine powder increases due to the presence of by-product salts, if the formation of by-product salts is expected,
It is preferable to remove by-product salts from the colloid particles before impregnating the colloid particles recovered from the sol with the metal compound aqueous solution. The concentration of the tin compound or indium compound contained in the raw material liquid can be arbitrarily selected, but
Generally, a range of 0.5 to 30% by weight is preferred. The indium compound or tin compound contained in the above raw material liquid is hydrolyzed together with a compound of a different element as a dopant when the compound of a different element coexists under conditions of pH 8 to 12 to cause a hydrolysis reaction. While doing this, always keep the pH of the reaction system between 8 and 12.
must be maintained within the range of The PH of the reaction system is
If the pH is less than 8, the particle size distribution of the resulting conductive fine powder will be broad even if the pH is close to 8, and if the PH value further decreases, metal oxides, hydrated oxides, or metal hydroxides generated by hydrolysis will be This is not preferable because it settles as a precipitate and cannot be dispersed in the liquid as colloidal particles, making it impossible to prepare a sol. on the other hand,
If the pH of the reaction system exceeds 12, although it is not impossible to prepare a sol, the alkali content cannot be sufficiently removed when washing the colloid particles filtered from the sol, resulting in The conductivity of the powder deteriorates. Therefore, when carrying out the above hydrolysis reaction, water maintained at a pH of 8 to 12,
The raw material solution is added at a feed rate that does not cause the PH of the reaction system to deviate from a predetermined range. At this time, if the raw material liquid is acidic, it is preferable to add an alkali to the reaction system, and if it is alkaline, add an acid to the reaction system at the same time as the raw material liquid. There is no particular restriction on the solid content concentration of the sol produced as a result, but in general, as the concentration increases, the particle size distribution of the colloid particles produced tends to become broader. The reaction temperature for hydrolysis is usually
The temperature can be arbitrarily selected within the range of 30 to 90°C. By preferably gradually hydrolyzing the raw material liquid under the above PH conditions, colloidal particles consisting of tin or indium metal oxides, hydrous oxides, or metal hydroxides are produced, and these particles are dispersed. A sol is prepared. In this case, if the dopant coexists in the raw material liquid, it goes without saying that colloidal particles containing the dopant can be obtained. The average particle size of colloidal particles obtained by hydrolysis is 0.05 to 0.3 μm, preferably 0.07 to 0.2 μm.
The particle size distribution is usually in the range of 0.5 to 1.5 times the average particle size, with 80% or more of all particles being in the range of 0.5 to 1.5 times the average particle size. The average particle size and particle size distribution of colloidal particles can be controlled by controlling the concentration or supply rate of the raw material liquid supplied to the hydrolysis reaction system; the lower the concentration of the raw material liquid, the sharper the viscosity distribution. . Further, the slower the feed rate of the raw material liquid, the larger the colloidal particles can grow. After preparing the sol, the sol is filtered to collect colloidal particles, the colloidal particles are washed to remove by-product salts and other substances adhering to the particles, and then dried, further calcined, and then pulverized. By this method, conductive fine powder can be obtained. The particles filtered from the sol are sintered to some extent in the firing process, and the average particle size of the fine powder becomes about 20 to 50 μm, but the specific surface area of this fine powder is 50 m ² /g or less. On the other hand, the specific surface area of fine powder produced through a conventionally known precipitation process is 70 to 100 m ² /
g. This indicates that the fine powder obtained by the present invention is composed of larger primary particles than the conventional fine powder. The fine powder obtained in this way can also be easily released from its sintered state by pulverization, and can be used as a conductive fine powder with an average particle size of 0.6 μm or less in paint by ordinary pulverization means. Obtainable. The fine powder thus obtained contains only a small amount of coarse particles of, for example, 0.8 μm or more. The conductive fine powder may be pulverized before being mixed with other components such as a binder resin, or may be pulverized after being mixed with other components such as a binder resin. The conductive fine powder can be pulverized by a conventionally known pulverization method, for example, an attritor, a sand mill, a ball mill, a three-roll machine, or the like can be used. In the present invention, the average particle size of the colloidal particles and the conductive fine powder in the paint is measured using an ultracentrifugal particle size analyzer (CAPA-500 manufactured by Horiba, Ltd.), and the solid content concentration of the sample is 0.5% by weight. Adjust to 5000rpm for colloids and 5000rpm for paints.
The measurement was performed by rotating at a speed of 2000 to 3000 rpm. Then, the particle size corresponding to 50% of the cumulative distribution of the particle size distribution was defined as the average particle size. The binder resin for electrodes (b) used in the coating for electrode films of the present invention has a carrier movement speed of
A resin having a voltage of 10 ⁻⁸ cm ² /V·sec or more is used, and specifically, photoconductive resins such as polycarbazole and diphenylaminostyrene can be used. Further, in the photoconductive resin, iodine, 2,4,7-trinitrochlorenone, tetracyanoethylene,
Resins doped with chloranil, 7,7,8,8-tetracyanoquinodimethane, nitro compounds, acid anhydrides, Lewis acids of halides, etc. may also be used. Carrier movement speed is 10 ^-8 cm ² /V・sec
If it is less than this, the resistance of the obtained electrode film 2 becomes too high and the function as an electrode film cannot be maintained, which is not preferable. In the present invention, furthermore, one or more resins selected from ultraviolet curable binder resins, thermoplastic binder resins, and thermosetting binder resins are used as binder resins having a carrier movement speed of 10 ^-8 cm ² /V·sec or more. When mixed with, it is possible to improve the coating properties of the electrode film coating material, the adhesion between the resulting electrode film and the transparent insulating substrate, and the transparency of the film. This ultraviolet curable binder resin,
Specific examples of thermoplastic binder resins and thermosetting binder resins include acrylic resins such as methacrylic resins, amino resins such as polyacetylene resins, urea resins, and melamine resins, polyamide resins, and polyimide resins. , polyamide-imide resins, polyurethane resins, polyether resins, polyester resins such as alkyd resins, chlorinated resins such as epoxy resins and chlorinated polyether resins, polyolefin resins such as polyethylene resins and polypropylene resins, Polycarbonate resin, silicone resin, polystyrene resin, ABS resin, polyamine sulfon resin, polyether sulfon resin, polyphenylene sulfon resin, etc., polysulfon resin, vinyl chloride resin, vinylidene chloride resin, vinyl acetate resin , vinyl resins such as polyvinyl alcohol resins, polyvinyl carbazole resins, and butyral resins, fluorocarbon resins, polyphenylene oxide resins, polypyrrole resins, polyphenylene resins, ultraviolet curing resins, and cellulose derivatives. . In addition, the carrier movement speed is 10 ^-8 cm ² /V・sec
The mixing ratio of the above binder resin, ultraviolet curable binder resin, thermoplastic binder resin, and thermosetting binder resin is such that the carrier movement speed of the resulting binder resin mixture is 10 ^-8
It is preferable to maintain the voltage at cm ² /V·sec or higher. If the carrier movement speed of the resulting binder resin mixture is less than 10 ⁻⁸ cm ² /V·sec, the resistance becomes too high and the function as an electrode film cannot be maintained, which is not preferable. The carrier movement speed of the binder resin means the speed at which electrons or holes move in the binder resin when an electric field is applied to the binder resin. The carrier movement speed of such binder resin is measured as follows. A binder resin having a thickness of l is provided between electrodes having a distance of l. Next, the sample is irradiated with light to excite the electrons within the sample and move the electrons to the positive electrode side. At this time, the time t ₀ when the light was irradiated and the time when the electrons reached the positive electrode
The difference from t ₁ is detected by a measuring device. Here, the carrier movement function υ(E) is expressed by the following equation. t ₁ −t ₀ =l/υ(E)=l/μE=l ² /μV Therefore μ=l ² /(t ₁ −t ₀ )V (where μ is the carrier movement speed and E is (V is the electric field and V is the voltage.) The mixing ratio of (a) conductive indium oxide fine powder and (b) electrode binder resin, or the ratio of (a) conductive indium oxide fine powder to the total weight of both. Powder is 70-95
Weight percent is preferred. (a) If the conductive indium oxide fine powder is less than 70% by weight, the conductivity of the resulting coating film will be poor, while if it exceeds 95% by weight, the adhesion between the coating film and the transparent insulating substrate will be poor, and the resulting coating film will be poor. This is not preferable because the transparency of the film deteriorates. Also used in the conductive protective film coating of the present invention.
(d) Binder resins for the conductive protective film include acrylic resins such as methacrylic resins, amino resins such as urea resins and melamine resins, polyester resins such as polyurethane resins and alkyd resins, epoxy resins, silicone resins, Vinyl resins such as polyvinyl alcohol resins, polyvinyl carbazole resins, butyral resins, fluorine resins, polyphenylene oxide resins, ultraviolet curing resins, cellulose derivatives, etc. are used. Further, mixtures of the above resins or copolymers of the above resins can be used singly or in combination of two or more. The mixing ratio of (c) conductive oxide fine powder and (d) binder resin is 40 to 95% by weight, preferably 60 to 90% by weight of (c) conductive fine powder, based on the total weight of both.
More preferably, it is 70 to 85% by weight. (c) If the conductive fine powder is less than 40% by weight, the conductivity of the resulting coating film will be poor; on the other hand, if it exceeds 95% by weight, the adhesion between the coating film and the substrate will be poor, and the transparency of the resulting coating film will be poor. It is undesirable because it causes poor performance. The electrode paint or conductive protective film paint used in the present invention has the above-mentioned components dissolved or dispersed in a solvent, and the solvent may be any solvent that can dissolve or dilute the binder resin. Can be used. Specifically, alcohols such as methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, diacetone alcohol, cyclohexanol, acetone, cyclohexanone, methyl ethyl ketone, methyl isobutyl ketone, holone, isophorone, etc. Ketones, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, carbitol, methyl carbitol, butyl carbitol, ethers such as dioxane, esters such as ethyl acetate, n-butyl acetate, petroleum such as hexane, cyclohexane, etc. Naphthas, toluene, xylene, mesitylene, benzoles such as solvent naphtha, N-methyl-2-pyrrolidone and its derivatives, etc. are used alone or in combination. Such an organic solvent is used in an amount that provides a desired film thickness and viscosity that allows the conductive paint to be applied onto the substrate. Moreover, when a water-soluble binder resin is used, water can also be used as a solvent. When manufacturing electrode paints or conductive protective film paints, in addition to the fine powder and binder resin, a surfactant is added to improve the dispersibility of the conductive fine powder and prevent particles from re-agglomerating. Alternatively, a coupling agent can be added to the conductive coating. As the surfactant, a wide range of anionic, nonionic, and cationic surfactants can be used, and as the coupling agent, silane, titanium, aluminum, zirconium, and magnesium can be used. In order to produce the electrode paint or the conductive protective film paint according to the present invention, the fine powder and binder resin as described above are added to a solvent and then uniformly dispersed in the binder resin. When kneading with the resin, the fine powder may be simultaneously pulverized as described above. The electrode paint or conductive protective film paint thus obtained can be coated using conventional coating methods such as spinner method, bar coating method, dip method, Meyer bar method, air knife method, or printing method such as gravure, screen, roll coater, etc. It is obtained by coating and then drying according to the method. Effects of the Invention The transparent electrode according to the present invention is formed on an electrode film 2 formed by applying an electrode paint made by dispersing conductive indium oxide powder and an electrode binder resin in a solvent on a transparent insulating substrate 1. The conductive protective film 3 is formed by applying a conductive protective film paint made by dispersing conductive oxide powder and conductive protective film binder resin in a solvent, so it is corrosion resistant against acids and alkalis. It has good properties and does not oxidize even when left in the air, so there is no change in electrical resistance over time, and electrical resistance is not affected by changes in temperature and humidity. Furthermore, since the transparent electrode of the present invention has extremely excellent mechanical strength, it can be used for the electrode input surface of a transparent digitizer for direct writing with an input pen, and for the transparent pad for drawing input of a telewriting terminal.
Furthermore, the electrode film and conductive protective film related to the transparent electrode of the present invention can be formed by a coating method, so they are inexpensive and can be continuously produced. The present invention will be explained below using Examples, but the present invention is not limited to these Examples. Comparative Example 1 After molding indium oxide powder containing 5% by weight tin oxide powder into a tablet shape, it was placed on a glass plate using a 2kw electron gun at a substrate temperature of 400°C and an oxygen partial pressure of 3×10 ^-4 Torr. Then, an indium oxide film containing tin oxide was deposited at a deposition rate of 3 Å/sec to obtain a transparent electrode. The film thickness was 1500 Å. Example 1 Conductive indium oxide fine powder doped with fluorine (manufactured by Catalysts & Chemicals, trade name: ELCOM TL-130)
150 g and 37.5 g of polyvinyl carbazole as an ultraviolet curing resin (manufactured by Anan Kogyo Co., Ltd., trade name Tubicol, carrier movement speed: 10 ^-6 cm ² /V sec) were added to 200 g of cyclohexanone, mixed, and mixed with a sand mill for 2 hours. An electrode coating material was prepared by time-pulverizing. The obtained paint was applied to a transparent acrylic plate using a spinner at 300 rpm for 10 seconds, and then ultraviolet rays were irradiated to form an electrode film with a thickness of 3 μm.
I got (a). Next, instead of polyvinylcarbazole, ultraviolet curing resin (manufactured by Daihachi Kagaku, product name DH-
700) A conductive protective film paint was prepared in the same manner as the electrode paint except that 500 g of n-butyl acetate was used instead of cyclohexanone, and a film thickness of 3 μm was prepared under the same conditions as the electrode film. The conductive protective film (b) was laminated on the electrode film (a) to obtain a transparent electrode. Example 2 Except for using a mixture of 2.0 g of polyester (manufactured by Toyobo Co., Ltd., trade name: Vylon) and 35.5 g of polyvinylcarbazole as the binder resin.
An electrode coating material was obtained under the same conditions as in Example 1. Apply the obtained paint to PET film using a spanner at 300 rpm.
Apply for 10 seconds and cure at 120℃ for 30 minutes to obtain a film thickness of 5μ.
An electrode film (a) of m was obtained. Next, as a conductive oxide, 50 g of conductive indium oxide fine powder doped with fluorine (manufactured by Catalysts & Chemicals Industry Co., Ltd., trade name: ELCOM)
TL-130) and conductive tin oxide fine powder doped with antimony (manufactured by Catalysts & Chemicals Industries, product name: ELCOM)
A conductive protective film paint was prepared in the same manner as the electrode paint except that 100 g of TL-30) was mixed, and a conductive protective film (b) with a thickness of 3 μm was prepared under the same conditions as Example 1.
was laminated on the electrode film (a) to obtain a transparent electrode. Example 3 Example 3 except that 30 g of polyvinyl carbazole (manufactured by Anan Kogyo Co., Ltd., trade name Tubicol) and 7.5 g of ultraviolet curing resin (manufactured by Daihachi Kagaku Co., Ltd., trade name DH-700) were mixed and used as the binder resin for the electrode. An electrode film (a) having a thickness of 3 μm was obtained under the same conditions as in Example 1. Next, 150 g of conductive tin oxide fine powder doped with antimony (product name: ELCOM TL-30, manufactured by Catalyst Kasei Kogyo Co., Ltd.)
and silicone resin (manufactured by Toray Silicone, SR-
2410) was added to 500 g of mesitylene, mixed, and ground in a sand mill for 2 hours to prepare a coating material for a conductive protective film. The obtained paint was applied to the electrode film (a) formed as described above using a spinner for 300 rpm.
Apply at pm for 10 seconds, dry at 120℃ for 10 minutes, and dry at 190℃.
Heat cures in 2 hours to form a conductive protective film with a thickness of 5 μm.
(b) was laminated on the electrode film (a) to obtain a transparent electrode. In addition, the average particle diameter of the conductive fine powder in each paint of Examples 1 to 3 is as follows. Paint for Electrode Paint for Conductive Protective Film Example 1 0.25 μm 0.30 μm 2 0.18 μm 0.35 μm 3 0.21 μm 0.47 μm The transparent electrodes obtained in the Examples and Reference Examples above were evaluated as follows. Transparency: total light transmittance (Tt) and haze,
It was measured using a haze computer (manufactured by Suga Test Instruments). Conductivity: Surface resistance (Rs) of electrode cell (YHP
(manufactured by). Film strength: The following evaluation was performed. (1) Measured by JISD0202-71 pencil hardness test. (2) According to JISH8682-80 sand drop abrasion test
400g of sand was dropped in 2 minutes and the haze and surface resistance of the worn surface before and after the test were measured. Acid resistance: After being immersed in a 50% by weight acetic acid aqueous solution at room temperature for 1 hour, it was taken out, thoroughly washed with water, dried, and peeling of the film was observed. Alkali resistance: After being immersed in a 15% by weight aqueous ammonia solution at room temperature for 1 hour, it was taken out, thoroughly washed with water, dried, and peeling of the film was observed. The results are shown in Table 1.

【table】

【table】 [Brief explanation of the drawing]

FIG. 1 is a sectional view of a transparent electrode according to the present invention. 1...Transparent insulating substrate, 2...Transparent electrode film, 3...
...Transparent conductive protective film.

Claims (1)

[Claims] 1. On a transparent insulating substrate, a carrier moving speed is
10 ^-3 cm ² /V・sec or more in the photoconductive resin,
An electrode film with a thickness of 1 to 20 μm in which 70 to 95% by weight of conductive indium oxide fine powder is dispersed, and a conductive oxide fine powder in an ultraviolet curable binder resin and/or a thermosetting binder resin. 40～
A transparent electrode characterized in that a conductive protective film having a thickness of 1 to 30 μm formed by dispersing 95% by weight is sequentially laminated. 2 Conductive oxide fine powder is indium oxide with Sn,
Conductive indium oxide fine powder with an average particle size of 0.01 to 0.6 μm doped with one or more F and Cl,
and (or) 1 Sb, F, Cl, P in tin oxide
Doped with a seed or two or more types, average particle size 0.01~
The transparent electrode according to claim 1, characterized in that it is a conductive tin oxide fine powder of 0.6 μm.