JP3677571B2 - Plasma display panel and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement in a protective layer of a dielectric layer of an AC type plasma display panel (hereinafter abbreviated as PDP).
[0002]
Accompanying the recent colorization of PDPs, AC type PDPs have come to be used as full-color display devices for television receivers, and are particularly attracting attention as large flat displays for high-definition video.
[0003]
In order to use in such applications, it is necessary to increase the definition and extend the life of the PDP as well as an increase in size.
From the above situation, a large-sized, high-definition, long-life PDP is desired.
[0004]
[Prior art]
A conventional PDP will be described in detail with reference to FIG.
FIG. 4 shows the main part of a conventional PDP.
[0005]
As shown in FIG. 4, the main part of the conventional PDP is a plurality of pairs of two parallel display discharge electrodes 12 adjacent to each other on the surface of a 3 mm thick front glass substrate 11 made of soda lime glass. Then, a dielectric layer 13 made of low melting glass covering the discharge electrode 12 and having a film thickness of 50 μm, and a MgO layer 15 having a thickness of 10,000 μm serving as a protective film are formed on the surface of the dielectric layer 13.
[0006]
As a method for forming the MgO layer 15, a vapor deposition method is generally used, but as other methods, a spray method or a coating method using a liquid organic acid metal salt or a paste containing MgO fine powder is applied. A fine powder coating method is also used.
[0007]
On the other hand, address electrodes 17 and strip-shaped barrier ribs (not shown) for defining discharge portions are formed in parallel with each other on the surface of a rear glass substrate 16 made of soda lime glass and having a thickness of 3 mm. The front glass substrate 11 is overlapped with the electrode formation surface facing each other, and the periphery thereof is sealed, and the discharge space formed between these substrates is evacuated, and then 99.9% neon (Ne) And 0.1% xenon (Xe) mixed gas is enclosed as a discharge gas.
[0008]
[Problems to be solved by the invention]
In the conventional AC type PDP described above, a protective layer is provided because it is necessary to lower the discharge start voltage so as to increase the secondary electron emission ratio γ and to improve the sputtering resistance so as to extend the life. In general, a MgO vapor deposition layer is used as the protective layer. When this protective layer is formed by vapor deposition, the underlying dielectric film is a low-melting glass, so that an amorphous layer having a thickness of several thousand mm is first formed, and then a crystalline layer is gradually formed. However, when the usage time of the PDP becomes long, the crystal layer is sputtered to reduce the film thickness. When the sputter reaches the amorphous layer, the drive voltage rises rapidly and becomes higher than the set drive voltage. There was a problem that the life of the PDP was reached.
[0009]
In the spray method or coating method using a liquid organic acid metal salt other than the vapor deposition method, only a protective layer having a film thickness of about 2,000 to 3,000 mm can be formed in one step, and includes MgO fine powder. In the fine powder coating method in which the paste is applied, there is a problem that voids are generated in the formed protective layer.
[0010]
In view of the above situation, the present invention aims to provide a PDP having a protective layer for a dielectric layer that can lower the discharge start voltage and improve the sputtering resistance, and a method for manufacturing the PDP. is there.
[0011]
[Means for Solving the Problems]
The PDP of the present invention is configured to include a protective layer composed of a laminate of an MgO crystal layer and an MgO vapor deposition layer.
[0012]
In the present invention, the MgO crystal layer is formed using MgO fine powder or an organic acid metal salt containing MgO in the lower layer of the MgO layer by vapor deposition, so that the MgO crystal layer on the surface of the dielectric layer can be thickened. Since the crystallinity can also be improved, it is possible to provide a long-life PDP having good sputtering resistance.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS.
FIG. 1 is a diagram showing the main part of the PDP of the present invention, FIG. 2 is a diagram showing an embodiment of the PDP manufacturing method of the present invention in the order of steps, and FIG. 3 is a graph showing the test time of the PDP of the present invention It is a figure which shows the relationship.
[0014]
As shown in FIG. 1, the PDP of the present invention has a surface of a front glass substrate 1 made of soda lime glass having a thickness of 3 mm and a dielectric layer having a thickness of 50 μm made of a discharge electrode 2 and a low melting point glass as in the conventional example. 3 is formed.
[0015]
According to the characteristics of the present invention, the surface of this dielectric layer 3 has a thickness of 2,000 mm MgO crystal layer 4 formed by screen printing and heating and firing , and the thickness of this MgO crystal layer 4 formed by vapor deposition. A protective layer having a two-layer structure composed of a 5,000 mm MgO vapor deposition layer 5 is formed.
[0016]
On the other hand, on the surface of a back glass substrate 6 made of soda lime glass and having a thickness of 3 mm, address electrodes 7 and strip-shaped partition walls (not shown) for defining discharge portions are formed in parallel to each other. The front glass substrate 1 is overlapped with the electrode forming surfaces facing each other, and the periphery is sealed. After the discharge space formed between the substrates is exhausted, 99.9% of neon (Ne) And 0.1% xenon (Xe) mixed gas is enclosed as a discharge gas.
[0017]
The first to fifth manufacturing methods of such a PDP will be described in detail in the order of steps with reference to FIG.
Although the first to fifth manufacturing methods are different in the formation process of the MgO crystal layer, the other manufacturing processes are the same, and therefore the first manufacturing method will be described in detail.
[0018]
First, as shown in FIG. 2 (a), the discharge electrode 2 is formed on the surface of the front glass substrate 1, and the dielectric layer 3 having a thickness of 50 μm covering the front glass substrate 1 and the discharge electrode 2 is formed. The MgO fine powder crystallized on the surface of the dielectric layer 3 is applied by screen printing and dried, and then fired at 500 ° C. to form a MgO crystal layer 4 having a thickness of 2,000 mm.
[0019]
Next, as shown in FIG. 2B, an MgO vapor deposition layer 5 having a thickness of 8,000 mm is formed on the surface of the MgO crystal layer 4 by vapor deposition.
Thereafter, as shown in FIG. 1, the periphery of the rear glass substrate 6 having a thickness of 3 mm made of soda lime glass on which the address electrodes 7 are formed and the periphery of the front glass substrate 1 are sealed, and these front glasses are sealed. Air in the discharge space between the substrate 1 and the rear glass substrate 6 is exhausted, and a mixed gas of 99.9% neon (Ne) and 0.1% xenon (Xe) is sealed as a discharge gas.
[0020]
In the second manufacturing method of PDP, instead of the screen printing method of crystallized MgO fine powder performed in the first manufacturing method, a paste of organic acid metal salt such as magnesium acetate or magnesium propionate is applied by screen printing method. After coating and drying, the MgO crystal layer 4 having a film thickness of 2,000 mm is formed by firing at 500 ° C.
[0021]
In the third production method of PDP, instead of the screen printing method of crystallized MgO fine powder performed in the first production method, MgO fine powder crystallized with an organic acid metal salt such as magnesium acetate or magnesium propionate. The mixed paste is applied by screen printing and dried, and then fired at 500 ° C. to form a MgO crystal layer 4 having a thickness of 2,000 mm.
[0022]
In the fourth manufacturing method of PDP, instead of the screen printing method of crystallized MgO fine powder performed in the first manufacturing method, a mixed paste of crystallized MgO fine powder and low melting glass is applied by screen printing method. After drying, firing is performed at 500 ° C. to form a MgO crystal layer 4 having a thickness of 2,000 mm.
[0023]
In the fifth manufacturing method of the PDP, the MgO crystal layer 4 is formed in the first manufacturing method described above, and cleaning is performed with an ion gun for about 5 minutes before vapor deposition.
FIG. 3 shows the relationship between the test time of the PDP manufactured by these first to fifth manufacturing methods and the amount of change in the discharge voltage.
[0024]
As shown in FIG. 3, the amount of change in the discharge voltage of the conventional PDP is almost the same as the amount of change in the discharge voltage of each example of the present invention until the test time is about 1,000 hours, but is remarkably high when it is about 1,200 hours. The effect of the present invention becomes clear.
[0025]
When each example of the present invention is compared, the change amount of the discharge voltage of Example 3 is the smallest, and the change amount of the discharge voltage of Example 5 performed by adding an ion cleaning process to Example 1 is small, Next, the amount of change in the discharge voltage increases in the order of Example 4, Example 1, and Example 2.
[0026]
Needless to say, the present invention is not limited to the above-described three-electrode surface discharge type ACPDP but also a surface discharge type or counter discharge type ACPDP having two electrodes.
[0027]
【The invention's effect】
As is clear from the above description, according to the present invention, the MgO crystal layer on the surface of the dielectric layer can be thickened, the crystallinity can be improved, and the sputtering resistance can be improved. Therefore, there is an advantage that it is possible to manufacture a PDP having a long life, and it is possible to provide a PDP and a method for manufacturing the PDP that can be expected to have a significant economic and reliability improvement effect.
[Brief description of the drawings]
FIG. 1 is a diagram showing a main part of a PDP of the present invention. FIG. 2 is a diagram showing an example of a manufacturing method of the PDP of the present invention in the order of steps. [Fig. 4] A diagram showing the main part of a conventional PDP [Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Front glass substrate 2 Discharge electrode 3 Dielectric layer 4 MgO crystal layer 5 MgO vapor deposition layer 6 Back glass substrate 7 Address electrode

Claims (4)

In a plasma display panel in which a discharge electrode formed on a substrate is covered with a dielectric layer, and a protective layer is provided on the dielectric layer,
The plasma display panel, wherein the protective layer comprises a laminated structure of an MgO crystal layer and an MgO vapor deposition layer. 2. The MgO crystal layer is formed of a film formed by applying crystallized MgO fine powder, magnesium organic acid metal salt, or a mixed paste of these members , drying and firing. The plasma display panel as described. 3. The plasma display panel according to claim 2, wherein the MgO crystal layer further contains a low melting point glass. 2. When forming the protective layer according to claim 1, after forming an MgO crystal layer on the surface of the dielectric layer, ion-cleaning the surface of the MgO crystal layer and then forming an MgO deposited layer on the surface of the MgO crystal layer The manufacturing method of the plasma display panel characterized by including the process to do.

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