KR20060062699A - Plasma display panel - Google Patents

Abstract

According to the present invention, a plasma display panel includes a front substrate and a rear substrate disposed to face each other, a front dielectric layer and a rear dielectric layer formed on the rear surface of the front substrate and the front surface of the rear substrate, and spaced apart from each other in the rear dielectric layer. A plurality of address electrodes arranged in such a manner as to be provided, and a plurality of address electrodes extending in a direction crossing the address electrodes and provided in the front dielectric layer, and a surface facing the rear substrate is formed with a convex curved surface to the rear; And a partition wall disposed between the front substrate and the rear substrate and partitioning a plurality of discharge cells in which discharge is performed, and a phosphor layer disposed in each of the discharge cells. This improves the discharge characteristics of the plasma display panel and reduces the manufacturing cost.

Description

Plasma display panel {Plasma display panel}

1 is a perspective view showing an example of a conventional plasma display panel.

FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1.

3 is a perspective view illustrating a plasma display panel according to an embodiment of the present invention.

4 is a cross-sectional view taken along the line III-III of FIG. 3.

5 is a cross-sectional view taken along the line IV-IV of FIG. 3.

<Description of the symbols for the main parts of the drawings>

10 ... front substrate 11 ... front dielectric layer

20 back substrate 21 back dielectric layer

22.Address electrode 30 ... Protective layer

40 ... Holding electrode pair 41 ... X electrode

42 ... Y electrode 41a, 42a ... transparent electrode

41b, 42b ... bus electrodes 41c, 42c ... curved surface of transparent electrode

50.Bulk wall 51.Discharge cell

52 ... phosphor layer 1, 100 ... plasma display panel

222 curved surface of the address electrode 501 vertical bulkhead

502.Vertical bulkhead

The present invention relates to a plasma display panel, and more particularly, to a plasma display panel having an improved structure such that the discharge characteristics of the plasma display panel are improved as well as the manufacturing cost is reduced.

In general, a plasma display panel is a flat panel display device that displays an image by using a gas discharge phenomenon, and is a thin flat panel display device that is thin in size and has a large viewing angle with a wide viewing angle. I am in the limelight. In such a plasma display panel, a discharge is generated in a discharge cell filled with a discharge gas by a direct current or an alternating voltage applied between electrodes, and ultraviolet rays emitted from the discharge gas excite a phosphor to emit visible light, thereby generating an image. Implement

1 is a perspective view showing an example of a conventional plasma display panel, and FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1.

1 and 2, a conventional plasma display panel 1 includes a front substrate 70 and a rear substrate 90 disposed to face each other, a rear surface of the front substrate 70, and the rear substrate 90. ) Between the front dielectric layer 71 and the back dielectric layer 91 formed on the front surface of the?, The address electrodes 92 disposed in the back dielectric layer 91, and the front substrate 70 and the rear substrate 90, respectively. A discharge cell 93 disposed to generate a discharge, a phosphor layer 94 disposed in the discharge cell 93, and a plurality of sustain electrode pairs 80 disposed on the front dielectric layer 71.

Each of the sustain electrode pairs 80 includes an X electrode 81 and a Y electrode 82 that extend in a direction crossing each of the address electrodes 92 and are spaced apart from each other. The X electrode 81 and the Y electrode 82 are transparent electrodes 81a and 82a made of indium tin oxide (ITO) and the like, and bus electrodes connected to one side of the transparent electrodes 81a and 82a. 81b and 82b).

The front dielectric layer 71 and the back dielectric layer 91 are generally used to protect the sustain electrode pair 80 and the address electrode 92 from charged particles during discharge. ) To a thickness of 40 µm and 15 µm or more, respectively.

On the other hand, the bus electrodes 81b and 82b are generally formed by a photo etching method or the like. In such a photoetching method, chromium / copper / chromium is deposited, and then a predetermined functional material is dispersed in the photoresist, and then a binder, a dispersant, a surfactant, a photosensitizer and the like are added to make a photosensitive paste. Thereafter, the photosensitive paste is coated and dried to cover the deposited chromium / copper / chromium, and then exposed and developed through an exposure photomask having a predetermined pattern to form a desired pattern. After the desired pattern is formed, bus electrodes 81b and 82b are finally formed through a drying and firing process.

On the other hand, in the exposure and development processes as described above, the developer is penetrated in both sides of the bus electrodes 81b and 82b in contact with the transparent electrodes 81a and 82a, that is, in the direction indicated by the arrow p in FIG. Both sides are overetched. Due to such overetching, both sides of the bus electrodes 81b and 82b undergo a firing process, which is the final process, in a state where they are not bonded to the transparent electrodes 81a and 82a. In this firing process, the bus electrodes 81b and 82b are contracted, and in particular, the center portion bonded to the transparent electrodes 81a and 82a is contracted toward the transparent electrode, so that both sides which are not joined to the transparent electrode are relatively spaced apart from the transparent electrode. It is formed by being rolled backwards, that is, backward. Through such a process, the bus electrodes 81b and 82b have the shape of edge curls which are rolled toward the rear substrate 90 as shown in FIG. 2.

In addition, the address electrode 92 is also formed through the above-described process, and overetching occurs on both sides of the surface of the address electrode facing the back substrate 90. Thus, the address electrode 92 The edge curl as described above is also present on both sides.

However, as described above, edge curls are formed on the bus electrodes 81b and 82b, and the front dielectric layer 71 has a minimum of 40 from all surfaces of the bus electrodes 81b and 82b in order to protect the sustain electrode pair 80. Since the thickness must be greater than or equal to μm, the front dielectric layer 71 should be formed with a thickness of at least 40 μm from the edge curls of the bus electrodes 81b and 82b. Similarly, the back fluid layer 91 should be formed to have a thickness of at least 15 μm from the edge curl of the address electrode 92. As described above, since the edge curl increases the thickness of the front dielectric layer and the rear dielectric layer than the case where the edge curl is not formed, there is a problem of lowering the discharge characteristics of the plasma display panel such as increasing the discharge voltage. In particular, in the case where the thickness of the front dielectric layer is thick, not only the voltage applied during the sustain discharge is increased more than necessary, but also the transmittance of visible light generated during the discharge is significantly reduced due to the increase in the thickness of the front dielectric layer, so that the luminance is increased. There is a problem falling. In addition, since the electric field is concentrated at the edge portion, the front dielectric layer and the back dielectric layer are easily damaged during discharge, resulting in a significant decrease in durability of the plasma display panel.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a plasma display panel having an improved structure such that the discharge characteristics of the plasma display panel are improved and manufacturing costs are reduced by convexly forming the surface of the sustain electrode. To provide.

In order to achieve the above object, the plasma display panel according to the present invention, the front substrate and the rear substrate disposed to face each other, the front dielectric layer and back dielectric layer formed on the back surface of the front substrate and the front surface of the back substrate, respectively, A plurality of address electrodes arranged side by side and spaced apart from each other in the rear dielectric layer and extending in a direction crossing the address electrodes are provided in the front dielectric layer, and the surface facing the rear substrate is formed with a convex curved surface to the rear. And a partition wall provided between the sustain electrode, the front substrate and the rear substrate, and partitioning a plurality of discharge cells in which discharge is performed, and a phosphor layer disposed in each discharge cell. do.

According to the present invention, the sustain electrode has a transparent electrode protruding to the center of each discharge cell, and a bus electrode electrically connected to the transparent electrode, the surface of the bus electrode toward the rear substrate side is rearward It is preferable that it is formed in the convex curved surface with respect to.

Further, according to the present invention, it is preferable that the surface of the address electrode facing the front substrate is formed with a curved surface that is convex toward the front side.

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

3 is a perspective view illustrating a plasma display panel according to an embodiment of the present invention, FIG. 4 is a cross-sectional view taken along the line III-III of FIG. 3, and FIG. 5 is a cross-sectional view taken along the line IV-IV of FIG. 3.

3 to 5, the plasma display panel 100 according to the present embodiment includes a front substrate 10 and a back substrate 20, a front dielectric layer 11 and a back dielectric layer 21, and an address electrode 22. And a sustain electrode pair 40, a partition 50, and a phosphor layer 52.

The front substrate 10 and the rear substrate 20 are disposed to face each other, and the front substrate 10 is formed of a transparent material such as glass that can transmit visible light so that an image is displayed.

The front dielectric layer 11 and the back dielectric layer 21 are formed on the back surface of the front substrate 10 and the front surface of the back substrate 20, respectively. The front dielectric layer 11 and back dielectric layer 21 are each made of a dielectric such as PbO, B ₂ O ₃ , SiO _2, and the like. A protective layer 30 made of a material such as MgO is formed on the rear surface of the front dielectric layer 11. The protective layer 30 protects the front dielectric layer 11 from collision of charged particles accelerated during discharge, in particular during sustain discharge which displays the gray scale of the plasma display panel 100, and emits secondary electrons. In addition to increasing the discharge amount in the discharge cell 51 serves to lower the discharge voltage.

The address electrodes 22 are arranged on the rear substrate 20 so as to be spaced apart from each other and have a stripe shape. The surface of the address electrode 22 facing the front substrate 10 is formed as a curved surface 222 convex toward the front as shown in FIG. That is, the center of curvature of the curved surface 222 is located behind the curved surface 222. The address electrodes 22 are covered by the back dielectric layer 21 and embedded therein, and a partition 50, which will be described later, is formed between the address electrodes 22 on the top of the back dielectric layer 21.

The plurality of sustain electrode pairs 40 are arranged on a surface of the front substrate 10 facing the rear substrate 20. Each of the sustain electrode pairs 40 extends in a direction crossing the address electrodes 22 and is disposed in the front dielectric layer 11. Each of the sustain electrode pairs 40 includes a pair of sustain electrodes 41 and 42 spaced apart from each other, and the sustain electrodes 41 and 42 are distinguished by the X electrode 41 and the Y electrode 42, respectively. The X electrode 41 and the Y electrode 42 can act as a common electrode and a scan electrode, respectively.

The X electrode 41 and the Y electrode 42 include transparent electrodes 41a and 42a and bus electrodes 41b and 42b connected to one side of the transparent electrodes 41a and 42a. . The transparent electrodes 41a and 42a are formed of indium tin oxide (ITO), which is a transparent conductor in order to transmit visible light. In addition, the bus electrodes 41b and 42b apply voltages to the transparent electrodes 41a and 42a, respectively, and the electrical resistance of the transparent electrodes 41a and 42a formed of ITO having relatively low electrical conductivity. In order to improve the resistance, the conductive layer is formed of a metal having excellent conductivity such as silver (Ag) or copper (Cu).

The X electrodes 41 are spaced apart from each other and are transparent electrodes 41a protruding toward the center of each discharge cell 51 to be described later, and bus electrodes 41b electrically connected to one side of the transparent electrodes 41a. It is provided. Likewise, the Y electrode 42 is also spaced apart and protrudes to the center of each of the discharge cells 51 to be described later to be disposed in parallel with the transparent electrodes 41a of the X electrode 41. Transparent electrodes 42a and bus electrodes 42b electrically connected to one side of the transparent electrodes 42a. The bus electrodes 41b and 42b extend in directions crossing the address electrodes 22, respectively, and are disposed in discharge cells 51 arranged in a direction orthogonal to the direction in which the address electrodes 22 extend. The transparent electrodes 41a and 42a are connected to each other.

The surface facing the rear substrate 20 of the sustain electrodes 41 and 42 is formed to have a curved surface that is convex with respect to the rear side. In this embodiment, the rear substrate 20 of the bus electrodes 41b and 42b is formed. The surface facing to the side is formed of curved surfaces 41c and 42c which are convex with respect to the rear side. That is, as shown in FIG. 4, the centers of curvature of the curved surfaces 41c and 42c of the bus electrodes 41b and 42b are located in front of the curved surfaces 41c and 42c. As such, in order to convexly form the surfaces of the bus electrodes 41b and 42b, an offset method may be used.

That is, a conductive ink composition is prepared by dispersing or dissolving metal powders such as silver (Ag) and copper (Cu), and binder resins such as thermosetting resins such as phenol resins and melamine resins and thermoplastic resins such as polyester resins. And mounting the conductive ink composition on a concave substrate having concave portions formed in the patterns of bus electrodes 41b and 42b, passing the conductive ink composition over the concave portion while pressing the conductive ink composition with a blade to form the conductive ink in the concave portion. Fill the composition in an amount. Thereafter, the transfer roller is moved onto the concave substrate to transfer the conductive ink composition in the concave portion to the surface of the transfer roller, and then the transfer roller is transferred to the rear surface of the transparent electrode, followed by a firing step. Through the above-described process, the bus electrodes 41b and 42b having a desired thickness can be formed at a time by adjusting the depth of the recesses. In addition, since the conductive ink composition is formed in a liquid phase, and the liquid phase is formed in a curved surface to minimize surface tension, the surface facing the rear substrate 20 of the bus electrodes 41b and 42b is convex, curved surface 41c. , 42c).

When the above-described offset method is applied in the same manner in the process of forming the address electrode 22, each of the address electrodes 22 can also be easily convex on the surface facing the rear substrate 20.

The partition wall 50 partitions the discharge cell 51. The discharge cells 51 are partitioned by the partition walls 50 and are provided between the front substrate 10 and the rear substrate 20. The discharge is generated inside the discharge cell 51 to implement an image. In the present exemplary embodiment, the discharge cells 51 include a plurality of horizontal partition walls 501 disposed in parallel with the address electrode 22, and a plurality of vertical walls disposed in parallel with each other and crossing the horizontal partition walls 501. The partition 502 is provided.

The phosphor layer 52 is disposed in each of the discharge cells 51. The phosphor layer 52 is formed on the inner surface of the barrier rib 50 and the upper surface of the back dielectric layer 21 surrounded by the barrier rib 50. The color of the phosphor layer 52 is roughly divided into red, green, and blue to realize an image. Each discharge cell 51 is filled with a discharge gas mixed with neon (Ne), xenon (Xe), and the like, and the phosphor layer 52 emits visible light by being excited by ultraviolet rays generated during discharge.

Unlike the conventional plasma display panel 1, the plasma display panel 100 configured as described above does not have sharp edge curls formed on the bus electrodes 41b and 42b and the address electrode 22, so that electric fields are not concentrated. Do not. Therefore, the possibility that the front dielectric layer 11 and the back dielectric layer 21 are damaged during discharge is significantly lowered.

In addition, the plasma display panel 100 has curved surfaces of the bus electrodes 41b and 42b and the surface of the address electrode 22 to reduce the thickness of the front dielectric layer 11 and back dielectric layer 21. Even with this, the breakdown voltage characteristics and luminance characteristics are improved. The improvement of the breakdown voltage characteristics and luminance characteristics can be seen through the breakdown voltage and luminance values recorded in the following [Table 1]. As shown in Table 1, in the case of the plasma display panel 100 having the surfaces facing the rear substrates 20 of the bus electrodes 41b and 42b as curved surfaces 41c and 42c, the front dielectric layer ( The withstand voltage and luminance value according to the thickness change of 11) are recorded.

 division  Conventional  Experiment 1  Experiment 2  Experiment 3  Experiment 4  Experiment 5  Experiment 6  Experiment 7  Experiment 8 Dielectric layer thickness (㎛)  40  38  36  34  32  30  28  26  24 Bus electrode thickness (㎛)  5  Withstand voltage (V)  900  972  960  946  935  929  918  907  889  Brightness (cd)  930  934  943  947  952  959  965  971  980

As shown in FIG. 4, the shortest distance b from the curved surfaces 41c and 42c of the bus electrodes 41b and 42b to the surface facing the rear substrate 20 of the front dielectric layer 11 is shown in Table 1 below. It is preferable that it is 26 micrometers-36 micrometers as recorded in the]. When the shortest distance b of the bus electrode is less than 26 μm, the brightness of the front electrode layer is 40 μm, which is improved in brightness, but applied to the sustain electrode pair without damaging the front dielectric layer. The potential voltage, i.e., the withstand voltage, is rather undesired since it is more likely to break the front dielectric layer during discharge. In addition, when the shortest distance b of the bus electrode exceeds 36 mu m, it is not preferable because the effect of luminance improvement is inferior as compared with the conventional plasma display panel 1.

In addition, as shown in FIG. 4, the ratio (a / b) of the shortest distance b of the bus electrode and the maximum thickness a of the bus electrode toward the rear substrate toward the rear substrate (a / b) is preferably 5.2 to 7.2. Do. This is because the thickness of the bus electrode in Table 1 is 5 μm, and as described above, the shortest distance b of the bus electrode is preferably 26 μm to 36 μm.

According to the present invention having the above-described configuration, the surface facing the rear substrate side of the bus electrode is formed as a convex curved surface, so that no electric field is concentrated on the curved surface. Thus, the possibility of breaking the front dielectric layer upon discharge is significantly reduced. In addition, even if the thickness of the front dielectric layer is reduced, the breakdown voltage characteristics and luminance characteristics are improved. In addition, since the thickness of the front dielectric layer is reduced, the manufacturing cost is also reduced.

Although the present invention has been described in detail with reference to preferred embodiments, the present invention is not limited to the above embodiments, and many modifications can be made by those skilled in the art within the technical idea of the present invention. It is obvious.

Claims (3)

A front substrate and a rear substrate disposed to face each other; A front dielectric layer and a back dielectric layer formed on the back surface of the front substrate and the front surface of the back substrate, respectively; A plurality of address electrodes spaced apart from each other in the rear dielectric layer; A sustain electrode extending in a direction intersecting with the address electrode and provided in the front dielectric layer, and having a surface facing the rear substrate toward a rear surface thereof; A partition wall disposed between the front substrate and the rear substrate and partitioning a plurality of discharge cells in which discharge is performed; And And a phosphor layer disposed in each of the discharge cells. The method of claim 1, The sustain electrode has a transparent electrode protruding to a central portion of each discharge cell, and a bus electrode electrically connected to the transparent electrode, And the surface of the bus electrode facing the rear substrate is formed with a curved surface that is convex toward the rear. The method of claim 1, And the surface of the address electrode facing the front substrate is formed with a curved surface that is convex toward the front side.

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