JP2003297253A - Plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate noise in a reduced pressure zone of a high height area by strengthening adhesion force of a front face of a glass substrate and a back face of the glass substrate of a main part of a panel. <P>SOLUTION: In the plasma display panel in which a pair of the substrates 1 and 8 are arranged in opposition so that space may be formed in between the substrates, and of which the peripheral part is sealed by a sealing component 15, by making the height of the sealing component 15 higher than the height of the barrier ribs 11, the panel with high adhesion force is produced also in the area of high altitude. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a large screen, thin type,
The present invention relates to a plasma display panel known as a lightweight display device.

[0002]

2. Description of the Related Art In recent years, plasma display panels have been
It is attracting attention as a display panel (thin display device) having excellent visibility, and high definition and large screen are being promoted.

The plasma display panel is roughly classified into an AC type and a DC type in terms of driving, and there are two types of discharge types, a surface discharge type and a counter discharge type.
At present, AC type and surface discharge type plasma display panels have become the mainstream due to the increase in screen size and the ease of manufacturing.

FIG. 6 shows an example of the structure of such a plasma display panel, FIG. 7 shows a cross section taken along line AA of FIG. 6, and FIG. 8 shows a cross section taken along line BB of FIG. Is shown. As shown in FIG. 6, a plurality of stripe-shaped display electrodes 4 forming pairs of scan electrodes 2 and sustain electrodes 3 are formed on a transparent front substrate 1 such as a glass substrate. A light-shielding layer 5 is formed between adjacent display electrodes 4. The scan electrodes 2 and the sustain electrodes 3 are transparent electrodes 2a and 3a and bus electrodes 2 made of silver or the like electrically connected to the transparent electrodes 2a and 3a, respectively.
b and 3b. In addition, a dielectric layer 6 is formed on the front substrate 1 so as to cover the plurality of pairs of electrodes.
And a protective film 7 is formed on the dielectric layer 6. In addition, a plurality of stripes covered with the underlying dielectric layer 9 are provided on the rear substrate 8 facing the front substrate 1 in the direction orthogonal to the display electrodes 4 of the scan electrodes 2 and the sustain electrodes 3. The data electrodes 10 are formed. A plurality of stripe-shaped partition walls 11 are arranged in parallel with the data electrodes 10 on the underlying dielectric layer 9 between the respective data electrodes 10, and the side surfaces 11 a between the partition walls 11 and the surface of the underlying dielectric layer 9 are arranged. A phosphor layer 12 is provided.

The substrate 1 and the substrate 8 are the scanning electrodes 2
Further, the sustain electrodes 3 and the data electrodes 10 are arranged so as to be orthogonal to each other with a minute discharge space interposed therebetween, and
The periphery is sealed, and the discharge space contains helium,
One of neon, argon, and xenon or a mixed gas is sealed as a discharge gas. Further, the discharge space is divided into a plurality of partitions by the partition wall 11,
A plurality of discharge cells 13 at which the intersections of the display electrodes 4 and the data electrodes 10 are located are provided. In each of the discharge cells 13, phosphor layers 12 are sequentially arranged one by one so as to be red, green and blue. There is.

As shown in FIG. 9, the electrode array of this panel has a matrix configuration of M rows × N columns of discharge cells, and M rows of scan electrodes SCN1 to SCNM and sustain electrodes SUS1 to SUSM in the row direction. Are arrayed and N in the column direction
The data electrodes D1 to DN of the column are arranged.

[0007]

In a panel body of a plasma display panel, a glass substrate on the front side and a glass substrate on the back side are bonded together with a partition wall sandwiched therebetween, and a discharge gas mainly composed of neon is provided inside. It is sealed at about 500 Torr, and normally the front glass substrate is pressed against the partition wall of the rear glass substrate by atmospheric pressure.

However, in a region where the atmospheric pressure of the outside air is low, particularly in a place where the altitude is high, the adhesion force between the front glass substrate and the rear glass substrate becomes weak, and the partition wall formed on the rear glass substrate and the front glass substrate are separated. There is a problem that a gap is generated and noise is generated during panel operation. This noise is perceived by the human sense of noise, and becomes annoying when the sound pressure exceeds 30 dB.

The present invention solves such a problem, and an object thereof is to eliminate noise in a depressurized area where the panel main body has a high altitude.

[0010]

To achieve the above object, in a plasma display panel of the present invention, a pair of substrates are opposed to each other so that a space is formed therebetween, and a peripheral portion is sealed by a sealing member. In addition, a partition wall for partitioning the space into a plurality of spaces is arranged, and a discharge gas is enclosed in the space partitioned by the partition wall to arrange electrodes on the substrate so that a discharge is generated, thereby forming a discharge cell, and a sealing member. The height of the partition wall is made higher than the height of the partition wall, and the adhesion between the partition wall and the front surface glass, which is configured on the back glass, can be maintained even in the highland where the atmospheric pressure is low, and the noise can be suppressed. can do.

In the plasma display panel according to a second aspect of the present invention, in the above structure, the sealing member is a mixture of materials having different melting points.

Further, the plasma display panel according to a third aspect of the present invention is characterized in that, in the above structure, the pressure for filling the discharge gas is smaller than the outside atmospheric pressure, whereby the noise generation height is further improved. Be peeled off.

An image display device according to a fourth aspect of the present invention is a plasma display panel having the above structure, a chassis for holding the plasma display panel, a chassis mounted on the chassis and for driving the plasma display panel to display. It features a drive circuit, and you can enjoy images comfortably with less noise.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION A plasma display panel according to an embodiment of the present invention will be described below with reference to the drawings.

The plasma display panel according to the present invention is different from the conventional plasma display panel only in the structure of the sealing portion, and the other components are the same.

First, the plasma display panel will be specifically described with reference to FIGS.

The front panel is made of ITO on the substrate 1 on the front side.
Alternatively, the transparent electrodes 2a and 3a made of a transparent conductive material such as tin oxide (SnO ₂ ) and a thick film of silver (Ag) (thickness:
2 μm to 10 μm), aluminum (Al) thin film (thickness: 0.1 μm to 1 μm) or Cr / Cu / Cr laminated thin film (thickness: 0.1 μm to 1 μm), and the bus electrodes 2b and 3b are sequentially laminated. Low melting point glass having a thickness of 20 μm to 50 μm and containing lead oxide (PbO), bismuth oxide (Bi ₂ O ₃ ) or phosphorus oxide (PO ₄ ) as a main component (for example, 70% by weight of lead oxide (PbO) and boron oxide (PbO)). 15% by weight of B ₂ O ₃ ) and 15% by weight of silicon oxide (SiO ₂ )) is used to form the dielectric layer 6 by screen printing, die coating printing, film laminating method or the like. As an example, the bus electrodes 2b and 3b
In the case where is composed of a silver electrode, the silver electrode ink containing an ultraviolet photosensitive resin is uniformly applied by a screen printing method, dried, and then formed by patterning and baking by exposure and development.

Next, in order to protect the dielectric layer 6 from damage due to plasma, a thickness of 100 nm to 10 nm made of MgO is used.
The front panel is manufactured by forming the protective layer 7 of 00 nm by the electron beam evaporation method or the sputtering method.

On the other hand, on the rear panel side, first, the rear substrate 8
A silver (Ag) thick film having a thickness of 2 μm to 10 μm and a thickness of 0.
A data electrode 10 made of an aluminum (Al) thin film having a thickness of 1 μm to 1 μm or a Cr / Cu / Cr laminated thin film having a thickness of 0.1 μm to 1 μm, lead oxide (PbO), bismuth oxide (Bi ₂ O ₃ ) or phosphorus oxide (PO _4). A base dielectric layer 9 made of a low melting point glass having a thickness of 5 μm to 20 μm and containing (4) as a main component is formed. Further, partition walls 11 containing glass as a main component are formed at a predetermined pitch, and a red phosphor (R), a green phosphor (G), in each space sandwiched by the partition walls 11,
A phosphor layer 12 made of a blue phosphor (B) was formed, and a back panel side was prepared.

Here, the underlying dielectric layer 9 is for improving the adhesion with the partition wall 11, and the plasma display panel does not operate without it. The phosphor layers 12 are formed by mixing the powders of the red phosphor (R), the green phosphor (G), and the blue phosphor (B) with a vehicle, and applying paste to the phosphor layers 12 by an ink discharge method. . As the phosphor of each color, phosphor materials generally used in plasma display panels are shown below.

Red phosphor (R): (Y_XGd_1-X) B
O₃: Eu³⁺  Or YBO₃: Eu ³⁺ Green phosphor (G): BaAl₁₂O₁₉: Mn or
Zn₂SiO_Four: Mn Blue phosphor (B): BaMgAl_TenO₁₇: Eu²⁺ In addition, each color phosphor powder is manufactured as follows.
It

First, the blue phosphor is made of barium carbonate (BaCO ₃ ), magnesium carbonate (MgCO ₃ ), and
Aluminum oxide (α-Al ₂ O ₃ ) is mixed in a molar ratio of 1: 1/5. Next, a predetermined amount of europium oxide (Eu ₂ O ₃ ) is added to this mixture. Then, it is mixed in a ball mill with an appropriate amount of flux (AlF ₂ , BaCl ₂ ) and baked at 1000 ° C. to 1200 ° C. for a predetermined time (for example, 5 hours) in a weak reducing atmosphere (in H ₂ , N ₂ ). It is obtained by sieving.

The red phosphor contains, as raw materials, yttrium oxide (Y ₂ O ₃ ) and boric acid (H ₃ BO ₃ ) in a molar ratio of 1: 2. Next, a predetermined amount of europium oxide (Eu ₂ O ₃ ) was added to this mixture, and the mixture was mixed with an appropriate amount of flux in a ball mill, and the mixture was heated in air at 950 ° C to 1200 ° C.
It is obtained by calcination after calcination for a predetermined time (for example, 5 hours).

The green phosphor is made of zinc oxide (Zn oxide) as a raw material.
O), silicon oxide (SiO₂) In a molar ratio of 2: 1
It Next, a predetermined amount of manganese oxide is added to this mixture.
(Mn ₂O₃) Is added and mixed in a ball mill, then air
Medium temperature 950 ° C to 1200 ° C for a predetermined time (for example, 5 hours)
It is obtained by firing and sieving.

The front panel and the rear panel produced as described above are attached to each other by using a sealing member 15 containing glass as a main component as shown in FIG. The sealing member 15 is a mixture of a low melting point glass material 15b, for example, a glass material having a transition point of 300 to 340 ° C. and a high melting point glass material 15a, for example, a glass material having a transition point of 470 to 550 ° C. . The average particle size of the high melting point glass material 15a is preferably 110 to 180 μm, which is 1.02 to 1.125 times the height p of the partition wall 11. Further, with respect to the shape of the high melting point glass material 15a, it is desirable that it is substantially spherical or columnar, the diameter thereof is 110 to 140 μm, and the height of the column is 110 to 180 μm.
Further, the mixing amount of the high melting point glass material 15a is 0.05 to 20.
Mass% (volume ratio is almost the same) is desirable. 0.05
When the content is less than mass%, the thermal expansion of the low-melting glass material 15b is too large, so that the expansion of the sealing member is large and the temperature is high (450 ° C).
When it is sealed with, it will flow sideways, and it will not be possible to achieve the desired height. Higher melting point glass material 15 at 20 mass% or more
Since a is aggregated, the height of the sealing member varies. From this, the mixing amount of the high melting point glass material 15a is 0.0
5 to 20 mass% is desirable.

However, it is also effective for shapes other than the above, such as cubes, polyhedra, prisms, pyramids, and irregular shapes. In that case, there is a risk of aggregation, so an average particle size of 110 to 160 μm is required. Preferably, the mixing amount is 0.01 to
15 mass% is preferable.

Next, the procedure for sealing will be described. A paste-like sealing member obtained by mixing the low melting point glass material 15b and the high melting point glass material 15a described above is applied to the peripheral portion of at least one glass substrate with a width of 0.5 mm.

Next, the front panel and the rear panel thus produced are bonded together by using the sealing member 15 described above, and the inside of the discharge space 13 partitioned by the partition wall 11 is subjected to high vacuum (1 × 10 5). After exhausting to ^-4 Pa), a discharge gas having a predetermined composition is sealed at a predetermined pressure to produce a plasma display panel. As an example, a mixed gas of neon gas and xenon gas in volume%,
95% and 5%, and the pressure is 66.5 kPa (500To
rr).

As shown in FIG. 2, the plasma display panel 31 of the present invention manufactured in this manner is decompressed as shown in FIG.
It is arranged in 2 and the drive voltage waveform is input to the display electrode 4 to light it, the pressure in the tank 32 is reduced by the vacuum pump 33, the pressure in the tank 32 is monitored by the pressure gauge 34, and generated from the panel 31. The noise to be collected was collected by the microphone 35, and the sound pressure was measured by the noise measuring device 36. Noise generation altitude is tank 3
It was calculated from the correlation between the pressure in 2 and the altitude. as a result,
The panel of the present invention had an altitude of 3000 m above 30 dB.

The reason why the noise generation level of the panel of the present invention was high is that the panel thickness of the peripheral portion is thicker than that of the central portion of the panel, and the front panel has a shape that does not easily bulge outward. Conceivable.

On the other hand, a comparative panel having the same other constituent elements as the above panel was prepared by using the high melting point glass material 15a having an average particle diameter substantially equal to that of the partition wall. When the shape of this comparative panel was measured, it had a substantially uniform thickness on the front surface as shown in FIG. 3, and when the noise generating height of this comparative panel was measured in the same manner as the panel of the present invention, it was 20
It exceeded 30 dB at 00 m.

Next, as shown in FIG. 4, the dielectric layer 6 formed on the front substrate 1 and the rear substrate 8 are related to each other in terms of the adhesion between the front panel and the rear panel when they are sealed. For the plasma display panel in which the formed base dielectric layer 9 is cut before the sealing layer, the dielectric layer 6 (height) that covers the substrate 1 when sealing the front panel and the rear panel d
1), the partition wall 11 (height p), and the space (D = D) determined by the underlying dielectric layer 9 (d2) printed on the substrate 8.
A panel was produced using the high melting point glass material 15a which is 1.05 to 1.1 times higher than d1 + p + d2).

When the noise generation altitude was examined in the same manner as in the panel of the present invention, the altitude above 30 dB was 3000 m. The reason why the altitude of noise generation is high is
It is considered that, like the panel according to the present invention, the peripheral portion of the panel is thicker than the central portion.

In the present invention, instead of using the high melting point glass material 15a for the sealing member 15, the refractory filler material is used to form the panel. Specifically, as the refractory filler, a heat-resistant inorganic filler such as silica, alumina, or cordierite is used, and the average particle size of the refractory filler is changed to 100 to 160 μm. Was set to 0.05 to 15% by mass (almost equal in volume ratio). Where the refractory filler is 15
If it is more than mass%, the powder will agglomerate and cannot be uniformly dispersed. On the other hand, if the content is 0.05% by mass or less, the height of the sealing layer varies after sealing, and the height cannot be regulated. Particularly preferred is 1 to 10% by mass. Further, the preferred shape of the refractory filler is
It is roughly spherical or cylindrical. Similar effects can be obtained with other shapes, such as irregular shapes.

Similar to the above-described embodiment, such a plasma display panel can suppress the bulge of the panel even in a high altitude area by sealing the peripheral portion of the panel so as to bend outward. It is possible to suppress the noise generated from the peripheral portion of the panel.

Further, in the plasma display panel of the present invention, the pressure to be filled is 66.7 kPa (500 T).
53.4 kPa (400 Torr) lower than
By increasing the internal / external pressure difference by setting the pressure to 63.2 kPa (475 Torr), it is possible to enhance the adhesion between the front panel and the rear panel even when the shape of the peripheral portion of the panel varies. The bulge can be suppressed and the noise can be further suppressed.

In this panel, 53.4k
If it is less than Pa, the brightness is lowered and the life time of the plasma display panel is greatly reduced. Also, 63.2
Above kPa, the pressure difference between the inside and the outside is almost the same as the conventional 66.7 kPa, and it is not possible to give superiority. Therefore, the pressure to be filled is 53.4 kPa (400 To
rr) to 63.2 kPa (475 Torr) is desirable. Also, reducing the pressure inside the panel body causes a decrease in brightness, so the proportion of xenon should be 5-10%.
And the composition ratio that matches each internal pressure was selected. As an example, 6
When the pressure is 3.2 kPa, the mixing ratio of neon and xenon is 94.
It was set to 6%.

Next, an image display device using the plasma display panel of the present invention will be described with reference to FIG. FIG. 5 shows an example of the overall configuration of an image display device incorporating the plasma display panel described above. In the figure, a housing for accommodating the panel body 21 includes a front frame 22 and a metal back cover 23,
A front cover 24 made of glass or the like, which also serves as an optical filter and protects the panel body 21, is provided in the opening of the front frame 22.
Are arranged. Further, for example, silver vapor deposition is applied to the front cover 24 in order to suppress unnecessary radiation of electromagnetic waves. Further, the back cover 23 has a panel body 2
A plurality of vent holes 23a are provided for radiating the heat generated in 1 and the like to the outside.

The panel body 21 is held by being adhered to the front surface of a chassis 25 made of aluminum or the like via a heat conduction sheet 26, and the rear surface side of the chassis 25 is used to drive the panel body 21 for displaying. A plurality of drive circuit blocks 27 are attached. The heat conductive sheet 26 is for efficiently transmitting the heat generated in the panel body 21 to the chassis 25 and radiating the heat. The drive circuit block 27 includes an electric circuit for driving and controlling the display of the panel body 21,
A plurality of flexible wiring boards (not shown) that extend beyond the four edge portions of the chassis 25 are electrically connected to the electrode lead portions that are led to the edge portions of the panel body 21.

Further, on the rear surface of the chassis 25, a boss portion 25a for mounting the drive circuit block 27 and fixing the back cover 23 is provided by projecting integrally by die casting or the like. The chassis 25 may be constructed by fixing a fixing pin to an aluminum flat plate.

Such an image display device does not generate noise even in actual operation in high altitude where the atmospheric pressure is low.

[0042]

As is apparent from the above description, according to the present invention, it is possible to provide a plasma display panel and an image display device capable of suppressing noise in actual operation in a high altitude where the atmospheric pressure is low. .

[Brief description of drawings]

FIG. 1 is a sectional view showing a plasma display panel according to an embodiment of the present invention.

[Fig. 2] Schematic diagram of depressurization tank test

FIG. 3 is a sectional view showing a conventional plasma display panel.

FIG. 4 is a sectional view showing a plasma display panel according to another embodiment of the present invention.

FIG. 5 is an exploded perspective view showing the internal arrangement structure of the image display device of the present invention.

FIG. 6 is a perspective view showing a plasma display panel.

7 is a sectional view taken along line AA of FIG.

FIG. 8 is a sectional view taken along line BB in FIG.

FIG. 9 is an explanatory diagram showing an electrode array of the plasma display panel.

[Explanation of symbols]

1,8 substrate 2 scanning electrodes 3 sustain electrodes 4 display electrodes 6 Dielectric layer 7 protective layer 9 Base dielectric layer 10 data electrodes 11 partitions 12 Phosphor layer 13 discharge cells 15 Sealing member 21 panel body 25 chassis 27 Drive circuit block

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Koji Aoto             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F term (reference) 5C040 FA01 FA04 GB03 GF02 GJ08                       HA01 HA02 KA09 KA10 KB03                       KB11 LA14 MA30

Claims (4)

[Claims] 1. A pair of substrates are arranged so as to face each other so that a space is formed therebetween, a peripheral portion is sealed by a sealing member, and a partition wall for partitioning the space into a plurality is arranged. In a plasma display panel having discharge cells filled with discharge gas in the space partitioned by the electrodes so that discharge is generated, the height of the sealing member is higher than the height of the barrier ribs. A plasma display panel characterized by the above. 2. The plasma display panel according to claim 1, wherein the sealing member is a mixture of materials having different melting points. 3. The plasma display panel according to claim 1, wherein the pressure for filling the discharge gas is smaller than the atmospheric pressure. 4. The plasma display panel according to claim 1, a chassis for holding the plasma display panel, and a drive attached to the chassis for driving the display of the plasma display panel. An image display device including a circuit.