JP3403578B2 - Antireflection colored transparent conductive film and cathode ray tube - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antireflection colored transparent conductive film and a cathode ray tube, and is particularly useful for an image display surface such as a cathode ray tube face panel, which has an excellent antistatic effect, electromagnetic wave shielding effect and antireflection effect. The present invention relates to an antireflection colored transparent conductive film having an effect and having an optimized hue and contrast of a transmitted image, and a cathode ray tube using the same for a face panel.

[0002]

2. Description of the Related Art Generally, a transparent material having a high dielectric constant, such as glass or plastic, is easily charged with static electricity and easily transmits electromagnetic waves. For this reason, a transparent conductive film is attached to a face panel of a cathode ray tube used for a TV Braun tube or a computer display for the purpose of preventing static electricity and / or shielding electromagnetic waves. Further, in a liquid crystal display plate, an electroluminescence display plate, and the like, a transparent conductive film serving as an electrode is formed inside a transparent plate material.

A conventional transparent conductive film is formed by forming a transparent conductive oxide such as indium oxide on a face panel by a sputtering method, a vapor deposition method or the like, and sticking this on the display surface of a cathode ray tube. , A dispersion liquid of antimony-doped tin oxide and a silica sol-based binder is applied to the front surface of the face panel. Also, a transparent conductive film in which at least one transparent antireflection layer is laminated on the upper layer and / or the lower layer of the transparent conductive layer so that the reflected lights on the plurality of laminated thin film surfaces cancel each other by an interference effect. It is used.

As a conventional method for forming a transparent conductive film having high conductivity on the face panel of a cathode ray tube, which not only prevents charging but also shields electromagnetic waves, the face panel is placed in a vapor deposition pot and oxidized. A method for forming an indium compound or a tin oxide compound by vapor deposition (PVD
Method), a method of thermally decomposing an organic compound of indium or tin, a salt solution or the like to form a transparent conductive film on the face panel (CVD method).

[0005]

The transparent conductive film formed by the above-mentioned various methods is sufficiently transparent because it may have a small thickness when used only as an antistatic film, but it is an electromagnetic wave shielding layer. When used as an electrode film or an electrode film, high conductivity is required, so the film thickness must be increased to some extent.
For this reason, there is a problem that the transparency is lowered and the screen is darkened, and the conductive film is colored due to absorption at a specific light wavelength, so that the hue of the transmitted image unnaturally changes. Further, when the PVD method or the CVD method is used, a vacuum or a high temperature is required to form a film, so that a capital investment becomes expensive when forming a transparent conductive film on a large-area substrate, There was a problem that the efficiency was poor and the manufacturing cost was high.

[0006] In order to suppress the equipment investment and efficiently form the transparent conductive film on a large-sized substrate, a coating method has been proposed. For example, a coating material containing an organic indium compound (see Japanese Patent Application Laid-Open No. 52-1497), a coating material in which an indium salt or tin salt is dissolved in water or an organic solvent (Japanese Patent Application Laid-Open No. 63-
64012, JP-A-55-51737, JP-A-58-82407, and JP-A-57-36714.
Japanese Patent Laid-Open No. 60-220507) and the like have been proposed. However, in order to form a transparent conductive film using these paints, heat treatment at a high temperature of 350 ° C. or higher is required after coating the substrate, so that there is a limit to the material of the substrate that can be used and the manufacturing process. There are also many restrictions on the top.

A paint in which fine particles or colloid of a transparent conductive oxide such as tin oxide or indium oxide is dispersed in a polymer solution or a binder resin has also been proposed (Japanese Patent Publication No. Sho-3).
JP-A-5-6616, JP-A-57-85866,
JP-A-58-91777, JP-A-62-2787
No. 05 publication). It is said that the transparent conductive film can be formed at a relatively low temperature by using this paint.

However, in any of the above transparent conductive films,
In order to obtain a practical transparency, it is necessary to reduce the thickness of the coating film, and if it is reduced, the conductivity will decrease. It is insufficient for the purpose, and if the film thickness is increased, the transparency is lowered and the screen becomes dark, so that the use is limited.

As a transparent conductive film having an excellent electromagnetic wave shielding effect and an antireflection effect, a transparent conductive layer composed of metal fine particles having an average particle diameter of 2 to 200 nm and a transparent coating film having a refractive index lower than that is proposed. (Japanese Patent Laid-Open No. 8-778
32). Although this transparent conductive film can be expected to have an electromagnetic wave shielding effect, it absorbs at a specific wavelength of transmitted light depending on the light transmission spectrum of metal fine particles, and the conductive film is colored, causing the hue of the transmitted image to change unnaturally. However, the antireflection effect could not be expected.

In addition to the above, for the purpose of simply forming a conductive film, a method of applying a coating material in which reduced metal colloid particles are dispersed in a photosensitive resin (see Japanese Patent Application Laid-Open No. 4-23484), A method of printing by a screen printing method on a dielectric green sheet using a conductive paste (see Japanese Patent Laid-Open No. 4-19609) is also known.
All of these are opaque, and a transparent conductive film cannot be obtained. The present invention has been made in order to solve the above problems, and therefore, the object thereof is that it can be manufactured at low cost, is excellent in antistatic property and electromagnetic wave shielding property, and is transparent in which the hue of a transmitted image is adjusted. It is to provide a conductive film and a cathode ray tube using the same.

[0011]

In order to solve the above-mentioned problems, according to the present invention, the average particle size is
The total amount of fine silver particles and fine gold particles of 0.05 μm or less is 10
A transparent conductive layer containing at least 1% by weight and having a ratio of the silver fine particles to the gold fine particles in the range of 99: 1 to 50:50 by weight, and laminated on the upper layer and / or the lower layer of the transparent conductive layer. An antireflection colored transparent conductive film comprising at least one transparent antireflection layer, and at least one layer of these layers containing at least one kind of coloring material of blue, purple and black. I will provide a. Hereinafter, the antireflection colored transparent conductive film is simply referred to as “colored conductive film”.

In claim 2, the colored conductive film is
Coloring agent contained in the transparent conductive layer, the content of the silver fine
The total content of the particles and the gold fine particles is preferably 20% by weight or less.

The present invention also provides a cathode ray tube according to claim 3, wherein the colored conductive film according to claim 1 or 2 is formed on the front surface of a face panel.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below. FIG. 1 shows a colored conductive film which is a preferred embodiment of the present invention. In FIG. 1, the colored conductive film 10 is formed on the surface of the transparent substrate 3, and the transparent conductive layer 1 and the transparent antireflection layer 2 are sequentially arranged from the transparent substrate 3 side.
And are stacked.

This transparent conductive layer 1 contains silver and gold in total of 1
0 wt% or more, and the ratio of silver and gold is
It is in the range of 99: 1 to 50:50 by weight, and also with silver .
It contains 20% by weight or less of the total content of gold and a purple pigment. The silver and gold may be contained in the layer as fine particles, or may be in a thin film state in which the fine particles are melted by heating and fused to the transparent substrate 3. Further, the antireflection layer 2 in this embodiment is formed mainly of SiO ₂ . In order to obtain the antireflection effect, the antireflection layer 2 has a refractive index different from that of the transparent conductive layer 1.

In the colored conductive film 10 of this embodiment, since the transparent conductive layer 1 contains silver and gold in an amount of 10% by weight or more,
It has high conductivity and antistatic ability, and also has an effect of shielding harmful electromagnetic waves emitted from a cathode ray tube or the like. Since both the transparent conductive layer 1 and the antireflection layer 2 are transparent, the colored conductive film 10 has a thickness of 400 nm to 800 nm.
Has a high light transmittance in the visible light range. Further, since the antireflection layer 2 is formed, the reflected light is well suppressed.

Further, since the transparent conductive layer 1 contains a proper amount of gold and a purple pigment, for example, silver alone has a thickness of 400 n.
There is absorption in short-wavelength visible light of m to 530 nm, and the hue of the transmitted image looks yellowish and looks unnatural.
It is corrected by absorbing long-wavelength visible light, the light transmission spectrum is flattened over the entire wavelength band of visible light, and the hue of the transmission image is improved to a purple-colored natural color.

In the transparent conductive film 10 of the above embodiment, the antireflection layer 2 is laminated on the transparent conductive layer 1, and the antireflection layer 2 is transparent and has a refractive index different from that of the transparent conductive layer 1. Therefore, the light reflected at the interfaces of a plurality of laminated thin films, for example, the interface between the transparent conductive layer 1 and the antireflection layer 2 or the interface between the transparent conductive layer 1 and the transparent substrate 3 cancels each other due to the interference effect, and the transmitted image The external light reflection that causes the deterioration of visibility is effectively suppressed, and the visibility of the transmitted image is enhanced.

Next, the transparent conductive layer 1 used in the present invention will be described in detail. The transparent conductive layer 1 is basically
The total content of silver and gold is 10% by weight or more. These metals may be in the form of fine particles, may be in the form of a thin film, or may be in the form of a mixture of fine particles and a thin film. These may be in an alloy state or may be a state in which a single metal phase is mixed.

The reason why silver is used in the transparent conductive layer 1 is that silver is relatively easily and inexpensively available as a colloidal dispersion, has high conductivity, is excellent in antistatic property and electromagnetic wave shielding property, and This is because a conductive layer having high transparency can be formed. However, silver is
It must be used in combination with gold .

The mixing ratio of silver and gold is within the range of 99: 1 to 50:50 in terms of silver: gold weight in order to obtain a more flatly corrected light transmission spectrum and economy.

[0022] The content of the metal in the transparent conductive layer 1 10
The reason why the content is more than 10% by weight is that if the content is less than 10% by weight, the electroconductivity is lowered and it becomes difficult to obtain a substantial electromagnetic wave shielding effect.

When the transparent conductive layer 1 contains the metal as fine particles, the average particle diameter of the fine particles is 0.05 μm.
The following is preferable. The reason is that when the average particle size exceeds 0.05 μm, visible light absorption increases when a transparent conductive layer is formed, and it may be difficult to obtain a transparent conductive layer that satisfies both transparency and conductivity. Because there is.

The thickness of the transparent conductive layer 1 is preferably 1 μm or less from the viewpoint of ensuring transparency. In particular, in order to effectively reduce the reflected light by laminating it with the antireflection layer 2, the film thickness is more preferably 0.2 μm or less.

In order to effectively use the transparent conductive layer 1 not only for preventing electrostatic charge but also for shielding electromagnetic waves, it is necessary to design film characteristics corresponding to the frequency of electromagnetic waves to be shielded. Generally, the electromagnetic wave shielding effect is expressed by the following equation (1).

[0026]

[Equation 1]

From the viewpoint of ensuring transparency, the film thickness t is 1 μm.
Since it is preferably m (1 × 10 ⁻⁴ cm) or less,
The formula (1) can be approximately represented by the following formula (2).

[0028]

[Equation 2]

That is, it is understood that the smaller the volume specific resistance value (ρ) of the transparent conductive layer 1 is, the greater the shielding effect against electromagnetic waves in a wide range of frequencies. Generally, the electromagnetic wave shielding effect is effective if S> 30 dB,
Furthermore, if S> 60 dB, it is considered excellent. The frequency of regulated electromagnetic waves is generally 10 kHz to 1000 M.
Since the frequency is in the range of Hz, it is desirable that the volume specific resistance value (ρ) of the transparent conductive layer 1 be 10 ³ Ω · cm or less in order to obtain a good electromagnetic wave shielding effect with a film thickness of 1 μm or less.
This value can be achieved by setting the total content of metals to 10% by weight or more when the transparent conductive layer 1 is formed of, for example, two kinds of silver and gold.

In the colored conductive film of the present invention, the transparent conductive layer 1 includes a visible light wavelength band (400
(nm to 800 nm), and may include inorganic fine particles having transparency. When adding transparent inorganic fine particles,
It is preferable that the transparent conductive layer 1 has conductivity so as not to impair the conductivity. The average particle size of the transparent inorganic fine particles is preferably 0.1 μm or less.

Examples of transparent inorganic fine particles that can be used for this purpose include silicon, aluminum, zirconium,
Examples thereof include cerium, titanium, yttrium, zinc, magnesium, indium, tin, antimony, gallium, and other oxides, complex oxides, and nitrides. In particular, examples of preferable transparent inorganic fine particles having conductivity include oxides such as indium and tin, complex oxides, antimony-doped tin oxide, and the like.

The transparent conductive layer 1 may contain a binder component in order to improve the film strength. Examples of binder components that can be used include, for example, polyester resin, acrylic resin, epoxy resin, melamine resin,
Examples include organic synthetic resins such as urethane resins, butyral resins, and ultraviolet curable resins, hydrolysates of metal alkoxides such as silicon, titanium and zirconium, and organic / inorganic binder components such as silicone monomers and silicone oligomers. .

In order to enhance the affinity between the binder component and the metal, the surface of the metal is coated with a coupling agent such as a silicone coupling agent or a titanate coupling agent, a carboxylate, a polycarboxylate or a phosphate ester. It may be treated with a lipophilic surface treatment agent such as a salt, a sulfonate or a polysulfonate.

The transparent conductive layer 1 can be formed, for example, by the following method. That is, one of them is a transparent conductive material containing a colloidal dispersion liquid containing fine silver particles and fine gold particles having an average particle diameter of 0.05 μm or less, and optionally other transparent inorganic fine particles, a binder, a coloring material, and the like. A layer coating material is prepared and applied uniformly on a substrate 3 such as a cathode ray tube face panel to a thickness such that the ratio of silver and gold in the dried transparent conductive layer 1 is 10% by weight or more. Then, it is dried and baked at 150 ° C. for 1 hour.

The above-mentioned transparent conductive layer coating material contains a plurality of transparent conductive layers each containing fine particles of each metal, and a colloidal dispersion containing the above-mentioned transparent inorganic fine particles, a binder, a coloring agent and the like as required. Layer coatings are prepared, and these coatings are sequentially applied onto the substrate 3 in a thickness such that the ratio of each metal in the dried transparent conductive layer 1 becomes a predetermined value, dried, and baked. It can also be formed by a method. In this method, there is no particular limitation on the order of application.

In the above-mentioned forming method, the method for producing the transparent conductive layer coating material to be used is not particularly limited, but for example, a colloidal liquid in which fine metal particles are dispersed may be added, if necessary, to the fine inorganic particles, binder and coloring material. It can be produced by a commonly used dispersion technique such as an ultrasonic disperser or a sand mill.

Further, in any of the above methods, the coating can be carried out by using a known thin film coating technique such as spin coating, roll coating, knife coating, bar coating, spray coating, dipping or meniscus coating.

In the colored conductive film of the present invention, at least one transparent antireflection layer 2 is laminated on the upper layer and / or the lower layer of the transparent conductive layer 1. Next, the antireflection layer 2 will be described in detail.

The antireflection layer 2 is made of, for example, a transparent oxide such as silicon, aluminum, zirconium, cerium, titanium, yttrium, zinc, magnesium, indium, tin, antimony or gallium, a complex oxide, or a nitride. A coating material (antireflection coating material) containing an inorganic substance or a precursor capable of producing these by baking as a main component, and optionally other components such as a coloring agent is provided as a lower layer or an upper layer of the transparent conductive layer 1. The transparent conductive layer 1 can be formed at the same time as the transparent conductive layer 1 or separately.

A transparent hard layer is formed on the transparent conductive layer 1.
A coat layer is formed, and the refractive index of this hard coat layer is transparent.
Antireflection function by making it different from the conductive layer 1
To protect the transparent conductive layer 1 and prevent reflection.
You can also do it. Form this anti-reflective hard coat layer
Examples of substances that can be M (OR)_mR_n In, M is Si, Ti or Zr and R is C₁
~ C_FourIs an alkyl group of, m is an integer of 1 to 4,
A compound in which n is an integer of 1 to 3 and m + n is 4.
Or one or more of the following:
Mention may be made of mixtures. As an example of this compound
Is, for example, tetraethoxysilane (Si (OC
₂H_Five)_Four) Is preferably used. This anti-reflective hard
The coat layer is a metal oxide forming the antireflection layer 2 described above.
Material, complex oxide, or nitride, or by baking
Precursors capable of producing these and / or
May contain a coloring material or the like.

As the antireflection layer 2, a material having a refractive index different from that of the transparent conductive layer 1 is selected, and if the film thicknesses thereof are appropriately adjusted, the interface of the transparent conductive layer 1 and / or the substrate surface can be obtained. The reflected lights from the light sources cancel each other due to the interference effect, and the antireflection effect can be realized.

In general, the antireflection ability of a thin film is determined by the refractive index and film thickness of the film, and in the case of a multilayer film, the number of laminated films. Now, for example, when a transparent conductive layer is used as a lower layer and an antireflection layer having a low refractive index is formed thereon, when the wavelength of the reflected light to be prevented is λ, the transparent conductive layer and the antireflection layer are The optical thickness of each is λ /
Reflection can be effectively prevented by setting λ / 4, λ / 4, or λ / 2, λ / 4. When a transparent conductive layer is used as an upper layer and an antireflection layer having a high refractive index is formed below the transparent conductive layer, when the wavelength of the reflected light to be prevented is λ, the optics of the transparent conductive layer and the antireflection layer are Reflection can be effectively prevented by setting the target film thickness to λ / 4, λ / 4, or λ / 2, λ / 4. In addition, it is possible to effectively prevent reflection by using a three-layer film structure including an antireflection layer, a transparent conductive layer, and an antireflection layer, and setting optical thicknesses of λ / 4, λ / 2, and λ / 4, respectively. can do.

In particular, considering the ease of manufacture and the economical efficiency, the upper layer of the transparent conductive film has a relatively low refractive index,
SiO ₂ (with a refractive index of 1.4
It is preferable to form the film 6) with a film thickness of λ / 4.

In the above embodiment, the transparent conductive layer 1
A purple pigment is contained therein as a coloring material. Since this purple pigment has a short-wavelength visible light of 400 nm to 530 nm that absorbs visible light, the transparent conductive layer is colored yellow and the hue of the transmitted image looks unnatural, thus correcting the entire visible wavelength band. This has the effect of flattening the transmission spectrum of light over the entire range and improving the hue of the transmission image.

The coloring material that can be preferably used in the colored conductive film of the present invention is a blue, purple or black coloring material. Among them, the violet pigment and the blue pigment are particularly effective for the toning of the transmitted image, and the black pigment has the effect of toning but also the effect of enhancing the color contrast of the transmitted image. However, the colored conductive film of the present invention may contain a coloring material of another color for the purpose of coloring a specific color.

Examples of suitable coloring agents include phthalocyanine blue, cyanine blue, indanthrone blue, dioxazine violet, aniline black, alkali blue, titanium oxide, and the like.
Organic and inorganic pigments such as chromium oxide, iron black, cobalt blue, cerulean blue, zinc chromate, ultramarine, manganese violet, cobalt violet, dark blue, carbon black, and azo dyes, anthraquinone dyes, indigoid dyes, phthalocyanine dyes, carbonium dyes Examples thereof include quinoneimine dyes, methine dyes, quinoline dyes, nitro dyes, nitroso dyes, benzoquinone dyes, naphthoquinone dyes, naphthalimide dyes, perinone dyes, and other blue, purple, or black dyes.

In addition to the above-mentioned usual coloring materials, those having a filter effect of selectively absorbing visible light other than the three primary colors (for example, JP-A-1-320742 and JP-A-3-11532). Japanese Patent Laid-Open No. 3-2540
No. 48, etc.), which obtains a high contrast effect by reducing the transmittance of visible light over the whole (for example, see Japanese Patent Laid-Open No. 6-80903, etc.), minimum reflection in an antireflection film due to interference of a laminate. A material that obtains an antireflection effect by using a coloring material that substantially matches the ratio (see, for example, JP-A-5-203804), or a material that absorbs visible light of a specific wavelength to obtain a natural image that is easy on the eyes ( For example, a coloring material that has been conventionally used or proposed for a transparent conductive film or a face panel of a cathode ray tube such as JP-A-7-151903) can also be used.

One or more of the above-mentioned coloring materials may be contained in any one layer or two or more layers of the transparent conductive layer and the antireflection layer, and the two or more coloring materials are different from each other. It may be included in the layer. Generally, it is preferable that the colorant for toning that improves the hue of the transparent conductive layer 1 be contained in the transparent conductive layer 1.

The kinds and amounts of these coloring materials used are
It should be appropriately selected according to the optical film characteristics of the corresponding colored conductive film. In particular, when a coloring material is mixed in the transparent conductive layer 1, it is preferable to select it so as to be 20% by weight or less of the metal content. 20% by weight of metal content
If it exceeds the range, the conductivity may decrease and the electromagnetic wave shielding effect may decrease.

Generally, the absorbance A of a transparent thin film containing a coloring material is represented by the following formula. A = log ₁₀ (I ₀ / I) = εCD (wherein I ₀ is incident light, I is transmitted light, C is color density, D is optical distance, and ε is molar extinction coefficient.)

In the colored conductive film of the present invention, a coloring material having a molar extinction coefficient ε> 10 is generally used. Further, the blending amount of the coloring material varies depending on the absorbance of the coloring material used, but generally, the absorbance A ₁ of the laminated film and the single layer film containing the coloring material is 0.0004 to 3 abs. It is preferable that the amount be within the range. If these conditions are not met, the transparency and / or toning effect will be reduced. In particular, when the above-mentioned coloring material is blended in the transparent conductive layer 1, a great effect is exhibited in adjusting the transmitted color and the reflected color. However, in this case, when the amount of metal added exceeds 10% by weight, a decrease in conductivity is observed, and when it exceeds 20% by weight,
As described above, the electromagnetic wave shielding effect is impaired.

The cathode ray tube of the present invention is one in which the colored conductive film having any of the above structures is formed on the front surface of the face panel. In this cathode ray tube, since the face panel is prevented from being charged, dust or the like does not adhere to the image display surface, electromagnetic waves are shielded, various kinds of electromagnetic interference are prevented, reflected light is reduced, and residual reflected light is reduced. Also has a color tone close to that of natural light, high transparency, haze is removed, and the transmission spectrum is flattened in the visible light band, so the image does not unnaturally color and is excellent in visibility and easy on the eyes. Becomes

[0053]

EXAMPLES The present invention will be described in more detail below with reference to examples. (Preparation of paint) Preparation of silver colloid: sodium citrate dihydrate (1
4 g), 60 g of a solution in which ferrous sulfate (7.5 g) is dissolved
While maintaining at 5 ° C., 25 g of a solution in which silver nitrate (2.5 g) was dissolved was added to form a silver colloid. The obtained silver colloid was washed with water by centrifugation to remove impurities, and then 38.1 g of pure water was added to prepare a silver colloid for paint. The particle size of the obtained silver colloid particles is 0.005.
It was μm to 0.03 μm. Preparation of gold colloid: Tetrachloroauric acid hydrate (2 g)
A potassium colloid solution (4 g) and trisodium citrate dihydrate (0.025 g) were added to the mixture to form a gold colloid. Preparation of antireflection hard coat paint: tetraethoxysilane (0.8 g) and 0. IN hydrochloric acid (0.8 g) and ethyl alcohol (98.4 g) were mixed to form a uniform solution.

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

(Example 1 ) Preparation of transparent conductive paint: Silver colloid 13.5 g Purple pigment (LIONOGEN VIOLET R6100 manufactured by Toyo Ink Mfg. Co., Ltd.) 0.05 g Gold colloid 6 g Pure water 60.45 g Butyl cellosolve 10.0 g IPA 10.0 g The above components were blended and dispersed with an ultrasonic disperser (“Sonifer 450” manufactured by Central Scientific Trading Co., Ltd.) to prepare a transparent conductive paint.

Film formation: The above transparent conductive paint is applied on the surface of a cathode ray tube panel using a spin coater, and after drying,
Similarly, the antireflection hard coat paint of 1 was applied using a spin coater, and baked at 150 ° C. for 1 hour in a dryer to form a transparent conductive film, whereby a cathode ray tube having an antireflection / high conductive film was prepared.

(Comparative Example 1) Preparation of transparent conductive paint: Silver colloid 15 g Pure water 65 g Butyl cellosolve 10 g IPA 10 g The above ingredients were blended and dispersed with an ultrasonic disperser ("Soniffer 450" manufactured by Central Scientific Trading Co., Ltd.). Then, a transparent conductive paint was prepared.

Film formation: The above transparent conductive paint is applied on the surface of a cathode ray tube panel using a spin coater, and after drying,
Similarly, the antireflection hard coat paint of 1 was applied using a spin coater, and baked at 150 ° C. for 1 hour in a dryer to form a transparent conductive film, whereby a cathode ray tube having an antireflection / high conductive film was prepared.

Comparative Example 2 Preparation of transparent conductive paint: Antimony-doped tin oxide fine powder (Sumitomo Osaka Cement Co., average particle size 0.01 μm) 1.5 g Pure water 78.5 g Butyl cellosolve 10.0 g IPA 10.0 g The above components were blended and dispersed with an ultrasonic disperser ("Soniffer 450" manufactured by Central Scientific Trading Co., Ltd.) to prepare a transparent conductive paint.

Film formation: The above transparent conductive paint is applied to the surface of a cathode ray tube panel using a spin coater, and after drying,
Similarly, the antireflection hard coat paint of 1 was applied using a spin coater, and baked at 150 ° C. for 1 hour in a dryer to form a transparent conductive film, whereby a cathode ray tube having an antireflection / high conductive film was prepared.

For each of the samples of Example 1 and Comparative Examples 1 and 2, the conductive film evaluation test was performed. The evaluation items and their testers (or test methods) are described below. (Film evaluation method) Transmittance: "Automatic Haze meter H III DP" manufactured by Tokyo Denshoku Co., Ltd. Haze: "Automatic Haze meter H III DP" manufactured by Tokyo Denshoku Co., Ltd. Surface resistance value: "Loresta AP" manufactured by Mitsubishi Petrochemical ( 4-end needle method) Reflectivity: EG & G GAMMA SCIENTIFIC “MODEL C-11” Reflective color: Minolta Camera “CR-300” Scratch resistance: After reciprocating the film surface 50 times with an eraser under a load of 1 kg, Visual evaluation of scratches on the film surface. ○: No scratches △: Slightly scratches ×: Many scratches Visibility: Comprehensive evaluation including low reflection performance, reflected color, and transmitted color ○: Good △: Slightly bad ×: Poor Transmission spectrum: "U-Best50" manufactured by JASCO Corporation The results of the evaluation test are shown in Table 1 and FIG.

[0067]

[Table 1]

From Table 1, it can be seen that the sample of Comparative Example 2 containing no silver and gold has a high transmittance but a high surface resistance, and thus a low electromagnetic wave shielding performance. The samples of Example 1 and Comparative Example 1 containing silver and gold each had a surface resistance of 1
It is in the order of 0 ² Ω / □, which means that high electromagnetic wave shielding performance is obtained.

[0069]

[0070]

[0071]

In Table 1 and FIG. 2, Example 1 containing silver, gold and a violet pigment is similar to Comparative Example 1 except that the gold and violet pigment are not contained, and the transmission spectrum is flattened. Achieved, and the yellowish transmitted color as a whole is greatly reduced. Further, regarding the reflection, since the reflectance is lowered and the reflection color is close to a natural color, a great effect of improving the visibility is recognized.

As described above, in the colored conductive film of the present invention, the light transmission spectrum is flattened over the entire visible light band, the reflected color and the contrast are improved, and the antistatic property and the electromagnetic wave shielding property are excellent. Because
Not only is it suitable for use as a face panel of a cathode ray tube, but it can also be used advantageously for other display plates such as liquid crystal display plates, electroluminescence display plates, plasma display plates, and electroluminescent display plates.

[0074]

The colored transparent conductive film of the present invention is characterized in that, in claim 1, the total content of silver and gold is 10% by weight or more.
The ratio of silver and gold is in the range of 99: 1 to 50:50 by weight.
The transparent conductive layer inside and the upper layer of the transparent conductive layer and / or
Or at least one transparent antireflection layer laminated as a lower layer, and at least one layer of these layers contains at least one colorant of blue, purple and black Therefore, the transmission spectrum of light can be adjusted without impairing the antistatic property and the electromagnetic wave shielding property, and the hue and contrast are optimized, and the clear transmission image with good visibility with reduced reflection is obtained. Will be available.

In the second aspect, when the coloring material is contained in the transparent conductive layer and the content thereof is 20% by weight or less of the metal content, the antistatic property, the electromagnetic wave shielding property and the transparency are impaired. It becomes possible to suitably adjust the hue and the contrast.

In claim 3, the cathode ray tube of the present invention comprises:
Since any one of the above colored conductive films is formed on the front surface of the face panel, it is difficult for dust to adhere to the display surface and harmful electromagnetic interference is prevented, and the hue of the transmitted image is natural and the contrast is good. In addition, the difficulty of viewing due to reflection is reduced, and a clear transmitted image with good visibility can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a colored conductive film of the present invention.

FIG. 2 is a graph showing a light transmission spectrum in a visible light band of Example 1 of the present invention in comparison with a comparative example.

[Explanation of symbols]

1 ... Transparent conductive layer 2 ... Antireflection layer 3 ... Transparent substrate 10 ... Antireflection colored transparent conductive film

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI H04N 5/64 541 G02B 1/10 A (72) Inventor Kazunori Mori Sumitomo Osaka Cement Co., Ltd. Materials Division (56) Reference JP-A-8-77832 (JP, A) JP-A-3-11532 (JP, A) JP-A-1-186737 (JP, A) JP-A-1-171299 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H05K 9/00

Claims (3)

(57) [Claims] 1. A silver having an average grain size of 0.05 μm or less.
Containing fine particles and gold particles in a total amount of 10% by weight or more, and
The ratio of the fine silver particles and the fine gold particles is 99: 1 by weight.
To 50:50, and at least one transparent antireflection layer laminated on an upper layer and / or a lower layer of the transparent conductive layer, and at least one of these layers. An antireflection colored transparent conductive film, wherein the layer contains at least one colorant selected from blue, purple and black. 2. A colorant is contained in the transparent conductive layer, the content of which is 2 times the total content of the silver fine particles and the gold fine particles.
The antireflection colored transparent conductive film according to claim 1, wherein the content is 0% by weight or less. 3. A cathode ray tube, comprising the antireflection colored transparent conductive film according to claim 1 or 2 formed on the front surface of a face panel.