This application claims the benefit of Korean Patent Application No. 10-2005-0061741, filed on Jul. 08, 2005, Korean Patent Application No. 10-2005-0082618, filed on Sep. 06, 2005, Korean Patent Application No. 10-2005-0106134, filed on Nov. 07, 2005, which is hereby incorporated by reference as if fully set forth herein.
1. Field of the Invention
The present invention relates to a plasma display panel, and more particularly, to a plasma display panel, in which a process for forming black tops on a lower plate is simplified, and a method for manufacturing the same.
2. Discussion of the Related Art
Generally, in a plasma display panel, discharge cells are divided from each other by barrier ribs formed between a front substrate and a rear substrate. Each of the discharge cells is filled with a main discharge gas, such as neon gas, helium gas, or neon-helium mixed gas, and an inactive gas containing a small amount of xenon. When an electric discharge occurs by means of a high-frequency voltage, the inactive gas generates vacuum ultraviolet rays, and the vacuum ultraviolet rays cause fluorescent materials between the barrier ribs to emit light, thereby forming an image. The above-described plasma display panel has a small thickness and a light weight, thus being spotlighted as the next generation display device.
Barrier ribs 112 formed in a stripe type (or a well type) for forming a plurality of discharge spaces, i.e., discharge cells, are arranged in parallel on the rear substrate 110. Further, a plurality of the address electrodes 113 for performing address discharge to generate vacuum ultraviolet rays are arranged in parallel with the barrier ribs 112. R, G, B fluorescent materials 114 for emitting visible rays to display an image when the address discharge occurs are applied to the upper surface of the rear substrate 110. A lower dielectric layer 115 for protecting the address electrodes 113 is formed between the address electrodes 113 and R, G, B fluorescent materials 114.
The above conventional plasma display panel is manufactured through a glass-manufacturing process, a front substrate-manufacturing process, a rear substrate-manufacturing process, and an assembling process.
First, the front substrate-manufacturing process includes forming scan electrodes and sustain electrodes on a front glass, forming an upper dielectric layer for limiting discharge current of the scan and sustain electrodes and insulating pairs of the scan and sustain electrodes from each other, and forming a protection layer on the upper dielectric by depositing magnesium oxide for facilitating the discharge condition
The rear substrate-manufacturing process includes forming address electrodes on a rear glass, forming a lower dielectric layer for protecting the address electrodes, forming barrier ribs on the upper surface of the lower dielectric layer for dividing discharge cells from each other, and forming a fluorescent material layer on regions between the barrier ribs for emitting visible rays.
The above method for manufacturing the plasma display panel has problems, as follows.
The barrier ribs serve to prevent electrical and optical crosstalk between the discharge cells, and are important to increase the display quality and the light-emitting efficiency of the plasma display panel. As the PDPs are developed towards large-size and high-definition trends, various researches on the barrier ribs have now been made.
First, a barrier rib material is formed on the lower dielectric layer by printing a barrier rib paste or laminating a barrier rib green sheet on the lower dielectric layer, and the barrier ribs are obtained by a sanding, etching, or photosensitive method. Here, in order to increase the contrast of the PDP, the formation of a black top on the upper surfaces of the barrier ribs is added to this barrier rib-forming process. That is, a black top material and a dry film resist (DFR) layer are sequentially formed on the barrier rib material on the lower dielectric layer. Then, after the barrier ribs and black tops are formed by a sanding method, the DFR layer is removed.
Since the barrier rib material, the black top material, and the DFR layer are sequentially formed on the lower dielectric layer, the above conventional barrier rib-forming process additionally requires separate materials and steps. Further, since the width of the pattern of the black tops cannot be adjusted, the luminance of the plasma display panel is deteriorated. Moreover, the side surfaces of the black tops are exposed to an etchant during the exposing and developing processes.
Accordingly, the present invention is directed to a black top green sheet, a plasma display panel, and a method for manufacturing the same.
One object of the present invention is to provide a plasma display panel, in which a process for forming barrier ribs and black tops is simplified, and a method for manufacturing the same.
To achieve this object and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a method for manufacturing a plasma display panel includes forming a barrier rib material on a lower plate, on which address electrodes and a dielectric are provided; forming a black top material comprising a photosensitive substance on the barrier rib material; patterning the black top material to form black tops; and patterning the barrier rib material using the black tops as a mask to form barrier ribs.
In a further aspect of the present invention, a plasma display panel includes upper and lower plates, which face each other; barrier ribs formed on the lower plate and comprising a white material; and black tops formed on the barrier ribs and having a narrower width than that of the barrier ribs.
In another aspect of the present invention, a black top green sheet includes a photosensitive black paste layer, which has viscosity when it is not exposed to light, and loses the viscosity when it is exposed to the light; and first and second protection films provided on the upper and lower surfaces of the black paste layer.
In another aspect of the present invention, a method for manufacturing a plasma display panel includes preparing a black top green sheet, the viscosity of which is changed when it is exposed to light; selectively exposing the black top green sheet to light according to regions corresponding to barrier ribs; and bonding non-exposed portions of the black top green sheet to the barrier ribs provided on a lower plate.
In another aspect of the present invention, a plasma display panel includes upper and lower plates, which face each other; and black tops formed on barrier ribs in the lower plate, and comprising a photosensitive substance, which maintains viscosity when it is not exposed to light, and loses the viscosity when it is exposed to the light.
In another aspect of the present invention, a method for manufacturing a plasma display panel includes forming a barrier rib material on a lower plate, on which address electrodes and a dielectric are provided; forming a black top material comprising a photosensitive substance on the barrier rib material; and forming barrier ribs and black tops by exposing the barrier rib material and the black top material to light and developing the barrier rib material and the black top material.
In yet another aspect of the present invention, a method for manufacturing a plasma display panel includes forming a multi-layer green sheet comprising a photosensitive substance on a lower plate, on which address electrodes and a dielectric are provided; and forming barrier ribs and black tops by exposing the multi-layer green sheet to light and developing the multi-layer green sheet.
It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:
Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
First, as shown in
Thereafter, as shown in
Thereafter, as shown in
Thereafter, as shown in
Thereafter, as shown in
As shown in
The plasma display panel manufactured by the above method has the black tops formed on the white barrier ribs, and thus has an improved contrast. As described above, the width of the black tops is adjusted, thereby preventing the deterioration of the luminance of the plasma display panel. The plasma display panel has the black tops including the photosensitive substance formed on the barrier ribs and does not require a DFR layer, thus preventing the addition of steps of the manufacturing process. Further, since the fluorescent materials and the black tops are simultaneously baked, it is possible to simultaneously achieve the removal of organic matters and the adjustment of the width of the black tops.
The black top green sheet of the present invention comprises a black paste layer 300, and first and second films 310 and 320 provided at both surfaces of the black paste layer 300. The black paste layer 300 is made of a black-colored material having a light absorbing property, the viscosity of which is changed by ultraviolet rays irradiated thereonto. That is, the black paste layer 300 preferably includes a photosensitive material, which has the viscosity with the first and second films 310 and 320, and is hardened by ultraviolet rays irradiated thereonto and loses the viscosity. More preferably, the black paste layer 300 further includes a black inorganic pigment, an organic binder made of an organic matter, and a solvent.
The above photosensitive material is a photosensitive polymer, which includes a polymer and a photosensitizer. Since the photosensitive material has a negative property, the bonding force of the photosensitive is increased when it is exposed to light.
The first and second films 310 and 320 are formed on the upper and lower surfaces of the black paste layer 300, and serve as protection films. In order to perform an exposing process, which will be described later, preferably, at least one of the first and second films 310 and 320 is transparent. Further, in order to easily attach and remove the first and second films 310 and 320 to and from the black paste layer 300, preferably, the first and second films 310 and 320 have surface characteristics, which reduce the viscosity of the black paste layer 300.
The above black top green sheet serves as not only a material for forming black tops on the surface of barrier ribs, but also a black matrix. Further, the black top green sheet may serve various purposes for forming a black pattern layer. Preferably, the black top green sheet is first patterned and then formed on the surface of structures, such as barrier ribs, rather than is first formed directly on the upper surface of the structures and then patterned. That is, although structures, such as the black tops, to which a black material layer is applied, are complicated and the thickness of the layer is limited so that the layer cannot be formed by a printing method, the black top green sheet is used to easily form the black material layer having a small thickness. Particularly, in case that a layer to be formed has a fine thickness or cannot be patterned by etching, the black top green sheet is useful.
First, the black top green sheet, as shown in
Thereafter, as shown in
Thereafter, as shown in
Thereafter, as shown in
In the above method of this embodiment, in order to improve the white ray reflecting property of the barrier ribs and the improvement of the contrast due to the black tops formed on the upper surfaces of the barrier ribs, the black tops preferably have a thickness of below 30% of that of the barrier ribs.
Processes for forming other parts except for the process for forming the barrier ribs and the black tops in the method of this embodiment are the same as those in the conventional method. Accordingly, it is possible to easily separate the exposed portions of the black paste layer from the lower plate, while increasing the viscosity of the non-exposed portions of the black paste layer with the barrier ribs. Further, since the black paste layer is selectively exposed to light according to the pattern of the barrier ribs, and is then transcribed onto the barrier ribs, it is possible to adjust the thickness of the black paste layer. Moreover, the barrier ribs are not exposed to an etchant for a long period of time, thus not being distorted.
First, as shown in
Thereafter, as shown in
Thereafter, as shown in
Thereafter, the barrier ribs 570 and the black tops 580, as shown in
First, as shown in
Thereafter, as shown in
Thereafter, the multi-layer green sheet 650 is exposed to light, and is developed, thus forming barrier ribs and black tops. Preferably, the multi-layer green sheet 650 is selectively exposed to the light using a mask in the same manner as the method of the third embodiment.
Thereafter, as shown in
In accordance with the third and fourth embodiments, the black tops and the barrier ribs are simultaneously formed without the formation of the conventional DFR layer, thus reducing production costs of the plasma display panel and shortening the manufacturing process of the plasma display panel.
The plasma display panel manufactured by the above method uses barrier ribs and a black top material including a photosensitive substance, thus simplifying a process for manufacturing the plasma display panel and reducing the production costs of the plasma display panel. Although the barrier ribs are made of a white material, the black tops, which are formed on the barrier ribs, reduce the reflectance of external light, thus maximizing the contrast of the plasma display panel.
Further, the above method may be applied to other display panels, such as an OLED and an LCD, as well as a plasma display panel.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
Number | Date | Country | Kind |
---|---|---|---|
10-2005-0061741 | Jul 2005 | KR | national |
10-2005-0082618 | Sep 2005 | KR | national |
10-2005-0106134 | Nov 2005 | KR | national |