JPH1167105A - Color plasma display panel and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a color filter layer for improving the contrast of a screen board having an opening width sufficient, even for an exactly fine pattern through separating by layer of a red color absorbing layer, a green color absorbing layer and a blue color absorbing layer of a filter layer with a transparent dielectric layer, and laminating them. SOLUTION: A filter layer 4 is formed on a transparent dielectric layer 3a, and a transparent dielectric layer 3b to be bonded with a barrier rib 7 is laminated on the filter layer 4. In the filter layer 4, a cell C for emitting red light is formed with a green light absorbing layer 4c and a blue light absorbing layer 4a, and a cell C for emitting the green light is formed with a red light absorbing layer 4b and a blue light absorbing layer 4a, and a cell C for emitting the blue light is formed with a red light absorbing layer 4b and a green light absorbing layer 4c. With this structure, since one cell C is formed with two of each color absorbing layers 4a, 4b, 4c, even in the case where cell pitch is becomes narrow, each color-absorbing layer 4a, 4b, 4c can be formed through a screen board having an opening width which is twice that of the cell pitch.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color plasma display panel used for a display device and the like and a method of manufacturing the same, and more particularly, to a red, green and blue phosphor and a filter layer having transparency for each emission color. And a method of manufacturing the same with high contrast.

[0002]

2. Description of the Related Art A color plasma display panel (hereinafter abbreviated as "display panel") basically has a structure shown in FIG.
As shown in FIG. 7, a flat front substrate A and a rear substrate B are arranged in parallel at an interval, and both A and B are held at a fixed interval by a partition wall 7, and a cell C is formed between the partition walls 7. It has a structure. The front substrate A is a side on which light is extracted, and a striped scanning electrode 2 is provided on the back surface of the insulating substrate 1 such as transparent glass, which is transparent to visible light, facing the rear substrate B.
Are formed on the paper surface in the left-right direction. On the back substrate B, an insulating substrate 5 such as transparent glass that transmits visible light is formed on the back surface facing the front substrate A, and stripe-shaped write electrodes 6 are formed from the back surface of the paper to the surface direction. Therefore, the stripe-shaped electrodes 2 and 6 of the front substrate A and the rear substrate B have a positional relationship in the orthogonal direction.

Further, a transparent dielectric layer 3 for electrically insulating the scan electrodes 2 is laminated on the scan electrodes 2 formed on the front substrate A. On the partition walls 7 between the cells C, there are formed ultraviolet-excited phosphors 8 having emission colors corresponding to the three primary colors of light, red, green and blue.

In such a display panel,
Color display is performed by controlling discharge in each cell C and changing the emission intensity of each emission color.
At this time, in order to prevent adjacent phosphors 8 of different emission colors in a non-selected state from emitting light, the partition walls 7 are formed by multi-layer printing of a thick film printing method or the like, and the cells C for each color are partitioned. Have been.

When the phosphor 8 is formed on the partition walls 7 for colorization, the body color of the phosphor particles is almost white or light gray, so that light is emitted when external light is applied to the panel. There is a problem that the contrast between display dots and non-display dots that do not emit light becomes unclear, and display contrast deteriorates. In order to suppress the reflection of external light on the panel surface, there is also a method of installing a filter plate having uniform absorption characteristics over the entire visible wavelength range on the front surface of the panel. However, such a filter plate also absorbs light emitted from the phosphor from the inside of the display panel, which causes a problem that the luminance and the efficiency are reduced.

Therefore, an AC type display panel as shown in FIGS. 6 and 7 is disclosed in Japanese Patent Laid-Open No. 4-36930. The AC display panel shown in FIG. 6 has a structure in which a colored dielectric layer 10 is laminated on the scanning electrodes 2 of the insulating substrate 1 constituting the front substrate A. Colored dielectric layer 10
Is to form a blue light transmitting filter in a cell forming a red light emitting phosphor, a green light transmitting filter in a cell forming a green light emitting phosphor, and a blue light transmitting filter in a cell forming a blue light emitting phosphor. .

The AC display panel shown in FIG. 7 has a structure in which a filter layer 11 and a transparent dielectric layer 3 are laminated on a scanning electrode 2 of an insulating substrate 1 constituting a front substrate A. The red, green, and blue colors are transmitted for each cell C partitioned by.

Further, a DC type display panel as shown in FIG. 8 is disclosed in Japanese Patent Laid-Open No. 4-1202. In the DC display panel, the scanning electrodes 2 on the insulating substrate 1 constituting the front substrate A are not covered with a dielectric layer, and a color filter layer 12 having a black matrix is laminated on the entire back surface of the insulating substrate 11. Tier 1
The scanning electrode 2 is formed for each cell C on the scanning electrode 2, and the phosphor 8 is laminated on the scanning electrode 2.

A red light transmitting filter layer 12 is formed on the cell C on which the red light emitting phosphor 8 is formed, and a green light transmitting filter layer 12 is formed on the cell C on which the green light emitting phosphor 8 is formed. By forming a color filter layer 12 corresponding to the emission color of each phosphor 8 in each cell C, such as a blue light transmitting filter layer 12, in the cell C in which the cells 8 are formed, without lowering the luminance efficiency. The contrast can be increased.

The color filter layer 12 is generally formed by mixing and pasting pigment powder having desired transmission characteristics with low-melting glass and applying the paste by screen printing.
In the screen printing method, the paste is applied in a pattern by applying an emulsion to a mesh in which fine lines are knitted and discharging the paste with a squeegee from the opening where the emulsion is not applied, using a screen stencil with a pattern formed. is there. For example, as shown in FIG.
The bias angle is set to 30 ° using a screen mesh M having a diameter of 400 μm and a count of 400, and patterns of 100 μm and 80 μm can be drawn.

A method of forming a color filter on a substrate for a plasma display, which is excellent in heat resistance, has no outgassing, and can improve resolution and processing accuracy, is disclosed in JP-A-6-5202. Have been.

[0012]

SUMMARY OF THE INVENTION Color filter layer 12
In the above-described screen printing method for forming a screen mesh, the screen mesh M is used. Therefore, there are actually thin lines forming the screen mesh M in the opening for discharging the paste. When the opening is large, the closing of the pattern by the screen mesh M is not so problematic.

However, at present, high-density video information is required in various usage forms, and a large-area and high-definition display is also required for a plasma display panel. Therefore, as the pattern becomes smaller and the pattern width becomes narrower, the influence of the mesh on the printed pattern cannot be ignored, and the color filter layer 12 with high accuracy cannot be formed.

That is, in the screen plate S shown in FIG. 9, an opening of about 20% is secured in the width direction even in the X portion where the opening is most closed when the width is 100 μm, for example. A stable discharge of the paste can be obtained. However, since the screen mesh exists so as to substantially cover the width direction of the pattern in the Y portion having a width of 80 μm, the discharge amount of the paste is reduced and a continuous pattern cannot be drawn. As described above, it is difficult to draw a pattern of 100 μm or less by screen printing, and the color filter layer 12 cannot be formed with high accuracy.

There is also a method in which a single filter pattern is formed for each of red, green and blue colors by photolithography using a photosensitive filter material.
There are problems that the process becomes complicated and that the use efficiency of the material is poor.

Accordingly, the present invention provides a color plasma display capable of forming a color filter layer for improving contrast by using a screen plate having a sufficient opening width even with a high-definition pattern, and its manufacture. The aim is to provide a method.

[0017]

The color display panel of the present invention has a transparent write electrode in a stripe shape for each of red, green, and blue light-emitting cells formed on the back surface of an insulating substrate that is transparent to visible light. A transparent scanning electrode is formed in a stripe shape in a direction perpendicular to the writing electrode on the back surface of a visible light transmitting insulating substrate which is disposed in parallel with a space on the back surface side of the back substrate formed on the back substrate. A transparent dielectric layer that electrically insulates the scan electrode is formed on the scan electrode, and a green light absorption layer and a blue light absorption layer are formed on the dielectric layer at the position of the red light emitting cell. Forming a red light absorbing layer and a blue light absorbing layer at the position of the green light emitting cell, and forming a red light absorbing layer and a green light absorbing layer at the position of the blue light emitting cell to selectively transmit visible light. Form a transparent filter layer and fill A front substrate in which a transparent dielectric layer is laminated on the layer, holding the insulating substrate of the back substrate and the dielectric layer on the filter layer of the front substrate, a red light emitting cell, a green light emitting cell and a blue light emitting cell. And a large number of partition walls that partition each cell.

According to the present invention, since the filter layer forms one light absorbing layer for two cells, even if the pattern becomes smaller and the cell pitch becomes narrower, the cell pitch becomes 2 times.
The green, blue and red light absorbing layers can be formed by the screen plate having the double opening width.

Each of the red light absorbing layer, green light absorbing layer and blue light absorbing layer of the filter layer may be separated and laminated by a transparent dielectric layer.

It is preferable that the blue light absorbing layer of the filter layer contains at least lead chromate. The red light absorbing layer of the filter layer preferably contains at least cobalt-tin oxide. The green light absorbing layer of the filter layer preferably contains at least cobalt phosphate.

According to the method of manufacturing a color plasma display of the present invention, (1) transparent scanning electrodes are formed in stripes on the back surface of a visible light transmitting insulating substrate which is arranged in parallel on the back surface of the back substrate at intervals. Forming, (2) laminating a dielectric layer for electrically insulating the scan electrode on the scan electrode, and (3) forming a red light emitting cell and a green light emitting cell with a blue light absorbing layer on the dielectric layer. At the same time, forming a red light absorbing layer at the same time as the green light emitting cell and the blue light emitting cell, and simultaneously forming the green light absorbing layer at the same time as the blue light emitting cell and the red light emitting cell, And a step of forming a filter layer that selectively transmits light through the filter, and the steps are performed in the order of (1) to (3).

According to the present invention, since the filter layer forms one light absorbing layer in two cells, the pattern becomes small and has an opening width twice as large as the cell pitch even when the cell pitch becomes narrow. Green, depending on screen version
Blue and red light absorbing layers can be formed.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of a color plasma display according to the present invention will be described below with reference to FIG.
In the color plasma display according to the present invention, the front substrate A and the rear substrate B, which are arranged in parallel at intervals, are held by a large number of partitions 7, and each of the red, green, and blue light emission is provided by the multiple partitions 7. A cell C is formed.

On the front substrate A, a stripe-shaped transparent scanning electrode 2 is formed on the back surface of an insulating substrate 1 such as transparent glass, which is transparent to visible light, facing the rear substrate B, in the horizontal direction of the drawing. A transparent dielectric layer 3a that electrically insulates the scanning electrode 2 is laminated thereon, a filter layer 4 is formed on the dielectric layer 3a, and a transparent dielectric layer is formed on the filter layer 4 and joined to the partition 7 described above. It is obtained by stacking layers 3b. The filter layer 4 forms a green light absorbing layer 4c and a blue light absorbing layer 4a in a red light emitting cell C, and forms a red light absorbing layer 4b and a blue light absorbing layer 4a in a green light emitting cell C, and emits blue light. In the cell C, a red light absorbing layer 4b and a green light absorbing layer 4c are formed.

Therefore, two light absorbing layers 4a, 4b and 4c of each color are formed for one cell C. For this reason, even if the cell pitch becomes narrow, the light absorbing layer 4 of each color is formed by a screen plate having an opening width twice as large as the cell pitch.
a, 4b and 4c can be formed.

As the blue light absorbing layer, lead chromate (PbCrO
₄ ) powder, a red light absorbing layer of cobalt oxide-tin (CoO.SnO ₂ ) powder, a green light absorbing layer of cobalt phosphate (Co ₃ (PO ₄ ) ₂ ) powder, and a cellulose binder. And a paste mixed with a solvent.
Lead chromate has a large absorption for visible light having a wavelength of 480 nm or less, cobalt oxide-tin has a large absorption for light in a wavelength range of 560 to 680 nm, and cobalt phosphate has a large absorption for a light of 480 to 580 nm. It has large absorption for light in the wavelength range.

As a result, in a green light emitting cell in which a blue light absorbing layer and a red light absorbing layer are stacked, a wavelength range of 480 to 560 nm corresponding to green light emission is selectively transmitted, and the red light absorbing layer and the green light In a blue light emitting cell with an absorption layer laminated, 480
The wavelength region corresponding to blue light emission of nm or less is selectively transmitted, and further, in a red light emitting cell in which a green light absorbing layer and a blue light absorbing layer are laminated, the wavelength region corresponding to red light emission of 580 nm or more is selectively transmitted. Become so.

On the other hand, the back substrate B is a back surface where the insulating substrate 5 such as transparent glass which transmits visible light is opposed to the front substrate A, and the stripe-shaped write electrodes 6 It is formed from the back side to the front side. The write electrode 6, the insulating substrate 5, and the partition 7
Sequentially, blue, red and green phosphors 8a, 8
b, 8c are stacked to form red, green, and blue light emitting cells C.

Next, a method of manufacturing a plasma display according to the present invention will be described with reference to FIG. First, a method for forming the front substrate A will be described. First, a transparent conductive film made of tin oxide-indium oxide (ITO) is formed on the entire back surface of the insulating substrate 1 by a sputtering method.
Further, the ITO film is etched by photolithography and nitric acid to form scanning electrodes 2 in the form of stripes in the horizontal direction on the paper. Subsequently, a low-melting glass paste is applied by screen printing so as to cover the entire display portion of the display panel, and baked at 600 ° C.
A transparent dielectric layer 3a is formed.

Next, the filter layer 4 is formed on the dielectric layer 3a. As shown in FIG. 2, the filter layer 4 is formed by using a screen plate S to form a blue light absorbing layer 4a on a portion corresponding to each of red and green cells C in a stripe shape from the back side to the front side of the drawing. To be formed. The screen plate S is formed by forming openings t having a width corresponding to two cells C in a stripe shape at a pitch corresponding to three cells C.

Subsequently, similarly, a red light absorbing layer 4b is coated and formed on portions corresponding to the cells C for emitting green light and blue light. Thereby, in the cell C emitting green light, the blue light absorbing layer 4
a and the red light absorbing layer 4b are laminated. Further, by applying and forming the green light absorbing layer 4c on the portion corresponding to each of the cells C for emitting blue light and red light, the blue light absorbing layer 4a and the green light absorbing layer 4c are stacked in the cell C for emitting red light. In the cell C emitting blue light, the red light absorbing layer 4b is used.
And the green light absorbing layer 4c are laminated.

Next, a low-melting glass paste is applied to the entire display area and baked at 600 ° C. to obtain the filter layer 4 and the transparent dielectric layer 3b. Further, a magnesium oxide (MgO) layer (not shown) is formed in the display region by a vacuum evaporation method, and the formation of each layer on the insulating substrate 1 is completed.

On the other hand, on the back substrate B, stripe-shaped write electrodes 6 are formed on the back surface of an insulating substrate 5 such as glass, which is transparent to visible light, in a direction perpendicular to the write electrodes 6 of the front substrate A. Then, a large number of partition walls 7 are provided between the write electrodes 6 on the back surface of the insulating substrate 5. Thereafter, the blue phosphor layer 4a, the red phosphor layer 4b, and the green phosphor layer 4c are formed on the surfaces of the write electrode 6, the back substrate 5, and the partition 7, respectively.
To form Thereafter, a frit glass layer for sealing (not shown) is formed around the back substrate B.

Finally, the rear surfaces of the front substrate A and the rear substrate B are opposed to each other in parallel with a space between them, and are combined at predetermined positions so that the partition wall 7 holds the front substrate A and the rear substrate B, and After the interior is evacuated and sealed with a discharge gas, a plasma display is completed.

Next, another method of forming the front substrate A of the plasma display panel will be described with reference to FIG. In this manufacturing method, first, a scanning electrode 2 and a transparent dielectric layer 3a are laminated on an insulating substrate 1. Next, as shown in FIG. 3A, a black mask 9 for dividing the cells C for each emission color is formed. The black mask 9 is formed, for example, by mixing a black pigment and a low-melting glass paste and applying the paste to the entire display area.
Can be formed by forming a resist layer only on the portion where the is to be formed and patterning it by a sandblast method.

Next, as shown in FIG. 3B, the blue light absorbing layer paste 14 is pressed into the red light emitting cell C and the green light emitting cell C by a screen printing method and applied.
At this time, by increasing the solvent content of the blue light absorbing layer paste 14 and lowering the viscosity, even if the openings of the screen plate S are biased, the paste can be pressed evenly into the region sandwiched between the black masks. it can.

After applying the blue light absorbing layer paste 14,
After drying, as shown in FIG.
Obtain a. Similarly, a red light absorbing layer 4b and a green light absorbing layer 4c are formed. Thus, as shown in FIG. 3D, the blue light absorbing layer 4a and the green light absorbing layer 4c in the red light emitting cell C, and the blue light absorbing layer 4a in the green light emitting cell C.
And the red light absorbing layer 4b, and in the cell C emitting blue light, the filter layer 4 in which the red light absorbing layer 4b and the green light absorbing layer 4c are respectively laminated is formed. On the insulating substrate 1, a transparent dielectric layer 3b (see FIG. 1) is further formed over the entire display area. Thereafter, by baking at 600 ° C., the filter layer 4 having desired transmission characteristics separated by the black mask 9 is formed.

Next, another method of forming the front substrate A of the plasma display panel will be described with reference to FIG. In this method, first, a scanning electrode 2 and a transparent dielectric layer 3a are formed on an insulating substrate 1 such as transparent glass. Next, the red light-emitting cell 4 and the green light-emitting cell C are provided with the blue light absorbing layer 4a, the transparent dielectric layer 3c is provided over the entire display area, and the green light-emitting cell C and the blue light-emitting cell C are provided with the red light absorbing layer 4a.
b, the transparent dielectric layer 3d over the entire display area, the green light absorbing layer 4c over the blue light emitting cell C and the red light emitting cell C,
A transparent dielectric layer 3b is formed over the entire display area.

Thereafter, by firing at 600 ° C.,
Filter layer 4 and transparent dielectric layers 3a, 3b, 3c, 3d
Is formed. With the above configuration, the red, green and blue light absorbing layers 4a, 4b and 4c are
a, 3b, 3c, 3d, so that they do not come into direct contact. Even in such a configuration, a filter layer having a transmission characteristic according to the emission color in each cell C can be formed by combining the red, green, and blue light absorbing layers 4a, 4b, and 4c.

The present invention is not limited to the above-described embodiment, and various changes can be made within the scope of the technical matters described in the claims.

[0041]

According to the present invention, since the filter layer forms one light absorbing layer for two cells, even if the cell pitch becomes narrow, the screen plate having an opening width twice as large as the cell pitch makes it possible to form the filter layer in green. , Blue and red light absorbing layers can be formed. Therefore, a filter layer can be formed using a screen printing method even for a highly detailed pattern. As a result, the color plasma display manufactured by this method can provide high-density video information.

Further, according to the method shown in FIGS. 2 and 3, since the filter layer to be formed is formed at the same time as the adjacent cells, the same as in the conventional case where the filter layer is formed independently in each cell. All the filter layers can be formed in one printing. Therefore, the productivity is improved by this method. Further, in the case where a change occurs in the transmission characteristics due to baking while the different types of filter layers are in contact with each other, a transparent dielectric layer is formed between the filter layers as shown in FIG. The mutual influence of the filter layers can be eliminated.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a color plasma display panel according to the present invention.

FIG. 2 is a schematic view showing a manufacturing process of the color plasma display shown in FIG.

FIG. 3 is a schematic view showing another manufacturing process of the color plasma display panel according to the present invention, which is different from FIG. 2;

FIG. 4 is a schematic view showing another manufacturing process of the color plasma display panel according to the present invention, which is different from FIGS. 1 and 2;

FIG. 5 is a sectional view of a main part of a conventional color plasma display panel.

FIG. 6 is a cross-sectional view of a main part of a conventional AC plasma display panel.

FIG. 7 is a cross-sectional view of a main part of a conventional AC plasma display panel different from FIG.

FIG. 8 is a cross-sectional view of a main part of a conventional DC plasma display panel.

FIG. 9 is a schematic view of a screen plate used for screen printing.

[Description of Signs] A: Front substrate B: Back substrate C: Cell 1: Insulating substrate 2: Scan electrode 3a: Dielectric layer 3b: Dielectric layer 4: Filter layer 4a: Blue light absorbing layer 4b: Red light absorbing layer 4c: green light absorbing layer 5: insulating substrate 6: writing electrode 7: partition wall 8a: blue phosphor 8b: red phosphor 8c: green phosphor

Claims (6)

[Claims] 1. A back substrate in which transparent write electrodes are formed in stripes for each of red, green, and blue light-emitting cells formed on the back surface of an insulating substrate that is transparent to visible light, and a back surface of the back substrate. A transparent scanning electrode is formed in a stripe shape in a direction orthogonal to the writing electrode on the back surface of a visible light transmitting insulating substrate arranged in parallel at an interval on the side, and the scanning electrode is electrically connected to the scanning electrode. A transparent dielectric layer for insulating coating is laminated on the dielectric layer. On the dielectric layer, a green light absorbing layer and a blue light absorbing layer are formed at a position of a red light emitting cell, and a red light absorbing layer is formed at a position of a green light emitting cell. Forming a transparent and selectively transmitting visible light filter layer in which a red light absorbing layer and a green light absorbing layer are formed at positions of blue light emitting cells, wherein A front substrate on which a transparent dielectric layer is laminated A partition that holds the insulating substrate of the rear substrate and the dielectric layer on the filter layer of the front substrate, and partitions the cells into red, green, and blue cells. Color plasma display panel. 2. The color according to claim 1, wherein the red light absorbing layer, the green light absorbing layer, and the blue light absorbing layer of the filter layer are separately laminated by a transparent dielectric layer. Plasma display panel. 3. The color plasma display panel according to claim 1, wherein the blue light absorbing layer of the filter layer contains at least lead chromate. 4. The color plasma display panel according to claim 1, wherein the red light absorbing layer of the filter layer contains at least cobalt-tin oxide. 5. The color plasma display panel according to claim 1, wherein the green light absorbing layer of the filter layer contains at least cobalt phosphate. 6. A step of: (1) forming transparent scanning electrodes in a stripe pattern on the back surface of a visible light-transmitting insulating substrate disposed in parallel with a gap on the back surface of the back substrate; (3) laminating a dielectric layer for electrically insulating the scan electrode on the scan electrode; and (3) simultaneously forming a blue light absorbing layer in a red light emitting cell and a green light emitting cell on the dielectric layer, A filter that is transparent and selectively transmits visible light by forming a red light absorbing layer simultaneously with the blue light emitting cell and the blue light emitting cell, and simultaneously forming a green light absorbing layer simultaneously with the blue light emitting cell and the red light emitting cell A method for manufacturing a color plasma display panel, comprising: forming a layer; and performing the steps in the order of (1) to (3).