JP4374932B2 - Method for manufacturing plasma display panel - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a plasma display device known as a thin, lightweight display device having a large screen and a method for manufacturing the same.
[0002]
[Prior art]
In recent years, there has been a demand for higher performance of displays such as high-quality displays and large screens, and various displays have been developed. Typical displays that are attracting attention include CRT displays, liquid crystal displays (LCDs), plasma display panels (PDPs), and the like.
[0003]
In general, a PDP has two thin glass plates with a plurality of electrodes and a dielectric layer disposed opposite each other with a plurality of partition walls, and a phosphor layer is disposed between the plurality of partition walls. It has a configuration in which discharge gas is sealed between the plates and hermetically bonded. Then, the plurality of electrodes are fed with power and fluorescent light is emitted by the discharge generated in the discharge gas. Therefore, even if the screen is enlarged, the depth dimension and weight are hardly increased as in a CRT, and the viewing angle is not limited as in an LCD. Recently, a PDP having a large screen of 60 inches or more has been commercialized.
[0004]
Here, usually, the dielectric layer is a precursor material (for example, paste) in which glass powder, a cellulose or acrylic thickener resin, and a vehicle composed of an alcohol or ester organic solvent are mixed. , Sheet, etc.) are applied and formed, and baked in air under atmospheric pressure to evaporate, burn and decompose the volatile matter of the vehicle, and then melt and sinter the glass powder. The firing temperature is about 500 ° C. to 600 ° C. (for example, see Non-Patent Document 1).
[0005]
[Non-Patent Document 1]
Heki Uchiike and Shigeo Miko, “All about Plasma Display”, Industrial Research Committee, Inc., May 1, 1997, p86-p87,
[0006]
[Problems to be solved by the invention]
However, bubbles may be mixed in the dielectric layer during the firing process. In such a case, the performance of the dielectric layer such as a decrease in withstand voltage and a decrease in light transmittance decreases, and the PDP displays. In some cases, there is a problem that the characteristics of the image to be deteriorated.
[0007]
The present invention has been made in view of the above problems, and an object of the present invention is to realize a method of manufacturing a PDP having excellent image display characteristics by forming a good dielectric layer.
[0008]
[Means for Solving the Problems]
To achieve the above object, the present invention provides a method for manufacturing a plasma display panel having a front plate in which a plurality of display electrodes including scan electrodes and sustain electrodes are formed and a dielectric layer is formed to cover the display electrodes. The dielectric layer is formed by applying and firing a precursor material containing glass powder and an organic solvent. After the organic substances during the reaction have been reacted and removed, the glass powder is sintered and softened. The period until the cooling process is started is characterized by firing in an oxygen atmosphere of 40 vol% or more .
[0009]
This replaces the gas trapped in the gaps between the glass powders, which will form bubbles in the dielectric layer after firing, with high-concentration oxygen, and the oxygen and the dielectric composition react to form oxygen. Since it is dissolved in the glass as an oxide, bubbles contained in the dielectric layer are reduced, and a good dielectric layer can be obtained.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
That is, according to the first aspect of the present invention, a plasma display panel having a front plate in which a plurality of display electrodes including scan electrodes and sustain electrodes are formed and a dielectric layer is formed so as to cover the display electrodes. In the method, the dielectric layer is formed by applying and firing a precursor material containing glass powder and an organic solvent, and after the organic substances at the time of firing react and are removed, the glass powder is sintered and softened. It is a method for manufacturing a plasma display panel, characterized by firing in an oxygen atmosphere of 40 vol% or more during a period until the cooling process is started.
[0011]
The invention according to claim 2 of the present invention is characterized in that, in the invention according to claim 1, a reduced-pressure atmosphere of 9.0 × 10 ⁴ Pa is applied during firing.
[0012]
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0013]
FIG. 1 is a cross-sectional perspective view showing an example of a schematic configuration of a PDP manufactured according to an embodiment of the present invention.
[0014]
The front plate 2 of the PDP 1 is formed by forming a plurality of display electrodes 6 composed of scanning electrodes 4 and sustain electrodes 5 on a smooth, transparent and insulating substrate 3 such as float glass. A dielectric layer 7 is formed so as to cover, and a protective layer 8 made of MgO is further formed on the dielectric layer 7. Scan electrode 4 and sustain electrode 5 are transparent electrodes 4a and 5a serving as discharge electrodes, and bus electrodes 4b and 5b made of Cr / Cu / Cr, Ag, or the like electrically connected to transparent electrodes 4a and 5a, respectively. It consists of and.
[0015]
The back plate 9 has a plurality of address electrodes 11 formed on an insulating substrate 10 such as glass, and a dielectric layer 12 is formed so as to cover the address electrodes 11. A partition wall 13 is provided on the dielectric layer 12 at a position corresponding to between the address electrodes 11, and phosphor layers 14 </ b> R of red, green, and blue colors are provided between the surface of the dielectric layer 12 and the side surface of the partition wall 13. , 14G, and 14B.
[0016]
The front plate 2 and the rear plate 9 are disposed to face each other with the partition wall 13 interposed therebetween so that the display electrodes 6 and the address electrodes 11 are orthogonal to each other and form the discharge space 15. The discharge gas is filled with at least one kind of rare gas of helium, neon, argon, and xenon, and is partitioned by the partition wall 13 to discharge at the intersection of the address electrode 11, the scan electrode 6, and the sustain electrode 7. The space 15 operates as the discharge cell 16.
[0017]
Further, as a method of manufacturing the PDP 1 as described above, first, the display electrode 6 is formed on the substrate 3, and the precursor material of the dielectric layer 7 is applied thereon and baked, whereby the dielectric layer 7 is formed. Form. Next, the front plate 2 is obtained by forming the protective layer 8 on the dielectric layer 7 by forming a film such as MgO by an electron beam evaporation (EB evaporation) method or the like. Here, as a precursor material of the dielectric layer 7, glass powder, a cellulose or acrylic thickener resin, and a vehicle made of an alcohol or ester organic solvent are mixed, for example, a paste In addition, examples of the glass powder include ZnO—B ₂ O ₃ —SiO ₂ based mixture, PbO—B ₂ O ₃ —SiO ₂ based mixture, and PbO—B ₂ O. ₃ -SiO ₂ -Al ₂ O ₃ based _{mixtures, PbO-ZnO-B 2 O} 3 -SiO 2 based _{mixtures, Bi 2 O 3 -B 2 O} 3 and the like can be given -SiO ₂ based mixtures.
[0018]
Further, the data electrode 11 is formed on the substrate 10, and a dielectric material 12 is applied thereon and baked to form the dielectric layer 12. Then, barrier ribs 13 made of low-melting glass are formed in a predetermined pattern, and phosphor layers 14R, 14G, and 14B are formed by applying and firing a phosphor material between the barrier ribs 13. Then, for example, a low melting point frit glass material is applied to the periphery of the substrate 10, and baking is performed to remove the resin component, thereby forming a sealing member (not shown) to obtain the back plate 9.
[0019]
Next, the front plate 2 and the back plate 9 obtained as described above are relatively aligned, and in that state, by heating while being fixed, the sealing member (not shown) is softened. After performing a so-called sealing process in which the front plate 2 and the back plate 9 are joined in an airtight manner, and then performing a so-called exhaust baking process in which the discharge space 15 is evacuated while being heated, a discharge is made in the discharge space 15. PDP1 is manufactured by enclosing gas.
[0020]
Here, a method of forming the dielectric layer 7 which is a characteristic point of the present invention will be described below.
[0021]
FIG. 2 is a perspective view showing a schematic configuration of an example of a baking apparatus used for baking when the dielectric layer 7 is formed.
[0022]
A precursor material of a dielectric layer is formed on the substrate 3 on which the display electrode 6 (FIG. 1) is formed by a screen printing method or a laminating method so as to cover the display electrode 6, and the precursor material is installed in the baking apparatus 21. After that (the support means for the substrate 3 in the baking apparatus 21 is not shown), the valve 22 is opened, and a gas containing oxygen is supplied into the baking apparatus 21 by an air supply device 23 (for example, a fan). 3 is heated to a predetermined temperature and held at that temperature (heater not shown). Here, in order to exhaust the gas generated by the reaction between the precursor material of the dielectric layer and the oxygen-containing gas in the firing device 21, the valve 24 is opened and the exhaust device 25 ( For example, exhaust is performed by a fan).
[0023]
Here, the gas containing oxygen can be manufactured and supplied by, for example, the oxygen supply device 26 (for example, an oxygen-enriched film), and the oxygen ratio is 40 vol% or more, preferably 80 vol% or more. The gas contained in the gap between the glass powders in the precursor material is replaced with high-concentration oxygen, and the substituted oxygen is reacted with the precursor material of the dielectric layer to form an oxide in the glass. It has been confirmed by the study conducted by the present inventors that the bubbles contained in the dielectric layer can be reduced by dissolving them.
[0024]
Here, the timing of introducing the gas containing oxygen into the baking apparatus 21 may be always introduced from the start to the end of baking, but the organic substance contained in the vehicle reacts violently with oxygen. Since the surface of the dielectric layer is roughened and the optical characteristics are deteriorated, and after the glass powder is softened, the gas cannot be replaced and oxygen is wasted. After the reaction and effective removal as carbon dioxide gas (so-called burnout), it is preferable to go through a sintering and softening process of glass powder and enter a cooling process (so-called slow cooling process).
[0025]
Further, by adjusting the balance between the air supply by the air supply device 23 and the exhaust by the exhaust device 25, the inside of the firing device 21 is less than 1.01325 × 10 ⁵ Pa (atmospheric pressure), that is, for example, 9.0. It is the inventors of the present invention that the effect of reducing the gas (bubbles) contained in the dielectric layer 7 can be sufficiently obtained when the pressure is reduced to about 10 ⁴ Pa compared to firing under atmospheric pressure. Has been confirmed by the study conducted by. Here, the adjustment of the balance may be performed by opening and closing the valve 22 and the valve 24, for example. Further, the timing of depressurization may be always performed from the start to the end of the heat treatment, but it is sufficiently effective through the sintering and softening processes to the cooling process (so-called slow cooling process).
[0026]
In the present invention, the case of baking with a batch type baking apparatus has been described, but a continuous type baking apparatus may be used. Furthermore, the opening for supplying and exhausting air to the firing device 21 is not limited to that shown in the figure.
[0027]
【The invention's effect】
As described above, according to the present invention, it is possible to reduce the bubbles mixed in the dielectric layer, further reduce the number of bubbles, and improve the dielectric layer withstand voltage characteristics, improve the light transmittance, etc. A dielectric layer can be formed, and a method for manufacturing a PDP having excellent image display characteristics can be realized.
[Brief description of the drawings]
FIG. 1 is a cross-sectional perspective view showing a schematic configuration of a PDP manufactured by a method for manufacturing a plasma display panel according to an embodiment of the present invention. FIG. 2 shows a method for manufacturing a plasma display panel according to an embodiment of the present invention. A perspective view showing a schematic configuration of a firing apparatus used [Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Plasma display panel 2 Front plate 4 Scan electrode 5 Sustain electrode 6 Display electrode 7 Dielectric layer 9 Back plate

Claims (2)

Display electrodes formed of scan electrodes and the sustain electrodes form a plurality, Oite the method for manufacturing a plasma display panel having a front plate having a dielectric layer covering the display electrodes,
The dielectric layer is formed by applying and baking a precursor material containing glass powder and an organic solvent,
After the organic substance at the time of the firing reacts and is removed, the glass powder is fired in an oxygen atmosphere of 40 vol% or more after the sintering and softening processes until the cooling process is started. A method for manufacturing a plasma display panel. The method for producing a plasma display panel according to claim 1, wherein a reduced-pressure atmosphere of 9.0 x 10 ⁴ Pa is set during firing.

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