JPH04262340A - Plasma display panel - Google Patents

Abstract

PURPOSE:To prevent missing due to spacer severance in the process of forming the spacer, and enhance the contrast ratio. CONSTITUTION:On a transparent dielectric substance layer 3 and another dielectric substance layer 7 a spacer 4 is formed consisting of a hybrid sintering of a filler of oxide ceramic particulates, black pigment of metal oxides, and glass having low melting point. Therein the filler content shall be 30-55% by weight while black pigment content 10-15% by weight, and thereby the stresses applied during baking of the spacer are shared by the filler and pigment so as to prevent spacer severance. The black pigment can enhance the contrast ratio.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to plasma display panels, and more particularly to the composition of spacers thereof.

0002

2. Description of the Related Art As shown in FIG. 3, a conventional display panel of this type includes a front glass substrate 1 having a transparent electrode 2 covered with a transparent dielectric layer 3 and a protective layer 8; A rear glass substrate 5 having an electrode 6 covered with a dielectric layer 7 and a protective layer 8 is arranged so that the transparent electrode 2 and the electrode 6 face each other with a discharge space 9 between them. After the periphery is hermetically sealed with a sealing glass 10, the discharge space 9 is evacuated to a vacuum, and is further filled with a dischargeable rare gas such as Ne.

When the display panel is of a glass XY dot matrix type, the discharge space 9 is formed on one or both of the transparent dielectric layer 3 and the dielectric layer 7, at right angles to the transparent electrode 2 and the electrode 6. The substrates are formed by bank-shaped spacers 4 provided so as to face each other so that both spacers 4 intersect orthogonally to each other, forming a matrix shape. The transparent electrode 2 and the electrode 6 are drawn out to the outside of the seal glass 10 and connected to an external drive circuit board with a metal lead, FPC, or the like. A scanning-side high-frequency pulse voltage is applied to the electrode 6 from the drive circuit, and a data-side high-frequency pulse voltage corresponding to the display data signal is applied to the transparent electrode 2, causing a desired discharge space to discharge and emit light to obtain a desired display pattern.

[0004] At this time, the above-mentioned spacer 4 acts as a barrier against the discharge, prevents the discharge from spreading to an undesired area, and has the effect of suppressing discharge crosstalk with neighboring electrodes. Spacers are usually made of a paste made of oxide ceramic fillers such as alumina and zirconia, black pigments made of oxides such as copper, chromium, iron, nickel, and cobalt, and low softening point glass powder with an organic binder. It is printed using a printing method and then fired.

[0005]

[Problems to be Solved by the Invention] In this conventional plasma display panel, the lower transparent dielectric layer 3 and dielectric layer 7 are removed during the baking process after screen printing of the spacers.
softens and flows, and as a result, tensile stress is applied to the spacer 4, which may cause the spacer to break and become missing over a width of several microns to a hundred and several tens of microns. There is a problem that the effect is lost and adjacent discharge cells emit light, resulting in erroneous lighting, or that light leaks to adjacent discharge cells.

[0006]

[Means for Solving the Problems] The present invention comprises a plurality of glass substrates facing each other with a predetermined gap between them by spacers, the periphery of the glass substrates being sealed, and the inside of the glass substrates being filled with a rare gas capable of discharging. In the plasma display panel, the spacer is a mixed sintered product of a filler made of fine particles of oxide ceramic, a black pigment, and a low softening point glass, and the weight composition ratio of the filler in the spacer is 30%.
55% to 55%, the weight composition ratio of black pigment is 10% to 15%
It is characterized by

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings. FIG. 1 is a sectional view of a plasma disk panel according to a first embodiment of the present invention. Front glass substrate 1 has a thickness of 1.8 mm
A transparent electrode 2 is formed on a soda glass plate with a thickness of about 1 μm by CVD method.
A transparent dielectric layer 3 is formed to a thickness of 10 to 20 μm after firing by a screen printing method so as to cover the transparent electrode 2. Next, spacers 4 are formed in a bank-like manner in a direction perpendicular to the transparent electrode 2 by the same screen printing method, with a film thickness of 10 to 1
00 μm. At this time, the spacer 4 contains 30 to 55 wt% of fine alumina powder and 1 of the black pigment of metal oxide.
0 to 15 wt%, and the remaining component is low softening point glass. Further, on the transparent dielectric layer 3, a protective layer 8 made of a magnesium compound is formed to a thickness of 0.5 to 3 μm by a spray method,
Perform firing.

On the other hand, the rear glass substrate 5 has a thickness of 1.8 mm.
A silver paste is formed on a soda glass plate by a screen printing method to a film thickness of 10 μm after firing, and is fired to form a striped electrode 6. Next, a dielectric layer 7 is formed to cover the electrode 6.
is formed to a film thickness of 10 to 20 μm after firing using a screen printing method. Further, a bank-like spacer 4 is formed in a direction perpendicular to the electrode 6 by screen printing to a film thickness of 10 to 100 μm after firing. The components and component ratios of the spacer 4 at this time are the same as those of the spacer 4 formed on the front glass substrate 1 described above. Thereafter, a protective layer 8 made of a magnesium compound is formed to a thickness of 0.5 to 3 μm by a spray method and fired.

Before forming the protective layer 8, the sealing glass 10 is previously formed on either or both of the front glass substrate 1 and the rear glass substrate 5 by a screen printing method, surrounding the discharge display area. 1 and the rear glass substrate 5 are placed facing each other so that the transparent electrode 2 and the electrode 6 are perpendicular to each other, that is, the spacers 4 are perpendicular to each other, and after fixing with clips or the like, they are heated and sealed, and the inside of the sealing glass 10 is evacuated. After evacuating the tank, it was filled with neon and a plasma display panel was manufactured.

FIG. 3 is a sectional view of a conventional plasma display panel, and its structure is similar to that of the first embodiment of the present invention shown in FIG.
The structure is the same as that of the embodiment shown in FIG.
becomes.

[0011] In the spacer having the composition of the present invention, even when the underlying transparent dielectric layer or dielectric layer softens and flows during spacer firing, the tensile stress applied to the spacer is reduced by the use of an appropriate amount of filler and pigment. It is dispersed and does not lead to disconnection of the spacer. In addition, the appropriate amount of pigment ensures that the discharge lighting areas and non-lighting areas are visually dispersed.
Contrast ratio increases. Experiments have shown that when the filler composition is less than 30 wt %, spacer disconnections significantly increase. This is because there is less filler, so the bank-like spacers are bonded more strongly to the low softening point glass, making it difficult for the stress applied during firing to be dispersed.As a result, the spacer is weaker in physically weak areas, such as thinner areas. This is thought to be due to it breaking. On the other hand, if the amount of filler is greater than 55 wt%, dispersion by the filler will be obtained and spacer breakage will be less likely to occur, but as the amount of filler increases, the strength of the spacer after firing will be weakened, and the spacers will only rub against each other. It will collapse. Therefore, the amount of filler in the spacer is 30wt
% to 55wt%.

[0012] Also, the amount of black pigment should be more than 10 wt% to increase the contrast ratio, and conversely the amount should be more than 15 wt%.
If it exceeds wt%, separation will occur due to the difference in specific gravity between the filler in the spacer and the low softening point glass, and a composition difference between the upper and lower portions of the spacer will occur due to sedimentation of the black pigment, making wire breakage more likely. Furthermore, since black pigments generally have a small particle size, they penetrate between filler particles and strengthen the bonds between the particles, increasing the strength of the spacer, making it less likely to break, and increasing the contrast ratio. Therefore, the amount of black pigment in the spacer is between 10wt% and 15wt%.
wt%.

FIG. 2 shows a cross-sectional view of a plasma display panel according to a second embodiment of the present invention. This second embodiment is characterized in that the spacer 4 is provided only on the front glass substrate 1, and the spacer 4 is provided on the rear glass substrate 5.
is not provided. This embodiment has the advantage that by increasing the thickness of the spacer 4, the step of providing the spacer 4 on one side, that is, on the rear glass substrate side, can be omitted.

It goes without saying that the present invention can also be applied to a color plasma display panel that emits light by coating the inside of the panel with a phosphor.

[0015]

Effects of the Invention As explained above, the present invention allows the amount of the filler made of oxide ceramics contained in the spacer to be 30 wt% to 55 wt%, and the amount of the black pigment made of metal oxide to be 10 wt% to 15 wt%. By doing so, the stress applied during firing of the spacer is dispersed, so that the spacer does not break, and the strength of the spacer after firing is also increased. According to experiments,
In the spacer having the composition of the present invention, no disconnection of the spacer occurred at all. Furthermore, it also has the effect of increasing the contrast ratio due to the black pigment. In such a plasma display panel, the effect of the spacer as a barrier rib is not lost, and adjacent discharge cells do not emit light or light leaks to adjacent discharge cells.

[Brief explanation of the drawing]

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

FIG. 2 is a sectional view showing a second embodiment of the invention.

FIG. 3 is a sectional view showing a conventional example.

[Explanation of symbols]

1 Front glass substrate 2 Transparent electrode 3 Transparent dielectric layer 4 Spacer 5 Rear glass substrate 6 Electrode 7 Dielectric layer 8 Protective layer 9 Discharge space 10 Seal glass

Claims (1)

[Claims] 1. A plasma display panel in which a plurality of glass substrates face each other with a predetermined gap between them, the periphery of the glass substrates is sealed, and the inside is filled with a rare gas capable of discharging, wherein the spacer is It is a mixed sintered product of a filler made of fine particles of oxide ceramics, a black pigment made of a metal oxide, and a low softening point glass, and the weight composition ratio of the filler in the spacer is 30% to 55%, and the weight of the black pigment. A plasma display panel characterized in that the growth ratio is 10% to 15%.