JPH07272628A - Manufacture of color cathode-ray tube - Google Patents

Abstract

PURPOSE:To provide a color cathode-ray tube manufacturing method having the capability of reducing such improper water splash to a panel effective plane as appearing at the time of washing a panel pin, and reducing an amount of graphite adhering to the panel pin and a foreign substance in a tube. CONSTITUTION:A panel pin section 2 is coated with photo resist 3 at a process for forming a black matrix film on the inner surface 4 of the panel 1 of a color cathode-ray tube. Thereafter, the panel pin section 2 is exposed and etching solution is applied to the section 2, thereby separating graphite adhering to the panel pin section 2, together with the photo resist. Thus, no water is used for washing a panel pin and, therefore, improper water splash to a panel effective plane can be eliminated completely, thereby reducing an amount of distilled water consumption. Also, washing capability is enhanced, as the graphite of the panel pin section 2 is separated, together with the photo resist. Furthermore, an amount of a foreign substance in a tube can be reduced, resulting in the remarkable improvement of withstand voltage function for a spark in the tube or the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a color cathode ray tube, and more particularly to a method of cleaning an inner surface of a panel when forming a black matrix.

[0002]

2. Description of the Related Art The inner surface of a panel of a color cathode ray tube is provided with a black matrix as a light absorbing film for improving the contrast of an image, a phosphor layer having three kinds of emission colors, and further provided on the phosphor layer. It is made of an aluminum reflective film.

In the step of forming the black matrix film, after forming a photoresist film on the inner surface of the panel, a graphite solution is applied to the inner surface of the panel. At this time, since the graphite liquid is applied to the entire inner surface of the panel, the graphite also adheres to the surface of the panel pin for mounting the shadow mask provided on the inner wall of the panel.

A conventional black matrix forming process is shown in FIG.
And will be described accordingly. First, in order to remove dust and the like adhering to the panel inner surface 4, the panel inner surface 4 is washed with a hydrofluoric acid solution. Next, a photoresist (photosensitive resin liquid) 3 is spin-coated on the inner surface 4 of the panel. Next, the photoresist 3 is dried by a heater to form a photoresist film 3 '.
Next, a shadow mask is fitted to the panel and the light for blue position 6
1, the green position light 62 and the red position light 63 expose the inner surface of the panel in the arrow direction. Next, the unexposed area at the time of exposure is washed off by development. Next, slurry graphite 7 is spin-coated. Next, the panel pin is washed and the graphite 7 attached to the panel pin is dropped. Next, the graphite 7 applied to the panel inner surface 4 is dried to form a graphite film 7'on the panel inner surface. Next, panel inner surface 4
The photoresist is swollen by injecting an etching solution into the photoresist.
Next, the photoresist swelled by the development is washed off with a warm water spray to form a black matrix.

As a method for cleaning the panel pin, for example, a method disclosed in JP-A-62-219436, in which a sponge roller is brought into pressure contact with the panel pin to wipe off the coating liquid, is disclosed in JP-A-2-123633. There are methods such as cleaning with high-pressure hot water and cleaning with a rotating brush. When a sponge roller or brush is used, these deteriorate quickly and operation problems are likely to occur due to replacement. When water such as high-pressure hot water is used, there are problems of insufficient cleaning and poor water splash.

[0006]

The conventional panel pin cleaning method is mainly one in which graphite attached to the panel pin is cleaned with water, and there are problems of insufficient cleaning of the panel pin and splashing of water to the effective surface of the panel. Since the panel pin portion is washed before the graphite is dried, if the water splashes on the effective surface of the panel at this time, the graphite portion becomes thin only in that portion and the contrast becomes poor only in that portion. In addition, water splashes are difficult to detect by inspection immediately after the formation of the black matrix, and are likely to be found in a later process, which delays the response.

Further, since the spring of the shadow mask is fitted to the panel pin, if there is insufficient cleaning of the panel pin,
The graphite on the surface of the panel pin is scraped off and becomes conductive dust or foreign matter in the cathode ray tube, which causes sparks in the tube.

It is an object of the present invention to provide a method of manufacturing a color cathode ray tube in which water splashing defects are reduced and graphite attached to panel pins is reduced to reduce foreign substances in the tube.

[0009]

SUMMARY OF THE INVENTION According to the present invention, a photoresist is applied to a panel pin portion at the time of injecting a photoresist to the inner surface of the panel, and after drying, the panel pin portion is exposed in addition to the exposure to the effective surface of the panel, and the unexposed portion is exposed. Is washed with a developing solution, graphite is applied to the entire inner surface of the panel, and after drying, the panel pin portion is etched in addition to the etching of the panel effective surface, and the graphite attached to the panel pin portion is peeled off together with the photoresist. ing.

When the panel pin portion is exposed in addition to the exposure on the effective surface of the panel, quartz glass fiber is used as a means for transmitting the light for exposure.

[0011]

In the method of manufacturing a color cathode ray tube according to the present invention, the photoresist which has been applied to the panel pin portion in advance and dried is peeled together with the graphite by developing after etching, and the graphite attached to the panel pin portion is removed. By using quartz glass fiber when exposing the panel pin part, only the necessary part can be exposed. With such a method, the amount of graphite attached to the panel pin portion can be reduced, and foreign matter in the tube can be reduced. Since no water is used for cleaning the panel pins, it is possible to eliminate water splash defects and reduce the amount of pure water used.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a flow chart of steps applied to a method for cleaning panel pins of a color cathode ray tube according to the present invention, FIG. 2 is a sectional view showing an embodiment of a photoresist coating step, and FIG. 3 is an exposure step of panel pin portions. FIG. 4 is a cross-sectional view showing an embodiment of the present invention, and FIG. 4 is a cross-sectional view showing an embodiment of the etching liquid application step. A description will be given below along with the flowchart of FIG. 1 based on the drawings.

First, the panel inner surface 4 is washed with a hydrofluoric acid solution in order to remove dust and the like adhering to the panel inner surface 4.

Next, photoresist (photosensitive resin liquid containing polyvinyl alcohol and ammonium dichromate)
3 is applied to the inner surface 4 of the panel. At this time, the photoresist 3 is also applied to the panel pin portion 2 so that the photoresist film 3'is formed. As shown in FIG. 2, the panel 1 is supported and rotated by a panel support portion (not shown), and the photoresist 3 is applied to the entire inner surface 4 of the panel by the centrifugal force thereof.
Has been applied.

Next, the photoresist 3 is dried by a heater to form a photoresist film 3 '.

Next, the panel pin 2 is connected to the panel pin light 60.
To expose in the direction of the arrow. As shown in FIG. 3, by using the quartz glass fiber 5 as a light transmitting means for exposing the panel pin portion 2 with the light of the light source 6, only the panel pin portion 2 is exposed without leaking the light to the outside. be able to.

Next, a shadow mask is fitted on the panel, and the inner surface of the panel is exposed in the direction of the arrow with light 61 for blue position, light 62 for green position, and light 63 for red position.

Next, the unexposed area at the time of exposure is washed off by development.

Then, slurry-like graphite 7 is spin-coated on the entire inner surface 4 of the panel. Therefore, the graphite 7 is attached to the panel pin portion 2 as well.

Next, the graphite 7 applied to the inner surface 4 of the panel is dried to form a graphite film 7'on the inner surface of the panel.

Next, an etching solution is injected into the panel inner surface 4 to swell the photoresist film 3 '. As shown in FIG. 4, the etching liquid 8 is applied to the panel pin portion 2 in addition to the panel inner surface.

Next, the photoresist 3'swelled by the development is washed off together with the graphite film 7'with a hot water spray to form a black matrix. Since the photoresist is peeled off, all the foreign matters adhering to the photoresist film are removed, and the graphite adhering to the panel pin portion can also be removed.

Although the panel pin exposure and the panel surface exposure are performed in this order in FIG. 1, the panel surface exposure and the panel pin exposure may be performed in that order.

[0024]

According to the present invention, since the panel pin cleaning is peeled by the exposure technique instead of the water cleaning, it is not necessary to use the water for the panel pin cleaning, and the defective water splashing on the panel surface can be eliminated, and the pure water is used. The amount can be reduced. Further, since the graphite of the panel pin portion is peeled off together with the photoresist, the cleaning ability is higher than that of the conventional water cleaning, foreign matter in the pipe is reduced, and as a result, the withstand voltage performance such as sparks in the pipe can be remarkably improved.

[Brief description of drawings]

FIG. 1 is a flow chart of a black matrix forming process according to the present invention.

FIG. 2 is a cross-sectional view showing an example of photoresist coating.

FIG. 3 is a cross-sectional view showing an example of panel pin portion exposure.

FIG. 4 is a cross-sectional view showing an example of application of an etching solution.

FIG. 5 is a flowchart of a conventional black matrix forming process.

[Explanation of symbols]

 1 panel 2 panel pin section 3 photoresist 3'photoresist film 4 panel inner surface 5 quartz glass fiber 6 light source for exposure 60 light for panel pin 61 light for green position 62 light for blue position 63 light for red position 7 graphite 7'graphite film 8 etching solution

Claims (2)

[Claims] 1. A method of manufacturing a color cathode ray tube comprising a step of forming a black matrix film on an inner surface of a panel,
Applying a photoresist to the panel pin part, exposing this panel pin part, applying graphite slurry to the inner surface of the panel, then applying an etching solution to the panel pin part, and peeling the graphite adhering to the panel pin part together with the photoresist. A method for manufacturing a characteristic color cathode ray tube. 2. The method of manufacturing a color cathode ray tube according to claim 1, wherein a quartz glass fiber is used as a light transmitting means in the exposure of the panel pin portion.