JP3132316B2 - Method for forming phosphor screen of color 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 a method for forming a phosphor screen of a color picture tube, and more particularly to a method suitable for forming an opening having a predetermined hole diameter distribution for limiting a light emitting region of a phosphor in a black matrix film. .

[0002]

2. Description of the Related Art Generally, a phosphor screen of a so-called black matrix type color cathode ray tube in which a light emitting region of a phosphor is limited by a graphite film as a light absorbing material is disclosed in Japanese Patent Laid-Open No. 5-8 / 1993.
This is performed by a process as disclosed in Japanese Patent No. 9775. That is, as shown in FIG.
Is coated with a photoresist solution containing, for example, polyvinylpyrrolidone and a bisazide compound as main components, dried to form a photoresist layer 2, and then exposed by mounting a shadow mask (not shown). After the exposure, as shown in FIG. 3B, the photoresist layer 2 is developed to form a dot-shaped resist pattern 3 baked through an electron beam passage hole of a shadow mask. Then, as shown in FIG. 3C, a graphite suspension is applied on the resist pattern 3 and dried to form a graphite film 4, and then, for example, an etching solution such as a hydrogen peroxide solution is applied. Pour into the inside of panel 1,
Act on resist pattern 3 to decompose. further,
When the decomposed resist pattern 3 is removed by strong spray pressure, washed with water and dried, a black matrix film 6 having a desired opening 5 is formed as shown in FIG. The three-color phosphor layers B, G, and R are embedded in predetermined positions of the opening 5 to form a phosphor screen.

However, the size of the opening of the black matrix film fluctuates due to factors such as the thickness distribution of the photoresist layer, the transmittance distribution of the light control filter, and the like. On the other hand, since the electron beam spot spreads in the peripheral portion due to deflection, it is necessary to enlarge the opening to increase the area of the phosphor dot. As described above, in order to form the opening diameter of the black matrix film in a predetermined size distribution, the hole diameter distribution of the shadow mask is changed, the transmittance distribution of the light control filter is changed, and the hot air is exposed before exposure. It was necessary to adjust the sensitivity of the photoresist film by blowing cold or cold air onto the photoresist film, or to adjust the photoresist film thickness distribution.

[0004]

However, changing the hole diameter distribution of the shadow mask or the transmittance distribution of the light control filter requires changing the original shadow mask plate and the light control filter, which is very difficult in practice. Adjustment of the photoresist film thickness distribution causes problems such as phosphor remaining, holes dropping, and film unevenness, and sensitivity adjustment of the photoresist film causes problems such as adhesion of foreign substances. The purpose of the present invention is
In order to solve the above problems, the drying state is adjusted in the drying step of the graphite film to change the permeability of the etching liquid into the graphite film at an arbitrary position, and the size of the opening of the black matrix film is determined. It is an object of the present invention to provide a method for forming a fluorescent screen of a color cathode ray tube, which adjusts the distribution of the phosphors.

[0005]

According to the present invention, there is provided a glass panel having an inner surface coated with a photoresist, exposed through a shadow mask to form a resist pattern, coated with a light-absorbing substance, dried, and then dried. A method for forming a fluorescent screen of a color cathode ray tube, comprising removing a pattern and forming a light absorbing material film having an opening in a phosphor disposing portion, wherein the drying state of the light absorbing material film is controlled to form the light absorbing material film. The present invention provides a method for forming a fluorescent screen of a color cathode-ray tube, characterized by adjusting the shape and size of the portion. Also, the method for controlling the dry state is performed by adjusting the arrangement pattern of heaters for drying in which the phosphor screen forming surface is divided into a plurality of blocks and the output of each block, and the method for controlling the dry state includes a plurality of hot air jets. It is desirable to perform this by adjusting the arrangement pattern of the nozzles and the hot air temperature for each nozzle.

[0006]

Normally, if the dry state of the light-absorbing material film is perfect, the etching solution for the resist pattern does not penetrate into the light-absorbing material film, so that only the resist pattern is removed and an opening having the same dimensions as the resist pattern is formed. If the drying state is insufficient, the etching solution of the resist pattern penetrates into the light absorbing material film, and a part of the light absorbing material film in contact with the resist pattern is also removed. A part is formed. Therefore, by adjusting the dry state of the light-absorbing material film depending on the location, a light-absorbing material film having an arbitrary aperture diameter distribution can be formed. If the drying output is adjusted by changing the arrangement pattern of the heater for drying and the hot air jet nozzle for drying by dividing the central block and the peripheral block of the phosphor screen, the density is reduced by the deflection of the electron beam. By increasing the diameter of the opening in the peripheral portion, it is possible to easily form a fluorescent screen of a color cathode ray tube in which the luminous intensity is uniform over the entire fluorescent screen.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. The same parts as those in the conventional example are denoted by the same reference numerals, and description thereof will be omitted. As shown in FIG. 1 (a), the method for forming a phosphor screen of a color cathode ray tube according to the present invention, as shown in FIG. 1 (a), forms a photoresist solution containing, for example, polyvinylpyrrolidone and a bisazide compound as main components on the inner surface of panel 1. Is applied and dried to form a photoresist layer 2 and then exposed by mounting a shadow mask (not shown). After completion of the exposure, as shown in FIG. 1B, the photoresist layer 2 is developed to form a dot-shaped resist pattern 3 baked through an electron beam passage hole of a shadow mask. Then, as shown in FIG. 1 (c), a graphite suspension is applied on the resist pattern 3 and, for example, a drying heater 9 divided into a central portion 7 and a peripheral portion 8 on the inner surface of the panel 1. , 9a to adjust the output of the central part 7
After completely drying the peripheral portion 8 by controlling the drying state slightly incompletely to form the graphite film 10, an etching solution such as a hydrogen peroxide solution is injected into the inner surface of the panel 1 to form a resist pattern. 3 to cause decomposition. Further, the decomposed resist pattern 3 is removed by strong spray pressure, washed with water and dried. Then, as shown in FIG. 1D, an opening 11 corresponding to the resist pattern is formed in the central portion 7 where the graphite film 10 is completely dried.
A part of the graphite film in contact with the resist pattern is removed by the infiltration of the etchant in the incomplete peripheral portion 8 of the graphite film 10 in a dry state, and a black matrix film 13 having an opening 12 slightly larger than the resist pattern is formed. You. If the phosphor screen is formed by embedding the three-color phosphor layers B, G, and R at predetermined positions of the openings 11 and 12, the peripheral phosphor dots where the electron beam density is reduced can be enlarged. A fluorescent screen having uniform luminance characteristics over the entire surface can be formed.

The method for forming a fluorescent screen of a color cathode ray tube according to the second embodiment of the present invention uses a hot air jet nozzle as a drying means as shown in FIG. Injection nozzle 14 and hot air injection nozzle 14a in peripheral portion 8
The drying state is controlled by adjusting the warm air temperature and air volume. According to this embodiment, effects similar to those of the first embodiment can be obtained.

Although the method of controlling the size and shape distribution of the openings of the black matrix film in the central part and the peripheral part of the phosphor screen by controlling the dry state has been described above, the present invention is not limited to this example. In addition, the drying state is controlled by further subdividing the arrangement of the drying means such as a drying heater and a hot air injection nozzle, or by adjusting the output to correct the hole diameter distribution of the shadow mask and the transmitted light amount distribution of the light control filter. Can also be implemented.

[0010]

According to the present invention, it is possible to form a light absorbing material film having an arbitrary aperture diameter distribution by adjusting the dry state of the light absorbing material film depending on the location. By adjusting the drying output by changing the arrangement pattern of the heater for drying and the hot air jet nozzle for drying by dividing into the peripheral block, the diameter of the opening in the peripheral part where the density decreases due to the deflection of the electron beam can be increased. Thus, the fluorescent screen of the color cathode-ray tube in which the luminous intensity over the entire fluorescent screen is uniform can be easily formed.

[Brief description of the drawings]

FIGS. 1A to 1D are explanatory views of a fluorescent screen forming process of a color cathode ray tube according to an embodiment of the present invention.

FIG. 2 is a layout view of a dry spray nozzle according to a second embodiment of the present invention.

FIG. 3 is an explanatory view of a conventional phosphor screen forming process of a color cathode ray tube.

Claims (3)

(57) [Claims] 1. A glass panel having an inner surface coated with a photoresist is exposed through a shadow mask to form a resist pattern, coated with a light-absorbing substance, dried, and then the resist pattern is removed. A method of forming a phosphor screen of a color cathode ray tube comprising a step of forming a light absorbing material film having an opening in a portion, wherein the dry state of the light absorbing material is completely in the center of the panel and slightly incomplete in the peripheral portion. controlling the shape of the opening so that the diameter of the opening at the periphery is at the center.
A method for forming a fluorescent screen of a color cathode ray tube, wherein the diameter is adjusted to be larger than the diameter of the opening . 2. A fluorescent screen forming method for a color cathode ray tube according to claim 1, wherein said method of controlling the drying state is performed by adjusting an arrangement pattern of a drying heater divided into a plurality of blocks and an output of each block. Method. 3. The method for forming a fluorescent screen of a color cathode ray tube according to claim 1, wherein the method of controlling the drying state is performed by an arrangement pattern of a plurality of hot air jet nozzles and a hot air temperature adjustment for each nozzle. .