JPS6142837A - Manufacture of image display device - Google Patents

Abstract

PURPOSE:To reduce the time for manufacturing an image display device by performing thermal treatment which may become the cause of cracks only once by heating and fusing an upper and a lower non-airtight vacuum case where electrode groups are installed while the cases are placed in a vacuum container. CONSTITUTION:The fusing areas of an upper and a lower case 11a and 11b made of soft glass are coated with a frit 12 and the cases 11a and 11b are seperimposed upon each other so that gaps are formed between them by projections 12a. And, components such as electrodes are installed in the thus formed case. After several of thus obtained bodies are installed in a vacuum container 13, it is evacuated to 1X10<-5>Torr by means of a vacuum pump. Next, the vacuum cases 11 are heated with a heater 15 to 350 deg.C to heat the negative material and decompose it into an oxide while producing carbon dioxide gas which is then exhausted. After that, the vacuum cases 11 are heated to the operation point of the frit 12 to stick the upper and the lower cases 11a and 11b together, thereby making a plate image display device. Accordingly, it is possible to improve the manufacturing efficiency of image display devices by subjecting the vaccum case 11 containing components such as electrodes to thermal treatment such as fusion only once.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of manufacturing an image display device having a vacuum envelope.

Structure of the conventional example and its problems The flat panel image display device that is the object of the present invention utilizes thermionic emission. It has a configuration in which it converges, deflects, and accelerates the group to cause a desired pixel on the image display surface coated with a phosphor to emit light. FIG. 1 shows an external view of a vacuum envelope of a flat plate imaging device. A block diagram showing the manufacturing process of this image display device is shown in FIG.

The outline of the manufacturing process is as follows. First, a flat electrode group (not shown) is assembled (Fig. 2, 4), incorporated into the vacuum envelopes 1a and 1°b shown in Fig. 1, and heated in an electric furnace.
The sealing member 2 is melted and sealing 6 is performed. Here, the vacuum envelopes 1a and 1b are made of soft glass (thermal expansion coefficient: 100.5×1
0), and as the sealing member 2, a 95 to 100 x 10 x 7 piece is used to match thermal expansion. After the sealing process is completed, the exhaust pipe 3 is evacuated as shown in FIG. 2 using a vacuum pump, and heated to 300 to 350°C while maintaining the pressure at about 1d-5). The inside of the vacuum envelope is degassed (7). After the degassing step is completed, thermal decomposition 8 of the thermionic emission source inside the vacuum envelope 1 is performed. As the thermionic emission source, carbonates of barium, strontium, and calcium are thermally decomposed into oxides in vacuum. After the thermal decomposition is completed, the exhaust pipe 3 is heated to flash the sealing flap 9 and the getter, thereby completing the flat panel image display device.

In this flat panel image display device, in consideration of pressure resistance, the thickness of the glass constituting the vacuum envelope 1 is 10 mm, and since there is a large amount of contents, when heated in the sealing step 5 and the paking step 1o. If the rate of temperature increase is high, a temperature gradient will occur within the image display device, making it likely that cracks will occur. Therefore, the heating rate is slowed down to prevent cracking, but as a result, the sealing and paking processes take a long time, and the two processes take 20 hours, resulting in very low productivity. .

Furthermore, an exhaust pipe 3 is required to exhaust air during the paking process, and there is a high possibility that this exhaust pipe will be damaged during assembly, which may lead to a decrease in yield. Moreover, since the sealing process is performed in an oxidizing atmosphere, the contents such as electrodes are oxidized, and the electron beam may not be accurately controlled.

゛Object of the Invention The object of the present invention is to reduce the heat treatment process that causes cracking to one time, prevent the oxidation of the contents, eliminate the need for an exhaust pipe, and manufacture a flat panel image display device with high productivity. It is.

The structure of the invention is characterized in that heat treatment steps such as sealing are performed at once by housing and installing the unexploded #JI/i electrode group and heating the FC vacuum envelope in a vacuum.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. Third
The figure is a sectional view of a vacuum chamber used in an embodiment of the present invention. 11 is the vacuum envelope, and the enlarged exploded view before sealing is shown in 4th.
As shown in the figure. In Fig. 4, 11a and 11b are vacuum envelopes made of soft glass, the sealing part of which is coated with frit 12, and fired in advance at 350''C or higher for 30 minutes. Enclosure half body 11a
.

7 lift 12 in the corner part of 11b, the protrusion 1
2a is provided so that a gap opens when the vacuum envelopes 1a and 1b are stacked. This gap is.

When the vacuum chamber 13 in FIG. 3 is evacuated, the vacuum envelope 1
1 is also provided to maintain the same pressure as the vacuum chamber 13. In this example, as an example of the 7-lift 12, an amorphous frit with a softening point of 365°C and a working point of 436°C was used.

Components such as electrodes are assembled into the vacuum envelope 11 which has undergone the above treatment, and is set in the vacuum chamber 13, and the vacuum chamber 13 is evacuated to I.times.10-'' Torr using the vacuum pump 14.At this time, , the inside of the vacuum envelope 11 is the same as the X birth inside the vacuum chamber 13.This vacuum envelope 11 is heated using the heater 15.The heater 16 and the vacuum envelope 1
The positional relationship of 1 is 1.2 to 3 (close to about 111,
It has good heat uniformity. @ degree of vacuum envelope 11 is 350
When the temperature reaches ℃, the cathode material is heated and decomposed into oxides, and the carbon dioxide gas generated at that time is exhausted. This process is carried out before reaching the experimental point 370"Q of the 7 lifts 12. After the thermal decomposition of the cathode material is completed, the entire X envelope 11 is heated to the working point of 7 lifts 12, 435" Outer 8 vessels 11a and 11b
Glue and cool to room temperature.

The two steps described above, sealing, and baking, are now reduced to one, and the manufacturing time is halved to 10 hours. In addition, since the electrodes are sealed in a vacuum, the electrodes are not oxidized), and there is no effect on electron beam control. Furthermore, since no exhaust pipe is required, yields are improved, and
When incorporating a circuit as a receiver, it is no longer limited to the exhaust pipe.

Effects of the Invention As described above, the present invention eliminates the need to seal a vacuum envelope in a vacuum atmosphere, reduces the time conventionally spent on sealing and baking by half, and eliminates the need to provide an exhaust pipe. As a result, productivity has improved and costs have been reduced.

Furthermore, since oxidation of the electrodes constituting the image display device can be prevented, it has become possible to obtain good images.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a vacuum envelope of a conventional flat panel image display device, Fig. 2 is a process diagram of the manufacturing process of the image display device, and Fig. 3 is a sectional view of a vacuum chamber used in an embodiment of the present invention. , FIG. 4 is a perspective view of a vacuum envelope of a flat panel image display device according to an embodiment of the present invention. 11...Vacuum envelope, 12...7), 12a...Protrusion, 13...Vacuum chamber, 14...Vacuum pump, 16... Heater. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure=1

Claims (5)

[Claims] (1) An image display device characterized in that a vacuum envelope containing an electrode group is placed in a vacuum chamber in a non-airtight state, and the vacuum envelope is heated and sealed in a vacuum atmosphere. manufacturing method. (2) Evacuation is started before the vacuum envelope is heated and its sealing member starts to soften, and evacuation is continued until at least the sealing member is solidified. A method of manufacturing the image display device described above. (3) A method for manufacturing an image display device according to claim 1, characterized in that means for heating the vacuum envelope is provided inside the vacuum chamber. (4) A method for manufacturing an image display device according to claim 1, characterized in that the pressure in the vacuum chamber is set to 1×10^-^3 Torr or less. (5) An initial non-airtight state is obtained by providing one or more protrusions on the sealing member, and the protrusions are melted during heat sealing.
2. Method for manufacturing an image display device according to section 1.