JPH1131417A - Transparent conductive film and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve anti-static effect, electromagnetic shielding effect, salt water resistance and scratch resistance by coating a display surface with the coating, which includes platinum group metal fine grains having a specified mean grain diameter, and after drying it, burning it at a temperature within a specified range so as to form a transparent conductive layer, in which a part of the platinum group metal is converted to the platinum group metal oxide. SOLUTION: Ruthenium agveous sol, which includes fine grains of platinum group metal having a mean particle size of 50 nm or less, and isopropyl alcohol and ethyl alcohol are mixed. This mixture liquid is dispersed for adjustment by an ultrasonic dispersing device so as to obtain the transparent conductive film coating, by applying this coating on a display surface of a cathode-ray tube, and dried, and thereafter, the transparent thin film coating is further coated. This cathode-ray tube is put in a dryer, and burned at 300-1000 deg.C so as to expose a part or all of the platinum group metal, and a low-reflection transparent conductive film is thereby formed. High conductivity is thereby obtained, and charge preventing effect and electromagnetic shielding effect are improved, and transparency and durability are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is particularly useful for a display surface of a cathode ray tube or a plasma display, etc., and has a transparent and excellent antistatic effect and electromagnetic wave shielding effect, a large film strength, salt water resistance and oxidation resistance. TECHNICAL FIELD The present invention relates to a transparent conductive film having good transparency and durability such as ultraviolet light resistance, and having a natural hue of a transmitted image and good visibility, and a display device having the transparent conductive film formed on a display surface.

[0002]

2. Description of the Related Art At present, a cathode ray tube used as a TV cathode ray tube or a computer display projects characters and images on a display surface by projecting an electron beam on a phosphor screen emitting red, green and blue light. Therefore, there is a fear that dust adheres to the display surface due to static electricity generated on the display surface to lower visibility, and that the environment is affected by radiating electromagnetic waves. Recently, it has been pointed out that a plasma display, which is being applied to a wall-mounted television or the like, may generate static electricity or emit electromagnetic waves.

[0003] In order to solve the problems of generation of static electricity and radiation of electromagnetic waves, conventionally, a transparent metal thin film is formed on a display surface of a display device by a sputtering method or a vapor deposition method, or fine particles such as silver and gold are used. Is applied to a display surface by dispersing the compound in a liquid, and a transparent conductive film is formed to achieve antistatic and / or electromagnetic wave shielding. In addition, when these thin films are formed on the display surface, interface reflection occurs and visibility is reduced. To prevent this, the upper and / or lower layers of the transparent conductive film have different refractive indices. Lamination of a transparent thin film is also performed.

For example, Japanese Patent Application Laid-Open No. 8-77832 discloses that
As a transparent conductive film excellent in an electromagnetic wave shielding effect and an antireflection effect, a transparent metal thin film made of a metal fine particle containing at least silver having an average particle diameter of 2 to 200 nm and a transparent film having a refractive index different from that of the transparent metal thin film have been proposed. I have.

[0005]

According to these methods, although antistatic and electromagnetic wave shielding effects can be expected, when silver is used as a metal, absorption at a specific wavelength of transmitted light depends on its light transmission spectrum. The problem is that the conductive film is colored and the hue of the transmitted image looks unnatural, the film is soft and scratches easily occur, and silver is deteriorated when exposed to salt water, and the surface of the conductive film is deteriorated. Since the resistance value is increased and the electromagnetic wave shielding effect is reduced, there has been a problem that durability is poor especially in a place exposed to salt fog, such as a beach, so that it has been difficult to put it to practical use. The present invention has been made in order to solve the above-described problems, and accordingly, has as its object a transparent and excellent antistatic effect and an electromagnetic wave shielding effect, and has a large film strength and is represented by salt water resistance. Another object of the present invention is to provide a transparent conductive film which has good durability, has a natural hue of a transmitted image, and has good visibility, and a display device having the transparent conductive film formed on a display surface.

[0006]

According to the present invention, in order to solve the above-mentioned problems, the present invention is characterized in that the average particle size is 50 nm.
Apply a paint containing at least the following platinum group metal fine particles,
After drying, a transparent conductive film having a transparent conductive layer formed by baking at a firing temperature in the range of 300 ° C. to 1000 ° C., wherein at least a part of the platinum group metal is converted to a platinum group metal oxide is provided. I do. In the above, the transparent conductive layer is made of a platinum group metal and a platinum group metal oxide in total of 10
Preferably, it is contained in an amount of at least% by weight. Preferably, the platinum group metal is at least ruthenium.
Preferably, the platinum group metal oxide is at least ruthenium oxide. In the above, it is preferable that one or more transparent thin films having a refractive index different from the refractive index of the transparent conductive layer are provided in the upper layer and / or the lower layer of the transparent conductive layer. It is preferable that a transparent thin film having irregularities is provided on the outermost layer of the transparent conductive film. It is preferable that at least one layer of the transparent conductive film contains a coloring material. The present invention also provides a display device according to claim 8, wherein any one of the transparent conductive films is formed on a display surface.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below. The present inventors have conducted intensive research on a transparent conductive film that can be used on the display surface of a display device, is transparent, has an excellent antistatic effect and an electromagnetic wave shielding effect, and has excellent durability. Ruthenium having an average particle size of 50 nm or less,
The above object is achieved by applying a paint containing fine particles of a platinum group metal composed of palladium, platinum, rhodium, iridium or osmium to a substrate, drying and baking at a firing temperature in the range of 300 ° C to 1000 ° C. The inventors have found what can be achieved, and have reached the present invention.

[0008] A paint containing the platinum group metal fine particles having an average particle size of 50 nm or less is applied on a substrate, dried and then dried at 300 ° C.
When the film is formed by baking at a temperature of up to 1000 ° C., the total surface area of the fine particles becomes sufficiently large because the particle size of the metal fine particles is small, and a part or all of the platinum group metal is converted to an oxide at the above-mentioned baking temperature. . The platinum group metal oxide has not only higher chemical stability typified by salt water resistance than the platinum group metal, but also does not impair the conductivity of the transparent conductive film even if the oxide is generated. If the baking temperature is lower than 300 ° C., the formation of the platinum group metal oxide is insufficient,
If the temperature exceeds 0 ° C., troubles such as damage to the base material and deterioration of the film components occur.

At the same time as the formation of the oxide, in the transparent conductive film obtained by baking in the above-mentioned temperature range, at least a part of the metal fine particles fuse with each other to form an at least partially continuous metal thin film and / or metal oxide. An object thin film is formed. For this reason, in the transparent conductive film of the present invention,
A much higher conductivity than that obtained by simply contacting the metal fine particles is obtained, and as a result, not only the antistatic effect and the electromagnetic wave shielding effect are excellent, but also the transparent conductive film having high transparency and durability. Is obtained. When the average particle diameter of the platinum group metal fine particles exceeds 50 nm, formation of oxides and fusion of the particles become insufficient, and transparency is lost when light absorption is increased and sufficient conductivity is obtained. Practicality decreases.

The transparent conductive film preferably contains a platinum group metal and a platinum group metal oxide in a total amount of 10% by weight or more. In general, the conductive performance of a transparent conductive film required to exhibit an electromagnetic wave shielding effect in addition to an antistatic function is represented by the following equation 1. S = 50 + 10log (1 / ρf) + 1.7t√ (f / ρ) Formula 1 In the formula, S (dB): electromagnetic wave shielding effect, ρ (Ω-cm): Volume resistivity of the conductive film, f (MHz) Electromagnetic wave frequency, and t (cm); thickness of conductive film. Here, the thickness t is 1 μm from the viewpoint of securing transparency.
(1 × 10 ⁻⁴ cm) or less, the electromagnetic wave shielding effect S can be approximately expressed by the following expression 2 if the term including the film thickness t is ignored in the expression 1. S = 50 + 10log (1 / ρf) Equation 2

Here, as the value of S (dB) increases, the electromagnetic wave shielding effect increases. Generally, the electromagnetic wave shielding effect is S>
If it is 30 dB, it is considered to be effective, and if S> 60 dB, it is considered to be excellent. In addition, since the frequency of the electromagnetic wave to be regulated is generally in the range of 10 kHz to 1000 MHz, the conductivity of the transparent conductive film needs to have a volume resistivity (ρ) of 10 ³ Ω-cm or less. That is, the lower the volume specific resistance value (ρ) of the transparent conductive film, the more effectively electromagnetic waves of a wider range of frequencies can be shielded. In order to satisfy this condition, it is necessary that the transparent conductive film contains the platinum group metal and the platinum group metal oxide in a total amount of 10% by weight or more. If the content is less than 10% by weight, the conductivity is reduced, and it is difficult to obtain a substantial electromagnetic wave shielding effect.

After satisfying the above conditions, the thickness of the transparent conductive film should be 200 in consideration of transparency and antireflection properties.
nm or less is preferable. The obtained transparent conductive film may be a smooth film or a film having an uneven network structure.

The platinum group metal used in the transparent conductive film of the present invention may be any one or more of ruthenium, palladium, platinum, rhodium, iridium and osmium, with ruthenium being particularly preferred. Among the platinum group metals, ruthenium is relatively inexpensive, has high conductivity, high chemical stability, and easily fuses metal particles at the time of film formation, thus further improving conductivity while maintaining high transparency. be able to. In addition, ruthenium
Readily converted to RuO ₂ by baking in the range of 300 ° C. to 1000 ° C.. RuO ₂ has extremely high chemical stability and electrical conductivity typified by salt water resistance, and does not have a light absorption peak of a specific wavelength in the visible light region of 400 nm to 700 nm even in hue. It has the advantage of not coloring. Further, the transparent conductive film converted into at least ruthenium oxide has an optimized refractive index, and is preferable in terms of antireflection performance. The state of ruthenium and ruthenium oxide present in the transparent conductive film may be in the form of fine particles, or may be in a state where the particles are fused with each other and are at least partially continuous.

The transparent conductive film of the present invention may contain, if necessary, other components, in addition to the platinum group metal and the platinum group metal oxide, for the purpose of further improving film strength, conductivity, transparency and the like.
For example, fine particles of oxides or composite oxides such as silicon, aluminum, zirconium, cerium, titanium, yttrium, zinc, magnesium, indium, tin, antimony, and gallium; metal fine particles such as silver, gold, copper, and nickel; and silicon. , A metal alkoxide hydrolyzate such as titanium or zirconium, or an inorganic binder component such as a silicone monomer or silicone oligomer.

The above-mentioned paint containing at least the platinum group metal fine particles is preferably obtained by mixing the above-mentioned aqueous sol of the platinum group metal and, if necessary, the aqueous sol of other components together with an alcohol. It can be easily prepared by dispersing using a method such as In order to apply this paint on a substrate, any of ordinary thin film application techniques such as spin coating, roll coating, spraying, bar coating, dipping, meniscus coating, and gravure printing can be used. is there. Of these, spin coating is a particularly preferred coating method because a thin film having a uniform thickness can be formed in a short time. After application, the coating film is dried,
By baking at a firing temperature in the range of up to 1000 ° C., a transparent conductive film in which at least a part of the platinum group metal is converted to a platinum group metal oxide can be formed on the surface of the substrate.

In the transparent conductive film of the present invention, the transparent conductive film is used as a transparent conductive layer, and at least one transparent thin film having a refractive index different from the refractive index of the transparent conductive layer is formed on the upper and / or lower layers. Preferably, it is provided. Thus, external light reflection at the interface of the transparent conductive film can be removed or reduced.

This transparent thin film is expected to not only prevent the interface reflection in the multilayer thin film but also protect the surface from external force when used for the display surface of a display device.
It is preferable to provide a transparent thin film having practically sufficient strength on the transparent conductive layer.

Preferred materials for the transparent thin film include silicon,
An oxide, a complex oxide, or a nitride of aluminum, zirconium, cerium, titanium, yttrium, zinc, magnesium, indium, tin, antimony, gallium, or the like can be given. In particular, the following formula: M (OR) _m R _n (where M is Si, Ti or Zr, and R is C _1-
An alkyl group of C _4, m is an integer from 1 to 4, and n is formed from 4-m a is) a compound represented by, or one or more of a mixture of a partial hydrolyzate thereof Transparent thin films are preferred. More specifically, as a material capable of forming a transparent thin film of SiO ₂ having a high surface hardness and a relatively low refractive index, tetraethoxysilane (Si (O
C ₂ H ₅ ) ₄ ) is suitably used from the viewpoints of thin film forming property, transparency, bonding property with the transparent conductive layer, film strength and antireflection performance.

The transparent thin film is formed by a method in which a coating solution containing the above-mentioned components (a coating material for a transparent thin film) is uniformly applied to a base material to form a film, similarly to the method used for forming the transparent conductive film. be able to. For coating, any of ordinary thin film coating techniques such as spin coating, roll coating, spraying, bar coating, dipping, meniscus coating, and gravure printing can be used. Of these, spin coating is a particularly preferred coating method because a thin film having a uniform thickness can be formed in a short time. After coating, the coating film is dried and baked to obtain a transparent thin film.

In general, the antireflection ability of an interface in a multilayer thin film is determined by the refractive index and thickness of the thin film and the number of laminated thin films. By appropriately designing the thickness of the film and the transparent thin film, an effective antireflection effect can be obtained. In a multilayer film having antireflection ability, when the wavelength of reflected light to be prevented is λ, if the antireflection film has a two-layer structure, the high refractive index layer and the low refractive index layer are respectively λ from the substrate side. /
By setting the optical film thickness to 4, λ / 4, or λ / 2, λ / 4, reflection can be effectively prevented. In the case of a three-layered antireflection film, λ / 4, λ /
An optical film thickness of 2, λ / 4 is effective.

In particular, considering the ease of manufacture and economy, an SiO ₂ film (refractive index: 1.46) having a relatively low refractive index and having a hard coat property is formed on the upper layer of the transparent conductive layer at λ / 4. It is preferable that the film is formed to have a film thickness.

In the transparent conductive film of the present invention comprising two or more layers including a transparent conductive layer, the baking of the transparent conductive layer and the transparent thin film may be performed sequentially or simultaneously. For example, a paint for a transparent conductive film is applied to the display surface of a display device, a paint for a transparent thin film is applied thereon, and after drying, 30
The transparent conductive layer and the transparent thin film may be simultaneously formed by baking at a temperature of 0 ° C. to 1000 ° C. to form a low-reflection transparent conductive film.

It is preferable to provide a transparent thin film having irregularities on the outermost layer of the transparent conductive film. The transparent thin film having the irregularities scatters light reflected on the surface of the transparent conductive film, and has an effect of giving excellent antiglare properties to the display surface.

At least one of the transparent conductive films of the present invention
The layer may contain a coloring material. This coloring material is used for improving the contrast of a transmitted image and adjusting the color of transmitted light and reflected light. As this coloring material,
For example, monoazo pigment, quinacridone, iron oxide yellow, disazo pigment, phthalocyanine green, phthalocyanine blue, cyanine blue,
Flavanthrone yellow, dianthraquinolyl red, indanthrone blue, thioindigo bordeaux, perinone orange, perylene scarlet, perylene red 17
8, perylene maroon, dioxazine violet, isoindoline yellow, nickel nitroso yellow, madder lake, copper azomethine yellow, aniline black, alkali blue, zinc white, titanium oxide, red iron oxide, chrome oxide,
Iron black, titanium yellow, cobalt blue, cerulean blue, cobalt green, alumina white, viridian, cadmium yellow, cadmium red, vermilion, lithopone, graphite, molybdate orange, zinc chromate, calcium sulfate, barium sulfate, calcium carbonate, lead Organic and inorganic pigments such as white, ultramarine, manganese violet, cobalt violet, emerald green, navy blue, and carbon black, as well as azo dyes, anthraquinone dyes, indigoid dyes, phthalocyanine dyes, carbonium dyes, quinone imine dyes, methine dyes, quinoline dyes, and nitro dyes Dyes such as dyes, nitroso dyes, benzoquinone dyes, naphthoquinone dyes, naphthalimide dyes and perinone dyes can be mentioned. These coloring materials can be used alone or in combination of two or more.

The type and amount of the coloring material to be used should be appropriately selected according to the optical film characteristics of the corresponding transparent conductive film. The absorbance A of the transparent thin film is generally represented by the following equation. A = log ₁₀ (I ₀ / I) = εCD where I _{0 is} incident light, I is transmitted light, C is color density, D is light distance, and ε is molar extinction coefficient.

In the transparent conductive film of the present invention, a coloring material having a molar extinction coefficient ε> 10 is generally used. The amount of the coloring material varies depending on the molar extinction coefficient of the coloring material used. Generally, the absorbance A of the laminated film and the single-layer film containing the coloring material is in the range of 0.0004 to 3 abs. Preferably, the amount is such that If these conditions are not satisfied, the transparency and / or the antireflection effect will decrease. When the coloring material is blended with the transparent conductive layer, the blending amount is 20% by weight or less, particularly 10
% By weight or less. If it exceeds 10% by weight, a decrease in conductivity is observed.
This will hinder the electromagnetic wave shielding effect.

In the display device of the present invention, any one of the transparent conductive films described above is formed on a display surface. This display device prevents the charging of the display surface, so that dust and the like do not adhere to the image display surface, shields electromagnetic waves, prevents various types of electromagnetic wave interference, and is excellent in light transmissivity. It is bright, the hue of the transmitted image is natural, the film thickness is uniform, the appearance of the display surface is good, the scratch resistance is good, and the salt water resistance is high, so it is suitable for environments exposed to salt fog. Even high durability. If the transparent thin film and / or the transparent thin film having irregularities are formed in addition to the transparent conductive layer, an antireflection effect and / or an antiglare effect for external light can be obtained.

[0028]

EXAMPLES The present invention will now be described specifically with reference to examples, but the present invention is not limited to these examples. The following were prepared as stock solutions common to Examples and Comparative Examples. (Ruthenium aqueous sol) An aqueous solution containing 0.15 mmol / l ruthenium chloride and a 0.024 mmol / l aqueous sodium borohydride solution were mixed, and the obtained colloidal dispersion was concentrated to 0.198 mmol / l. An aqueous sol containing mol / l of ruthenium fine particles was obtained. The average particle size of the ruthenium fine particles was 20 nm. (Silver aqueous sol) sodium citrate dihydrate (14
g) and an aqueous solution (6 g) in which ferrous sulfate (7.5 g) is dissolved.
0 g) was kept at 5 ° C., and silver nitrate (2.5 g) was added thereto.
An aqueous solution (25 g) in which g) was dissolved was added to obtain a red-brown silver sol. The silver sol was washed with water by centrifugation to remove impurity ions, and then added with pure water to obtain 0.185 mol / l.
An aqueous sol containing silver fine particles was obtained. The average particle size of the silver fine particles was 10 nm. (Transparent thin film paint A) Tetraethoxysilane (0.8 g)
And 0.1 N hydrochloric acid (0.8 g) and ethyl alcohol (9
8.4 g) to obtain a uniform solution.

(Example 1) Preparation of a transparent conductive film paint : Ruthenium aqueous sol 40 g Isopropyl alcohol 10 g Ethyl alcohol 50 g The above components were mixed, and the resulting mixture was mixed with an ultrasonic dispersing machine (Sonifire manufactured by BRANSON ULTRASONICS). 45
0 ") to prepare a transparent conductive film paint.

Film formation : The above-mentioned transparent conductive film paint is applied to the display surface of a cathode ray tube using a spin coater, and after drying, the above-mentioned transparent thin film paint A is applied to the application surface similarly using a spin coater. , Put this CRT in the dryer,
The cathode ray tube of Example 1 having an anti-reflection and high conductive film was formed by baking at 450 ° C. for 1 hour to form a low-reflection transparent conductive film.

(Example 2) Preparation of transparent conductive film paint : Ruthenium aqueous sol 40 g isopropyl alcohol 10 g ethyl alcohol 50 g The above components were mixed and treated in the same manner as in Example 1 to prepare a transparent conductive film paint.

Film formation : A cathode ray tube of Example 2 having an anti-reflection and high conductive film was prepared by using the above transparent conductive film paint and treating it in the same manner as in Example 1 except that the baking temperature was 600 ° C. did.

(Comparative Example 1)Preparation of transparent conductive film paint : Aqueous ruthenium sol 40 g isopropyl alcohol 10 g ethyl alcohol 50 g
An electrocoat was prepared. Film formation : Using the above transparent conductive paint, baking temperature of 15
Except that the temperature was set to 0 ° C., the same treatment as in Example 1 was performed to prevent reflection,
A cathode ray tube of Comparative Example 1 having a high conductive film was prepared.

(Comparative Example 2)Preparation of transparent conductive film paint : Aqueous silver sol 40 g isopropyl alcohol 10 g ethyl alcohol 50 g
An electrocoat was prepared. Film formation : Using the above transparent conductive film paint, as in Comparative Example 1.
Cathode ray of Comparative Example 2 having anti-reflection and high conductive film by processing
A tube was created.

(Evaluation Measurement) The performance of the low-reflection transparent conductive film formed on the cathode ray tube was measured by the following apparatus or method.
The appearance was visually evaluated. X-ray diffraction analysis: Philips "PW1710" Surface resistance: Mitsubishi Yuka "Loresta AP" (4-terminal method) Electromagnetic shielding: Calculated by the above formula 1 based on 0.5 MHz Salt water: 3 days after salt water immersion 0.5 MHz electromagnetic wave shielding property Scratch test: Under a load of 1 kg, the film surface was rubbed with a metal part at the tip of a mechanical pencil, and the degree of scratching was visually evaluated. ○: no scratch △: slightly scratched ×: scratched Transmittance: “Automatic Haze Meter H” manufactured by Tokyo Denshoku
III DP "Haze:" Automatic Haze meter HII manufactured by Tokyo Denshoku Co., Ltd. "
IDP ”Transmittance difference: The difference between the maximum transmittance and the minimum transmittance in the visible light region was determined using a“ U-3500 ”type self-recording spectrophotometer manufactured by Hitachi, Ltd. (The smaller the maximum-minimum transmittance difference in the visible light region, the flatter the transmittance and the sharper the hue of the transmitted image. Particularly, when the difference is 10% or less, the color of the transmitted image approaches black, and the higher the sharpness. Luminous reflectance: "MODEL C-11" manufactured by EG & G GAMMASCIENTIFIC Inc. Reflection color: "CR-300" manufactured by Minolta Camera (CIE colorimetric system, white in CIE chromaticity diagram Point (x =
0.3137, y = 0.3198), and Δ (Δx ² + Δy ² ) using Δx and Δy. Thus, the closer the value of √ (Δx ² + Δy ² ) is to “0”, the whiter the reflection color becomes, that is, the closer to the natural light that is easy on the eyes. ) Visibility: Comprehensive evaluation including low reflection performance, reflection color, and transmission color ○: good ○ △; somewhat good △: acceptable △ ×; somewhat poor ×: poor Among the above evaluation tests, the physicochemical test results are shown. Table 1 shows the optical test results.

[0036]

[Table 1]

[Table 2]

From the results shown in Table 1, the cathode ray tubes of Examples 1 and 2 which were coated with a coating material containing ruthenium microparticles according to the present invention and baked at 450 ° C. or 600 ° C. were analyzed by X-ray diffraction. The presence of ruthenium oxide was confirmed in the film, and the presence of ruthenium oxide was not recognized in Comparative Example 1 in which the firing temperature was 150 ° C. Comparing Example 1 and Example 2 with Comparative Example 1, it can be seen that the surface resistance is not much different from the physicochemical characteristics (Table 1), and that the electromagnetic wave shielding property, salt water resistance and scratch resistance are greatly improved. . In the optical characteristics (Table 2), the luminous reflectance was reduced, the visibility was excellent, and the reflected color was close to the white point, and the transmitted image was improved so as to look natural. As a whole of these optical characteristics, the visibility evaluation of Examples 1 and 2 was clearly superior to Comparative Example 1. In Comparative Example 2, silver was used as the conductive material. However, not only the salt water resistance was poor and the durability was poor, but also the luminous reflectance was large and the reflection color was largely biased.

[0038]

The transparent conductive film of the present invention has an average particle size of 50.
After coating and drying a coating containing at least platinum group metal fine particles of not more than nm, the coating is formed by baking at a firing temperature in the range of 300 ° C. to 1000 ° C., and at least a part of the platinum group metal is converted to a platinum group metal oxide. Since it has a transparent conductive layer formed by inversion, it has an excellent antistatic effect and an electromagnetic wave shielding effect, and has high salt water resistance and scratch resistance.
Further, the display device on which the transparent conductive film is formed has high transparency of the display surface, and the hue of the transmitted image is natural and clear. If the transparent conductive layer contains at least ruthenium, it is easily converted to RuO ₂ at the baking temperature, and while being relatively inexpensive, salt water resistance, chemical stability, and scratch resistance are further improved. Also, there is an advantage that the transmitted image is more natural on the hue surface. An upper layer of the transparent conductive layer and / or
Alternatively, when at least one transparent thin film having a refractive index different from the refractive index of the transparent conductive layer is provided as a lower layer, a transparent conductive film having low reflection can be obtained. In the display device of the present invention, since the transparent conductive film is formed on a display surface,
It has excellent antistatic effect and electromagnetic wave shielding effect, has good salt water resistance, is durable, has high scratch resistance, has high transparency of the display surface, and the hue of the transmitted image is natural and clear, A highly practical display device is obtained.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G09F 9/00 307 G09F 9/00 307Z H01B 1/08 H01B 1/08 H01J 29/88 H01J 29/88

Claims (8)

[Claims] After coating and drying a paint containing at least a platinum group metal fine particle having an average particle size of 50 nm or less, the paint is dried.
A transparent conductive film having a transparent conductive layer formed by baking at a firing temperature in a range of from about 1000C to about 1000C, wherein at least a part of the platinum group metal is converted to a platinum group metal oxide. 2. The transparent conductive film according to claim 1, wherein the transparent conductive layer contains a platinum group metal and a platinum group metal oxide in a total amount of 10% by weight or more. 3. The transparent conductive film according to claim 1, wherein said platinum group metal is at least ruthenium. 4. The transparent conductive film according to claim 1, wherein said platinum group metal oxide is at least ruthenium oxide. 5. The transparent conductive layer according to claim 1, wherein one or more transparent thin films having a refractive index different from the refractive index of the transparent conductive layer are provided on the upper and / or lower layers of the transparent conductive layer. Transparent conductive film. 6. The transparent conductive film according to claim 1, wherein a transparent thin film having irregularities is provided on an outermost layer of the transparent conductive film. 7. The transparent conductive film according to claim 1, wherein at least one layer of the transparent conductive film contains a coloring material. 8. A display device, wherein the transparent conductive film according to claim 1 is formed on a display surface.