JPH11288665A - Manufacture of cathode-ray tube and cathode-ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cathode-ray tube manufacturing method whereby phosphor films on a faceplate are formed in a simplified way and a cathode-ray tube manufactured using the method. SOLUTION: A cathode-ray tube, having a faceplate 11 with an inner surface irradiated with a cathode ray beam, and having a first color phosphor film 13a, a second color phosphor film 13b, and a third color phosphor film 13c which are formed on the inner surface of the plate 11, has a first color filter layer 14a formed between the inner surface of the plate 11 and the first color phosphor film 13a, with the second color phosphor film 13b and the third color phosphor film 13c containing phosphors with pigments clinging thereto. Therefore, a protective resin film does not need to be formed during formation of each filter as is necessary if red, green, and blue layers are formed between a panel and the phosphor films, so that the number of manufacturing processes is greatly reduced and that manufacturing processes are simplified. Thus, not only costs are reduced but also the cathode-ray tube excellent in luminance and contrast characteristics can be manufactured.

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, and more particularly, to a method of manufacturing a cathode ray tube in which a phosphor film formed on a face plate is simplified and a phosphor film formed by the method. The invention relates to an improved cathode ray tube.

[0002]

2. Description of the Related Art As the industrial society is increasingly sophisticated, there is a demand for a cathode ray tube for display to have higher brightness and higher definition. In order to meet such demands, researches for improving the intensity of light emitted by an electron beam and reducing the reflectance due to external light are being actively conducted.

Hereinafter, the structure of a phosphor film of a conventional color cathode ray tube will be described.

On the inner surface of the face plate of the color cathode ray tube, black matrices are formed at regular intervals to absorb external light, and a fluorescent film which emits each color light upon collision with an electron beam is formed between the black matrices. Have been.

[0005] As a method for preventing a decrease in reflectance of the phosphor film itself due to external light and improving contrast and brightness, a method of coating a surface of a phosphor with a pigment, a method of coating red and red light between a panel and a phosphor film, and the like. Method for forming green and blue filter layers (U.S. Pat. No. 5,476,737)
And U.S. Pat. No. 5,179,318).

[0006] Among the above methods, the method of attaching a fine pigment to the surface of the phosphor is easy in the manufacturing process of the cathode ray tube, but has little effect of improving the contrast and the luminance characteristics, and has little effect on the fluorescent light at the time of exposure. There is a problem that the strength of the film is reduced.

On the other hand, the method of forming a filter layer has a remarkable effect of improving contrast and luminance characteristics.
There is a problem that the manufacturing process is very complicated and the cost is increased.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for manufacturing a cathode ray tube which simplifies and forms a fluorescent film on a face plate.

Another object of the present invention is to provide a cathode ray tube having improved luminance and contrast characteristics by the phosphor film manufactured by the above method.

[0010]

In order to achieve the above object, according to the present invention, an undercoating solution and a first color filter solution are applied to the inner surface of a face plate, dried, exposed, and exposed to light.
Forming a color filter layer, applying and drying a composition including the first color phosphor on the resultant having the first color filter layer formed thereon, and exposing and developing to form a first color phosphor layer. Forming a second color phosphor layer by applying and drying a pigment-attached second color phosphor on the resultant product having the first color phosphor layer formed thereon, and exposing and developing the second color phosphor layer; Coating and drying a pigment-attached third color phosphor on the resultant product having the color phosphor film formed thereon, and then exposing and developing to form a third color phosphor film for a cathode ray tube. Provided is a method for manufacturing a fluorescent film.

Another object of the present invention is to provide a cathode plate having an inner surface irradiated with a cathode ray beam, and a first, second and third color phosphor films formed on the inner surface of the plate. A first color filter layer formed between an inner surface of the plate and a first color phosphor film, wherein the second color and third color phosphor films are pigment-coated second color and third color phosphors; And a cathode ray tube characterized by including:

[0012]

According to the method of manufacturing a fluorescent film of the present invention, when a first color fluorescent film is formed, a first color filter layer is formed below the first color fluorescent film, and a second color and a third color fluorescent film are formed. Is used, a pigmented phosphor is used. In particular, the first color filter layer is preferably a blue filter layer,
The reason is as follows.

The wavelength that mainly affects the contrast is in the blue wavelength region. Therefore, adopting a blue filter and using a white phosphor to which no pigment is attached at the same time minimizes the decrease in brightness of light emitted from the phosphor and minimizes the amount of reflected light from external light, thereby improving contrast. It can be improved. Here, the transmittance of the blue filter layer is desirably 95% or more. By using the white phosphor on the filter layer in this manner, the aggregation of the phosphor is greatly reduced in the process of recovering the phosphor generated during the manufacturing process of the cathode ray tube, and the regeneration efficiency of the phosphor is greatly improved. Is obtained.

[0014] The pigment-attached phosphor is desirably used at the time of forming the green phosphor film and the red phosphor film, because the reflected light is suppressed and the effect of correcting the appearance is excellent.

In the pigment-attached phosphor, the pigment preferably has a particle size of 0.1 to 0.5 μm, and more preferably has a particle size of about 0.25 μm.
m is desirable. Preferably, the pigment-attached phosphor is a fine red pigment-attached red phosphor or a fine green pigment-attached green phosphor. Here, the red pigment and the green pigment are not particularly limited, but it is preferable to use a Fe ₂ O ₃ inorganic pigment as the red pigment and use a Co inorganic pigment as the green pigment.

Hereinafter, a method for manufacturing a fluorescent film according to the present invention will be described in detail with reference to FIG.

After mixing the undercoat liquid and the first color filter liquid, the composition is applied to the inner surface of the cathode ray tube face plate 11. Next, after drying the resultant, a predetermined area is exposed to selectively form a first color filter layer 14a at a position where the first color fluorescent film is formed.

The undercoat liquid is based on the total weight of the undercoat liquid.
0.1-5 wt% binder, 0.1-2.5 wt% photosensitizer, 0.1
〜1.0% by weight of surfactant and the balance of solvent. The first color filter solution is 5.0-15% by weight pigment, 0.1-5% by weight binder, 0.1-4.5% by weight photosensitizer, 0.1-1.0% by weight surfactant based on the total weight of the filter solution. Agent and its remaining content of solvent. Here, polyvinyl alcohol is used as a binder,
Dichromate is used as a photosensitive agent, and pure water is used as a solvent.

Next, a first color phosphor is applied and dried on the resultant product on which the first color filter layer 14a is formed.
Next, the first color fluorescent film 13a is exposed and developed.
Is formed. Reference numeral 12 in FIG. 1 indicates a black matrix.

Next, a second color phosphor with a second color pigment is coated and dried on the first color fluorescent film 13a, and is exposed and developed to form a second color fluorescent film 13b.

A third color pigment-attached third color phosphor is coated and dried on the resultant product on which the second color phosphor film 13b is formed, and is exposed and developed to form a third color phosphor film 13c. .

The first color filter layer is preferably a blue (B) filter layer which is more excellent in preventing a decrease in reflectance and luminance than green and red colors, and a second color phosphor having a second color pigment attached thereto. The third color phosphor with the third color pigment is preferably a green phosphor with a fine green pigment and a red phosphor with a fine red pigment, respectively, in terms of suppression of reflected light and correction of appearance.

[0023]Example 1  Blue pigment Co-blue in water, Pluronic L-92 (BASF
Company), sodium dichromate (sodium dichromate) and
Mixed with polyvinyl alcohol as adhesive and blue
A tar solution was prepared.

After the blue filter solution was applied to the inner surface of the cathode ray tube face plate and dried, a predetermined area was exposed to form a blue filter layer.

Subsequently, a blue phosphor ZnS: Ag, Al was applied and dried, and the resultant was exposed and developed to form a blue phosphor film.

Next, a fine red pigment Fe ₂ O ₃ -based inorganic pigment (Dainichi seika, particle size: 0.25) is formed on the blue fluorescent film.
μm) was coated and dried with a red phosphor Y ₂ O ₂ S: Eu, which was exposed and developed to form a red phosphor film.

Next, a green phosphor ZnS: Cu, Al having a fine green pigment Green 3320 (Dainichi seika, particle size: 0.2 μm) over-adhered on the resultant product having the red phosphor film formed thereon.
Was applied and dried, and exposed and developed to form a green fluorescent film.

[0028]Comparative Example 1  Red, green and blue with fine red, green and blue pigments attached
And blue phosphor (Y_TwoO_TwoS: Eu, ZnS: Cu, Al, Zns: Ag, A
l) each with water, polyvinyl alcohol, sodium dichromate
After mixing with Lium and PES, stir for about 5 hours, red, green
Color and blue phosphor slurries were produced.

After a green phosphor slurry was applied to the upper part of the cathode ray tube panel, it was exposed and developed to form a green phosphor film pattern.

The above process was repeated using a blue phosphor slurry and a red phosphor slurry instead of the green phosphor slurry to form blue and red phosphor film patterns.

[0031]Comparative Example 2  According to the usual method of forming green, blue and red filter layers
Thus, green, blue and red fluorescent films were formed.

That is, a green filter liquid was spin-coated on the cathode ray tube panel, dried, exposed and developed to form a green filter layer. Next, a composition containing a green phosphor was spin-coated on the resultant, dried, exposed, and developed to form a green microfilter phosphor layer. Next, a protective resin film was applied on the green fluorescent film.

The above process is repeated using a blue filter solution and a blue phosphor, and a red filter solution and a red phosphor instead of the green filter solution and the green phosphor to form blue and red microfilter phosphor layers sequentially. did.

[0034]Comparative Example 3  A red phosphor to which pigments having a particle size of about 1 μm are respectively attached.
Y_TwoO_TwoS: Eu, green phosphor ZnS: Cu, Al and blue phosphor Zn
S: Red, green, and blue fluorescent light using the usual method using Ag and Al
An optical film was formed.

The luminance, color reproduction range, contrast characteristics and characteristics of the manufacturing process of the cathode ray tube screen in the case of manufacturing according to the above-mentioned Example and Comparative Examples 1-3 were examined, and the results are shown in Table 1 below. Here, the color reproduction range is the colorimeter (Minolt
A company, MC-100) is used to indicate the color coordinates of each color, and the color coordinates of such color coordinates (color coordina
te) Determined by comparing the calculated values of the above areas with each other.

[0036]

[Table 1]

From Table 1, it can be seen that the brightness, color reproduction range, and contrast characteristics of the cathode ray tube having the phosphor film manufactured according to the example are superior to those of the comparative examples 1 and 3.

On the other hand, the brightness, color reproduction range and contrast characteristics of the screen of the cathode ray tube manufactured according to Comparative Example 2 are the most excellent, but as can be seen from Table 1, the number of steps is greatly increased and it is difficult to manufacture. Not only did the cost rise.

On the other hand, according to the embodiment, only the steps of coating, drying, exposing and developing the blue filter liquid for manufacturing the blue filter layer are added, so that the number of steps is significantly reduced as compared with the case of Comparative Example 2. did. In the case of Comparative Example 2, a protective resin film for preventing each filter layer from being melted out by the phosphor slurry of a different color must be formed without fail. Was unnecessary.

[0040]

According to the present invention, the protective resin film does not need to be formed when each filter is formed as compared with the case where the red, green and blue filter layers are formed, and the number of steps in the manufacturing process is greatly reduced. Now, the manufacturing process is simple, not only can the cost be reduced, but also a cathode ray tube having excellent brightness and contrast characteristics can be manufactured.

[Brief description of the drawings]

FIG. 1 is a view showing a structure of a fluorescent film for a cathode ray tube according to the present invention.

[Explanation of symbols]

 11 Face plate 12 Black matrix 13a First color fluorescent film 13b Second color fluorescent film 13c Third color fluorescent film 14a First color filter layer

Claims (8)

[Claims] 1. An undercoating solution and a first color filter solution are applied to an inner surface of a face plate, dried, exposed, and exposed to a first color.
Forming a color filter layer, applying and drying a composition including the first color phosphor on the resultant having the first color filter layer formed thereon, and exposing and developing to form a first color phosphor layer; Performing a pigment deposition on the resultant product on which the first color fluorescent film is formed.
After coating and drying the color phosphor, exposure and development
Forming a color phosphor layer, applying and drying a pigment-attached third color phosphor on the resultant product having the second color phosphor layer formed thereon, and exposing and developing to form a third color phosphor layer. And a method of manufacturing a cathode ray tube. 2. The method according to claim 1, wherein the first color filter layer is a blue filter layer, and the pigment-attached second color and third color phosphors are a fine red pigment-attached red phosphor and a fine green pigment-attached green phosphor, respectively. The method for manufacturing a cathode ray tube according to claim 1, wherein: 3. The method according to claim 1, wherein the first color phosphor is a white phosphor. 4. The method for manufacturing a cathode ray tube according to claim 1, wherein the diameter of the pigment in the pigments of the second color and the third color is 0.1 to 0.5 μm. 5. A cathode ray tube comprising: a face plate having an inner surface irradiated with a cathode ray beam; and first, second and third color fluorescent films formed on the inner surface of the plate. A first color filter layer formed between the inner surface and the first color phosphor layer, wherein the second and third color phosphor layers include pigment-attached second and third color phosphors; CRT. 6. The filter according to claim 5, wherein the filter layer is a blue filter layer, and the pigment-attached phosphor is a red pigment-attached red phosphor and a green pigment-attached green phosphor.
A cathode ray tube according to claim 1. 7. The cathode ray tube according to claim 5, wherein the diameter of the pigment is 0.1 to 0.5 μm in the pigments of the second color and the third color. 8. The cathode ray tube according to claim 5, wherein the first color phosphor film includes a white phosphor.