JP2000268728A - Plasma display panel and image display device using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve luminance and a luminance life of a phosphor layer of a plasma display panel. SOLUTION: A phosphor layer of this plasma display panel is formed by attaching at least one of metal oxide fine particles containing at least one of Al, Zn, In, Ga, Ge, and Bi and diamond fine particles as modifying material for improving luminance on a surface of a phosphor particle or by mixing with the phosphor particle in a matrix of the phosphor layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a plasma display panel (hereinafter abbreviated as PDP) and a display device using the same.

[0002]

2. Description of the Related Art A PDP is a thin and large-sized display device, and is expected to replace a CRT or the like. This plasma display uses a vacuum ultraviolet ray generated in a minute discharge space containing a rare gas as an excitation source and emits light from a phosphor disposed in the discharge space to perform color display.

FIG. 2 is a schematic view of a display panel in a PDP. The display panel is composed of the front substrate 1 shown in FIG.
This is a structure in which the back substrate 5 of FIG. As shown in FIG. 2A, a front substrate (glass plate) 1 has display electrodes 2 formed in parallel at regular intervals,
A dielectric layer 3 and a protective film 4 are formed.

On the back substrate 5 shown in FIG. 2 (b), address electrodes 6 arranged orthogonal to the display electrodes 2 on the front substrate 1 and a discharge space 7 are kept to isolate discharge pixels. And red, green, and blue phosphor layers 9R, 9G, and 9B, which are sequentially applied in stripes so as to cover the groove surfaces between the partitions 8, respectively. These phosphor layers 9 are formed by mixing a phosphor and a vehicle to form a phosphor paste, forming the paste by screen printing or the like, and removing the volatile components by firing.

The front substrate 1 and the rear substrate (glass plate) 5 are sealed to form a discharge space 7, in which a discharge gas (not shown) is sealed. As the discharge gas, a rare gas such as a mixture of Ne and Xe or a mixture of He and Xe is used. When a voltage is applied between the display electrode 2 and the address electrode 6, plasma discharge is caused in the sealed rare gas, and vacuum ultraviolet rays having a wavelength of 200 nm or less are emitted. Among these ultraviolet rays, Xe resonance lines (center wavelength: 147 nm) and Xe molecular beams (center wavelength: 172 nm) mainly excite the phosphor,
The phosphor emits visible light R (red), G (green), and B (blue) to realize color display.

[0006] Japanese Patent Application Laid-Open No. 8-319483, for example, relates to this type of technology.

[0007]

Problems to be Solved by the Invention In PDPs, there has been a problem of improving the emission luminance and extending the life of the device, and the development of phosphor materials has been promoted in order to solve these problems. However, the brightness of the current PDP is about 450 Cd / m ² , and the brightness of a direct-view electron tube color television (600 to
It is lower than 1000 Cd / m ² ), and further improvement in luminous efficiency and luminance is desired. Further, there is a demand for further improvement in life characteristics.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned conventional problems. By further improving the emission luminance of a phosphor in a PDP and the life characteristics thereof, the present invention is significantly improved. And a display device using the same.

The term "luminance" used in the present invention will be explained. Strictly speaking, the improvement of the luminance at the beginning of use of the plasma display panel is referred to as "initial value luminance improvement". The improvement of the luminance is referred to as the improvement of the emission luminance maintenance ratio (the same as the improvement of the life characteristic, that is, the extension of the life). The difference between the two is whether or not there is a certain elapsed time during the luminance measurement. Since this means improvement in light emission luminance, in a broad sense including both of them, it is simply referred to as improvement in light emission luminance.

[0010]

In order to achieve the above object, the present inventors have developed a plasma display panel having a light emitting region including at least a partition wall surface, which constitutes a main part of a discharge space filled with a rare gas. About the formed phosphor layer,
After various experimental studies, at least one of the specific metal oxide and diamond particles was adhered to the surface of the phosphor particles constituting the phosphor layer, or mixed together with the phosphor particles in the phosphor layer, Light emission brightness of plasma display panel (initial value or brightness maintenance rate)
Has obtained a new finding that it is significantly improved.

The present invention has been made based on such knowledge, and a plasma display panel which can achieve the above object of the present invention comprises a front substrate having a plurality of display electrodes, and a plurality of address electrodes. A back substrate having a partition wall between the address electrodes and opposing each other to form a side wall as a side wall, and a groove having at least the address electrode surface as a bottom surface and a phosphor layer formed on a wall surface of the groove. A plasma display panel having a discharge gas sealed in a space formed by combining and sealingly fixing the front substrate and the rear substrate, wherein at least one of Al, Zn, In, Ga, Ge and Bi is provided. The phosphor as at least one selected from metal oxide fine particles containing at least one type and diamond fine particles as a luminance improving and modifying material; Or adhere to the surface of phosphor particles constituting the, or is characterized in that the mix with the phosphor particles in a matrix of the phosphor layer.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The introduction of the above-mentioned luminance improving and modifying material into a phosphor layer is effective in common to any of the R, G and B phosphor layers. If applied to a display device, an image display device with dramatically improved luminance characteristics can be realized.

FIG. 1 is an enlarged cross-sectional view schematically showing a main part of a plasma display panel according to the present invention, in which a phosphor layer is formed on a rear substrate (glass plate) 5 side. On the inner wall surface of the groove formed by the partition wall 8 provided on the back substrate 5 and the bottom surface including the address electrodes 6, a phosphor 9 modified with a brightness improvement modifying material 10 is coated with a known coating technique such as printing. A predetermined phosphor layer is provided through a baking process that is formed and removes unnecessary organic components and the like used during coating.

As the luminance improving and modifying material, those having an average particle size considerably smaller than that of the phosphor particles, for example, those having about 1/10 or less of the phosphor particles are used. When the phosphor layer is formed, the phosphor layer is preferably introduced in a weight ratio of 0.1 to 5 wt%. However,
In the case of diamond fine particles, 0.5 to 5 wt% is more preferable.

If the amount is less than 0.1% by weight, the improvement in luminance is insufficient. If the amount exceeds 5% by weight, the amount of light absorbed by the phosphor cannot be ignored. % Is preferred.

Further, Al, Zn, an In, Ga, in the Ge and metal oxide fine particles containing at least one of Bi, in particular oxides of Al and Zn Preferably, for example, Al ₂
O ₃ , ZnO, and a mixture of ZnO—Al ₂ O _3. These oxides have an improved luminance initial value and thus a luminance retention ratio. Further, in the case of diamond fine particles, the luminance maintenance ratio is improved rather than the improvement of the initial value of the luminance, which is effective in extending the life.

In the present invention, when forming the phosphor layer, the above-mentioned luminance improving and modifying material is simply mixed with the phosphor, or a phosphor particle coated on the surface thereof is used.
By using such a material for the phosphor layer, it is possible to realize a plasma display panel having higher luminous efficiency, higher luminance, and longer life than conventional materials, and an image display device using the plasma display panel.

[0018] the modified phosphor forming the red phosphor _{layer, YBO 3: Eu, Y 2} O 3: Eu, GdBO 3: E
u, (Y, Gd) (P, V) O ₄ : Eu, Y (P, V)
O ₄ : Eu, (Y, Gd) BO ₃ : Eu, ScBO ₃ : E
u, a phosphor for a CRT (Cathode Ray Tube), a lamp, or the like can be used.

The phosphor to be modified forming the green phosphor layer includes Zn ₂ SiO ₄ : Mn, BaAl ₁₂ O ₁₉ : Mn, YB
O ₃ : Tb, GdBO ₃ : Tb, a CRT, a phosphor for a lamp, or the like can be used.

The phosphor to be modified forming the blue phosphor layer includes BaMgAl ₁₄ O ₂₃ : Eu, BaMgAl ₁₀ O ₁₇ :
Eu, (Y, Gd) (P, V) O ₄ , CaWO ₄ : Pb,
Y ₂ SiO ₅ : Ce, a CRT, a phosphor for a lamp, or the like can be used.

FIG. 3 shows a method for obtaining a modified phosphor by modifying the above-mentioned phosphor to be modified with a luminance improving modifying material.
As schematically shown in FIG. 3A, a method of mixing the phosphor 9 and the brightness improving / modifying material 10 as shown in FIG.
A method of covering a part of the surface of the phosphor particles 9 with the brightness improvement modifying material 10, a method of covering the entire periphery of the surface of the phosphor particles 9 with the brightness improvement modifying material 10 as shown in FIG. be able to.

Further, the modified phosphor of the present invention is used in a red phosphor layer 9.
Which of R, green phosphor layer 9G, and blue phosphor layer 9B is used can be appropriately selected in consideration of white balance and the like.

[0023]

Embodiments of the present invention will be described below in detail with reference to the drawings. <Embodiment 1> FIG. 4 is an enlarged sectional view of a part of a rear substrate 5 of a display panel (a part where a red phosphor layer 9R is formed). After forming the address electrodes 6 and the barrier ribs 8 on the back substrate 5, a phosphor layer was formed. As the red phosphor, (Y,
Gd) BO ₃ : Eu and Zn ₂ Si as a green phosphor
O ₄ : Mn, and the blue phosphor is BaMgAl ₁₀ O ₁₇ :
Using Eu, any of these phosphors was modified using ZnO-Al ₂ O ₃ as the luminance improving modification material 10.

The method of forming each phosphor layer modified with the luminance improving modification material 10 is as follows, and has the structure shown in FIG. 3 (b). First, the same amount of ZnO and Al ₂ O ₃ are uniformly mixed as the luminance improving modifying material 10, and this is mixed in a weight ratio of 0.1 to 5.0% with respect to each color phosphor.
The surface of the phosphor particles of each color were deposited mixture of ZnO-Al ₂ O _3. The average particle size of each color phosphor is about 3 μm,
The average particle sizes of ZnO and Al ₂ O ₃ are both about 0.3 μm.

A phosphor paste is prepared by mixing 40 parts by weight of each color phosphor whose surface is modified with ZnO-Al ₂ O ₃ and 60 parts by weight of a vehicle. The obtained phosphor paste of each color is applied to the wall surface forming the discharge space 7 of the rear substrate 5 by screen printing, and the volatile components in the paste are removed and the organic substances are removed by burning by a drying and baking process. 9R, 9G and 9B were formed.

The rear substrate 5 is bonded to the front substrate 1 and a discharge gas (Ne-in this example, Ne-
Xe mixed gas was used) to produce a plasma display panel having the structure shown in FIG. 2, and the emission luminance characteristics (initial value) were measured with a known luminance meter. As a result, ZnO
By using the phosphor modified with -Al ₂ O ₃ , a brightness increase of about 15% was realized as compared with the comparative example using the phosphor without modification.

Example 2 A panel was manufactured in the same manner as in Example 1, and the same light emission luminance characteristics were measured. However, the red phosphor was modified with ZnO—Al ₂ O ₃ (Y
₂ O ₃ ): Eu was used. Also, the introduction of ZnO and Al ₂ O ₃ , which are the luminance improvement modifying materials 10, were mixed together with the phosphors of each color at the time of forming the paste. In this case, the modification status of each color phosphor with ZnO-Al ₂ O ₃ is shown in FIG.
As shown in FIG. Otherwise, a panel was manufactured in the same manner as in Example 1. As a result, we obtained the same effect as in Example 1, the comparative example which is not modified with ZnO-Al ₂ O _3, the brightness increase of 15% was achieved.

Example 3 In Example 1, the red phosphor was modified with ZnO—Al ₂ O ₃ (Y, Gd).
(P, V) O ₄ : Eu was used. A panel was manufactured in the same manner as in Example 1 except that a different red phosphor was used, and the same emission luminance characteristics were measured. As a result, an increase in luminance of about 15% was achieved as compared with the comparative example using the phosphor without modification.

Example 4 In Example 1, BaAl ₁₂ O ₁₉ modified with ZnO—Al ₂ O ₃ as a green phosphor:
Mn was used. Example 1 except that a different green phosphor was used.
A panel was produced in the same manner as in Example 1 and the same emission luminance characteristics were measured. As a result, an increase in luminance of about 15% was achieved as compared with the comparative example using the phosphor without modification.

Example 5 In Example 2, BaAl ₁₂ O ₁₉ modified with ZnO—Al ₂ O ₃ as a green phosphor:
Mn was used. A panel was prepared in the same manner as in Example 2 except that the green phosphor used was different, and the same emission luminance characteristics were measured. As a result, an increase in luminance of about 15% was achieved as compared with the comparative example using the phosphor without modification.

Example 6 In Example 3, BaAl ₁₂ O ₁₉ modified with ZnO—Al ₂ O ₃ as a green phosphor:
Mn was used. Example 3 except that a different green phosphor was used.
A panel was produced in the same manner as in Example 1 and the same emission luminance characteristics were measured. As a result, an increase in luminance of about 15% was achieved as compared with the comparative example using the phosphor without modification.

Example 7 In Example 1, (Y, Gd) (P, V) O ₄ modified with Al ₂ O ₃ as a red phosphor:
Eu and Zn whose surface is modified with Al ₂ O ₃ as a green phosphor
₂ SiO ₄ : Mn, and BaMgAl ₁₀ O ₁₇ : Eu surface-modified with Al ₂ O ₃ as a blue phosphor. A panel was manufactured in the same manner as in Example 1 except that the phosphor material and the modification material used were different.

After the panel was turned on for 30,000 hours, the maintenance ratio of the light emission luminance was measured. As a result, the luminance maintenance ratio when the phosphor material modified with Al ₂ O ₃ was used was increased by 15% as compared with the comparative example using the phosphor without modification. When the weight ratio of Al ₂ O _{3 to be} modified was 0.5 to 5 wt%, the luminance maintenance ratio showed almost the same value.

Example 8 In Example 7, (Y, Gd) BO ₃ : Eu modified with Al ₂ O ₃ as a red phosphor.
Was used. A panel was produced in the same manner as in Example 7, except that the red phosphor used was different. After the panel was turned on for 30,000 hours, the maintenance ratio of the light emission luminance was measured. The brightness maintenance ratio was increased by 15% as compared with the comparative example using the phosphor without modification.

Example 9 In Example 7, Y ₂ O ₃ : Eu modified with Al ₂ O ₃ was used as a red phosphor. A panel was produced in the same manner as in Example 7, except that the red phosphor used was different. After the panel was turned on for 30,000 hours, the maintenance ratio of the light emission luminance was measured. The brightness maintenance ratio was increased by 15% as compared with the comparative example using the phosphor without modification.

Example 10 In Example 7, BaAl ₁₂ O ₁₉ : Mn modified with Al ₂ O ₃ was used as a green phosphor. A panel was produced in the same manner as in Example 7, except that the green phosphor used was different. After the panel was turned on for 30,000 hours, the maintenance ratio of the light emission luminance was measured. The brightness maintenance ratio was increased by 15% as compared with the comparative example using the phosphor without modification.

Example 11 In Example 8, BaAl ₁₂ O ₁₉ : Mn modified with Al ₂ O ₃ was used as the green phosphor. A panel was produced in the same manner as in Example 8, except that the green phosphor used was different. After the panel was turned on for 30,000 hours, the maintenance ratio of the emission luminance was measured. The brightness maintenance rate is
15% compared to the comparative example using the phosphor without modification
Increased.

<Example 12> In Example 9, BaAl ₁₂ O ₁₉ : Mn modified with Al ₂ O ₃ was used as a green phosphor. A panel was produced in the same manner as in Example 9 except that the green phosphor used was different. After the panel was turned on for 30,000 hours, the maintenance ratio of the light emission luminance was measured. The brightness maintenance ratio was increased by 15% as compared with the comparative example using the phosphor without modification.

Example 13 In Example 1, (Y, Gd) (P, V) O ₄ : Eu, the surface of which was modified with diamond fine particles having an average particle diameter of 0.3 μm, as a red phosphor, and a green phosphor. Z is also surface-modified with diamond fine particles
n ₂ SiO ₄ : Mn was used, and as the blue phosphor, BaMgAl ₁₀ O ₁₇ : Eu similarly surface-modified with diamond fine particles was used. A panel was produced in the same manner as in Example 1, except that the phosphor and the modifying material used were different.

The maintenance ratio of the luminance after the panel was lit for 30,000 hours was measured. As a result, the luminance maintenance ratio in the case of the present example using the phosphor material modified with the diamond fine particles was 1 compared with the comparative example using the phosphor without modification.
Increased by 0%. The weight ratio of the diamond to be modified is 0.5-5
At wt%, the luminance maintenance ratio showed almost the same value.

Example 14 In Example 13, the red phosphor was modified with fine diamond particles (Y, Gd).
BO ₃ : Eu was used. A panel was produced in the same manner as in Example 13 except that the red phosphor used was different. After the panel was turned on for 30,000 hours, the maintenance ratio of the light emission luminance was measured. The luminance maintenance ratio increased by 10% as compared with the comparative example using the phosphor without modification.

Example 15 In Example 13, Y ₂ O ₃ : E modified with diamond fine particles as the red phosphor was used.
u was used. Example 13 except that a different red phosphor was used.
A panel was produced in the same manner as in the above. After the panel was turned on for 30,000 hours, the maintenance ratio of the light emission luminance was measured. The brightness maintenance ratio was 1 compared to the comparative example using the phosphor without modification.
Increased by 0%.

Example 16 In Example 13, BaAl ₁₂ modified with diamond fine particles was used as the green phosphor.
O ₁₉ : Mn was used. A panel was produced in the same manner as in Example 13 except that a different green phosphor was used. 3 panels
The light emission luminance maintenance rate after lighting for 10,000 hours was measured. The luminance maintenance ratio increased by 10% as compared with the comparative example using the phosphor without modification.

Example 17 In Example 14, BaAl ₁₂ modified with diamond fine particles was used as the green phosphor.
O ₁₉ : Mn was used. A panel was produced in the same manner as in Example 14 except that the green phosphor used was different. 3 panels
The light emission luminance maintenance rate after lighting for 10,000 hours was measured. The luminance maintenance ratio increased by 10% as compared with the comparative example using the phosphor without modification.

Example 18 In Example 15, BaAl ₁₂ modified with diamond fine particles was used as the green phosphor.
O ₁₉ : Mn was used. A panel was produced in the same manner as in Example 15 except that a different green phosphor was used. After the panel was turned on for 30,000 hours, the maintenance ratio of the light emission luminance was measured. The luminance maintenance ratio increased by 10% as compared with the comparative example using the phosphor without modification.

In the above embodiment, oxides of Al and Zn and fine diamond particles were described as typical examples of the luminance improving and modifying material, but other materials such as In, Ga, G
The same effects as those of the above embodiment can be obtained for metal oxide fine particles containing at least one of e and Bi.

[0047]

As described above, the desired object can be achieved by the present invention as described in detail. That is, it has become possible to realize a plasma display panel with high luminance and long life and an image display device using the same.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing an enlarged main part of a rear substrate for explaining an outline of the present invention.

FIG. 2 is an exploded view schematically illustrating the structure of the plasma display panel.

FIG. 3 is an enlarged view schematically showing a phosphor modified by a luminance improvement modifying material.

FIG. 4 is an enlarged sectional view of a main part of a rear substrate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Front substrate (glass plate), 2 ... Display electrode, 3 ... Dielectric layer, 4 ... Protective film (MgO), 5 ... Back substrate (glass plate), 6 ... Address electrode, 7 ... Discharge space, 8 ... Partition wall 9R: Red phosphor layer, 9G: Green phosphor layer, 9B: Blue phosphor layer, 9: Phosphor, 10: Luminance improvement modifying material.

Continued on the front page (72) Inventor Teruki Suzuki 1-280 Higashi Koikekubo, Kokubunji-shi, Tokyo Inside the Central Research Laboratory, Hitachi, Ltd. (72) Inventor Masatoshi Shiiki 1-280 Higashi Koigakubo, Kokubunji-shi, Tokyo Inside the Central Research Laboratory, Hitachi, Ltd. (72) Inventor Tadashi Furukawa 4-6, Kanda Surugadai, Chiyoda-ku, Tokyo Information Media Business Unit, Hitachi, Ltd. (72) Inventor Masaharu Ishigaki 4-6-Kanda Surugadai, Chiyoda-ku, Tokyo Information Media Business, Hitachi, Ltd. Within headquarters (72) Inventor Teruo Kurai 4-1-1, Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa F-term within Fujitsu Limited 5C040 FA01 GB02 GG08 MA03 MA30 5C058 AA11 BA05 5C094 AA10 AA37 BA12 BA31 BA32 CA19 CA24 DA13 EA04 EB03 EC04 FB02 FB03 JA01

Claims (11)

[Claims] 1. An Al, Zn, In, Ga, Ge and Bi alloy.
At least one selected from metal oxide fine particles containing at least one of the following, and at least one selected from diamond fine particles is attached to the surface of the phosphor particles as a brightness improvement modifying material, or mixed with the phosphor particles in a matrix of a phosphor layer. A plasma display panel comprising a phosphor layer of the plasma display panel. 2. A front substrate having a plurality of display electrodes, a plurality of address electrodes, a partition wall between the address electrodes, and a partition wall surface facing each other is a side wall, and at least the address electrode surface is a bottom surface. And a back substrate having a phosphor layer formed on the wall surface of the groove, and a discharge gas is sealed in a space in the groove formed by combining and sealingly fixing the front substrate and the back substrate. In the plasma display panel, Al, Zn,
At least one selected from metal oxide fine particles containing at least one of In, Ga, Ge, and Bi, and diamond fine particles is adhered to the surface of the phosphor particles constituting the phosphor layer as a brightness improvement modifying material, Alternatively, a plasma display panel characterized by being mixed with phosphor particles in a matrix of the phosphor layer. 3. The method of claim 1, wherein the material for improving brightness is Al ₂ O ₃ , Zn.
3. The plasma display panel according to claim 1, wherein the plasma display panel is made of at least one of O and diamond fine particles. 4. The phosphor material according to claim 1, wherein said phosphor layer contains 0.1% to 5.0% by weight of said phosphor material. Plasma display panel. 5. The average particle diameter of the luminance improving and modifying material constituting the phosphor layer is 1/10 of the average particle diameter of the phosphor.
The plasma display panel according to claim 1, wherein: 6. The plasma display panel according to claim 1, wherein the phosphor is a manganese-activated zinc silicate phosphor. 7. The plasma display panel according to claim 1, wherein the phosphor is a manganese-activated barium aluminate phosphor. 8. The plasma display panel according to claim 1, wherein the phosphor is a europium-activated rare earth phosphor-vanadate phosphor. 9. The plasma display panel according to claim 1, wherein the phosphor is europium-activated yttrium or gadolinium borate phosphor. 10. The plasma display panel according to claim 1, wherein the phosphor is a europium-activated barium-magnesium aluminate phosphor. 11. An image display device comprising the plasma display panel according to claim 1.