JPH0721924A - Plasma display panel - Google Patents

Abstract

PURPOSE:To provide a smooth surface insulated layer having the function of a color filter, of an AC type color plasma display panel. CONSTITUTION:The upper parts of color filters 11, 12, 13 each having the function as an insulating layer, are coated with a transparent insulating layer 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel used for an information display terminal, a flat-screen television and the like, and more particularly to a structure of a high contrast and high brightness plasma display panel.

[0002]

2. Description of the Related Art A plasma display panel has Ne.
There are a monochrome panel that uses the emission color of the above and a color panel that uses the emission color of the phosphor. Although the present invention is a technique common to all, a color plasma display panel will be taken as an example here, since a remarkable effect can be obtained particularly in a color plasma display using a phosphor.

A color plasma display panel is a display that excites and emits a fluorescent substance by ultraviolet rays generated by gas discharge to obtain visible light and performs a display operation, and can be classified into an AC type and a DC type according to a discharge method. AC
Among the molds, the reflection type AC surface discharge type is superior in brightness and luminous efficiency, so that the case will be described as an example.

FIG. 2 shows a sectional view of a conventional reflective AC surface discharge plasma display panel. First, the transparent electrode 33 is formed on the front substrate 34. A pulsed AC voltage of usually several tens kHz to several hundreds kHz is applied between the adjacent transparent electrodes 33 to obtain a display discharge. For example, SnO _{2 is} applied to the transparent electrode 33.
To use. The bus electrode 32 is formed on the transparent electrode 33 to reduce the resistance. The bus electrode 32 is formed of, for example, a silver thick film or an Al thin film. In the case of a normal AC type, the bus electrode 32 and the transparent electrode 33 are usually covered with an insulating layer. The insulating layer functions as a color filter to improve the contrast of the panel. That is, a pigment corresponding to the emission color of each discharge cell is mixed in an insulating layer which is usually a thick film of low melting point lead glass. In this conventional example, since a full-color plasma display panel is taken as an example, the colors are red, green, and blue. As a result, the phosphors 23, 24, 2 which are white powders
The decrease in contrast due to the external light scattered by 5 can be reduced. The black partition wall 27 is formed on these color filters 29, 30, 31 by, for example, thick film printing. Further, a protective layer 28 is formed on the surface of the color filter. The protective layer 28 is formed of a thin film of MgO or a thick film.

On the other hand, a data electrode 21 is formed on the rear substrate 20 and is covered with an insulating layer 22, and phosphors 23, 24 and 25 of the luminescent color of each pixel are applied to the portion which becomes each pixel. In the case of this conventional example, phosphor (red) 23, phosphor (green) 24, and phosphor (blue) 25 are applied according to the color of the filter. Here, the phosphor is also formed on the side surface of the white partition wall 26 in order to increase the coating area. The above-mentioned front substrate 34 is adhered to this and hermetically sealed, and a gas capable of discharging, for example, a mixed gas of He and Xe is sealed at about 500 torr. Then, when a pulsed AC voltage is applied between the adjacent transparent electrodes 33, a discharge is generated, and the ultraviolet light generated here excites the phosphor to generate visible light, and the color filters 29, 30, 31 and the front substrate 34. Visible light is extracted through the.

[0006]

In the color plasma display panel having the above-mentioned structure, the color filter is formed by thick film printing of low melting point lead glass mixed with pigment and firing. In the case of a full color plasma display panel, it is necessary to form red, green and blue color filters in a mosaic pattern. Therefore, a seam is formed between the color filters, and the surface becomes considerably uneven. The unevenness has a great adverse effect on the formation process of the black partition formed on the unevenness. In addition, if there is a seam in the color filter that functions as an insulating layer, there is a possibility of causing dielectric breakdown from there. When dielectric breakdown occurs, the surrounding area is contaminated, and defects such as dot defects occur frequently, resulting in a significant decrease in yield. Further, if the firing temperature is excessively increased in order to smooth the seams of the color filters, there is a problem that color mixing occurs between adjacent color filters.

[0007]

The present invention is an AC type plasma display panel having an electrode group covered with an insulating layer, wherein the insulating layer has a first insulating layer having a function of a color filter, And a transparent second insulating layer that covers the first insulating layer. The transparent second insulating layer is formed of low melting point lead glass.

[0008]

According to the present invention, since the insulating layer that functions as a color filter is covered with a transparent insulating layer, the surface is smoothed, and black partition walls can be easily formed in the subsequent step, and dielectric breakdown is prevented. The possibility disappears. Therefore, the yield is also improved. Also, color mixing does not occur.

[0009]

Embodiments of the present invention will now be described with reference to the drawings. Here, the reflective AC surface discharge color plasma display panel described in the conventional example will be described as an example.
It is an invention common to all plasma display panels having an insulating layer covering electrodes. FIG. 1 shows a sectional view of an embodiment of the plasma display panel of the present invention. The basic structure is the same as that of FIG. 2 described in the conventional example, except that the transparent insulating layer 10 is formed on the color filters 11, 12 and 13 which function as an insulating layer. In the process, the color filters 11, 12, and 13 are formed by thick film printing on the front substrate 16 on which the transparent electrodes 15 and the bus electrodes 14 are formed. The paste used for printing is low melting point lead glass powder mixed with various pigments. The softening point of the low melting point glass powder is 500 ° C., for example. Apply this printed paste to a temperature at which color mixing does not occur between the color filters.
For example, firing is performed at about 550 ° C. Then, since the reflowed state is not completely achieved, a seam is formed between the formed color filters. Next, low melting point lead glass powder is applied onto this by thick film printing and fired to form the transparent insulating layer 10. The firing temperature is, for example, about 600 ° C. The low melting point lead glass powder softened by firing fills the gaps of the color filter and reflows, so that the surface is smoothed. However, since the color filter has already been fired once, it does not soften to such a degree that it will flow in this second firing, and color mixing does not occur. Therefore, the black partition wall 8 in the subsequent step can be easily formed, and a smooth transparent insulating film without dielectric breakdown was obtained.

Although the present invention has been described by taking a full-color plasma display panel as an example, it goes without saying that the present invention can be applied to a multi-color plasma display panel or a monochromatic plasma display panel.

[0011]

As described above, according to the present invention, since the insulating layer which functions as a color filter is covered with the transparent insulating layer, the surface is smoothed and the black partition wall can be easily formed in the subsequent step. Therefore, it is possible to obtain an AC type plasma display panel without dielectric breakdown.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is a sectional view of a conventional example.

[Explanation of symbols]

 1,20 Rear substrate 2,21 Data electrode 3,22 Insulating layer 4,23 Phosphor (red) 5,24 Phosphor (green) 6,25 Phosphor (blue) 7,26 White partition 8,27 Black partition 9 , 28 Protective layer 10 Transparent insulating layer 11,29 Color filter (red) 12,30 Color filter (green) 13,31 Color filter (blue) 14,32 Bus electrode 15,33 Transparent electrode 16,34 Front substrate

Claims (2)

[Claims] 1. An AC having an electrode group covered with an insulating layer.
Type plasma display panel, the insulating layer comprises a first insulating layer having a function of a color filter and a transparent second insulating layer covering the first insulating layer. Plasma display panel. 2. The plasma display panel according to claim 1, wherein the transparent second insulating layer is made of low melting point lead glass.