JPS6055945B2 - Color picture tube manufacturing method and device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for manufacturing a color picture tube.

Generally, color picture tubes are manufactured as follows.

That is, a slurry of silica particles suspended in a photosensitive binder, usually a mixture of polyvinyl alcohol and ammonium dichromate, is applied to the panel to form a phosphorescent film.
An emulsion is applied to this fluorescent film, and then a metal back is applied. In order to decompose the polymer component in the fluorescent film thus obtained, the panel provided with this metal back is subjected to high temperature treatment. This is called panel baking.
Further, the baked panel and the funnel-shaped funnel are combined, and the two are fused together using low-melting glass. This process is called frit baking. Once this process has been completed, an electron gun is attached to the tube, and the tube is subjected to high temperature treatment again to exhaust the inside of the tube. This step is called an evacuation step, and is a step in which the polymer in the fluorescent film that remains undecomposed during panel baking and frit baking is decomposed, and the inside of the tube is brought into a high vacuum state. As described above, the conventional method of manufacturing a color picture tube requires a baking process three times, which requires a large amount of energy. Therefore, the present inventor attempted to simultaneously perform polymer decomposition in the fluorescent film and melting of the funnel using low melting point glass by combining a panel that has not been subjected to panel baking with a funnel.

However, in this case, the following problem was found. First, the decomposition of the polymer in the fluorescent film is insufficient, resulting in a large amount of organic residue in the fluorescent film. Second, the glass component of the low melting point glass is reduced, resulting in incomplete fusion of the panel and funnel.
This is due to the narrow neck of the funnel, which makes it difficult for the gas produced by the thermal decomposition of the polymer to flow out through the neck.The generated gas remains in the tube and oxygen is consumed in the thermal decomposition of the polymer, resulting in a lack of oxygen in the tube. Become. This prevents thermal decomposition of the polymer and reduces the low melting point glass. The present invention solves the above-mentioned disadvantages and provides a method and an apparatus for the same, in which thermal decomposition of organic matter and fusing of the panel and funnel are performed in the same baking furnace, thereby reducing energy consumption and shortening the manufacturing process. The purpose is to

The method and apparatus of the present invention will be explained below based on the illustrated embodiments.

FIG. 1 is a front view showing an embodiment of the apparatus used in the method of the present invention, and FIG. 2 is a plan view thereof. In FIGS. 1 and 2, 1 is a panel, 2 is a funnel, and a low-melting glass 3 is coated on the sealing surface thereof. 4 is a holder for holding the funnel 2; 5 is a spacer rotatably attached to the holder 4 with a pin 6; the tip 5a of the supporting portion thereof is formed in a tapered shape. 7 is a guide for positioning the panel 1 in the horizontal direction;
It is attached to the holder 4.

Further, although the details are not shown, the length of the guide 7 can be adjusted so that it can be adapted to a combination of panels 1 and funnels 2 of different sizes. Next, a case will be described in which thermal decomposition of an organic substance and fusion of a panel and a funnel are performed in the same baking furnace using an apparatus having such a configuration.

First, the funnel 2 whose funnel sealing surface has been coated with low melting point glass 3 is placed on the holder 4, and the panel 1 is placed on the spacer 5. The spacer 5 maintains the sealing surfaces of the panel 1 and funnel 2 at a predetermined distance. Also, if the number of spacers 5 is at least one, the purpose will be achieved; if there are too many spacers 5, the mechanism to remove them later will be complicated, so it is sufficient to use one spacer on each side, that is, four in total. The material for the part of the spacer 5 that the panel 1 comes into contact with is a material that does not damage the panel glass, such as Hemit.The spacer 5 holds the spacer 5 at a predetermined distance as described above, and then the panel 1 and the funnel are placed in a furnace. Oxygen is supplied from between 2 and gas generated by thermal decomposition of the polymer is discharged to the outside of the tube.

In this case, the distance between the panel 1 and the funnel 2 separated by the spacer 5 is related to the wind speed passing therebetween. If the wind speed in the furnace is fast, the interval may be narrow, and if the wind speed is slow, the interval may be wide. Experiments have shown that when the spacing is 2WL, it is sufficient to have a wind velocity of 10rr1/Sec in the furnace, and if the wind velocity is higher than that, it is difficult to maintain the temperature in the furnace. In addition, it was sufficient to have an interval of 30 mm and a wind speed of 1 m/Sec during the test. If this distance is wider, the spacer will only become thicker, but there will be no problem in supplying oxygen and discharging gas generated by thermal decomposition of the polymer to the outside of the tube. The temperature and time for heat-treating the panel 1 and the funnel 2 separated by the spacer 5 to decompose the polymer component in the fluorescent surface formed on the inner surface of the panel is the same as in the conventional case, at 380 to 410 degrees Celsius. 20 to 4 pieces is sufficient. When the thermal decomposition of the polymer component is completed, the spacer 5 is rotated and removed from the panel 1.

In this case, since the tip of the support part of the spacer 5 is formed in a tapered shape, the panel 1 descends quietly due to its own weight.
Contact the sealing surface of funnel 2. Also, at this time, the guide 7 prevents the panel 1 and the funnel 2 from being misaligned with each other. Thereafter, the panel 1 and the funnel 2 are fused together by the low melting point glass 3 applied to the sealing surface of the funnel 2.
The temperature and time at this time are 390 to 450, the same as before.
40 to 9 powder at ℃ is sufficient. Next, an experimental example conducted using the above method will be explained.

Low melting point glass 3 applied to the sealing surface of the panel 1 and the sealing surface of the funnel 2 held as shown in FIGS. 1 and 2
The distance between the two is set to 8wn. And like this panel l
The holder 4, which was a combination of the funnel 2 and the funnel 2, was placed on a conveyor and passed through the furnace. The temperature schedule at this time is
I did it as shown in the figure. First, at a heating rate of 10℃/Wn, 390
The temperature was raised to .degree. C. and maintained at this temperature for 3 cycles to thermally decompose the polymer component in the fluorescent film. Further, as shown in FIG. 4, a protrusion 8 acting on the spacer 5 was provided in advance in the furnace where the temperature inside the furnace was 410'C. As the conveyor moves in the direction of arrow A as shown in FIG. This causes the panel 1 to descend under its own weight. The conveyor is further advanced and moved through the furnace at 430° C. for 6 degrees to fuse the panel 1 and the funnel 2 with the low melting point glass 3. After this fusion has been completed, the temperature is lowered. In addition, the wind speed inside this furnace is 3 m by the side fan.
It was set to 1/Sec. The color picture tube manufactured in this way by decomposing the polymer component in the fluorescent film and fusing the panel and funnel using low-melting glass in the same furnace has undergone the conventional panel baking process and frit baking process. There was no difference in comparison. In addition, the energy consumed in the conventional baking process was reduced by about 15%, and the process time was reduced by about 20%. As is clear from the above description, by using the method and apparatus of the present invention, it is possible to reduce energy consumption and process time.

[Brief explanation of drawings]

Fig. 1 is a front partial sectional view of the apparatus used in the method of the present invention, Fig. 2 is a plan view thereof, Fig. 3 is a baking temperature schedule diagram, and Fig. 4 is a diagram showing the relationship between the protrusion fixed in the furnace and the holder. FIG. 3 is a plan view showing a relative positional relationship. 1...Panel, 2...Funnel, 3
...Low melting point glass, 4...Holder,
5...Spacer, 7...Guide, 8
······protrusion.

Claims (1)

[Claims] 1. In the baking process of a color picture tube, a predetermined distance is provided between the sealing surfaces of the panel and the funnel, the polymer components in the fluorescent film are first decomposed, and then the panel or funnel is baked under its own weight. 1. A method for manufacturing a color picture tube, which comprises lowering the tube to bring the sealing surfaces of the tubes into contact with each other, and fusing the tubes together using low-melting glass. 2 The distance between the sealing surface of the panel and funnel is 2 to 30 m.
2. The method for manufacturing a color picture tube according to claim 1, characterized in that: m. 3. The method for manufacturing a color picture tube according to claim 1, characterized in that the decomposition of the polymer component in the fluorescent film and the fusion of the panel and funnel are carried out in a furnace with a wind speed of 1 to 10 m/sec. . 4 A holder for placing one of the panel or the funnel, a spacer rotatably attached to the holder for placing the other of the panel or the funnel and providing a predetermined distance between the sealing surfaces of the two, and a spacer for placing the other of the panel or the funnel, and for the holder 1. A color picture tube manufacturing apparatus, comprising a guide for horizontal positioning of a panel or funnel placed on the attached spacer. 5. The method of manufacturing a color picture tube according to claim 4, wherein the number of spacers is 1 to 4. 6. The method of manufacturing a color picture tube according to claim 4 or 5, wherein the tip of the support portion of the spacer is formed into a tapered shape. 7 A holder for placing one of the panel or funnel, a spacer rotatably attached to this holder for placing the other of the panel or funnel and providing a predetermined distance between the sealing surfaces of the two, and a spacer for placing the other of the panel or funnel; The spacer is attached and serves as a guide for horizontal positioning of the panel or funnel placed on the spacer, and the spacer is rotated in a furnace where the polymer components in the fluorescent film are decomposed and the funnel is fused. A color picture tube manufacturing device characterized by having a protrusion for lowering a panel or funnel placed on a spacer by its own weight.