JPH01258339A - Manufacture of discharge gap constituting body and gas discharge display device - Google Patents

Abstract

PURPOSE:To obtain a high quality but less expensive gas discharge display device by fabricating a discharge gap constituting body in such a way that a mold is made by the precision machining of a graphite plate, fine ceramic powder is filled in the gap thereof and the mold is released after heating, dissolving and cooling the powder. CONSTITUTION:Graphite plates 11, each having a thickness equal to the length of one side of a discharge cell 1, are laid on top of each other and grooved, using a wire processing machine 12 and the like, except for the width of other sides. Thereafter, the plates 11 are overhauled and a mold for a discharge gap constituting body 2 is formed, using a spacer and the like. The mold so made is housed in a frame 13 having a bottom and the fine powder 14 of ceramics such as glass is filled in a gap. Then, the powder is heated, dissolved and then cooled in a oxygen free environment, thereby obtaining a glass block 15. Furthermore, the glass block 15 is burnt in an oxygen and the graphite is thereby removed. Thereafter, the block 15 is sliced to the length of the discharge cell 1 by means of a wire saw 16 and the like, thereby obtaining the constituting body 2. A fluorescent material T is applied to the wall surface of the body 2 and a xenon gas is sealed in the cell 1 bonded with a glass display board 4 having an anode 5 and a glass substrate 6 with a cathode 5, and a gas discharge display device can be thereby fabricated with high productivity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a gas discharge display device that utilizes light emission from ionized gas, and particularly relates to a full-color gas discharge display device that has a large screen, high brightness, and high resolution. .

[Conventional technology]

In a gas discharge display device, a sealed gas is ionized in a discharge space, and information is displayed by the light emission of the ionized gas itself or by the fluorescence generated when a phosphor is irradiated with ultraviolet rays or electrons generated by the ionized gas.

Therefore, in manufacturing a gas discharge display device, the technology for manufacturing the discharge space structure is important.

FIG. 1 is a schematic cross-sectional view of a gas discharge display device that utilizes light emission from a phosphor. It has a structure in which a discharge space structure 2 having discharge cells 1 arranged in a matrix is sandwiched between a display plate 4 on which an anode 3 is formed and a substrate 6 on which a cathode 5 is formed.

A phosphor 7 is coated on the wall surface of the discharge space structure 2.
Further, the surrounding area is sealed with a sealant, and the discharge cell is filled with X 凰, Na, or a mixture thereof as a discharge gas. In this type of device, a voltage is applied between a cathode and an anode to generate ultraviolet rays in a discharge gas, causing a phosphor to emit light and display information. In addition, the discharge space structure 2
There is also a type of device that does not coat the wall surface with the phosphor 7 and simply displays information by emitting light from the discharge gas itself.

As can be seen from the above description, in a gas discharge display device, the display brightness, resolution, etc. largely depend on the shape of the discharge space. That is, in manufacturing a gas discharge display device, the manufacturing technology of the discharge space structure occupies an important position. In particular, since full-color gas discharge televisions require high brightness and high resolution, highly accurate discharge space structure fabrication technology is required. Here, to show the structure of the discharge space structure assuming a 40-inch full-color gas discharge television, the shape of a discharge cell with sufficient brightness for practical use is about 0.8 rra square and depth. It is a rectangular parallelepiped space of 1.5 to 2 IIn, and the discharge space structure includes approximately 480 cells in the vertical direction and approximately 8 cells in the horizontal direction through partition walls.
It has a structure in which 00 cells are arranged. Further, this number of cells, etc. is for images in the current NTSC standard mode, and IDTV, EDTV, and HDTV that will be put into practical use in the future will require miniaturization of discharge cells, that is, an increase in the number of discharge cells.

On the other hand, in the above-mentioned 40-inch diagonal full-color television, the number of discharge cells reaches tens of titers, so high processing productivity is also required.

By the way, the discharge spaces of conventional gas discharge display devices are constructed using the following two types of methods.

The first method is grinding, etching, and laser irradiation.

This method uses ultrasonic machining to create a through hole in the material and uses this as a discharge space. In this case, when machining is performed by the grinding method, the cross section of the hole becomes circular, resulting in a problem that the proportion of the discharge space within the plane decreases. Furthermore, there is a problem in that the productivity of square through holes is extremely low. In the etching method, side etching occurs, so the cross-sectional shape is not constant, and the thickness of the material that can be processed is limited to the hole diameter II.
There were problems such as the distance being approximately 0.3 m or less.

In addition, drilling by laser irradiation has the problem of leaving damage around the hole, and ultrasonic processing has the problem of low processing productivity because the processing part called the horn is severely worn out. Ta.

The second method is to configure the discharge space by a thick film process. In this method, a thick ceramic film is formed using a thick film process such as screen printing to form a discharge space, but since the depth of the discharge space that can be created in one process is only about 0.05 m, For example, depth 1a+
It takes 20 repetitions of the process to construct the positive discharge space.

Typically, thick film processes include drying, baking, annealing processes, etc.
Since the process requires a long time, the productivity of this method is low, and since the process is repeated, there is a problem that the cross section of the hole is not constant.

[Problem to be solved by the invention]

As mentioned above, the conventional technology is large screen, high brightness.

Techniques for configuring the discharge space of a gas discharge display device, typified by a full-color television with high resolution, have had the problem of low processing productivity.

The object of the present invention is to have a cross-sectional area of 0.04 to 3 m2. depth is 0
．． The object of the present invention is to provide a high-quality, low-cost gas discharge display device based on a technology for manufacturing a discharge space constituted by discharge cells having a large volume of 2 to 5 m with high productivity.

[Means to solve the problem]

The above purpose is to precisely machine a graphite plate, which has excellent heat resistance and is easy to process, to create a "mold" for the discharge space structure, and fill the voids of this mold with fine ceramic powder such as glass crushed to a size of 300 mesh or less. After that, the glass block is formed by heating, melting, and cooling while excluding oxygen components in an electric furnace or the like, and then the graphite portion is removed to produce a discharge space structure.

[Operation] The operation of the present invention will be explained using FIGS. 2(a) to 2(c).

Graphite plates 11, which have been processed in advance to have a thickness equal to the length of one side of the cross-sectional shape of the discharge cell, are overlapped and sufficiently fixed. Next, using a wire electric discharge machine 12 or the like, integral grooving is performed on the width of the other side of the discharge cell cross-sectional shape.

Next, the graphite plates 11 are disassembled, and spacers or the like are used between the graphite plates to arrange and fix them in a spatial pattern of a gas discharge display device. This creates a mold for producing the discharge space structure.

Next, this is placed in a bottomed workpiece 13, and the cavity is sufficiently filled with ceramic fine powder such as glass.

This is then heated above the melting temperature of the glass in an oxygen-free atmosphere, at which time the graphite is retained as a "mold" and remains in the cooled glass block 15. The graphite in the glass block 15 is removed by heating and burning in oxygen, and then the discharge space structure is completed by slicing the glass block to the length (thickness) of the discharge cell using a wire saw 16 or the like.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2(a) to 2.
This will be explained in detail with reference to FIG. 3(c) and FIG.

High-density graphite block, 30m long and 52m wide
, after processing to thickness II and fixing 40 pieces together,
Grooving was performed by cutting slits at 1 m intervals to a length of 25 nn from the upper end using a 0.2 m wide electrical discharge machining wire 12. Next, this graphite plate 11 is separated,
Alternately shift each sheet by 0.5 rta in the length direction,
And the thickness is 0.25 at the lower part, that is, the part without slits.
A spacer made of graphite plates of rm is sandwiched between the graphite plates 11, and a gap is also provided between the graphite plates 11 to serve as a "mold".
Figure (a)) This was placed in a graphite crucible 13 with a bottom of 80 mm and depth of 50 m++ and fixed. Fine soda-lime glass powder was put into this crucible, and it was confirmed that the void in the "mold" was completely filled, and after filling up to 20 IIn above the "mold", the crucible was set in a silicon unit electric furnace. 1200℃ in a nitrogen gas box.

After being held for 2 hours, the glass block 15 was prepared by slowly cooling the glass block 15 (FIG. 2b)), and then heating it in air to 800° C. to burn off the graphite. This glass block 15 with long through holes was finished to a thickness of 1.5 m using a diamond wire saw 16 to produce a discharge space structure 2 (FIG. 2(C)).

FIG. 3 shows an optical micrograph of the discharge space structure 2 produced by the above method. As can be seen from FIG. It has a structure in which holes are arranged at a pitch of 1.0 m without defects. Furthermore, the processing tolerance was ±0.005%.

Next, an ultraviolet-excited green phosphor (Mn-doped ZnzSiOa) 7 is applied to the wall surface of this discharge space structure 2, and a glass display plate 4 with an anode matrix formed on the upper surface and a glass substrate 6 with a cathode matrix formed on the lower surface are coated. Glue the
A gas discharge display device was manufactured by filling e-gas (first
figure). The anode 3 is a Ni film, and the cathode 5 is a Ba metal film. When the device fabricated in this manner was operated, it was found that the screen brightness was approximately 150 fL, which was sufficient for practical use, and there was no crosstalk between display cells, and the mechanical strength was sufficient. Results were obtained that satisfied the basic specifications required for the device.

Although it may be somewhat difficult to compare the productivity of the technology of the present invention and the conventional technology, for example, 1. the method of creating through holes using only the usual chemical etching method has a slow etching speed; The technical superiority of the present invention is quite high considering that there are problems such as the fact that the production of thin plates of about 2 m is the limit and the stacking type has no choice but to be used.

In addition, the present invention refers to the anode and cathode materials used in the examples.

Needless to say, this is not limited by the phosphor agent or the like.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the discharge space structure of a gas discharge display device can be manufactured with high precision and high productivity, and the gas discharge display device can have high image quality. This has the effect of achieving greater efficiency and lower costs. In particular, it is effective in realizing wall-mounted large-screen full-color televisions, which have been desired to be developed in recent years.

[Brief explanation of the drawing]

Figure 1 is a schematic cross-sectional view of a gas discharge display device, and Figure 2 (a
) to FIG. 2(, ) are schematic diagrams of the manufacturing process according to an embodiment of the present invention, and FIG. 3 is an optical micrograph of a discharge space structure produced according to an embodiment of the present invention. 1... Discharge cell (space), 2... Discharge space structure,
3... Anode, 4... Display board, 5... Cathode, 6...
-Substrate, 7...phosphor, 11...graphite plate,
12... Wire processing machine (part) 13... Work (crucible), 14... Glass powder, 15... Glass block, 16... Wire 87 Figure 28

Claims (1)

[Claims] 1. Filling the "mold" in the part corresponding to the discharge space with ceramic powder such as glass alone or in combination;
A method for manufacturing a discharge space structure, which comprises heating, melting, cooling, and then removing a "mold" portion to form a discharge space. 2. The method for manufacturing a discharge space structure according to claim 1, wherein the constituent material of the "mold" is graphite. 3. The shape of the discharge space is a square with a side length of 0.2 to 1.5 mm, or a rectangle with a long side length of 0.4 to 2.0 mm and a short side length of 0.2 to 1.5 mm. A gas discharge display device characterized by having a discharge space structure.