JP3563994B2 - Front panel unit for plasma display panel and plasma display panel using the same - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a front panel unit for a plasma display panel and a plasma display panel using the same.
[0002]
[Prior art]
In a plasma display panel (PDP), which is a gas discharge panel, a pair of electrodes arranged regularly on two opposing glass substrates are provided, and a rare gas mainly containing Ne, He, Xe, or the like is sealed between them. It has a structure. Then, a voltage is applied between these electrodes, and a discharge is generated in minute cells around the electrodes, so that each cell emits light and display is performed. In order to display information, cells arranged regularly are selectively discharged and emitted. There are two types of PDPs, a direct current type (DC type) in which the electrodes are exposed to the discharge space and an alternating current type (AC type) in which the electrodes are covered with an insulating layer. And a refresh driving method and a memory driving method.
[0003]
As described above, the plasma display panel adopts a form in which two glass substrates are opposed to each other. More specifically, (1) a transparent substrate, electrodes formed on the substrate, dielectric layers, And (2) a back panel unit for a plasma display panel having a phosphor layer, wherein the units (1) and (2) are sealed cells. Are fixed at regular intervals.
[0004]
The MgO protective layer formed on the front plate unit is mainly used to prevent ion bombardment due to discharge (spatter resistance), and to increase the secondary electron emission ratio and lower the discharge voltage. The protective layer is generally formed by a vacuum process such as an EB evaporation method.
[0005]
However, since MgO has deliquescence, for example, when the front plate unit is stored in the atmosphere after forming a MgO protective layer, a reaction represented by the following formula on the MgO surface, that is, MgO is H ₂ React with O and CO ₂ respectively to produce MgCO ₃ .Mg (OH) ₂ .
[0006]
4MgO + 3CO ₂ + 4H ₂ O → 3MgCO ₃ .Mg (OH) ₂ .3H ₂ O
[0007]
The MgO surface deliquescent due to such a reaction becomes cloudy, and the cloudy portion has become brittle enough to be easily scraped off. Therefore, such a change in the MgO surface deteriorates the performance of the PDP panel, such as the service life and discharge voltage, and poses a problem from the viewpoints of reliability, durability and the like.
[0008]
In order to cope with such a problem, conventionally, (1) immediately after completing the front plate unit by forming a film of MgO, bonding this to a back plate unit in a vacuum, and sealing it, Alternatively, a method has been adopted in which (2) a completed front plate unit formed by depositing MgO is stored in a vacuum.
[0009]
[Problems to be solved by the invention]
However, with the measures (1) and (2), a satisfactory response cannot be taken when the panel size becomes large.
[0010]
Under such circumstances, the present invention has been devised. The object of the present invention is to prevent the deliquescence reaction of MgO and to make it extremely easy to preserve, as well as to make the panel size relatively easy. It is an object of the present invention to provide a front panel unit for a plasma display panel that can respond and is excellent in workability, and to provide a plasma display panel using the same.
[0011]
[Means for Solving the Problems]
In order to solve such a problem, the present invention provides a front panel unit for a plasma display panel including a substrate, an electrode formed on the substrate, a dielectric layer, and an MgO protective layer.
A silicon oxide (SiOx) layer is formed on the MgO protective layer;
The silicon oxide (SiOx) layer is configured such that the X value of SiOx is in the range of 1.3 to 1.9 .
[0014]
In a preferred embodiment of the present invention, the silicon oxide (SiOx) layer has a thickness of 200 to 1000 °.
[0015]
In a preferred embodiment of the present invention, the silicon oxide (SiOx) layer is continuously formed in a vacuum after the formation of the MgO protective layer.
[0016]
Further, the plasma display panel of the present invention includes the plasma display panel front panel unit and a plasma display panel rear panel unit having a phosphor layer, and the pair of units constitute a sealed cell. It is fixed and configured.
[0017]
The plasma display panel is configured such that the silicon oxide (SiOx) layer component scattered due to the plasma discharge is present in the cell of the plasma display panel.
[0018]
Since the silicon oxide (SiOx) layer is formed on the MgO protective layer in the front panel unit for a plasma display panel according to the present invention, the barrier layer is excellent in oxygen / water vapor barrier properties and the MgO protective layer is hardly deteriorated. .
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, before describing the front panel unit 100 for a plasma display panel of the present invention, the configuration of the entire plasma display panel will be briefly described.
[0020]
FIG. 1 is a perspective view showing one configuration example of an AC type PDP. In this figure, a front panel unit 100 for a plasma display panel (hereinafter, simply referred to as "front panel unit 100") includes a front panel 1, a sustain electrode 4, a bus electrode 5, and a dielectric layer 6 formed thereon. , And an MgO layer 7, and the present invention further includes a silicon oxide (SiOx) layer 30 formed on the MgO layer 7. On the other hand, a back panel unit 200 for a plasma display panel (hereinafter, simply referred to as “back panel unit 200”) paired with the front panel unit 100 has a rear panel 2 and a predetermined gap above the rear panel 1. It has a plurality of standing partitions 3, address electrodes 8 provided between the partitions, and a phosphor layer 9 applied between the partitions 3 so as to cover the address electrodes 8.
[0021]
FIG. 1 shows a state in which the front panel 1 (front panel unit 100) and the rear panel 2 (back panel unit 200) are separated so that the configuration of the PDP can be easily understood. As shown in FIG. 1, an AC type PDP has a front plate 1 and a rear plate 2 which are transparent substrates such as a glass plate, which are opposed to each other in parallel, and a front plate 1 is formed by a partition wall 3 which is provided upright on the rear plate 2. And the back plate 2 are fixed at regular intervals so as to form a sealed cell.
[0022]
On the back plate 2 side (the lower side in the drawing) of the front plate 1, as described above, for example, a composite electrode composed of a sustain electrode 4 which is a transparent electrode and a bus electrode 5 which is a metal electrode is formed in parallel with each other. A dielectric layer 6, an MgO layer 7, and a silicon oxide (SiOx) layer 30 are sequentially formed so as to cover this. Such a stacked state is shown in detail in a partially enlarged sectional view of FIG.
[0023]
On the front side (upper side in the drawing) of the back plate 2, address electrodes 8 are formed in a stripe shape parallel to each other so as to be orthogonal to the composite electrode and located between the partition walls 3. The phosphor layer 9 is provided on the bottom surface of the cell.
[0024]
Such an AC type PDP is of a surface discharge type, in which a predetermined voltage is applied from an AC power source between composite electrodes on the front panel 1 to form an electric field, and the front panel 1, the rear panel 2 and the partition 3 are connected to each other. Discharge is performed in each cell as a divided display element.
[0025]
The phosphor 9 emits light by the ultraviolet rays generated by the discharge, so that the light transmitted through the front plate 1 can be visually recognized by the observer.
[0026]
For the partition wall 3 for PDP, a method of pattern-printing the coating composition for forming a partition wall into a partition shape by screen printing, or applying the coating composition for forming a partition wall by screen printing, blade coating, die coating, etc., and drying to form a solid film After that, a mask having sand blast resistance is formed in a pattern on the solid film, sand blasting is performed, and the mask is peeled off and then fired.
[0027]
The partition wall 3 formed after such sintering contains a glass frit serving as a molten matrix of the partition wall 3 and an aggregate for mainly maintaining the shape and strength of the partition wall.
[0028]
The first feature of the present invention resides in the structure of the front panel unit 100 as shown in FIGS. That is, the silicon oxide (SiOx) layer 30 is formed on the MgO protective layer 7 in the front panel unit 100 of the present invention.
[0029]
The X value of SiOx in such a silicon oxide (SiOx) layer 30 is set in the range of 1.0 to 2.0, preferably in the range of 1.3 to 1.9. When this value is less than 1.0, the transparency becomes poor or the insulating property becomes poor, and the characteristic tendency unfavorable as a plasma display panel occurs. Also, when this value is increased, there is a tendency that the water vapor and oxygen barrier properties are deteriorated, and there is a problem that the protection of the MgO surface becomes insufficient. Note that the X value is defined as an average value from the film surface to a depth of 10 to 100 ° as measured by ESCA.
[0030]
The thickness of the silicon oxide (SiOx) layer 30 is set to 200 to 1000 °, preferably 200 to 500 °. If this value is less than 200 °, there arises a disadvantage that a sufficient barrier function cannot be exhibited. If this value exceeds 1000 °, an excessive film thickness results, which is not economically preferable. A large amount of scattered components of the aged silicon oxide may be present in the cell, which may adversely affect the characteristics.
[0031]
It is preferable that such a silicon oxide (SiOx) layer 30 is continuously formed in vacuum in the same true film forming tank after the MgO protective layer 7 is formed in vacuum. This is for efficiently preventing the deliquescence reaction and contamination on the surface of the MgO protective layer 7. As the vacuum film forming method, for example, sputtering, EB vapor deposition and the like can be mentioned.
[0032]
By covering the surface of the MgO protective layer 7 with the silicon oxide (SiOx) layer 30 in this way, the surface of the MgO can be shifted to the next sealing step without being exposed to the air.
[0033]
In the sealing step, as shown in FIG. 1, the front plate unit 100 described above and the back plate unit 200 having the phosphor layer 9 are sealed to form a sealed cell. In this sealing step, the form of the plasma display panel is completed.
[0034]
The plasma display panel formed through the sealing step in this manner can be used as a product as it is. However, in general, an aging step is provided after the sealing, and the silicon oxide (SiOx) layer 30 Is desirably removed by sputtering (which is necessarily sputtered when light is emitted in the cell). This is for exposing the MgO to enhance the discharge performance. This aging step is performed by using a sealing gas such as Ne or Xe sealed in the cell, for example, at a pressure of 300 mTorr, a discharge voltage of 210 V, and an aging time of 10 hours. The silicon oxide layer 30 is relatively easily removed by sputtering (aging) as compared with MgO. By this aging treatment, it has been confirmed that the silicon oxide (SiOx) layer component scattered due to the plasma discharge is present in the cell.
[0035]
Further, even if the product is shipped without an aging step, the silicon oxide (SiOx) layer 30 tends to be removed with the passage of the actual use time, and the inside of the cell is caused by plasma discharge. The scattered silicon oxide (SiOx) layer components are present.
[0036]
【Example】
Hereinafter, the present invention will be described in more detail by way of specific examples.
[Experimental example I]
[0037]
(Example 1)
[0038]
An MgO protective layer was formed on a Corning 1737 glass substrate to a thickness of 5000 ° by EB evaporation. The film forming conditions for the MgO protective layer were as follows: operating pressure (degree of vacuum for film formation) 5 × 10 ⁻⁵ Torr, acceleration voltage 6.1 kV, and substrate temperature 100 ° C.
[0039]
Next, on the MgO protective layer thus formed, a silicon oxide (SiOx) layer having a thickness of 500 ° was continuously formed by a reactive sputtering method using the same film forming apparatus. A sample was prepared. The conditions for forming the SiOx layer include an operating pressure (degree of vacuum of film formation) of 3.8 × 10 ⁻⁴ Torr, an introduced argon (Ar) gas flow rate of 17 sccM, an introduced oxygen (O ₂ ) gas flow rate of 5 sccM, and a discharge pressure of 0.2 kW. And
[0040]
When the X value of SiOx was measured by ESCA (ESCALAB Mk II, manufactured by VG SCIENTIFIC), X was 1.9. The measurement conditions at this time were: X-ray source: Alkα, X-ray output: 15 kV · 20 mA, measurement area: 10 mmΦ, photoelectron escape angle: 90 °.
[0041]
(Examples 2 to 4)
[0042]
In the first embodiment, silicon oxide layers having different degrees of oxidation were provided by changing the flow rate of the introduced oxygen (O ₂ ) gas when forming the silicon oxide (SiOx) layer. Otherwise, in the same manner as in Example 1, a sample with X = 1.6 (sample of Example 2), X = 1.3 (sample of Example 3), and X = 1.1 (sample of Example 4) was used. Each was produced.
[0043]
(Examples 5 and 6)
[0044]
In Example 1, the thickness of the silicon oxide (SiOx) layer was changed to 200 ° (sample of Example 5) and 800 ° (sample of Example 6), respectively. Otherwise, in the same manner as in Example 1, samples of Example 5 and Example 6 were produced.
[0045]
(Comparative Example 1)
[0046]
In Example 1 described above, no silicon oxide (SiOx) layer was provided. Otherwise, a sample of Comparative Example 1 was produced in the same manner as in Example 1 above.
[0047]
The various samples (Examples 1 to 6 and Comparative Example 1) thus produced were subjected to an acceleration test in the following manner, and (1) appearance and (2) SEM surface observation were performed.
[0048]
The sample was left for 60 minutes in a constant temperature / humidity chamber (suga test indoor / outdoor temperature difference deterioration tester) at an acceleration test of 80 ° C. and 80% RH. Thereafter, the sample was taken out, a photograph of the appearance of the sample after the acceleration test was taken, and compared with a photograph of the appearance before the test, which was taken in advance. Further, the surface state of the sample before and after the test was compared and observed by SEM (S-4500, manufactured by Hitachi, Ltd .; measurement conditions: acceleration voltage 5 kV, emission current 10 μA).
Test Results (1) Appearance The entire surface of the MgO layer in the sample of Comparative Example 1 was clouded by the accelerated test. On the other hand, in all of the samples of Examples 1 to 6 having the SiOx layer on the MgO layer, the entire surface of the MgO layer was able to maintain a transparent state, and no change was observed before and after the acceleration test. .
(2) SEM surface observation The MgO layer in the sample of Comparative Example 1 was confirmed by an accelerated test to have a porous (sponge-like) structure on the surface. On the other hand, in each of the samples of Examples 1 to 6 having the SiOx layer on the MgO layer, almost no change was observed before and after the acceleration test.
【The invention's effect】
The effects of the present invention are clear from the above results. That is, the present invention provides a front panel unit for a plasma display panel including a transparent substrate, an electrode, a dielectric layer, and an MgO protective layer formed on the transparent substrate, wherein silicon oxide (SiOx) is formed on the MgO protective layer. ) Since the layer is formed and formed, the deliquescent reaction of MgO can be prevented, and a front panel unit for a plasma display panel having extremely excellent preservability can be provided, and handling and workability are good. Such an effect works extremely effectively even if the panel size is increased. Further, since the sputtering rate (atoms / ion) of SiOx is 4 times or more (Ar ions 600 eV) higher than that of MgO, the aging time conventionally performed tends to be shortened. In this case, aging of the MgO surface is unnecessary because there is no contamination).
[Brief description of the drawings]
FIG. 1 is a perspective view showing a configuration example of an AC type PDP.
FIG. 2 is a cross-sectional view for explaining the structure of the front panel unit of FIG. 1;
DESCRIPTION OF SYMBOLS 1 ... Front plate 2 ... Back plate 3 ... Partition wall 4 ... Sustain electrode 5 ... Bus electrode 6 ... Dielectric layer 7 ... MgO layer 8 ... Address electrode 30 ... Silicon oxide (SiOx) layer 100 ... Front plate unit 200 ... Back plate unit

Claims (5)

In a front plate unit for a plasma display panel including a substrate and an electrode formed on the substrate, a dielectric layer, and an MgO protective layer,
A silicon oxide (SiOx) layer is formed on the MgO protective layer;
The X value of SiOx in the silicon oxide (SiOx) layer is 1.3 to 1.9.
A front panel unit for a plasma display panel. The front panel unit for a plasma display panel according to claim 1, wherein the silicon oxide (SiOx) layer has a thickness of 200 to 1000 °. 3. The front panel unit for a plasma display panel according to claim 1, wherein the silicon oxide (SiOx) layer is formed by vacuum deposition continuously after the formation of the MgO protective layer. A front panel unit for a plasma display panel according to any one of claims 1 to 3, and a rear panel unit for a plasma display panel having a phosphor layer. A plasma display panel fixed so as to constitute a plasma display panel. The plasma display panel according to claim 4 , wherein the silicon oxide (SiOx) layer component scattered due to plasma discharge is present in the cell.

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