JPH09293454A - Manufacture of cathode-ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the process time so as to enhance production efficiency and reduce consumed energy during processes by irradiating a panel with a laser beam in a panel baking process during the cathode-ray tube manufacturing, process followed by a heat treatment. SOLUTION: An organic matter 7 contained in slurry of a fluorescent film 6 formed at the inner face of a panel 5 is first burnt in a heat treatment, followed by heating and decomposing in a panel baking process. An infrared laser 9 irradiates the entire face of the panel 5, in which an aluminum deposited film 8 is formed on the resultant film 6 via an organic suspension 7, followed by heating at a predetermined temperature. In the dedusting atmosphere, it is possible to prevent foreign matters from adhering to the films 6, 8 formed on the panel 5. Consequently, the foreign matters adhering to the inside of the panel due to machining or a shock during a cathode-ray tube manufacturing process can be peeled off, thereby preventing a hole of a shadow mask from clogging. After light irradiation by the laser 9, a process for cooling the panel 5 is performed in the atmosphere of nitrogen gas or dry inactive gas, thus reducing unnecessary gas to be adsorbed by the panel 5.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for manufacturing a cathode ray tube.

[0002]

2. Description of the Related Art Generally, a cathode ray tube manufacturing method is performed in the order of manufacturing steps shown in FIG. FIG. 8 shows a sectional view of the cathode ray tube. First, in the fluorescent film / aluminum film forming step 1, the fluorescent film 6 and the aluminum vapor deposition film 8 are formed on the inner surface of the panel 5 which constitutes the envelope portion 10 (hereinafter referred to as a bulb) of the cathode ray tube. In this case, in order to form the aluminum vapor deposition film 8 that is as smooth as possible, the film formation of the organic suspension 7 is performed after forming the fluorescent film 6.

Next, a heat treatment step 2 is performed. First, a panel baking step (2) for burning and decomposing the organic substance 7 such as polyvinyl alcohol in the slurry of the fluorescent film 6 formed on the inner surface of the panel 5 or the lacquer in filming (2)
1) is performed, and then a frit baking step (22) of welding and joining both the panel 5 and the funnel portion 11 with frit glass is performed. Then the electron gun 12 on the neck
The stem sealing step (23) for mounting and sealing the valve and the vacuum exhausting step (24) for vacuuming the inside of the valve are sequentially performed. Then, the aging step 3 and the reinforcing step 4 are performed to complete the cathode ray tube.

In the heat treatment steps 2 (21) and (22), if the respective steps are performed independently, the temperature of the valve is raised and lowered repeatedly, resulting in a longer process time as a whole and a larger energy consumption. Since the cost increases, a method of carrying out at once is also proposed (Japanese Patent Laid-Open No. 2-79323).

[0005]

In the conventional panel baking (21) in the heat treatment step, when the panel portion made of glass is heated to the decomposition temperature of organic substances, the panel portion is not heated during the heating process. Since cracks and the like occur when the temperature distribution occurs, it was necessary to gradually heat and gradually cool. Therefore, a long heating furnace is required, a long processing time is required, energy consumption for heating is large, and it is uneconomical. Also, considering the production efficiency, the processing time is long, so it is not possible to secure a sufficient holding time at the decomposition temperature of organic matter, and the organic matter that could not be decomposed remains in the fluorescent film, and the fluorescent film is irradiated by the electron beam. Was discolored and the brightness was lowered.

[0006]

In order to solve the above-mentioned problems, in a panel baking process (21) in a cathode ray tube manufacturing process, a fluorescent film is applied and film-forming of an organic suspension is performed to perform aluminum vapor deposition. The panel portion on which the film is formed is irradiated with laser light to perform heat treatment.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A cathode ray tube manufacturing process for explaining an embodiment of the present invention is shown in FIG. First, in the fluorescent film / aluminum film forming step 1, the fluorescent film 6 is formed on the inner surface of the panel 5 constituting the cathode ray tube, and then the aluminum vapor deposition film 8 is formed on the fluorescent film 6. In this case, in order to form the aluminum vapor deposition film 8 that is as smooth as possible, the film formation of the organic suspension 7 is performed after forming the fluorescent film 6.

Next, the heat treatment step 2 of the valve 10 is performed.

In the heat treatment step 2, first, the purpose is to heat and decompose organic substances 7 such as polyvinyl alcohol in the slurry of the fluorescent film 6 formed on the inner surface of the panel portion 5 and lacquer in filming by heating them. Panel baking process (2
Perform 1). As shown in FIG. 3, the fluorescent film 6 is formed,
An infrared laser beam 9, for example, a YAG laser beam or a carbon dioxide laser beam is applied to the entire surface of the panel 5 on which the aluminum vapor deposition film 8 is formed on the fluorescent film 6 with the organic suspension 7 interposed therebetween, and 430 to 4
Heat at 50 ° C. At this time, if it is performed in a dust-free atmosphere, it is possible to prevent foreign matter from adhering to the fluorescent film 6, the aluminum vapor deposition film 8 and the like of the panel section 5. Therefore, it is possible to prevent the foreign matter attached to the inside of the panel 5 from being peeled off and clogging the holes of the shadow mask 13 due to the processing during the manufacturing process of the cathode ray tube and the impact accompanying the processing. In the process of cooling the panel 5 after irradiation with the laser beam 9, the unnecessary gas (mainly water) adsorbed on the panel 5 is reduced by performing the process in a nitrogen gas, inert gas, dry nitrogen gas, or dry inert gas atmosphere. be able to.

After that, a frit baking step (22) of welding and joining both the panel portion 5 and the funnel portion 11 with frit glass, a stem sealing step 23 of mounting and sealing the electron gun 12 on the neck portion, and the inside of the valve. The evacuation process (23) for evacuating is performed sequentially.

Then, the aging step 3 and the reinforcing step 4 are performed to complete the cathode ray tube.

FIG. 4, FIG. 5, and FIG. 6 show another method of irradiating the panel portion with laser light. As described in the embodiment of the present invention, the fluorescent film 6 and the aluminum vapor deposition film 8 are formed on the inner surface of the panel portion, and the film of the organic suspension 7 is formed between the fluorescent film 6 and the aluminum vapor deposition film 8. The application is being done. As shown in FIG. 4, the panel 5 is irradiated with infrared laser light 9, for example, YAG laser light or carbon dioxide gas laser light while scanning the entire surface, and is heated at 430 to 450 ° C. Although FIG. 5 shows the case where the number of laser beams 9 is 6, a plurality of laser beams 9 are used, and irradiation is performed while scanning at several points on the panel portion. Further, as shown in FIG. 6, according to the size of the panel 5, the laser beams 9 are arranged in parallel and in series, and the laser beam 9 is squeezed to an appropriate size for irradiation.

The direction of irradiating the laser light is not limited to the front surface of the panel portion, but may be the side surface, the rear surface, and the multi-direction irradiation at the same time.

Another embodiment of the present invention is shown below in FIG.
As described in the embodiment of the present invention, the fluorescent film 6 and the aluminum vapor deposition film 8 are formed on the inner surface of the panel portion, and the film of the organic suspension 7 is formed between the fluorescent film 6 and the aluminum vapor deposition film 8. The application is being done. Next, the organic substance 7 such as polyvinyl alcohol in the slurry of the fluorescent film 6 formed on the inner surface of the panel 5 or lacquer in filming is baked to decompose them by heating. At this time, as shown in FIG. 7, the fluorescent film 6 is formed, and the aluminum deposition film 8 is formed on the fluorescent film 6 with the organic suspension 7 interposed therebetween.
The panel 5 on which is formed is irradiated with microwaves 14 to perform heat treatment. At this time, if the operation is performed in a dust-free atmosphere, foreign matter can be prevented from adhering to the inner surface of the panel. Further, at the time of cooling, it is carried out in an atmosphere of nitrogen gas, inert gas, dry nitrogen gas, and dry inert gas to reduce the adsorption of unnecessary gas onto the inner surface of the panel section.

After that, the cathode ray tube is completed according to FIG.

[0016]

According to the present invention, since the entire panel portion can be instantly heated to the decomposition temperature of the organic substance by using the laser beam, the heating process takes almost no time, and the desired treatment can be carried out in a short time. Increases production efficiency. Furthermore, the energy consumption of this processing step can be greatly reduced.
In addition, a large heating furnace is not needed, and the equipment can be reduced.

Further, since the temperature rising time to the decomposition temperature of the organic matter in the panel portion can be shortened, the irradiation time of the laser beam is sufficiently taken and the undecomposed organic matter remaining in the fluorescent film is eliminated, whereby the electron beam irradiation is performed. Discoloration of the fluorescent film is eliminated, and it is possible to prevent a decrease in brightness due to this.

[Brief description of drawings]

FIG. 1 is a flowchart showing a manufacturing process of a conventional cathode ray tube.

FIG. 2 is a flowchart showing a manufacturing process of a cathode ray tube according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a method of irradiating a panel portion with laser light according to an embodiment of the present invention.

FIG. 4 is an explanatory view showing another method of irradiating the panel portion with laser light according to the present invention.

FIG. 5 is an explanatory view showing another method of irradiating the panel section with laser light according to the present invention.

FIG. 6 is an explanatory view showing another method of irradiating the panel portion with laser light according to the present invention.

FIG. 7 is an explanatory view showing a method of irradiating a panel portion with microwaves according to another embodiment of the present invention.

FIG. 8 is a cross-sectional view of a cathode ray tube.

[Explanation of symbols]

5 ... Panel, 6 ... Fluorescent film, 7 ... Organic material, 8 ... Aluminum vapor deposition film, 9 ... Laser light, 10 ... Bulb, 11 ... Funnel part, 12 ... Electron gun, 13 ... Shadow mask, 14 ... Microwave, 15 ... Laser beam scanning line, 16 ... Laser beam spot diameter.

Claims (1)

[Claims] 1. A color cathode ray tube having a heat treatment step for removing an organic substance applied due to vapor deposition of the smooth aluminum film when a fluorescent film and an aluminum film are formed on a panel portion constituting the cathode ray tube. A method of manufacturing a cathode ray tube, which comprises irradiating a laser beam to perform a heat treatment.