JPH10208672A - Cathode-ray tube having electric field leakage preventive coat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cathode-ray tube having an electric field leakage preventive coat which prevents the aged deterioration of the surface sheet resistance value of the first layer of a conductive high refractive index, of a two-layer coat which consists of the first layer of conductive high refractive index and the second layer of a low refractive index. SOLUTION: This cathode-ray tube has an electric field leakage preventive coat formed by attaching a two-layer coat which consists of the first layer 14 of a conductive high refractive index with the main component of metal fine grains, and the second layer 15 of a low refractive index with the main component of silicon dioxide (SiO2 ) or magnesium fluoride (MgF2 ), on the surface of a panel face plate 1A. In this case, in the first layer 14 of the conductive high refractive index, one or more sorts of metals in the noble metal elements of the group of gold (Au), sliver (Ag), and platinum (Pt) are used as the metal fine grains.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cathode ray tube having an electric field leakage prevention coating, and more particularly to a two-layer structure comprising a conductive high refractive index first layer and a low refractive index second layer on a surface of a face plate of a panel. The present invention relates to a cathode ray tube having an electric field leakage prevention coating to which a coating is attached.

[0002]

2. Description of the Related Art Conventionally, in a cathode ray tube, a two-layer coating consisting of a first layer having a high refractive index and a second layer having a low refractive index is formed on the surface of a face plate of a panel so as to prevent reflection of light on the face plate. 2. Description of the Related Art There has been known a cathode ray tube in which an antistatic effect for preventing an electric shock at the time of contact with a face plate and a high contrast of a displayed image, that is, a cathode ray tube having a two-layer coating, are known.

The function of preventing reflection of light in a cathode ray tube having the known two-layer coating is performed by the interference of light by the two-layer coating composed of a first layer having a high refractive index and a second layer having a low refractive index. (Anti-reflection) effect is achieved.

The antistatic function for preventing electric shock in a cathode ray tube having the known two-layer coating is provided by a high-refractive-index two-layer coating composed of a high-refractive-index first layer and a low-refractive-index second layer. For the first layer, for example, conductive fine particles in which tin oxide (SnO ₂ ) and antimony oxide (Sb ₂ O ₃ ) are combined, or tin oxide (SnO ₂ ) and indium oxide (In ₂ O ₃ )
The above-described anti-reflection is achieved by using a conductive high-refractive index first layer in which conductive fine particles in combination with the above are combined, and setting the surface sheet resistance of the conductive high-refractive index first layer to 10 KΩ to 100 MΩ / □. (Anti-reflection) effect and electric shock prevention effect are achieved together.

Further, the function of increasing the contrast of a display image in a cathode ray tube having the above-mentioned known two-layer coating is to provide a high-refractive-index two-layer coating composed of a high-refractive-index first layer and a low-refractive-index second layer. By mixing a predetermined amount of a dye of a specific color into the first rate layer, the above-described anti-reflection (anti-reflection) effect, anti-shock effect, and high contrast effect can be achieved.

Japanese Patent Laid-Open Publication Nos. Hei 3-93136, Hei 5-113505, Hei 5-343008, and Hei 7-312170 disclose technical means for achieving the above functions. Etc.

In addition, conventionally, in a cathode ray tube, a two-layer coating composed of a first layer having a high refractive index and a second layer having a low refractive index is adhered and formed on the surface of the face plate of the panel portion to thereby form the first layer having a high refractive index. A conductive high refractive index first layer in which metal fine particles are mixed is used for the layer, and the surface sheet resistance of the conductive high refractive index first layer is 1
A cathode ray tube having a resistance of not more than KΩ / □ and preventing an electric field generated in the cathode ray tube from leaking from the surface of the face plate of the panel, that is, a cathode ray tube having an electric field leakage prevention coating, is also known. Magazine "Industrial Materials", No.4
Vol. 4, No. 9 (August 1996), 68-71
Some are listed on the page.

[0008]

In the cathode ray tube having the known two-layer coating, the first layer having a high refractive index has, for example, tin oxide (SnO ₂ ) and antimony oxide (Sb ₂ O ₃ ).
And tin oxide (Sn)
Although the conductive high refractive index first layer in which conductive fine particles in which O ₂ ) and indium oxide (In ₂ O ₃ ) are combined is used, the surface sheet resistance of the conductive high refractive index first layer is used. Is from 10 KΩ to 100 MΩ / □, it is not possible to prevent the electric field generated in the cathode ray tube from leaking from the surface of the face plate of the panel to the outside in the first layer of the conductive high refractive index. There is a problem that a cathode ray tube having a layer coating cannot be used as a cathode ray tube having an electric field leakage prevention function.

On the other hand, the cathode ray tube having the above-mentioned known electric field leakage preventing coating has a surface sheet resistance of the conductive high refractive index first layer of 1 KΩ / □ or less. Although it can be used as a tube,
The conductive metal fine particles mixed in the conductive high refractive index first layer have a particle size of 100 nm or less and show an active state. Since it is in an active state and is easily oxidized, there is a problem that the surface sheet resistance of the conductive high refractive index first layer is deteriorated with time.

[0010] The cathode ray tube having the above-mentioned known electric field leakage prevention coating is a two-layer coating consisting of a conductive high-refractive-index first layer and a low-refractive-index second layer. Although the rise in the blackness of the body color of the cathode ray tube due to the increase in light reflection is suppressed by the light absorption of the metal fine particles mixed in the conductive high refractive index first layer, a high contrast can be obtained. Since the spectral transmittance of the metal fine particle layer differs depending on the light wavelength, the body color of the cathode ray tube is colored to a color other than black. For example, the spectral transmittance of the mixed metal fine particle layer is 4% of the light wavelength.
When it is low around 20 nm and shows an absorption peak, the two-layer coating composed of the high-refractive-index first layer and the low-refractive-index second layer has an amber color as a whole, and becomes unsuitable for display. There is a problem.

The present invention solves all of these problems. A first object of the present invention is to provide a two-layer coating comprising a conductive high refractive index first layer and a low refractive index second layer. An object of the present invention is to provide a cathode ray tube having an electric field leakage prevention coating which prevents the surface sheet resistance of the conductive high refractive index first layer from deteriorating over time.

A second object of the present invention is to provide a surface sheet of a first conductive high refractive index layer in a two-layer coating comprising a first conductive high refractive index layer and a second low refractive index second layer. An object of the present invention is to provide a cathode ray tube having an electric field leakage prevention coating which prevents deterioration of the resistance value over time and prevents coloring of the body color of the cathode ray tube.

[0013]

In order to achieve the first object, a cathode ray tube having an electric field leakage prevention coating according to the present invention is provided on a surface of a face plate of a panel section with a conductive material mainly composed of fine metal particles. When a two-layer coating composed of a first refractive index layer and a low refractive index second layer is applied, the conductive high refractive index first
The layer is provided with a first means formed by mixing one or more kinds of fine metal particles in a noble metal element belonging to the group of gold (Au), silver (Ag) or platinum (Pt).

According to the first means, as the metal fine particles of the first layer of the conductive high refractive index, a noble metal of the gold (Au), silver (Ag) or platinum (Pt) group which is always in a chemically stable state. Using one or more kinds of metal fine particles among the elements,
Not only can the surface sheet resistance value of the conductive high refractive index first layer be 1 KΩ / □ or less having an electric field leakage preventing function, but also one of the noble metal elements in the conductive high refractive index first layer Since the above metal fine particles are in a chemically stable state and are hardly oxidized, the surface sheet resistance of the conductive high refractive index first layer does not deteriorate over a long period of time.

Further, in order to achieve the second object,
When the cathode ray tube having the electric field leakage prevention coating according to the present invention has a two-layer coating composed of a conductive high refractive index first layer and a low refractive index second layer mixed with metal fine particles adhered to the panel faceplate surface. In addition, a conductive high refractive index first layer is formed of gold (A
u), one or more kinds of fine metal particles in a noble metal element belonging to the genus silver (Ag) or platinum (Pt) are mixed and formed;
A second means is provided in which a low-refractive-index second layer is added with a pigment such as a pigment or a dye so as to have a selective absorption characteristic of a light wavelength.

According to the second means, similarly to the first means, as the metal fine particles mixed with the conductive high refractive index first layer, gold (Au), silver ( A
g) or one or more kinds of noble metal elements of the platinum (Pt) genus, and the surface sheet resistance of the conductive high refractive index first layer is reduced by 1K having an electric field leakage preventing function.
In addition to being able to have a low resistance value of Ω / □ or less, one or more kinds of metal fine particles among the noble metal elements in the conductive high refractive index first layer are in a chemically stable state and are hardly oxidized. In addition to the fact that the surface sheet resistance of the conductive high refractive index first layer does not deteriorate over a long period of time, the dye having a complementary color relationship to the coloration of the body color of the cathode ray tube is added to the low refractive index second layer. , The body color of the cathode ray tube can be made achromatic.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In a preferred embodiment of the present invention, a cathode ray tube having an electric field leakage prevention coating has a conductive high refractive index first layer mainly composed of fine metal particles and silicon dioxide on a surface of a panel face plate. (SiO ₂ ) or magnesium fluoride (MgF ₂ )
And a conductive high-refractive-index first layer formed of one of gold (Au), silver (Ag) or platinum (Pt) -based noble metal elements as metal fine particles. More than one kind of metal is used.

In one embodiment of the present invention, the conductive high refractive index first layer in the above-described embodiment of the present invention has a light absorption property and a luminous transmittance of 50 to 50. 9
It is within the range of 0%.

In another embodiment of the present invention, the second layer having a low refractive index in the above-described embodiment of the present invention has a selective absorption characteristic of a light wavelength by adding a pigment such as a pigment or a dye. What you are doing.

One preferable example of the embodiment of the present invention is a metal fine particle having a conductive high refractive index first layer formed on the surface of a face plate of a panel section by applying the two-layer coating in the above embodiment of the present invention. The dispersion liquid is applied, the coated surface is dried to form a conductive high refractive index first layer, and an alcohol solution for forming a low refractive index second layer is coated on the conductive high refractive index first layer. Then, the applied surface is fired at a temperature in the range of 160 to 175 ° C. to adhere and form the low refractive index second layer.

In another preferred embodiment of the present invention, the two-layer coating of the above-described embodiment of the present invention is applied to a metal fine particle for forming a conductive high refractive index first layer on the surface of a face plate of a panel. Apply the dispersion and apply the coated surface to 70 to 1
Heat and dry to a temperature in the range of 30 ° C.
An alcohol solution for forming a low refractive index second layer is coated on the conductive high refractive index first layer, and the coated surface is baked at a temperature in the range of 160 to 175 ° C. to form a low refractive index layer. The second layer is formed by adhesion.

According to the above-described embodiment of the present invention, the first high-refractive-index layer and the second low-refractive-index layer mainly composed of fine metal particles are formed on the surface of the face plate of the panel portion of the cathode ray tube. When depositing the two-layer coating, the metal fine particles used for the conductive high refractive index first layer include gold (Au), silver (Ag), or platinum (Pt), which is always in a chemically stable state.
Using one or more kinds of fine metal particles among the noble metal elements of the genus, thereby reducing the surface sheet resistance of the first layer of conductive high refractive index to a low resistance of 1 KΩ / □ or less which can achieve an electric field leakage prevention function. In addition to the above, the fine particles of one or more of the noble metal elements belonging to the group of gold (Au), silver (Ag) or platinum (Pt) used for the conductive high refractive index first layer are always Since each of them is in a chemically stable state and is hardly oxidized, the surface sheet resistance of the conductive high refractive index first layer does not deteriorate for a long period of time.

According to another embodiment of the present invention, a conductive high-refractive-index first layer mainly composed of metal fine particles and a low-refractive-index layer are provided on the surface of a face plate of a panel section of a cathode ray tube. When attaching a two-layer coating consisting of the second layer,
The fine metal particles used for the first layer of the conductive high refractive index include one or more metals among the noble metal elements of the gold (Au), silver (Ag) or platinum (Pt) group, which are always in a chemically stable state. Fine particles are used, whereby the surface sheet resistance of the conductive first layer having a high refractive index can be reduced to a low resistance value of 1 KΩ / □ or less which can achieve an electric field leakage prevention function, and the conductive high refractive index can be obtained. One or more kinds of fine metal particles among the noble metal elements belonging to the genus gold (Au), silver (Ag) or platinum (Pt) used for the first layer are always in a chemically stable state, and all of them are oxidized. Because of the difficulty, not only does the surface sheet resistance of the conductive first layer of high refractive index deteriorate over a long period of time, but also the body of the cathode ray tube is provided in the second layer of low refractive index. Pigments that are complementary to color coloring Since the addition of the dye postal, etc.,
The coloring of the body color of the cathode ray tube can be complemented to make it achromatic.

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic sectional view showing an embodiment of a cathode ray tube having an electric field leakage prevention coating according to the present invention, in which the cathode ray tube is a color cathode ray tube.

In FIG. 1, 1 is a panel portion, 1A is a face plate, 2 is a neck portion, 3 is a funnel portion, 4 is a fluorescent film, 5 is a two-layer coating, 6 is a shadow mask, 7 is an internal magnetic shield, 8 is a deflection yoke, 9 is a purity adjustment magnet, 10 is a center beam static convergence adjustment magnet, 11 is a side beam static convergence adjustment magnet, 12 is an electron gun,
13 is an electron beam.

A glass vacuum envelope (bulb) constituting a color cathode ray tube has a rectangular panel section 1 disposed on the front side and an elongated neck section 2 containing an electron gun 12 therein. And a funnel 3 having a substantially funnel shape connecting the panel 1 and the neck 2. Panel part 1
Has a face plate 1A on the front surface, a fluorescent film 4 is formed on the inner surface of the face plate 1A, and a two-layer coating 5 that functions to prevent electric field leakage is formed on the surface of the face plate 1A. The shadow mask 6 includes the panel unit 1
It is attached inside so as to face the fluorescent film 4. An internal magnetic shield 7 is provided inside a joint portion between the panel portion 1 and the funnel portion 3, and a deflection yoke 8 is arranged outside the joint portion between the funnel portion 3 and the neck portion 2 in use.
Three electron beams 13 emitted from the electron gun 12 (FIG. 1)
(Only one is shown) is deflected in a predetermined direction by a deflection yoke 8 and then strikes the fluorescent film 4 through an electron beam passage hole (not shown) of the shadow mask 6. A purity adjustment magnet 9, a center beam static convergence adjustment magnet 10, and a side beam static convergence adjustment magnet 11 are arranged outside the neck portion 2 side by side.

The operation of the color cathode ray tube having the above-described structure, that is, the image display operation, is exactly the same as the image display operation of the known color cathode ray tube. Therefore, the description of the image display operation of the color cathode ray tube is omitted. I do.

FIG. 2 is a sectional view showing a part of a first example of the two-layer coating 5 used in the color cathode ray tube of the present embodiment shown in FIG.

In FIG. 2, reference numeral 14 denotes a conductive high refractive index first material.
The layer 15 is a second layer having a low refractive index, and the same components as those shown in FIG. 1 are denoted by the same reference numerals.

In this case, the two-layer coating 5 is composed of a conductive high refractive index first layer 14 mainly composed of silver fine particles adhered and formed on the panel portion 1 face plate 1A, and a conductive high refractive index first layer 14. Silicon dioxide (Si) deposited on layer 14
O ₂ ), and the thickness of the conductive high refractive index first layer 14 is about 40 nm, and the thickness of the low refractive index second layer 15 is about 70 nm.

FIG. 6 shows a two-layer coating 5 of the first configuration example.
It is a flowchart which shows the formation procedure at the time of attaching and forming to the face plate 1A.

The procedure for forming the two-layer coating 5 of the first configuration example will be described with reference to this flowchart.

First, in step S1, a reinforcing bracket is mounted around the panel section 1 of the color cathode ray tube.

Next, in step S2, the surface of the face plate 1A of the panel portion 1 of the color cathode ray tube is polished with an abrasive.

Next, in step S3, the polished face plate 1A is washed with a shower of tap water and pure water.

Subsequently, in step S4, the washed panel unit 1 face plate 1A is dried.

Next, in step S5, the panel unit 1
Is set to about 40 ° C.

Next, in step S6, silver (A
g) An aqueous dispersion (dispersion of fine metal particles) composed of a high-boiling solvent containing fine particles as a solid content is spin-coated on the face plate 1A of the panel section 1 to form a conductive high refractive index first layer 1
4 is deposited.

Subsequently, in step S7, the face plate 1A is heated at a temperature of about 100 ° C., and the adhered conductive high refractive index first layer 14 is dried.

Next, in step S8, the panel unit 1
Is set to about 40 ° C., an alcohol solution of silicon alkoxide is added to the conductive high refractive index first.
A low-refractive-index second layer 15 is applied by spinning on the layer 14.

Thereafter, in step S9, the face plate 1A is heated at a temperature of about 165 ° C., and the low-refractive-index second layer 15 is deposited and baked, so that the first configuration example is formed on the panel unit 1 face plate 1A. A two-layer coating 5 is formed.

FIG. 10 is a characteristic diagram showing the spectral transmittance of the color cathode ray tube having the two-layer coating 5 of the first configuration example obtained by such a manufacturing process, wherein the vertical axis represents the light transmittance expressed in%. And the horizontal axis is the light wavelength expressed in nm.

As shown in FIG. 10, the second configuration example 2
The color cathode ray tube having the layer coating 5 has a light wavelength of 420 nm.
Shows a slight light absorption in the vicinity of, but the light absorption in the visible region is almost flat. Further, the color cathode ray tube having the two-layer coating 5 of the first configuration example has an object color according to JIS C 8729 "L'a'b 'color system and L'u'v' color system." A ′ = − 2 to +2 and b ′ = 0 to +4, and the visual evaluation of the appearance of the panel unit 1 face plate 1A was almost achromatic. Further, the color cathode ray tube having the two-layer coating 5 of the first configuration example has a surface sheet resistance of about 500Ω / □ and a leakage electric field strength of 0.5 in ELEF (frequency band of 5 Hz to 2 kHz).
V / m is 0.5 V / m in VLEF (frequency band of 2 kHz to 400 kHz), which sufficiently satisfies the strictest TCO standard for leakage electric field strength. In addition, the color cathode ray tube having the two-layer coating 5 of the first configuration example has a luminous reflectance of 0.7%, a luminous transmittance of 72%, and a black body color of the color cathode ray tube due to an anti-reflection effect. The uplift of the is canceled.

FIG. 3 is a sectional view showing a part of a second example of the two-layer coating 5 used in the color cathode ray tube of the present embodiment shown in FIG.

In FIG. 3, reference numeral 15A denotes a third layer having a low refractive index, and the same reference numerals are given to the same components as those shown in FIGS. 1 and 2.

In this case, the two-layer coating 5 is composed of a conductive high-refractive-index first layer 14 mainly composed of silver fine particles adhered and formed on the faceplate 1A of the panel portion 1 and a conductive high-refractive-index first layer 14. Silicon dioxide (Si) deposited on layer 14
O ₂ ) low-refractive-index second layer 15 and silicon dioxide (SiO ₂ ) partially deposited on low-refractive-index second layer 15
And a low-refractive-index third layer 15 </ b> A having an uneven surface.
The thickness of the conductive high refractive index first layer 14 is about 40 nm, the thickness of the low refractive index second layer 15 is about 70 nm,
The thickness of the low refractive index third layer 15A is about 10 nm at the thickest part.

In the color cathode-ray tube having the two-layer coating 5 of the second configuration example, the low refractive index third layer 15 having irregularities is provided.
A, the third layer 15A having a low refractive index slightly
In this case, scattering of extraneous light occurs, and it is possible to reduce specular reflection which is insufficient only by the antireflection effect of the two-layer coating 5.

Here, FIG. 7 shows a two-layer coating 5 of the second configuration example.
It is a flowchart which shows the formation procedure at the time of attaching and forming to the face plate 1A.

The procedure for forming the two-layer coating 5 of the second configuration example will be described with reference to this flowchart.

The steps S1 to S8 are the same as the steps S1 to S8 in the procedure for forming the two-layer coating 5 of the first configuration example described above.

Subsequently, in step S10, the face plate 1A is heated at a temperature of about 60 ° C., and the applied low refractive index second layer 15 is dried.

Next, in step S11, an alcohol solution of silicon alkoxide having a different composition from the alcohol solution used in step S8 is set in a state where the temperature of the panel unit 1 is set to about 50 ° C. The low-refractive-index third layer 15 is partially applied onto the low-refractive-index second layer 15.
A is applied.

Thereafter, in step S12, the face plate 1A is heated at a temperature of about 165 ° C., and the low-refractive-index second layer 15 and the low-refractive-index third layer 15A are respectively deposited and fired, so that The two-layer coating 5 of the second configuration example is formed on the plate 1A.

The color cathode ray tube having the two-layer coating 5 of the second configuration example has almost the same spectral transmittance as the color cathode ray tube having the two-layer coating 5 of the first configuration example shown in FIG. It will be the same. In the color cathode ray tube having the two-layer coating 5 of the second configuration example, the light transmission color is a ′ = − 2 to +
2, b ′ = 0 to +4, which is almost the same as the light transmission color of the color cathode-ray tube having the two-layer coating 5 of the first configuration example. It is almost achromatic. Furthermore, the second
The color cathode ray tube having the two-layer coating 5 of the configuration example has a surface sheet resistance of about 200Ω / □ and a leakage electric field strength of E.
The LEF is 0.4 V / m and the VLEF is 0.6 V / m, which also sufficiently satisfies the TCO standard. In addition, the color cathode ray tube having the two-layer coating 5 of the second configuration example has a luminous reflectance of 0.8%, a luminous transmittance of 60%, and a black body color of the color cathode ray tube due to an anti-reflection effect. The uplift of the is canceled.

FIG. 4 is a sectional view showing a part of a third example of the two-layer coating 5 used in the color cathode ray tube of the present embodiment shown in FIG.

In FIG. 4, reference numeral 14A denotes a convex portion of the conductive high refractive index first layer 14, and the same components as those shown in FIGS. 1 and 2 are denoted by the same reference numerals. .

In this case, the two-layer coating 5 is a silver fine particle adhered and formed on the faceplate 1A of the panel portion 1 and has a conductive high refractive index first layer 14 partially having a convex portion 14A; Conductive high refractive index first layer 14 including convex portion 14A
And a low refractive index second layer 15 of silicon dioxide (SiO ₂ ) formed thereon.
The thickness of the flat part of the layer 14 is about 30 nm, the thickness of the convex part 14A is about 15 nm at the thickest part, and the thickness of the low refractive index second layer 15 is about 70 nm.

In the color cathode ray tube having the two-layer coating 5 of the third configuration example, since the convex portion 14A is partially provided in the conductive high refractive index first layer 14, the two layer coating of the second configuration example is provided. As in the case of the color cathode ray tube having the coating 5, scattering of extraneous light occurs at these projections 14A slightly,
It is possible to reduce specular reflection, which is insufficient only by the antireflection effect of the two-layer coating 5.

Here, FIG. 8 shows a two-layer coating 5 of the third configuration example.
It is a flowchart which shows the formation procedure at the time of attaching and forming to the face plate 1A.

The procedure for forming the two-layer coating 5 of the third configuration example will be described with reference to this flowchart.

The steps S1 to S4 are the same as the steps S1 to S4 in the procedure for forming the two-layer coating 5 of the first configuration example described above.

Subsequently, in step S13, the temperature of the panel section 1 is set to be about 55 ° C.

Next, in step S14, silver (A
g) An aqueous dispersion (a metal fine particle dispersion) composed of a high boiling point solvent containing fine particles in a solid content is spray-coated on the face plate 1A of the panel portion 1 and a conductive high refractive index partially having a convex portion 14A. A first layer 14 is applied.

Next, in step S15, the face plate 1A is heated at a temperature of about 75 ° C. to dry the conductive high refractive index first layer 14 having the protruding portions 14A.

Next, in step S16, with the temperature of the panel unit 1 set to about 40 ° C., an alcohol solution of silicon alkoxide is applied onto the conductive high refractive index first layer 14 having the projections 14A. Spin coating is applied, and the low refractive index second layer 15 is applied.

Thereafter, in step S17, the face plate 1A is heated at a temperature of about 165 ° C., and the low refractive index second layer 15 is deposited and baked, so that the third configuration example is formed on the panel unit 1 face plate 1A. A two-layer coating 5 is formed.

The color cathode ray tube having the two-layer coating 5 of the third configuration example has almost the same spectral transmittance as that of the color cathode ray tube having the two-layer coating 5 of the first configuration example shown in FIG. It will be the same. In the color cathode-ray tube having the two-layer coating 5 of the third configuration example, the light transmission color is a ′ = − 1 to +
1, b ′ = − 1 to +1; the light transmission color of the color cathode ray tube having the two-layer coating 5 of the second configuration example is substantially the same as that of the color cathode ray tube in the outline;
The appearance evaluation of A is almost achromatic. Further, the color cathode ray tube having the two-layer coating 5 of the third configuration example has a surface sheet resistance of about 800Ω / □, a leakage electric field strength of 0.8 V / m in ELEF, and 0.8 V in VLEF.
/ M, which also meets the TCO standard. In addition, the color cathode ray tube having the two-layer coating 5 of the third configuration example has a luminous reflectance of 0.8%, a luminous transmittance of 65%, and a black body color of the color cathode ray tube due to an anti-reflection effect. The uplift of the is canceled.

FIG. 5 is a sectional view showing a part of a fourth example of the two-layer coating 5 used in the color cathode ray tube of the present embodiment shown in FIG.

In FIG. 5, the same components as those shown in FIGS. 1 and 2 are denoted by the same reference numerals.

In this case, the two-layer coating 5 is composed of a conductive high refractive index first layer 14 composed mainly of silver fine particles adhered and formed on the panel portion 1 face plate 1A, and a conductive layer including the convex portions 14A. And a low refractive index second layer 15 of silicon dioxide (SiO ₂ ) formed on the conductive high refractive index first layer 14. The conductive high refractive index first layer 14 has a thickness of about 40 nm.
The thickness of the low refractive index second layer 15 is about 70 nm.

Here, FIG. 9 shows a two-layer coating 5 of the fourth configuration example.
It is a flowchart which shows the formation procedure at the time of attaching and forming to the face plate 1A.

The procedure for forming the two-layer coating 5 of the fourth configuration example will be described with reference to this flowchart.

The steps S1 to S6 are the same as the steps S1 to S6 in the procedure for forming the two-layer coating 5 of the first configuration example described above.

Subsequently, in step S18, the face plate 1A is heated at a temperature of about 50 ° C., and the conductive high refractive index first layer 14 is dried.

Next, in step S19, with the temperature of the panel section 1 set to about 40 ° C., an alcohol solution of silicon alkoxide is spin-coated on the first conductive high refractive index layer 14, and The second layer of refractive index 15 is applied.

Then, in step S20, the face plate 1A is heated at a temperature of about 165 ° C., and the second low-refractive-index layer 15 is deposited and baked, so that the fourth configuration example is formed on the face plate 1A of the panel unit 1. A two-layer coating 5 is formed.

FIG. 11 is a characteristic diagram showing the spectral transmittance of a color cathode ray tube having the two-layer coating 5 of the fourth configuration example obtained by the above manufacturing process. And the horizontal axis is the light wavelength expressed in nm.

As shown in FIG. 11, the second configuration example 2
The color cathode ray tube having the layer coating 5 has a light wavelength of 420 nm.
Is slightly larger than the same light absorption of the color cathode ray tube having the two-layer coating 5 of the first to third configuration examples, but the light absorption in the visible region is almost flat. . In the color cathode ray tube having the two-layer coating 5 of the fourth configuration example, the light transmission color is a ′ = − 3 to + ′.
3, b ′ = + 8 to +15, and the light transmission color b ′ shows a slightly larger value than the same light transmission color b ′ of the color cathode ray tube having the two-layer coating 5 of the first to third configuration examples. The light transmission color of the color cathode ray tube having the two-layer coating 5 of the first to third configuration examples is substantially the same as that of the color cathode ray tube, and the appearance evaluation of the panel unit 1 face plate 1A by visual observation is slightly amber colored. It is. Further, the color cathode ray tube having the two-layer coating 5 of the fourth configuration example has a surface sheet resistance of about 5
00Ω / □, leakage electric field strength is 0.5V in ELEF
/ M, 0.4 V / m in VLEF and TCO
Standards are fully satisfied. In addition, 2 of the fourth configuration example
The color cathode ray tube having the layer coating 5 has a luminous reflectance of 0.5.
With a luminous transmittance of 7% and a luminous transmittance of 70%, the black rise of the body color of the color cathode ray tube due to the anti-reflection effect is canceled.

In this case, in the two-layer coating 5 of the fifth configuration example, a blue pigment, for example, an anthraquinone-based blue pigment is dispersed in the second layer 15 having a low refractive index. Can be obtained.

The color cathode-ray tube having the two-layer coating 5 of the fifth configuration example is different from the color cathode-ray tube having the two-layer coating 5 of the fourth configuration example in that the face plate 1A of the color cathode-ray tube is slightly colored amber. It is supplemented by a certain blue pigment.

The procedure for forming the two-layer coating 5 of the fifth configuration example on the face plate 1A is as follows. In most steps, the two-layer coating 5 of the fourth configuration example shown in FIG. The procedure is the same as when forming the two-layer coating 5 of the fifth configuration example, but only the step S19 in the forming procedure when forming and depositing the two-layer coating 5 on the plate 1A is the silicon alkoxide solid content. In that an alcohol solution containing an anthraquinone-based blue pigment in an amount of about 5 to 15% is used. .

Here, FIG. 12 is a characteristic diagram showing the spectral transmittance of a color cathode ray tube having the two-layer coating 5 of the fifth configuration example, wherein the vertical axis is the light transmittance expressed in% and the horizontal axis is Is nm
Is the light wavelength represented by

As shown in FIG. 12, 2 of the fifth configuration example
The color cathode ray tube having the layer coating 5 has a light wavelength of 420 nm.
Is similar to that of the color cathode-ray tube having the two-layer coating 5 of the first to third configuration examples in the same manner as the color cathode-ray tube having the two-layer coating 5 of the fourth configuration example. In addition to being slightly larger, the absorption of light in the visible range of 520 nm to 680 nm due to the mixing of the blue pigment is the same as that of the color cathode ray tube having the two-layer coating 5 of the first to fourth configuration examples. It is slightly larger than the absorption. In the color cathode ray tube having the two-layer coating 5 of the fifth configuration example, the light transmission colors are a ′ = − 4 to +2, b ′ = +
5 to +10, and the light transmission colors a ′ and b ′ are slightly smaller than the same light transmission colors a ′ and b ′ of the color cathode-ray tube having the two-layer coating 5 of the fourth configuration example. The appearance of the panel section 1 face plate 1A is almost achromatic. Further, the color cathode ray tube having the two-layer coating 5 of the fifth configuration example has a surface sheet resistance value of about 300Ω / □ and a leakage electric field strength of ELEF of 0.1.
4 V / m, 0.4 V / m in VLEF, and T
Satisfies the CO standard sufficiently. In addition, the color cathode ray tube having the two-layer coating 5 of the fifth configuration example has a luminous reflectance of 0.6% and a luminous transmittance of 68%, and the body color black of the color cathode ray tube due to an anti-reflection effect. The uplift of the is canceled.

It should be noted that the second to fifth examples of the first to fifth configurations of the present embodiment.
In the layer coating 5, an example in which silver (Ag) fine particles are mixed in the conductive high refractive index first layer 14 has been described, but the present invention is directed to silver (Ag) fine particles in the conductive high refractive index first layer 14. The main component is not limited to silver (Ag), but other noble metals such as gold (Au) and ruthenium (R
u), rhodium (Rh), palladium (Pd), osmium (Os), iridium (Ir), platinum (Pt)
Or fine particles obtained by mixing two or more kinds of such noble metals.

Further, the second to fifth embodiments of the first to fifth embodiments of the present embodiment will be described.
In the layer coating 5, the low refractive index second layer 15 has been described as an example in which silicon dioxide (SiO ₂ ) is a main component. However, in the present invention, the silicon dioxide (S
Not limited to those using iO ₂ ), but silicon dioxide (S
Magnesium fluoride (MgF ₂ ) may be used in addition to iO ₂ ).

Further, the two-layer coating 5 of the first to fifth configuration examples
Is formed in the following procedure in the case of forming the first layer 14 on the face plate 1A, that is, the heating temperature at the time of drying the conductive high refractive index first layer 14 in steps S7 and S15. , Temperature at the time of drying the conductive high refractive index first layer 14 in step S18, step S9, step S12, step S
17. The firing temperature in step S20 is
Only typical temperatures are given. When the two-layered coating 5 of the first to fifth constitutional examples is applied to the face plate 1A according to the present invention, when the typical temperatures are used. It is not limited.

In this case, steps S7 and S1
The heating temperature at the time of drying the conductive high refractive index first layer 14 in FIG. 5 is 7 as described in parentheses in FIGS. 6 to 8.
The temperature at which the conductive high refractive index first layer 14 is dried in step S18 may be any temperature between 0 and 130 ° C., as shown in parentheses in FIG.
It can be any temperature between -60 ° C. Also,
The firing temperature in step S9, step S12, step S17, and step S20 may be any temperature between 160 and 175 ° C., as described in parentheses in FIGS.

In addition, in the two-layer coating 5 of the fifth configuration example in this embodiment, the case where the pigment added to the low refractive index second layer 15 is an anthraquinone blue pigment will be described as an example. However, the pigment added to the low refractive index second layer 15 in the present invention is not limited to the anthraquinone blue pigment,
Other pigments, for example, dioxaline-based pigments, phthalocyanine-based pigments or dyes, and silane coupling agents may be added.

In each of the above embodiments, after the temperature of the panel section 1, especially the face plate 1A surface is adjusted by a preheating step, a liquid in which fine metal particles are dispersed is applied on the face plate 1A in an application step. In a drying step, the liquid applied on the face plate 1A is dried to form the conductive high-refractive-index first layer 14 containing metal fine particles as a main component. Thereafter, a low-refractive-index second layer 15 is further formed by applying an alcohol solution of silicon alkoxide.
At this time, the alcohol solution of silicon alkoxide
It permeates into the gaps between the metal fine particles of the conductive high refractive index first layer 14 formed previously and reaches the surface of the face plate 1A. In the subsequent firing step, silicon oxide (including silicon hydroxide) generated by the reaction of the silicon alkoxide is used to bond the metal fine particles of the conductive high refractive index first layer 14 together, and to attach the metal fine particles to the face plate 1A.
And the adhesion between the metal fine particles and the low refractive index second layer 15 are strengthened.

Therefore, as the final form of the two-layer coating, the conductive first layer 14 of high refractive index is made of fine metal particles and silicon oxide as a binder, and the second layer 15 of low refractive index is made of silicon oxide. I have.

That is, the conductive high refractive index first layer 14 is formed as a layer consisting only of metal fine particles at the stage of applying the metal fine particle dispersion, and when the alcohol solution of silicon alkoxide is applied, Penetrates, and finally (after firing), a conductive high refractive index first layer 14 composed of metal fine particles and silicon oxide (including silicon hydroxide) is formed. The silicon oxide at this time functions as a binder, increases the adhesion between the metal fine particles (increases contact points), and improves the conductivity.
In addition, the gap between the metal fine particles is reduced and the gap is filled, which contributes to further increasing the refractive index of the conductive high refractive index first layer 14 and improves the antireflection effect.

According to the cathode ray tube having the electric field leakage prevention coating of this embodiment having such a configuration, as the metal fine particles used for the conductive high refractive index first layer 14, gold (Au) which is always in a chemically stable state is used. , Silver (Ag) or platinum (Pt), one or more kinds of noble metal elements are used, so that the surface sheet resistance of the conductive high refractive index first layer 14 is:
A noble metal element of the gold (Au), silver (Ag) or platinum (Pt) group used for the conductive high refractive index first layer 14, which can have a low resistance value of 1 KΩ / □ or less that can achieve the electric field leakage prevention function. In addition to the fact that one or more kinds of metal fine particles are in a chemically stable state at all times and are hardly oxidized, the conductive high refractive index first layer 1 can be used for a long time.
No deterioration of the surface sheet resistance of No. 4 occurs.

Further, according to the cathode ray tube having the electric field leakage prevention coating of this embodiment having such a configuration, the low refractive index second layer 15 is provided with a pigment or a dye which is complementary to the coloration of the body color of the cathode ray tube. In the case where a dye such as is added, the surface sheet resistance value of the conductive high refractive index first layer 14 is set to a low resistance value of 1 KΩ / □ or less which can achieve the electric field leakage prevention function, and the conductive property is maintained for a long time. High refractive index first layer 1
In addition to the fact that the surface sheet resistance of No. 4 does not deteriorate,
The coloring of the body color of the cathode ray tube can be complemented to make it achromatic.

[0095]

As described above, according to the first aspect of the present invention, the surface of the panel face plate of the cathode ray tube is
When depositing a two-layer coating composed of a conductive high refractive index first layer and a low refractive index second layer mainly composed of metal fine particles, the metal fine particles used for the conductive high refractive index first layer are always chemically Since at least one kind of fine metal particles of a noble metal element belonging to the genus of gold (Au), silver (Ag) or platinum (Pt) in a stable state is used, the surface sheet resistance of the first layer of the conductive high refractive index is used. The value can be not only a low resistance value of 1 KΩ / □ or less that can achieve the electric field leakage prevention function, but also gold (Au), silver (Ag) or platinum (Pt) used for the conductive high refractive index first layer. One or more kinds of fine metal particles among the noble metal elements belonging to the genus are always in a chemically stable state and are hardly oxidized. There is an effect that the resistance value does not deteriorate.

According to the third aspect of the present invention, the first high-refractive-index layer and the second low-refractive-index layer mainly composed of metal fine particles are formed on the surface of the face plate of the panel portion of the cathode ray tube. When depositing a two-layered film, the metal fine particles used for the conductive first layer having a high refractive index are noble metal elements belonging to the genus gold (Au), silver (Ag) or platinum (Pt), which are always in a chemically stable state. Since one or more kinds of metal fine particles are used, the surface sheet resistance of the conductive high refractive index first layer can be reduced to 1 KΩ / □ or less, which can achieve the electric field leakage prevention function. One or more kinds of fine metal particles among gold (Au), silver (Ag) or platinum (Pt) noble metal elements used for the conductive high refractive index first layer are always in a chemically stable state, All of them are difficult to oxidize, In addition to the effect that the surface sheet resistance of the first layer of the conductive high refractive index does not deteriorate, the pigment having a complementary color relationship to the coloring of the body color of the cathode ray tube is provided in the second layer of the low refractive index. Since a dye such as a dye or a dye is added, there is also an effect that the coloration of the body color of the cathode ray tube can be complemented and the color can be made achromatic.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a cathode ray tube having an electric field leakage prevention coating according to the present invention.

FIG. 2 is a cross-sectional configuration diagram showing a part of a first configuration example of a two-layer coating used in the color cathode ray tube of the present embodiment shown in FIG.

FIG. 3 is a cross-sectional configuration diagram showing a part of a second configuration example of the two-layer coating used in the color cathode ray tube of the present embodiment shown in FIG.

FIG. 4 is a sectional configuration diagram showing a part of a third configuration example of the two-layer coating used in the color cathode ray tube of the present embodiment shown in FIG.

FIG. 5 is a sectional configuration diagram showing a part of a fourth configuration example of the two-layer coating used in the color cathode ray tube of the present embodiment shown in FIG. 1;

FIG. 6 is a flowchart showing a forming procedure when the two-layer coating of the first configuration example is applied to the face plate.

FIG. 7 is a flowchart showing a forming procedure when a two-layer coating of the second configuration example is applied to a face plate.

FIG. 8 is a flowchart showing a forming procedure when a two-layer coating of the third configuration example is formed on a face plate.

FIG. 9 is a flowchart showing a forming procedure when a two-layer coating of the fourth configuration example is formed on a face plate.

FIG. 10 is a characteristic diagram showing a spectral transmittance of a color cathode ray tube having a two-layer coating of the first configuration example.

FIG. 11 is a characteristic diagram showing a spectral transmittance of a color cathode ray tube having a two-layer coating of the fourth configuration example.

FIG. 12 is a characteristic diagram showing a spectral transmittance of a color cathode ray tube having a two-layer coating of the fifth configuration example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Panel part 1A Face plate 2 Neck part 3 Funnel part 4 Fluorescent film 5 Two-layer coating 6 Shadow mask 7 Internal magnetic shield 8 Deflection yoke 9 Purity adjustment magnet 10 Center beam static convergence adjustment magnet 11 Side beam static convergence adjustment magnet 12 Electron Gun 13 Electron Beam 14 Conductive High Refractive Index First Layer 14A Convex 15 Low Refractive Index Second Layer 15A Low Refractive Index Third Layer

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Norikazu Uchiyama 3300 Hayano, Mobara-shi, Chiba Pref. Electronic Device Division, Hitachi, Ltd.

Claims (5)

[Claims] 1. A conductive high refractive index first layer containing metal fine particles as a main component and silicon dioxide (SiO ₂ ) or magnesium fluoride (MgF
₂ ) In a cathode ray tube having an electric-field leakage prevention coating to which a two-layer coating composed of a low-refractive-index second layer whose main component is ₂ ), the conductive high-refractive-index first layer includes gold (Au) as the metal fine particles. ), A cathode ray tube having an electric field leakage prevention coating, characterized in that at least one of noble metal elements belonging to the genus silver (Ag) or platinum (Pt) is used. 2. The method according to claim 1, wherein the conductive high refractive index first layer has a light absorbing property and a luminous transmittance in a range of 50 to 90%. A cathode ray tube having an electric field leakage prevention coating. 3. The electric field leakage according to claim 1, wherein the second layer having a low refractive index is added with a pigment such as a pigment or a dye, and has a selective absorption characteristic of a light wavelength. A cathode ray tube having a protective coating. 4. The two-layer coating is formed by applying a metal fine particle dispersion for forming a conductive high refractive index first layer on a surface of a face plate of a panel portion, and drying the coated surface to form the conductive high refractive index. A first layer is formed by adhesion, and the conductive high refractive index
An alcohol solution for forming the low refractive index second layer is applied on the layer, and the applied surface is baked at a temperature in the range of 160 to 175 ° C. to adhere and form the low refractive index second layer. A cathode ray tube having the electric field leakage prevention coating according to any one of claims 1 to 3. 5. The two-layer film is formed by applying a metal fine particle dispersion for forming a conductive high refractive index first layer to the surface of a face plate of a panel, and applying the coated surface to a temperature in the range of 70 to 130 ° C. By heating and drying, the conductive high refractive index first layer is adhered and formed, and an alcohol solution for forming a low refractive index second layer is applied on the conductive high refractive index first layer. The cathode ray tube having an electric field leakage prevention coating according to any one of claims 1 to 3, wherein the low-refractive-index second layer is adhered and formed by firing at a temperature in the range of 1 to 175 ° C.