KR20100026772A - Plasma display panel - Google Patents

Abstract

PURPOSE: A plasma display panel using a protection film is provided to reduce a wrong discharge while reducing a jitter to a discharge delay. CONSTITUTION: A first substrate(170) has an address electrode, a first dielectric layer(190) and a barrier rip(140). The second substrate(110) is combined with the first substrate while the barrier is interposed between them. The second substrate has a sustain electrode pair, a second dielectric layer, and a protective film(195). The protective film comprises powder in which crystals have different re-crystallization.

Description

Plasma display panel

The present invention relates to a plasma display panel, and more particularly to a protective film of the plasma display panel.

BACKGROUND ART In general, a plasma display panel is a device for realizing a predetermined image by exciting phosphors by ultraviolet rays generated by gas discharge. The plasma display panel is configured as a large-screen display with high resolution and is drawing attention as a next-generation thin display device.

The plasma display panel may be classified into an AC type and an AC type.

The AC plasma display panel has a structure in which an electrode formed in a discharge space is not covered by a dielectric and is not exposed, and the DC plasma display panel has a structure in which an electrode formed in a discharge space is exposed.

An AC plasma display panel which is generally used at present is composed of a back substrate and a front substrate, and has discharge cells which are discharge spaces therebetween.

An address electrode is formed on the rear substrate, a dielectric layer is formed on the address electrode, and a partition wall for separating discharge cells is formed on the dielectric layer.

Subsequently, a phosphor layer is formed in the discharge cells divided by the partition walls.

Next, a sustain electrode pair composed of a pair of transparent electrodes and a bus electrode is formed on the front substrate in a direction crossing the address electrode, and a dielectric layer and a protective film are formed on the front substrate including the sustain electrode pair.

Then, the back substrate and the front substrate are joined by a sealing material, thereby completing the plasma display panel.

As described above, in the plasma display panel fabricated, the protective film for protecting the dielectric layer mainly uses MgO.

In general, the MgO passivation layer serves to maintain the discharge even at a voltage lower than the driving voltage due to wall charges formed on the surface during the discharge of the plasma display panel.

In addition, the MgO passivation layer serves to increase the discharge power efficiency by supplying secondary electrons to lower the discharge voltage of the plasma display panel, thereby causing plasma discharge even at a lower voltage. Thereby preventing the decomposition reaction from occurring.

However, such an MgO protective film has become a major cause of discharge delay phenomenon, that is, jitter phenomenon, which takes time until discharge occurs without discharge immediately after an electrical signal for generating discharge is input.

This is because the amount of secondary electrons emitted to the ions incident from the plasma is small due to the material properties of MgO.

That is, the MgO protective film causes surface deformation by physical and chemical adsorption of atmospheric water or carbon dioxide on the MgO surface, and acts as a factor that inhibits secondary electron emission on the surface of the protective film, resulting in deterioration of discharge characteristics. It acts as an element.

Therefore, due to such jitter, there has been a problem that the plasma display panel has to additionally configure the scan circuit unit so that the next signal can be input after waiting for a sufficient time for discharge to occur after inputting an electrical signal.

In addition, as the MgO protective film is used for a long time, jitter becomes more severe, and an afterglow erroneous discharge phenomenon in which the light emitting cells to emit light do not occur may cause black noise to appear in the display image.

In order to solve these problems, various methods for the development of new protective film materials and improvement of the protective film properties have been studied.

An object of the present invention is to solve these problems, by using a protective film mixed with materials having different recrystallization growth rate, to provide a plasma display panel that can reduce the jitter phenomenon to the discharge delay while at the same time reduce the afterglow mis-discharge. It is.

According to the present invention, a plasma display panel includes a first substrate having an address electrode, a first dielectric layer, and a partition wall, and a second substrate having a sustain electrode pair, a second dielectric layer, and a passivation layer coupled to the first substrate with a partition wall therebetween. The protective film may include a powder having at least two or more crystals having different recrystallization growth rates.

The protective film may include a mixed powder obtained by mixing a first powder having a crystal composed of a (100) plane and a second powder having a crystal including at least one (111) plane.

The second powder may be any one of a first crystal composed of a (111) plane, a second crystal composed of a (100) plane and a (111) plane, and a mixed crystal in which the first crystal and the second crystal are mixed. .

In addition, the content of the second powder having a crystal including at least one (111) plane may be 5 to 95% of the total mixed powder.

Next, the recrystallization growth rate of the second powder may be faster than the recrystallization growth rate of the first powder.

The protective film is then formed over a second dielectric layer and comprises a first layer comprising MgO, a first MgO powder formed on the first layer and having a crystal composed of (100) planes and at least one (111) plane. It may consist of a 2nd layer containing the mixed powder which mixed the 2nd MgO powder which has the crystal to make.

The protective film may be doped with at least one dopant selected from Al, B, Ba, Ca, Cr, Fe, Ge, Ga, In, Mn, Ni, P, Sc, Si, Y.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings.

The plasma display panel according to the present invention has the following effects.

According to the present invention, by forming a protective film by mixing materials having different recrystallization growth rates, it is possible to reduce the afterglow erroneous discharge while reducing jitter for discharge delay.

That is, according to the present invention, a protective film is formed by mixing a first powder having a crystal composed of a (100) plane and a second powder having a crystal including at least one (111) plane to form a protective film, thereby improving discharge delay. 1 It is possible to inhibit the recrystallization of the powder and to promote the recrystallization of the second powder having an effect of improving the afterglow misdischarge, thereby preventing the discharge delay phenomenon and the increase in the afterglow misdischarge caused by long time use.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a view illustrating a plasma display panel according to the present invention. As shown in FIG. 1, a plasma display panel of the present invention includes a pair of transparent electrodes 180a and 180b and a bus electrode on an upper plate 170. A pair of sustain electrodes consisting of 180a 'and 180b') is formed.

The dielectric layer 190 and the passivation layer 195 are sequentially formed on the entire upper plate 170 while covering the sustain electrode pairs.

The upper plate 170 may be formed by processing, for example, milling and cleaning the glass for the display substrate.

In addition, the transparent electrodes 180a and 180b may be formed of indium tin oxide (ITO), SnO 2, or the like, and may be formed by a photoetching method by sputtering or a lift-off method by CVD. It can be formed as.

Subsequently, the bus electrodes 180a 'and 180b' may include a general-purpose conductive metal and a noble metal.

Here, general purpose conductive metals include Al (aluminum), Cu (copper), Ni (nickel), Cr (chromium), Mo (molybdenum), and the like, and the precious metals are Ag (silver), Au (gold), Pt. (Platinum), Ir (iridium), and the like.

Next, when mixing the general purpose metal and the precious metal, a core may be formed of the general purpose metal and the surface of the core may be wrapped with the precious metal.

In addition, a transparent dielectric layer 190 is formed on the upper plate 170 on which the transparent electrode and the bus electrode are formed, and a protective film 195 is formed on the transparent dielectric layer 190, and the transparent dielectric layer 190 is protected from the impact of (+) ions during discharge. ) And increase secondary electron emission.

In addition, the protective film 195 can suppress an increase in jitter phenomenon and afterglow erroneous discharge due to discharge delay even when used for a long time.

Here, the protective film 195 may include a powder having at least two or more crystals having different recrystallization growth rates.

That is, the protective film 195 may include a mixed powder obtained by mixing a first powder having a crystal composed of a (100) plane and a second powder having a crystal including at least one (111) plane.

In this case, the second powder may be made of any one of a first crystal composed of a (111) plane, a second crystal composed of a (100) plane and a (111) plane, and a mixed crystal in which the first crystal and the second crystal are mixed.

FIG. 2 is a view showing crystals included in the passivation layer 195 of FIG. 1. As shown in FIG. 2, a first crystal composed of a (111) plane is an octahedron-shaped crystal (100). The second crystal composed of the) plane and the (111) plane may be one of truncated cube, cubeoctahedron, and truncated octahedron shapes.

In the protective film 195, the content of the second powder having a crystal including at least one (111) plane is preferably about 5-95%, and most preferably about 40-60% of the total mixed powder. Is good.

When the content of the second powder is less than about 5% with respect to the total mixed powder, afterglow misdischarge is increased when the panel is used for a long time, and when the content of the second powder is about 95% or more with respect to the total mixed powder, the discharge when the panel is used for a long time Problems with increased latency may also occur.

The first and second powders of the mixed powder included in the protective film 195 may be at least one of a single crystal and a polycrystalline MgO powder.

In addition, in the mixed powder contained in the protective film 195 of this invention, the recrystallization growth rate of a 2nd powder shall be faster than the recrystallization growth rate of a 1st powder.

The thickness of the protective film 195 is preferably about 300 to 950 nm, but is not limited to this value.

3 is a cross-sectional view illustrating the protective film structure of FIG. 1 in detail.

The structure of the protective film shown in FIG. 3 is an embodiment of the present invention, but is not limited thereto.

That is, the structure of the protective film may be formed of not only the two-layer structure of FIG. 3 but also a single layer or two or more layers.

As shown in FIG. 3, the protective film 195 of the present invention is composed of a first layer 195a and a second layer 195b.

Here, the first layer 195a is formed on the transparent dielectric layer 190 of the upper plate 170 and includes MgO. Similar to the composition of the conventional protective film, at least one of single crystal MgO or polycrystalline MgO may be formed. It is made to include.

The second layer 195b is formed on the first layer 195a and has a first MgO powder having a crystal composed of a (100) plane and a second MgO powder having a crystal including at least one (111) plane. It consists of a mixed powder mixed with.

Here, the second layer 195b is pulverized MgO having a crystal composed of the (100) plane and MgO having a crystal including the at least one (111) plane, and then mixed and press-molded them. It can be prepared by sintering.

That is, the protective film 195 of this invention consists of a structure in which the sintered compact of the mixed powder which is the 2nd layer 195b was apply | coated on the 1st layer 195a.

In this case, the thickness of the first layer 195a may be about 300 to 750 nm, and the thickness of the second layer 195b may be about 5 to 200 nm.

In addition, the application rate of the mixed powder formed on the first layer 195a is preferably about 0.1-20% relative to the entire upper area of the first layer 195a, and the most preferable application rate of the mixed powder is about 0.5-1. 1.5% is good.

4A and 4B are graphs showing jitter and high temperature margin values according to application rates of the mixed powder used in the protective film.

Figure 4a is a measurement of the discharge delay time, i.e., jitter, when the application rate is different when the mixed powder of the first powder and the second powder 1: 1 mixed on the MgO layer is applied.

As shown in Fig. 4A, when the application rate of the mixed powder is about 0.1-2%, the jitter decreases rapidly and then gradually decreases when the application rate is about 2%-20%.

4B illustrates an address voltage margin at high temperature according to a case where the application rate is different when a mixed powder obtained by mixing a 1: 1 powder of a first powder and a second powder is applied on an MgO layer.

As shown in FIG. 4B, it can be seen that when the application rate of the mixed powder is about 0.1-20%, the address voltage margin does not decrease.

In general, when the plasma display panel discharges, secondary electron emission and exo-electron emission occur to reduce the discharge voltage and improve the discharge delay.

However, as the discharge delay time, i.e., the jitter decreases, the amount of exo-electron emission increases, so that the wall voltage is lost at a high temperature, thereby reducing the address voltage margin.

Therefore, by determining the coating rate of the mixed powder through the experimental data of FIGS. 4A and 4B, a protective film capable of reducing jitter and afterglow erroneous discharge without reducing address voltage margin can be manufactured.

In addition, the protective film 195 of the present invention may be doped with at least one dopant selected from Al, B, Ba, Ca, Cr, Fe, Ge, Ga, In, Mn, Ni, P, Sc, Si, Y. .

Here, the concentration of the dopant is preferably about 10-10000 ppm relative to the total weight of the protective film 105.

The reason for doping such a dopant in the protective film 195 is that it can facilitate the emission of secondary electrons and exo-electrons.

As described above, since the emission of secondary electrons and exo-electrons can reduce jitter for discharge delay, doping of the dopant to the protective film 195 facilitates the emission of secondary electrons and exo-electrons by jitter. There is an effect to reduce.

On the other hand, the address electrode 120 is formed on the lower plate 110 along the direction crossing the sustain electrode pair, and the white dielectric layer 130 is formed on the entire surface of the lower plate 110 while covering the address electrode 120.

Here, the address electrode 120 may be formed of a general-purpose conductive metal and a noble metal as in the above-described bus electrode, and the general-purpose conductive metal may include Al (aluminum), Cu (copper), Ni (nickel), and Cr ( Chromium), Mo (molybdenum), and the like, and noble metals include Ag (silver), Au (gold), Pt (platinum), Ir (iridium), and the like.

In addition, the white dielectric layer 130 may be applied by a printing method or a film laminating method using a lead-free dielectric composition such as the transparent dielectric layer 190 of the upper plate 170, and then may be completed through a firing process. The barrier rib 140 is formed on the white dielectric layer 130 to be disposed between the address electrodes 120.

Next, the partition wall 140 may be stripe-type, well-type, or delta-type.

The partition wall 140 may be fabricated using a lead-free dielectric composition such as the transparent dielectric layer 190 of the upper plate 170. Although not illustrated, a black top may be formed on the partition wall 140.

The phosphor layers 150a, 150b, and 150c of red (R), green (G), and blue (B) are formed in the discharge cells between the partition walls 140.

Here, the phosphor layer of at least one discharge cell among the red, green, and blue discharge cells may be different from the discharge cells having different thicknesses.

For example, the thicknesses of the green and blue phosphor layers 150b and 150c may be thicker than the thicknesses of the red phosphor layer 150a, and the thicknesses of the green and blue phosphor layers 150b and 150c may be the same or different. .

Next, the upper plate 170 and the lower plate 110 are bonded to each other with the partition wall 140 interposed therebetween, and are bonded through a sealing material provided on the outer side of the substrate.

At this time, the point where the address electrode 120 on the lower plate 110 and the sustain electrode pair on the upper plate 170 cross each other constitutes a discharge cell.

The upper plate 170 and the lower plate 110 may be connected to and driven by the driving device.

Thus, the plasma display panel of the present invention constituted is a mixture of a first powder having a crystal composed of a (100) plane and a second powder having a crystal including at least one (111) plane in a protective film 195. By suppressing the recrystallization growth of the first powder having an effect of improving the discharge delay and promoting the recrystallization of the second powder having an effect of improving the afterglow discharging, the discharge delay phenomenon and the afterglow of the long-term use There is an effect that can block the previous increase.

5A to 5D are graphs comparing high-temperature voltage margin, jitter, misdischarge intensity, and misdischarge density of a plasma display panel having a protective film manufactured under the first, second, and third conditions.

Here, the first protective film manufactured under the first condition is an MgO protective film manufactured under the same condition as before, and the second protective film manufactured under the second condition has a crystal composed of (100) planes on the first protective film under the first condition. A protective film coated with MgO powder at a coating rate of about 0.5-1.5%.

The third protective film manufactured under the third condition has a first MgO powder having a crystal composed of (100) planes and a second having a crystal including at least one (111) plane on the first protective film under the first condition. A protective film obtained by applying a mixture of Mg0 powder in a ratio of 1: 1 at a coating rate of about 0.5-1.5%.

In this way, the driving conditions of the respective plasma display panels having the protective film produced under the three conditions were driven in the same manner.

FIG. 5A is a graph comparing high-temperature voltage margins of the first, second and third passivation layers. As shown in FIG. 5A, the third passivation layer of the present invention is compared with the sustain and address voltage margins of the first and second passivation layers. It can be seen that the degree of reduction is not large.

As described above, although the decrease in the high temperature voltage margin is inevitable due to the jitter reduction effect, the third protective film of the present invention does not have a large decrease in the high temperature voltage margin, and thus has an effect of blocking the increase in the afterglow false discharge caused by long time use. have.

5B is a view showing jitter values of the first, second, and third passivation layers according to the driving time, and as shown in FIG. 5B, the second and third passivation layers have lower jitter values than the first passivation layer. Therefore, there is an effect that can reduce the discharge delay time.

5C and 5D are diagrams illustrating erroneous discharge intensity and erroneous discharge density of the first, second, and third passivation layers according to the driving time, and as shown in FIGS. 5C and 5D, The erroneous discharge strength and density of the third protective film are greater than the erroneous discharge strength and density of the first protective film and smaller than the erroneous discharge strength and density of the second protective film.

That is, the third protective film of the present invention has the advantage of reducing the jitter value and reducing the afterglow erroneous discharge.

As described above, when the protective film of the present invention is prepared by applying only the MgO powder having a crystal composed of (100) planes on the existing MgO protective film, there is an improvement effect of jitter such as discharge delay, but there is no improvement effect of afterglow misdischarge. In order to compensate for this, by applying a mixture of MgO powder having a crystal consisting of (100) plane and MgO powder having a crystal comprising at least one (111) plane on the existing MgO protective layer, There is an effect that can block the increase in the discharge delay phenomenon and afterglow mis-discharge according to.

The reason is that the recrystallization of the MgO powder having the crystal composed of the (100) plane having the effect of improving the discharge delay is suppressed, and the recrystallization of the MgO powder having the crystal containing the (111) plane having the effect of improving the afterglow misdischarge. Since it can promote growth, there was an effect that can block the increase in the discharge delay phenomenon and the afterglow erroneous discharge caused by long time use.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

1 illustrates a plasma display panel according to the present invention.

FIG. 2 illustrates crystals included in the passivation layer 195 of FIG. 1.

3 is a cross-sectional view showing in detail the protective film structure of FIG.

4A and 4B are graphs showing jitter and high temperature margin values according to the application rate of the mixed powder used in the protective film.

5A is a graph comparing high-temperature voltage margins of the first, second and third passivation layers.

5B is a graph showing jitter values of the first, second, and third passivation layers according to the driving time.

5C is a graph showing mis-discharge intensity of the first, second, and third passivation layers according to the driving time

5D is a graph showing misdischarge densities of the first, second and third passivation layers according to the driving time.

Claims (13)

A first substrate having an address electrode, a first dielectric layer and a partition wall; A second substrate having a sustain electrode pair, a second dielectric layer, and a protective film, the second substrate being coupled to the first substrate with the barrier ribs interposed therebetween, The protective film includes a powder having at least two crystals having different recrystallization growth rates. 2. The protective film of claim 1, wherein the protective film includes a mixed powder obtained by mixing a first powder having a crystal composed of a (100) plane and a second powder having a crystal including at least one (111) plane. Plasma display panel. 3. The second powder of claim 2, wherein the second powder comprises a first crystal composed of a (111) plane, a second crystal composed of a (100) plane and a (111) plane, and a mixed crystal in which the first crystal and the second crystal are mixed. Plasma display panel comprising any one. The crystal of claim 3, wherein the first crystal is an octahedron shape crystal, and the second crystal is a truncated cube, a cubeoctahedron, or a truncated octaheadron. (truncated octahedron) A plasma display panel, characterized in that the crystal of any one. 3. The plasma display panel of claim 2, wherein the content of the second powder having a crystal including the at least one (111) plane is 5-95% of the total mixed powder. The plasma display panel of claim 2, wherein the first and second powders comprise at least one of a single crystal and a polycrystalline MgO powder. The plasma display panel of claim 2, wherein the recrystallization growth rate of the second powder is faster than the recrystallization growth rate of the first powder. The plasma display panel of claim 1, wherein the passivation layer has a thickness of 300 nm to 950 nm. The method of claim 1, wherein the protective film A first layer formed over the second dielectric layer and comprising MgO; A second layer comprising a mixed powder formed on the first layer and mixing a first MgO powder having a crystal composed of (100) planes and a second MgO powder having a crystal comprising at least one (111) plane Plasma display panel, characterized in that consisting of. 10. The plasma display panel of claim 9, wherein the thickness of the first layer is 300-750 nm and the thickness of the second layer is 5-200 nm. 10. The plasma display panel of claim 9, wherein a coating rate of the mixed powder formed on the first layer is 0.1-20% of the total area of the upper portion of the first layer. The method of claim 1, wherein the protective layer is doped with at least one dopant selected from Al, B, Ba, Ca, Cr, Fe, Ge, Ga, In, Mn, Ni, P, Sc, Si, Y Plasma display panel. The plasma display panel of claim 12, wherein the concentration of the dopant is 10-10000 ppm with respect to the total weight of the protective layer.

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