JPH07147149A - Flat plate image display device and its manufacture - Google Patents

Abstract

PURPOSE:To provide a display device using electron beams Which is excellent in life characteristic by constituting a holder for linear cathode from a metal base and an electric insulating layer of crystallized hyaline in which at least a MgO crystal phase is precipitated on the metal base. CONSTITUTION:A flat type image display device has linear beam sources 3, electron beam taking means 5, 6, 7, an electron beam control means 8, electron beam polarizing means 9, 10, and a light emitting means 11. A linear cathode holder 4 for fixing and positioning the linear beam sources 3 arranged in a plurality of lines is formed of an electric insulating base, and the electric insulating base is formed of a metal base 12 and an electric insulating layer 14 of crystallized hyaline in which at least a MgO crystal phase is precipitated on the metal base 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat plate type image display device for displaying an image by controlling an electron beam emitted from a flat electron source by an electron beam control electrode and accelerating and projecting it onto a phosphor surface. Regarding manufacturing method.

[0002]

2. Description of the Related Art In the fields of AV typified by televisions and OA typified by personal computers, a new era of displays is approaching, and there is a demand for the development of new displays to meet the demand. For example, in personal / household information devices found in laptop computers and word processors, thin and lightweight displays are required while having large screens with good visibility. Conventionally, devices using EL, plasma, liquid crystal, etc. have been developed as matrix type flat panel display devices, but they have advantages and disadvantages in terms of brightness, luminous efficiency, color display, large size, etc. It is not a method. On the other hand, attempts have been made to construct a flat image display device using an electron beam, which is expected to be a method capable of solving the above problems. However, it has not yet been put to practical use.

[0003]

A basic configuration example of a conventional flat plate image display device using an electron beam will be described with reference to FIG. This display device has a back container 1, a back electrode 2 for controlling an electron beam, a line cathode 3 as a beam source, a line cathode holder 4 for fixing and positioning the line cathode, and an electron beam accelerated in this order from the rear to the front. Grid electrodes 5, 6, 7, and 8, a horizontal deflection electrode 9 that deflects an electron beam, a vertical deflection electrode 10, and a screen 11 that emits light by collision of an electron beam are arranged.
These are housed inside the evacuated interior of a flat glass bulb. Here, the wire cathode 3 is made of tungsten and Ba.
SrCa (CO ₃ ) ₂ is coated. An alumina ceramics substrate is used for the wire cathode holder 4.

By the way, the line cathode vibrates when the image display device is turned on and off. When this is repeated, there is a phenomenon that the wire cathode is worn and finally the wire cathode is broken. The reason for this is that the Vickers hardness of tungsten is 700 and the alumina substrate 4 is as high as 1500, and the tungsten wire with low hardness is broken due to wear of both.

That is, the conventional flat panel image device has a problem in life characteristics.

An object of the present invention is to provide a flat image display device using an electron beam having excellent life characteristics in consideration of the problems of the conventional flat image display device.

[0007]

A holder for a line cathode of a flat panel image display device according to the present invention comprises a metal substrate and a crystalline glass vitreous electric insulating layer in which at least a MgO-based crystal phase is deposited on the metal substrate. It is composed of and.

[0008]

With the above structure, it is possible to provide a flat-panel image display device using an electron beam, which is superior in life characteristics to the conventional one.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 2, the flat panel image display apparatus according to one embodiment of the present invention is provided with linear beam sources 3 arranged in a plurality of rows and an electron beam for extracting the electron beams from the electron sources 3. Electron beam extraction means 5, 6, 7 and electron beam control means 8 for controlling an electron beam arranged in a direction intersecting the linear electron sources arranged in the plurality of rows and for deflecting the electron beam. Electron beam deflecting means 9 of
10 and a light emitting means 11 for emitting light by electron beam bombardment
And a wire cathode holder 4 for fixing and positioning the beam source 3 is an electrically insulating substrate, and the electrically insulating substrate is a metal substrate 12, and at least on the metal substrate 12,
It is composed of a crystallized vitreous electric insulating layer 13 in which a MgO-based crystal phase is deposited. The detailed structure is as follows. (1) Metal Substrate The metal substrate used in this embodiment is selected from various types of alloys such as hollow steel plates, stainless steel plates, silicon steel plates, nickel-chromium-iron, nickel-iron, kovar, invar, and clad materials.

Once the material of the base material is determined, the desired shape processing, hole processing, etc. are performed by ordinary mechanical processing, etching processing, laser processing, etc. These metal substrates are used for the purpose of improving the adhesion of the holo layer. After the surface is degreased, various platings such as nickel and cobalt are applied, or an oxide coating layer is formed by thermal oxidation treatment. (2) Electrical Insulation Layer From the viewpoint of electrical insulation and heat resistance of the electrical insulation layer, the vitreous layer used in the present invention is a non-alkali crystallized glass (when fired, a crystalline phase of at least 2MgO.B ₂ O ₃ is formed. It is preferable to be composed of (precipitation). Its glass composition is
For example SiO ₂ 7 to 23 wt% B ₂ O ₃ 10~34 wt% MgO 16 to 50 wt% CaO 0 to 20 wt% BaO 0 to 50 wt% ZrO ₂ 0 to 5 wt% P ₂ O ₅ 0~5 wt % La ₂ O ₃ 0 to 40 wt% composition. The reason why the vitreous layer having the above composition range is selected is that there is a demand for heat resistance due to heating of the wire cathode described later.

Further, as a method for coating the above-mentioned crystallized glass on a metal substrate, there are a usual spray method, a powder electrostatic coating method, an electrophoretic electrodeposition method and the like. The electrophoretic electrodeposition method is the most preferable from the viewpoint of the denseness of the coating film, the electric insulation property, and the like.

According to this method, glass, alcohol and a small amount of water are added, and the mixture is crushed and mixed in a ball mill for about 20 hours to make the average particle diameter of glass about 1 to 5 μm. The obtained slurry is put in an electrolytic cell and the liquid is circulated. Therefore,
The metal substrate prepared in (1) is immersed in this slurry and negatively polarized at 100 to 400 V to deposit glass particles on the surface of the metal substrate. After drying this, 8
Baking is performed at 50 to 900 ° C. for 10 minutes to 1 hour. This gives an electrically insulating layer.

It is necessary that at least the MgO-based crystal phase be deposited in the electrically insulating layer by firing. The reason is as shown in the thermal expansion curve of FIG.
In the case of (a) in the glass state (amorphous state), 60
It has a yield point at 0 to 700 ° C. However, when this is heat-treated (baked) to precipitate at least the MgO-based crystal phase, the yield point becomes 900 ° C. or higher as shown in (b), and the heat resistance is improved.

Next, the present embodiment will be described more specifically.

Example 1 Crystallized glass as shown in (Table 1) to (Table 3) was synthesized, and SU was prepared according to the above-mentioned steps.
A 100 μm thick crystallized glassy layer is electrophoretically electrodeposited on the surface of S430 base material (300 mm × 300 mm × 0.5 mm) and baked at 880 ° C for 10 minutes to obtain sample surface roughness, waviness and heat resistance. The results of various characteristics such as

[0017]

[Table 1]

[0018]

[Table 2]

[0019]

[Table 3]

The surface roughness was measured with a Talysurf surface roughness meter and indicated by the surface center line average roughness Ra, and the waviness was expressed by the difference Rmax between the peak and the valley obtained by the Talysurf surface roughness meter.

Regarding the heat resistance, the sample was put in an electric furnace at 850 ° C. for 10 minutes, taken out of the furnace, and allowed to cool naturally for 30 minutes. A spalling test was repeated, and the state of cracking and peeling of the sample was examined. . The cracks were immersed in the red ink, the surface was wiped off, and the presence or absence of the cracks was checked by visual observation. ○, △, × in the table
Indicates that no abnormality was observed even after 10 cycles or more, Δ indicates that the abnormality occurred in 5 to 9 cycles, and x indicates that the abnormality occurred in 4 cycles or less.

Based on the above evaluations, a comprehensive evaluation was performed, and the results are shown by ◯, Δ, and x. Nos. 1 to 5 are those in which SiO ₂ and B ₂ O ₃ are changed while keeping other components constant, No.
6 to 12 make SiO ₂ / B ₂ O ₃ almost constant and MgO
No. 13 to 16 that changed the amount are the same as CaO.
What changed the amount. No. 17 to 21 are also Ba
The amount of O changed. No22 to 26 are also L
a The amount of ₂ O ₃ was changed. No27~41 respectively show the effect of _{ZrO 2, TiO 2, SnO 2} , P 2 O 5, ZnO.

As is clear from (Table 1) to (Table 3),
If the amount of SiO ₂ is increased, the heat resistance will improve, but the surface properties will deteriorate. On the contrary, if the amount of B ₂ O ₃ is increased, the surface property is certainly improved, but the heat resistance is decreased. Therefore, in the present invention, SiO ₂ 7 to 23 wt%, B ₂ O ₃ 1
It is preferably in the range of 0 to 34% by weight.

The amount of MgO has a correlation with the crystallinity, and if it is 16% by weight or less, the precipitation of crystals is insufficient and the heat resistance is poor. Also,
If it is 50% by weight or more, crystals tend to be precipitated and easily crystallize when the glass is melted, and it is difficult to obtain a homogeneous glass, and the surface roughness becomes large.

When the amount of CaO is 20% by weight or more, the surface property is deteriorated, which is not preferable.

When the amount of BaO is 50% by weight or more, the heat resistance is deteriorated, which is not preferable.

When the amount of La ₂ O ₃ is 40% by weight or more, heat resistance deteriorates, which is not preferable.

Other components that can be added are ZrO ₂ , Ti
O ₂ , SnO ₂ , P ₂ O ₅ , ZnO and the like can be mentioned, but 5
It can be added up to a weight% of less.

(Example 2) SUS having 10 through holes
430 (100 mm x 100 mm x 0.5 mm) substrate surface,
Example 1 Using the glass of No. 3 composition, a sample was formed by electrophoretic electrodeposition, spraying, and powder electrolysis to have a film thickness of 100 μm and fired to prepare a sample. With respect to the insulation properties of these peripheral portions of the through holes, a 1 mA breakdown voltage value was measured using a withstand voltage meter. The results are shown in (Table 4).

[0030]

[Table 4]

As is clear from (Table 4), the electrophoretic electrodeposition method, which is a requirement of the present invention, is excellent in electrical insulation.

(Embodiment 3) Invar (230 mm × 10 mm)
(5 mm) A negative electrode holder sample was experimentally manufactured in the same manner as in Example 1 by using glass having the composition of Example 1 and No3 on the surface of the substrate. It was mounted on a flat panel image display device as shown in FIG. For comparison, a flat panel image display device was similarly prototyped using alumina substrates of the same shape.

As a test method, the micro-Vickers hardness of each sample was measured by using a Vickers hardness meter, and repeated tests were carried out with one cycle of energization of the flat panel imager for one minute and one minute off as one cycle. The number of repetitions up to the disconnection was investigated.

The results of these tests are shown in (Table 5).

[0035]

[Table 5]

As is clear from Table 5, the Vickers hardness of the negative electrode holder of this embodiment is close to the Vickers hardness of 700 of the tungsten negative electrode. As a result, when the negative electrode holder of the present embodiment is used, wear due to the difference in hardness is small, and therefore the negative electrode is not broken even in the on-off test of the flat panel image device.

[0037]

As is apparent from the above description,
By using the negative electrode holder of the present invention, it is possible to provide a flat image display device using an electron beam, which is free from disconnection of the negative electrode and excellent in life characteristics as compared with the conventional case.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a line cathode holder for a flat image display device according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a conventional flat image display device.

FIG. 3 is a diagram of linear expansion curves of crystallized glass and glass according to the present invention.

[Explanation of symbols]

 1 Back Container 2 Back Electrode 3 Wire Cathode 4 Wire Cathode Holder 5 Grid Electrode 6 Grid Electrode 7 Grid Electrode 8 Grid Electrode 9 Horizontal Deflection Electrode 10 Vertical Deflection Electrode 11 Screen Emitting by Electron Beam Collision 12 Metal Substrate 13 Crystallized Glass Electrical insulation layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akihiko Yoshida 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (3)

[Claims] 1. A linear beam source arranged in a plurality of rows,
Electron beam extraction means for extracting an electron beam from the electron source, electron beam control means for controlling the electron beam arranged in a direction intersecting the linear electron sources arranged in the plurality of rows, and the electron beam In a flat panel image display device provided with an electron beam deflecting means for deflecting an electron beam and a light emitting means for emitting light by electron beam bombardment, a wire cathode holder for fixing and positioning the beam source is an electrically insulating substrate. The electrically insulating substrate is composed of a metal substrate and at least a crystallized glassy electrical insulating layer in which a MgO-based crystal phase is deposited on the metal substrate. Image display device. 2. The crystallized vitreous electrical insulation layer comprises, as a main component, at least wt% MgO; 16-50%, B
aO; 0 to 50%, CaO; 0 to 20%, La ₂ O ₃ ; 0
_{~40%, B 2 O 3;} 10~34%, SiO 2; 7~23
%, MO ₂ (M is at least 1 of Zr, Ti and Sn)
_{Species); 0~5%, P 2 O} 5; flat panel display device according to claim 1, characterized in that 0 to 5%. 3. A method for manufacturing a flat panel image display device, comprising forming the crystallized glassy electric insulating layer according to claim 1 by an electrophoretic electrodeposition method and baking the same.