JP2004247295A - Plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasma display panel provided with a multi-layered structure dielectric layer in which few bubbles are contained. <P>SOLUTION: As for this plasma display panel 1 in which a first dielectric layer 7 to cover a display electrode 6 composed of a scanning electrode 4 and a sustaining electrode 5 and/or a second dielectric layer 12 to cover a data electrode 11 are made as a multi-layered structure, the upper layer of the multi-layered structure does not cover the edge of the lower layer. By this, the bubbles, which are usually involved between the edge part of the lower layer and the upper layer because it is formed in a state that the edge of the lower layer is covered when forming the upper layer, are not involved, and the plasma display panel provided with the multi-layered structure dielectric layer having few involved bubbles is realized. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a plasma display panel known as a display device.

  In a plasma display panel (PDP), an image is displayed by generating ultraviolet rays by gas discharge and exciting a phosphor with the ultraviolet rays to emit light.

  Such a PDP can display at a higher speed than a liquid crystal panel, has a wide viewing angle, is easy to increase in size, and has a high display quality because it is a self-luminous type. In recent years, panel displays have attracted particular attention, and have been used for various purposes as display devices in places where many people gather and display devices for enjoying large-screen images at home.

  PDPs are roughly classified into AC type and DC type in terms of driving, and there are two types of discharge types: surface discharge type and counter discharge type. However, due to higher definition, larger screen and simpler structure, In this case, a surface discharge type AC PDP having a three-electrode structure is mainly used. The structure will be described with reference to FIG.

  The front plate 22 of the PDP 21 has a display electrode 26 including a scan electrode 24 and a sustain electrode 25 on a transparent and insulating front substrate 23 such as glass, and a first dielectric layer 27 covering the display electrode 26. Further, a protective layer 28 made of an MgO film is provided to cover the protective layer. Here, the scan electrode 24 and the sustain electrode 25 have, for example, a structure in which bus electrodes 24b and 25b made of a metal material are stacked on the transparent electrodes 24a and 25a from the viewpoint of securing light transmission and reducing electric resistance. Further, the first dielectric layer 27 is formed by applying a paste-like dielectric material containing a powder of a low-melting glass material by screen printing or a die coating method and drying it, or by forming a sheet-like dielectric film. It is formed by a method of transferring, attaching and baking.

  The back plate 29 includes a data electrode 31, a second dielectric layer 32 covering the data electrode 31, a partition wall 33 parallel to the data electrode 31, and a second dielectric The phosphor layers 34R, 34G, and 34B are provided on the surface of the layer 32 and the side surfaces of the partition walls 33. Here, similarly to the first dielectric layer 27, the second dielectric layer 32 is formed by applying a paste-like dielectric material containing a powder of a low-melting glass material by screen printing or a die coating method and then drying. Alternatively, it is formed by a method in which a dielectric film in the form of a sheet is transferred and attached, and then fired.

  The front plate 22 and the back plate 29 are arranged opposite to each other with the discharge space 35 interposed therebetween so that the display electrodes 26 and the data electrodes 31 are orthogonal to each other, and are sealed by a seal material formed on the peripheral edge. The discharge space 35 is filled with at least one rare gas of helium, neon, argon, and xenon as a discharge gas. The discharge space 35 is partitioned by a partition wall 33 and intersected by the display electrode 26 and the data electrode 31. Discharge space 35 operates as a discharge cell 36.

In the above configuration, the first dielectric layer 27 and / or the second dielectric layer 32 may have a multilayer structure. The purpose is, for example, by using a material having a high glass softening point for the lower layer and using a material having a low glass softening point for the upper layer, thereby covering defects such as pinholes generated when forming the lower layer with the upper layer, and insulating the upper layer. It is possible to improve the breakdown voltage, or to form the first dielectric layer 27 and / or the second dielectric layer 32 in a single application instead of forming them in a single application, and to apply them in a number of layers to achieve a predetermined thickness. Thus, the surface roughness can be improved (for example, see Non-Patent Document 1).
2001 FPD Technology Taizen, Electronic Journal Co., Ltd., October 25, 2000, p594-p597

  However, despite the fact that the first dielectric layer 27 and / or the second dielectric layer 32 are formed as described above, convex bulges are formed on the surface and the surface roughness is not good. There has been a case where a problem or a problem that the withstand voltage is reduced due to generation of a pinhole occurs.

  As a result of the study by the present inventors on this problem, the following has been found. In other words, when forming the first dielectric layer 27 and / or the second dielectric layer 32 having the above-described laminated structure, if the upper layer is formed while covering the lower layer edge, 6 shows a cross-sectional view of the end portion of the PDP 21 using, for example, the first dielectric layer 27 as an example. The bubble 101 is caught between the edge portion of the lower layer 27a and the upper layer 27b. In such a case, a gap may be formed. In such a case, the bubble 101 expands in the subsequent firing, so that the first dielectric layer 27 swells 102 as shown in FIG. As shown in FIG. 8, pinholes 103 may be generated in the upper layer 27b as a result of the bulging burst, and as a result, the first dielectric layer 27 has a low withstand voltage. Such a problem is also found in the second dielectric layer 32.

  The present invention has been made in view of such a situation, and an object of the present invention is to provide a plasma display panel including a dielectric layer having a multilayer structure in which inclusion of bubbles is suppressed, and capable of performing favorable image display. With the goal.

  In order to achieve the above object, a plasma display panel according to the present invention is a plasma display panel having a first dielectric layer covering a display electrode composed of a scan electrode and a sustain electrode, and a second dielectric layer covering a data electrode. , Wherein the first dielectric layer and / or the second dielectric layer has a multilayer structure, and the upper layer does not cover the lower layer.

  According to the present invention, it is possible to realize a plasma display panel capable of displaying a good image by including a dielectric layer having a multilayer structure in which inclusion of bubbles is suppressed.

  That is, the invention according to claim 1 of the present invention relates to a plasma display panel having a first dielectric layer covering a display electrode composed of a scan electrode and a sustain electrode, and a second dielectric layer covering a data electrode. A plasma display panel, wherein the first dielectric layer and / or the second dielectric layer has a multilayer structure, and the upper layer does not cover the lower layer.

  Hereinafter, a plasma display panel according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a sectional perspective view showing a schematic configuration of an image display section of a plasma display panel according to one embodiment of the present invention.

  The front panel 2 of the PDP 1 has a display electrode 6 including a scan electrode 4 and a sustain electrode 5 on a transparent and insulating front substrate 3 such as glass, and a first dielectric layer 7 covering the display electrode 6. Further, a protective layer 8 made of an MgO film is provided to cover the protective layer. Here, the scanning electrode 4 and the sustaining electrode 5 have a structure in which, for example, bus electrodes 4b and 5b made of a metal material are stacked on the transparent electrodes 4a and 5a from the viewpoint of securing light transmission and reducing electric resistance. The first dielectric layer 7 is formed by applying a paste-like dielectric material containing a powder of a low-melting glass material by screen printing or a die coating method and drying it, or by forming a sheet-like dielectric film. It is formed by a method of transferring, attaching and baking.

  The back plate 9 includes a data electrode 11, a second dielectric layer 12 covering the data electrode 11, a partition wall 13 parallel to the data electrode 11, a second dielectric The phosphor layers 14R, 14G, and 14B are provided on the surface of the layer 12 and the side surfaces of the partition wall 13. Here, similarly to the first dielectric layer 7, the second dielectric layer 12 is formed by applying a paste-like dielectric material containing a powder of a low-melting glass material by screen printing or a die coating method and then drying. Alternatively, it is formed by a method in which a dielectric film in the form of a sheet is transferred and attached, and then fired.

  The front plate 2 and the back plate 9 are opposed to each other with the discharge space 15 interposed therebetween so that the display electrode 6 and the data electrode 11 are orthogonal to each other, and are sealed by a seal material formed on the peripheral portion. The discharge space 15 is filled with at least one rare gas of helium, neon, argon, and xenon as a discharge gas. The discharge space 15 is partitioned by the partition wall 13 and intersected by the display electrode 6 and the data electrode 11. Discharge space 15 operates as a discharge cell 16.

  Here, the characteristic point of the plasma display panel according to the embodiment of the present invention described above is that the first dielectric layer 7 and / or the second dielectric layer 12 has a multilayer structure, and The upper layer is formed so as not to cover the edge of the lower layer, that is, the upper layer is formed so as to be positioned at or inside the lower layer. Here, in order to form the first dielectric layer 7 and / or the second dielectric layer 12 into a multilayer structure, for example, a material having a high glass softening point is used for a lower layer, and a material having a low glass softening point is used for an upper layer. Accordingly, defects such as pinholes generated when the lower layer is formed are covered by the upper layer to improve the withstand voltage, or the first dielectric layer 7 and / or the second dielectric layer 12 can be It is not formed by coating, it is divided into several times, and is laminated and applied to have a predetermined thickness to improve the surface roughness, and as shown in FIG. In the cell 16 (FIG. 1), the first dielectric layer 7 has a two-layered structure of a lower layer 7a and an upper layer 7b, and the upper layer 7b has a hole, so that the first dielectric layer 7 That the layer 7 can be easily formed. It is below.

  FIG. 3 is a cross-sectional view showing a schematic configuration at an end of front plate 2 of PDP 1 according to one embodiment of the present invention. FIG. 3 shows only the front substrate 3 and the first dielectric layer 7 for simplification of the description, and shows a case of a two-layer structure. As shown in FIG. 3, the first dielectric layer 7 has a multi-layer structure in which the upper layer 7b does not cover the edge of the lower layer 7a, whereby the upper layer 27b shown in FIG. Entrapment of the air bubbles 101 as seen in the configuration covering the edge of. As a result, it is possible to suppress the occurrence of blisters, pinholes, and the like, which are considered to be caused by the bubbles contained in the first dielectric layer 7, and the occurrence of withstand voltage failure.

  Note that the above-described effects can be similarly obtained even in the case of a multilayer structure of two or more layers as long as the upper layer does not cover the lower layer, respectively. And the second dielectric layer 12 can be similarly obtained.

  Next, a method for forming the above-described first dielectric layer 7 will be described.

  As an example of a method of forming the first dielectric layer 7, a paste-like dielectric material containing a powder of a low-melting glass material, a binder resin and a solvent is applied to the front substrate 3 using a screen printing plate for the lower layer 7a. After coating on top, the lower layer 7a is formed by drying, and then, on the lower layer 7a, the upper layer 7b is applied using a screen printing plate for the upper layer 7b, and dried to form a two-layer. A method of forming a precursor of the first dielectric layer 7 having the structure may be used. Here, the screen printing plate for the upper layer 7b is smaller than the screen printing plate for the lower layer 7a, and is appropriately positioned and screen-printed to form the upper layer 7b on the lower layer 7a. The upper layer 7b does not cover the edge of 7a. Then, by firing the precursor formed as described above, the first dielectric layer 7 having a two-layer structure is formed. In addition, firing is performed by leaving the powder of the low melting point glass material contained in the dried precursor of the first dielectric layer 7 at a temperature equal to or higher than the softening point of the powder for several minutes to several tens minutes. By this baking, the precursor of the first dielectric layer 7 changes to the first dielectric layer 7. Here, the baking may be performed each time the upper layer 7b and the lower layer 7a are applied and dried, or may be performed collectively after the upper layer 7b and the lower layer 7a are applied and dried.

  Further, as another forming method, a paste-like dielectric material containing a powder of a low-melting glass material, a binder resin, a photosensitive material and a solvent is applied by a die coating method and dried to form a first dielectric material. A method of forming a precursor of the body layer 7 and thereafter firing the body layer 7 may be used. At this time, when the upper layer 7b is die-coated, it is necessary to appropriately set the application region and the positioning thereof by the die coater so as not to cover the edge of the lower layer 7a. The firing is the same as described above.

  As still another forming method, a paste-like dielectric material containing a powder of a low-melting glass material, a binder resin, a photosensitive material and a solvent is applied on a support film, and then dried to form a dielectric film. A transfer film is prepared, and a dielectric film is transferred and laminated from the transfer film to form a precursor of the first dielectric layer 7 having a multilayer structure, followed by firing. At this time, it is necessary to appropriately adjust the size of the dielectric film formed on the transfer film and the transfer position accuracy so that the layer transferred as the upper layer 7b does not cover the edge of the layer transferred as the lower layer 7a. It is. Here, when the dielectric film is transferred from the transfer film, since the dielectric film has a sheet shape, if the upper layer 7b is transferred so as to cover the edge of the lower layer 7a, the entrapment of air bubbles may occur. Since the occurrence becomes intense, a particularly large effect can be obtained by applying the present invention.

  Here, the transfer film is coated on a support film with the photosensitive paste-like dielectric material as described above using a roller coater, a blade coater, a curtain coater, and the like, and then dried, and a part or all of the solvent. , And then a cover film is provided (press-bonded) thereon. In the step of transferring the dielectric film from the transfer film to the front substrate 3, the cover film is peeled off from the transfer film, and then the transfer film is superimposed on the surface of the front substrate 3 so that the dielectric film is in contact with the surface. The film is thermocompression-bonded from above the film by a heating roller, and then the support film is peeled off. Such an operation can be performed by a laminator device. In the photolithography step, the precursor of the first dielectric layer 7 formed on the front substrate 3 is exposed to ultraviolet rays through a mask having a predetermined shape, exposed to light, and then developed. Is performed. The firing is performed by leaving the powder of the low melting glass material contained in the precursor of the first dielectric layer 7 at a temperature equal to or higher than the softening point of the powder for several minutes to several tens minutes. By this operation, the precursor of the first dielectric layer 7 changes to the first dielectric layer 7.

  Here, when the edge of the first dielectric layer 7 is covered with a sealing material as shown in FIG. 4, the edge of the first dielectric layer 7 has swollen or ruptured due to inclusion of bubbles. The presence of the portion affects the distance between the front glass substrate 3 and the rear glass substrate 10 which are arranged and sealed to face each other via a sealing material, and causes, for example, generation of crosstalk and noise (eg, noise) during image display. Sound) may occur. However, if the present invention is applied to such a configuration, the presence of a swollen or ruptured portion at the edge of the first dielectric layer 7 is suppressed, and thus the occurrence of the above-described problem is suppressed. It becomes possible.

  In the above description, the case where the first dielectric layer 7 has a two-layer structure has been described as an example. However, even in the case where the first dielectric layer 7 has a multilayer structure of two or more layers, the same method can be repeated by repeating the above-described forming method. It is possible to form.

  Further, the present invention can be similarly applied to the second dielectric layer 12 covering the data electrodes 11 of the back plate 9, and the same effect can be obtained.

  As described above, according to the present invention, it is possible to provide a plasma display panel capable of displaying an excellent image by including a dielectric layer having a multilayer structure in which inclusion of bubbles is suppressed.

Sectional perspective view showing a schematic configuration of an image display unit of a plasma display panel according to an embodiment of the present invention. Schematic sectional view showing an example of the first dielectric layer Sectional view showing a schematic configuration of a part of a front plate of a plasma display panel according to an embodiment of the present invention. Sectional view showing a schematic configuration of a part of a front plate of a plasma display panel according to an embodiment of the present invention. Sectional perspective view showing a schematic configuration of an image display unit of a conventional plasma display panel Sectional view showing a schematic configuration of a part of a front plate for explaining a problem in a conventional plasma display panel. Similarly, a cross-sectional view showing a schematic configuration of a part of a front plate for describing a problem in a conventional plasma display panel. Similarly, a cross-sectional view showing a schematic configuration of a part of a front plate for describing a problem in a conventional plasma display panel.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 Plasma display panel 4 Scanning electrode 5 Sustain electrode 6 Display electrode 7 First dielectric layer 11 Data electrode 12 Second dielectric layer

Claims (1)

In a plasma display panel having a first dielectric layer covering a display electrode composed of a scan electrode and a sustain electrode, and a second dielectric layer covering a data electrode, the first dielectric layer and / or the second dielectric layer may be A plasma display panel having a multilayer structure, wherein an upper layer does not cover an edge of a lower layer.

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