JP2815012B2 - Method of manufacturing color discharge display panel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a color discharge display panel used for displaying information and displaying a television image, and more particularly to a method for manufacturing a color discharge display panel for improving emission luminance.

[0002]

2. Description of the Related Art A discharge display panel is a device which emits light by utilizing gas discharge, and has excellent features such as a large nonlinearity of a discharge phenomenon, a high-speed response, and a specific memory effect. It is widely used for information display devices and the like. At present, the ones that are practically used are those that display red and orange in a single color by discharge light emission of Ne, but the phosphor applied to the inner wall of the discharge cell using a discharge gas that generates ultraviolet rays such as Xe. Thus, full-color display can be realized by converting into visible light such as red, green, and blue.

[0003] Such color discharge display panels have various structures, and can be classified into a transmission type and a reflection type according to the application position of the phosphor powder. The transmissive type is a panel in which a phosphor is applied to a front substrate side which is a display surface, and a light emitting display is viewed through a phosphor layer. On the other hand, in the reflection type, a phosphor is applied to the inner wall of the rear substrate or the partition wall for separating the discharge cells on the display rear side. The reflection type has a higher dot brightness than the transmission type because the light emission of the phosphor is directly viewed through the transparent front substrate, and is advantageous over the transmission type if some measures are taken to increase the aperture ratio.

However, even in such a reflection type, light generated from the phosphor is radiated in all directions, so that the amount of light extracted to the display side and contributing to display is considerably reduced. In order to improve this, a method employing a white glaze layer has been used.

FIG. 3 is a partial sectional view of a panel showing an example of a reflection type. On the back substrate 31, a white glaze layer 36 and a phosphor layer 35 are formed. A discharge cell 33 defined by the front substrate 32 and the partition 34 is formed. A discharge gas containing Xe is sealed in the discharge cells 33. The electrode structure includes a DC type and an AC type using an electrode covered with a dielectric layer. In addition, the surface discharge configuration and one pixel 3
Although there are various types such as an electrode structure, the present invention is not directly related to the electrode structure, and therefore, FIG. 3 shows one in which the electrodes are omitted for simplification.

The phosphor layer 35 emits visible light due to ultraviolet rays generated by the discharge. Light emitted upward from the phosphor layer 35 is effectively extracted as display light, but light emitted downward from the phosphor layer 35 is emitted almost directly to the rear surface without the white glaze layer 36, contributing to display. do not do. When there is a white glaze layer 36 as shown in FIG.
A part of the light is diffusely reflected and returned to the display side, and an improvement in luminance is obtained. Such a white glaze layer is mainly composed of lead glass having a low softening point, and a fine powder such as alumina or titanium oxide having a different refractive index from the glass component is dispersed therein, and is formed by screen printing. The white glaze layer often has a diffuse reflection function by whitening the glaze layer formed as an AC-type dielectric layer or an interlayer insulating layer having a multilayer electrode structure.

[0007]

As described above, the display brightness is improved by disposing the white glaze layer under the phosphor layer, but the useless light emitted to the rear side is also reduced. There are still many, and the improvement effect is not enough. this is,
This is because the reflection performance of the white glaze layer is not so good. Factors that determine the performance of such diffuse reflection include:
There are a difference in refractive index between the dispersed powder and the glass medium, a particle diameter of the dispersed powder, a packing density, and the like. In the white glaze layer, since the refractive index of lead glass is as large as about 1.7, the difference in refractive index from the dispersion powder cannot be made large. In addition, when the amount of the dispersed powder is increased, a good layer cannot be formed without reflow even at the sintering temperature, so that the amount of the mixed powder cannot be increased. For these reasons, the reflectivity of the white glaze layer is not so large, and the luminance is not sufficiently improved. Also,
Aside from the case where the white glaze layer is also used as the dielectric layer of the AC type panel and the like, if it is newly formed as a reflective layer, there is a problem that the manufacturing cost is greatly increased.

The present invention has been made in view of such a conventional situation, and is intended to provide a color discharge display panel having a high display luminance with a high reflectance at the lower portion of the phosphor, a low manufacturing cost, and a low manufacturing cost. It is intended to provide a manufacturing method.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a method of manufacturing a color discharge display panel having discharge cells defined by partition walls between a rear substrate and a front substrate as a display side. The color discharge display panel is characterized in that a white pigment powder paste is screen-printed on the back substrate and dried, and a phosphor paste is screen-printed on the dried white pigment layer and both are fired simultaneously. It is a manufacturing method.

[0010] The diffuse reflection layer formed below the phosphor layer of the present invention is made of fine white pigment powder. As this white pigment, it is possible to use various oxides such as titanium oxide, barium oxide, lead oxide, magnesium oxide, and aluminum oxide, sulfides such as zinc sulfide, and further, fine white powders of nitrides and fluorides. it can. Among them, with high refractive index,
Titanium oxide is the most practical in that it can be obtained at a low price. Since this white pigment layer is different from the white glass layer and is merely a powder layer, the refractive index difference from the refractive index (about 1) of the discharge gas is large, and a fine powder layer densely packed may be used. High reflection performance because it can. Such a structure can be easily realized by applying a white pigment powder by a similar method before applying the phosphor powder.

[0011]

Next, an embodiment of the present invention will be described in detail.

FIG. 1 is a partial sectional view of an example of a color discharge display panel according to the present invention. In the method of manufacturing the discharge display panel, first, the write electrode 7 is formed on the rear substrate 1 made of glass. Thereafter, a paste made of titanium oxide fine powder having an average particle diameter of 0.3 μm, a binder, a solvent, and the like was printed in a predetermined dot shape by screen printing to form a white pigment layer 9. After drying at 120 ° C., the blue phosphor powder (BaMgAl
_A paste composed of ₁₄ O ₂₃ : Eu), a binder, a solvent, and the like was screen-printed on one-third of the titanium oxide dots and dried to form a phosphor layer 10 a.

Further, green phosphor powder (Zn ₂ SiO ₄ : M)
n) and a red phosphor powder ((Y, Gd) B)
The paste of O ₃ : Eu) was printed on one-third of the titanium oxide dots at different positions in the same manner as the blue phosphor powder to form phosphor layers 10b and 10c. This substrate is
Baking at 00 ° C. to remove the binder component and remove the titanium oxide white pigment layer 9 and the blue, green and red phosphor layers 10 a to 1
The back substrate portion on which 0c was formed was completed. The thickness of each phosphor layer was about 10 μm.

On the other hand, a surface discharge electrode 6 designed to have a sufficient opening is formed on the front substrate 2, and a glass layer formed by a thick film technique and an oxidized film formed by vacuum deposition are formed thereon. A dielectric layer 8 made of a magnesium surface protective layer is formed. A center sheet glass plate having a large number of fine holes was sandwiched between a front substrate portion and a rear substrate portion as a partition wall 4, and discharge cells 3 were formed and the whole was sealed to complete a panel. A He-Xe mixed gas containing 1% of Xe was sealed as a discharge gas. When this panel was allowed to emit light, a luminance of 110 cd / m ² was obtained on a white surface.

On the other hand, a panel without the white pigment layer 9 was manufactured, and the luminance was measured under the same driving conditions as described above.
5 cd / m ² , confirming the effect of the white pigment layer.
When the titanium oxide white pigment layer is thin, the reflection effect is small, and when the thickness is large, the reflection performance is saturated, but there is a problem in production. Therefore, the thickness is preferably about 1 μm to 30 μm.

FIG. 2 is a partial sectional view of a panel showing a second embodiment in which a white pigment layer and a phosphor layer are also formed on the partition wall. This panel is substantially similar in structure to that of FIG. 1, but in this example, a partition 24 is directly formed on a rear substrate 21 to constitute a discharge cell 23. The partition wall 24 is a black insulator in which low-melting glass and fine powder such as aluminum oxide and iron oxide are mixed, and is formed by a thick film technique. A paste composed of fine powder of titanium oxide and a water-insoluble binder was uniformly applied and dried on the entire surface. Thereafter, a photosensitive paste composed of a phosphor powder and PVA or the like was applied, and drying, exposure, and development were repeatedly performed on the blue, green, and red phosphors, followed by firing at 500 ° C.

The discharge cell 23 thus obtained is
The white pigment layer 29 and the phosphor layer 2 are also formed on the partition wall of the rear substrate.
Since the layers 5a, 25b, and 25c are formed, higher luminance can be obtained.

In the above example, titanium oxide powder was used for the white pigment layer, but other materials can be used as long as the powder has a high refractive index. In addition, in order to improve the adhesion strength of the white pigment layer, a small amount of glass components are mixed,
The particles may be crosslinked.

[0019]

As described above, according to the present invention, there is provided a color discharge display panel with improved light emission luminance of a color plasma display. In addition, the discharge display panel of the present invention can form the reflective layer in the same process as the application of the phosphor powder layer, so that no new equipment is required. Few. Also,
According to the configuration of the present invention, the phosphor layer can be made thinner, and there is also an advantage that the amount of expensive phosphor material used can be reduced.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of a color discharge display panel obtained according to a first embodiment of the present invention.

FIG. 2 is a partial cross-sectional view of a color discharge display panel obtained according to a second embodiment of the present invention.

FIG. 3 is a partial cross-sectional view of an example of a conventional color discharge display panel.

[Explanation of symbols]

1,21,31 Back substrate 2,22,32 Front substrate 3,23,33 Discharge cell 4,24,34 Partition wall 6,26 Surface discharge electrode 7,27 Write electrode 8,28 Dielectric layer 9,29 White pigment layer 10a, 10b, 10c, 25a, 25b, 25c, 3
5 phosphor layer 36 white glaze layer

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H01J 9/227 H01J 11/00-11/02 H01J 17/49

Claims (3)

(57) [Claims] 1. A method of manufacturing a color discharge display panel having discharge cells defined by partition walls between a rear substrate and a front substrate serving as a display side, wherein a white pigment powder paste is formed on at least the rear substrate of the inner wall of the discharge cells. Screen-printing a white pigment powder layer, screen-printing a phosphor paste on the white pigment powder layer, and simultaneously firing the white pigment powder layer and the phosphor paste to form a white pigment. A method for manufacturing a color discharge display panel, comprising forming a reflection layer made of a powder and a phosphor layer formed on the reflection layer. 2. The method according to claim 1, wherein the white pigment powder paste is also formed on the partition. 3. The method of claim 2, wherein the phosphor paste is also formed on the white pigment powder layer formed on the partition.