JP2001035371A - Method and device for drying phosphor screen for cathode-ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent unevenness of luminance, while preventing unevenness in drying the inner surface of a panel in a cathode-ray tube in the case of drying a phosphor screen for color cathode-ray tube, in which a heater device 4 heats the panel for color cathode-ray tube from a back surface side thereof. SOLUTION: A peripheral part of a panel 1 provided with a skirt 3 is heated stronger than a central part 2 thereof to evenly dry the panel 1. Specifically, the direction of a heater element 6 in relation to the central part 2 of the panel 1 is arranged nearly in parallel with the panel 1, and heater elements 6 in relation to the peripheral part provided with the skirt 3 are inclined at an acute angle with respect to the skirt 3, and the distance between the panel 1 and each heater element 6, in relation to the peripheral part of the panel 1 provided in the skirt 3, is formed shorter than a distance between the panel 1 and the heater element 6 corresponding to the central part 2 of the panel 1. This phosphor screen drying device having above structure is used for drying.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for drying a fluorescent screen of a cathode ray tube, in which a panel of the cathode ray tube is heated from the back side of the panel by a heater device, and an apparatus for drying a fluorescent screen of a cathode ray tube used in the method.

[0002]

2. Description of the Related Art A fluorescent screen of a color cathode ray tube is formed in the following order. 1. 1. applying a photoresist solution; 2. drying; exposure,
4. Development, 5. 5. Carbon (carbon for forming black stripes) applied; Drying, 7. 7. reversing agent application; 8. Development (completion of light absorption film formation); 9. Apply green phosphor slurry; Drying, 11. Exposure, 12. Development, 13. B
13. lue phosphor slurry application; Drying, 15. exposure,
16. Development, 17. 18. Red phosphor slurry application,
Drying, 19. Exposure, 20. Development (completion of phosphor luminescent film formation).

[0003] During a series of steps for producing the phosphor screen,
2.6.10.14.18. Is a drying step, and the drying in each of the drying steps is conventionally performed by the conventional method shown in FIG.
This was performed as shown in (A) and (B).

[0004] In the drawings, reference numeral 1 denotes a panel made of glass of a cathode ray tube, for example, a color cathode ray tube, 2 denotes a central portion of the inner surface of the panel 1, 3 denotes a skirt portion on a peripheral portion of the panel 1, and an inner surface of the panel 1. A fluorescent screen is formed on a portion inside the skirt portion 3, and drying is performed on the entire inner surface of the panel 1 and the outer peripheral surface of the skirt portion 3.

[0005] Reference numeral 4 denotes a heater device, which is provided with far-infrared ceramic heater elements 6, 6, ... on the surface of a gantry 5. Of the heater elements 6, 6, ...,
, The heater elements effective for heating the central portion 2 of the inner surface of the panel 1,
Are heater elements that are effective for heating the peripheral portion of the panel 1 where the skirt portion 3 is located. The circle shown by the broken line in FIG. 2 (A) indicates the position viewed from above the periphery of the panel 1, and the circle shown by the solid line is the panel 1
The position viewed from above the central part 2 is shown.

The drying process is performed by heating the panel 1 with the heater elements 6, 6,... For a predetermined time while rotating the panel 1 at a low speed to dry the inner surface thereof.

[0007]

According to the conventional apparatus for drying a fluorescent screen of a color cathode ray tube shown in FIG. 2, the central portion 2 of the inner surface of the panel 1 has heater elements 6, 6,. However, there is a problem in that drying is relatively rapid due to the effective heating from all directions, but the peripheral portion where the skirt portion 3 is present is not effectively heated, causing drying unevenness.

That is, the energy effective for drying from the far infrared heater element 6 is radiated from the heater element 6 at an angle of 180 °, and the amount of energy effective for drying the coating film is inversely proportional to the distance from the heater element 6. I do. Then, in consideration of the distance from the panel 1 to the heater element 6 near the center 2 on the inner surface of the panel 1, the number of heater elements 6 that give energy effective for drying is approximately 11 (
Heater element with, and heater element with).

On the other hand, the number of heater elements 6 effective for drying the peripheral portion (corner portion) of the panel 1 is nine (the heater element with and the heater element with). As described above, the number of heater elements 6 for effectively heating the central portion of panel 1 and the number of heater elements 6 for effectively heating the peripheral portion thereof are different, and the latter is two less than the former.
Therefore, the thermal energy that contributes to effective heating in the peripheral portion is smaller than that in the central portion.

In addition, the skirt 3 of the panel 1
Heater element 6 having a portion located outside panel 1
Since the heat rays (far infrared rays) from (the heater element 6 with) to the center of the panel 1 are blocked, the effective energy that contributes to the effective heating of the periphery of the panel 1 is further reduced. For these two reasons, there has been a problem that the progress of drying of the coating film tends to be delayed in the peripheral part more than in the central part, resulting in uneven drying.
Since the drying unevenness causes brightness unevenness of the cathode ray tube, the problem cannot be overlooked.

The present invention has been made in order to solve such a problem, and it is possible to dry the inner surface of a panel of a cathode ray tube without causing drying unevenness, thereby preventing the occurrence of luminance unevenness. The purpose is to be able to.

[0012]

According to a first aspect of the present invention, there is provided a method of drying a fluorescent screen of a cathode ray tube, wherein a panel is heated more strongly at a peripheral portion having a skirt than at a central portion to perform uniform drying. I do.

Therefore, according to the method for drying a fluorescent screen of a cathode ray tube according to the first aspect, the peripheral portion where the drying tends to be delayed is heated more strongly, so that the drying where the peripheral portion tends to be delayed than the central portion can be uniformly performed. Can be made to proceed. Therefore, uniform drying can be realized, and thus, luminance unevenness can be eliminated.

A fluorescent screen drying apparatus for a cathode ray tube according to claim 2 is
The orientation of the heater element with respect to the panel is inclined substantially in parallel for each heater element corresponding to the central portion of the panel, and at an angle forming an acute angle with respect to the skirt portion for the heater element corresponding to the peripheral portion having the skirt, and The distance of each heater element from the panel to the heater element corresponding to the peripheral portion having the skirt is shorter than that of the heater element corresponding to the central portion of the panel.

According to the apparatus for drying a fluorescent screen of a cathode ray tube according to the second aspect of the present invention, the heater element for effectively heating the peripheral portion is inclined at an acute angle to the skirt portion, and the distance from the panel is shortened. Therefore, the peripheral portion can be more effectively heated, and the peripheral portion, which has been conventionally delayed compared to the central portion, can be dried more quickly, and the drying unevenness can be reduced. Accordingly, the luminance unevenness can be reduced as compared with the related art.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The method for drying a fluorescent screen of a cathode ray tube according to the present invention is basically a method for drying a fluorescent screen of a cathode ray tube, wherein a panel of the cathode ray tube is heated from the back side of the panel by a heater. The uniform drying is performed by heating the peripheral portion having the skirt more strongly than the central portion, but this can be achieved by using the apparatus for drying the fluorescent screen of the cathode ray tube of the present invention.

The device for drying a phosphor screen of a cathode ray tube according to the present invention is a device for drying a phosphor screen of a cathode ray tube which heats a panel of the cathode ray tube from a back side of the panel by a heater provided with a plurality of heater elements. The direction of each heater element with respect to the panel is substantially parallel to each heater element corresponding to the center of the panel, and the angle forming an acute angle with respect to the skirt for heater elements corresponding to the peripheral part having the skirt. And the distance of each heater element to the panel is shorter in the heater element corresponding to the peripheral portion having the skirt than in each heater element corresponding to the center of the panel. The objects to be dried according to the present invention include not only color cathode ray tubes but also black and white cathode ray tubes. This is because drying is required during the production process of the black and white cathode ray tube.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments. 1A and 1B schematically show an embodiment of a cathode ray tube phosphor screen drying apparatus according to the present invention, wherein FIG. 1A is a plan view and FIG. 1B is a side view. In the drawings, 1 is a panel made of glass of a cathode ray tube, for example, a color cathode ray tube, 2 is a central portion of the inner surface of the panel 1, 3 is a skirt portion of a peripheral portion of the panel 1, and a skirt portion of an inner surface of the panel 1. A fluorescent screen is formed in a portion inside the panel 3, and drying is performed on the entire inner surface of the panel 1 and the outer peripheral surface of the skirt portion 3. 4a is a heater device which is directly on the surface of the gantry 5
Through the far infrared ceramic heater element 6, 6, ...
・ It is arranged. One of the heater elements 6, 6,...
Is provided directly on the surface of the gantry 5 as in the conventional case.

On the other hand, the heater elements 6, 6,..., Which are denoted by reference numerals, respectively, have the inclined tables 7, 7,. Is disposed so as to face obliquely outward through the center, and originally (conventionally) effectively heats the central portion 2, but in the present phosphor screen drying apparatus, it is directed obliquely outward as described above. ,
There is a tendency for the peripheral part to be overheated effectively, and
Accordingly, the distance to the panel 1 becomes shorter.

In addition, the heater elements 6, 6, which have portions which are protruded from the panel 1 when viewed from above and which are effective for heating the peripheral portion having the skirt portion 3,
Are arranged so as to face obliquely inward via the respective inclined platforms 7, 7,.... This heater element 6,
.. Are directed obliquely inward and are located closer to the panel 1 than before. Therefore, the heating of the peripheral portion becomes stronger than before.

The drying process is performed by heating the panel 1 with the heater elements 6, 6,... For a predetermined time while rotating the panel 1 at a low speed to dry the inner surface thereof.

According to the present apparatus, the heater element 6 for effectively heating the peripheral portion is inclined at an acute angle with respect to the skirt portion 3 and the distance from the panel 1 is shortened. Can be dried quickly, and the drying of the peripheral part, which was apt to be delayed compared to the central part, can be accelerated.
As a result, drying unevenness can be reduced. Accordingly, the luminance unevenness can be reduced as compared with the related art.

[0023]

According to the present invention, since the peripheral portion where the drying tends to be delayed can be heated more strongly, the drying where the peripheral portion tends to be delayed than the central portion can be uniformly advanced. Therefore, uniform drying can be realized, and thus, luminance unevenness can be eliminated.

[Brief description of the drawings]

FIGS. 1A and 1B show one embodiment of a method for drying a phosphor screen of a cathode ray tube according to the present invention, wherein FIG.
(B) is a side view.

FIGS. 2A and 2B show a conventional example of a method for drying a fluorescent screen of a cathode ray tube, wherein FIG. 2A is a plan view and FIG. 2B is a side view.

[Explanation of symbols]

1 ... panel, 2 ... central part of the inner surface of panel 1, 3
··· Skirt part, 4a ··· heater device, 5 ··· stand, 6 ··· heater element, 7 ··· slant base.

Claims (2)

[Claims] 1. A method for drying a fluorescent screen of a cathode ray tube, wherein a panel of the cathode ray tube is heated from a back side of the panel by a heater device, wherein the panel is heated more strongly at a peripheral portion having a skirt portion than at a central portion. And drying the phosphor screen uniformly. 2. A fluorescent screen drying apparatus for a cathode ray tube, wherein a panel of a cathode ray tube is heated from the back side of the panel by a heater device provided with a plurality of heater elements. The heater element corresponding to the central portion of the skirt portion is provided substantially in parallel, and the heater element corresponding to the peripheral portion having the skirt portion is provided at an angle that forms an acute angle with respect to the skirt portion. A fluorescent screen drying apparatus for a cathode ray tube, wherein a distance of a heater element corresponding to a peripheral portion having a skirt portion is shorter than a distance of each heater element corresponding to a central portion of the panel.