Method of forming partitions of plasma display panel and device for forming partitions

Abstract

In a method of forming partitions of a plasma display panel, the partitions of the plasma display panel are formed by using a sandblasting method, and abrasive material and partition cutting powder are dispersed in liquid after the completion of sandblasting. Further, in a device for forming partitions of a plasma display panel, the partitions of the plasma display panel are formed by a sandblasting method, and the device has a dispersing tank in which abrasive material and partition cutting powder are dispersed in liquid after the completion of sandblasting.

Description

CROSS REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2006-194771, filed on Jul. 14, 2006, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method of forming partitions of a plasma display panel in which the partitions of the plasma display panel are formed by using a sandblasting method. The present invention is also related to a device for forming the partitions of the plasma display panel.

2. Description of the Related Art

When partitions (ribs) of a plasma display panel are formed, it is conventional to use a sandblasting method. In general, a partition forming device (blasting device) for forming partitions of a plasma display panel, to which the sandblasting method is applied, is operated in such a manner that abrasive material and partition cutting powder are classified by an air current type classifier (cyclone) and the thus classified abrasive material is reused.

In this connection, International Publication Pamphlet No. 02/084689 proposes a partition forming method of forming partitions of a plasma display panel in which a sandblasting method is used. The partition forming method includes: a step for providing a sheet-like partition material which covers a display area and outside thereof on a surface of a substrate; a step for providing a mask for patterning which covers the display area and the outside thereof, so that a pattern of the display area arranged outside of the display area of the mask can be a grid-like pattern; a step for patterning the partition material covered partially with the mask by a sandblasting process; and a step for baking the partition material after the patterning.

Further, Japanese Unexamined Patent Publication (Kokai) No. 2002-127014 proposes the following technique. Processing is performed in a manner different from processing performed by a blasting device. Concerning the partitions and electrodes of a flat panel display, in order to make it possible to reuse sandblasting scraps generated in the process of sandblasting, the abrasive material is fixed to stainless steel and the abrasive material scraps are collected by means of magnetic separation from a dispersion solution in which the sandblasting scraps are dispersed in a solvent. By adding a dissolving agent for dissolving the abrasive material to the solid component in the dispersing solution, fine powder of the abrasive material, which was not collected by the magnetic separation, is dissolved and removed. In this way, the partition forming material, which is a residual of the solid component not dissolved, and/or the electrode forming material is recovered.

The prior art and its associated problem will be described in detail later with reference to relevant drawings.

SUMMARY OF THE INVENTION

An object of the present invention is to enhance a recovery efficiency of the abrasion material to be reused. Another object of the present invention is to enhance a rate of operation of a partition forming device of forming partitions of a plasma display panel. Still another object of the present invention is to easily change the abrasive material used for the partition forming device for forming partitions of the plasma display panel.

According to the present invention, there is provided a method of forming partitions of a plasma display panel in which the partitions of the plasma display panel are formed by using a sandblasting method, wherein abrasive material and partition cutting powder are dispersed in liquid after the completion of sandblasting.

Further, according to the present invention, there is provided a device for forming partitions of a plasma display panel in which the partitions of the plasma display panel are formed by a sandblasting method, comprising a dispersing tank in which abrasive material and partition cutting powder are dispersed in liquid after the completion of sandblasting.

The liquid may be organic solvent, water or water and dispersing agent. The device for forming partitions of a plasma display panel may further comprise a hydro-cyclone for classifying the abrasive material and the partition cutting powder after the completion of sandblasting, which are dispersed in liquid, by wet classification. The device for forming partitions of a plasma display panel may further comprise a continuous drying furnace for drying rough powder, which has been classified by the wet classification, so as to reuse the abrasive material.

The continuous drying furnace may dry the abrasive material to be reused so that a percentage of water contents of the dried abrasive material can not more than 5%. The dispersing tank for dispersing the abrasive material and partition cutting powder in liquid after the completion of sandblasting, the hydro-cyclone for classifying the abrasive material and partition cutting powder, which are dispersed in liquid after the completion of sandblasting, by the wet classification and a continuous drying furnace for drying the rough powder, which has been classified by the wet classification so as to reuse the abrasive material, may be arranged so that processing can be continuously performed.

The device for forming partitions of a plasma display panel may further comprise a dehydrator for dehydrating the fine powder, which has been classified by the wet classification, so as to discard the solid components and reuse the liquid.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be more clearly understood from the description of the preferred embodiments as set forth below with reference to the accompanying drawings, wherein:

FIG. 1 is a diagram schematically showing an outline of an example of a conventional plasma display panel partition forming device;

FIG. 2 is a flow chart for explaining a flow of abrasive material in the plasma display panel partition forming device shown in FIG. 1;

FIG. 3 is a diagram schematically showing an outline of an embodiment of a plasma display panel partition forming device of the present invention;

FIG. 4 is a diagram schematically showing the plasma display panel partition forming device shown in FIG. 3; and

FIG. 5 is a flow chart for explaining a flow of abrasive material in the plasma display panel partition forming device shown in FIGS. 3 and 4.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Before describing in detail the preferred embodiments of the present invention, a partition forming method, a partition formation and problems caused in the process of the partition formation of a conventional plasma display panel will be explained with reference to FIGS. 1 and 2.

FIG. 1 is a diagram schematically showing an outline of an example of a conventional plasma display panel partition forming device. FIG. 2 is a flow chart for explaining a flow of abrasive material in a plasma display panel partition forming device shown in FIG. 1.

In FIG. 1, reference numeral 1 is a working chamber, reference numeral 2 is a nozzle, reference numeral 3 is an air current type cyclone, reference numeral 4 is an abrasive material recovery tank (abrasive material recovery chamber), reference numeral 5 is an abrasive material supplying portion, reference numeral 6 is a dust collector, reference numerals 7 and 8 are respectively a foreign object removing portion and reference numeral 9 is a partition dry substrate.

As shown in FIGS. 1 and 2, first of all, in step ST1, in the working chamber 1, the abrasive material injected from the nozzle 2 polishes the partition dry substrate 9 and forms partitions (ribs), the shapes of which are predetermined, on the substrate 9 (for example, on a rear substrate of the plasma display panel).

Next, the program proceeds to step ST2. From a mixture in which the abrasive material and the partition cutting powder, which are sent from the working chamber 1, are mixed with each other, big foreign objects such as objects of dry film resist are removed by a foreign object removing portion (mesh) 7. In the foreign object removing portion (mesh) 7, the big foreign objects, which can not pass through the mesh, are periodically collected by a dust collector (not shown) and discarded.

The program further proceeds to step ST10. In step ST10, the mixture, in which the abrasive material and the partition cutting powder are mixed with each other, from which the big foreign objects have been removed by the foreign object removing portion 7, is separated into large particles and small particles by the air current type cyclone 3.

Small particles, which have been separated by the air current type cyclone 3, are collected by the dust collector 6 in step ST6. The program further proceeds to step ST7, and the partition cutting powder and the abrasive material are discarded.

On the other hand, the large particles, which have been separated by the air current type cyclone 3, are supplied to the abrasive material recovery tank 4 in step ST3. The program further proceeds to step ST4, and the large particles are returned to the abrasive material supplying portion 5 and reused as abrasive material. New abrasive material is replenished to the abrasive material supplying portion 5 from the outside.

In step ST5, from the abrasive material sent from the abrasive material supplying portion 5, foreign objects are removed by the foreign object removing portion 8. After that, the program is returned to step ST1 and the abrasive material is injected from the nozzle 2 in the working chamber 1, so that partitions of a predetermined shape can be formed on the substrate.

In this connection, in step ST8, the foreign objects, which have been removed by the foreign object removing portion 8, are periodically collected by a dust collector and discarded as the abrasive material which can not be reused.

As explained before referring to FIGS. 1 and 2, in the conventional plasma display panel partition forming device (method), the abrasive material is reused when large particles and small particles are separated from each other (step ST10) by the air current type cyclone 3.

However, in this air current type classifier, particles can not be sufficiently dispersed. Therefore, the partition cutting powder or the abrasive material and partition cutting powder are coagulated and the partition cutting powder is mixed into the abrasive material which has already been classified. Accordingly, there is a possibility that the sampler rate is lowered and the partitions are damaged. Therefore, in the conventional plasma display panel partition forming device (blasting device), for example, a no-load running test is periodically performed, that is, a no-load running test is performed each time a predetermined number of works are processed so as to prevent an increase in the partition cutting powder. Therefore, an operation rate of the device is lowered.

Further, for example, when a cutting point is changed in order to suppress an increase in the partition cutting powder, a recovery rate of the abrasive material is lowered. Further, in order to perform sandblasting on a highly fine panel which has been recently produced, it is indispensable to reduce a particle size of the abrasive material. However, for the reasons described above, it is not easy to change the abrasive material.

Referring to the accompanying drawings, an embodiment of the method of forming partitions of a plasma display panel of the present invention will be described in detail below. Further, an embodiment of the device for forming the partitions of the plasma display panel of the present invention will be described in detail below.

FIG. 3 is a diagram schematically showing an outline of an embodiment of a plasma display panel partition forming device of the present invention. FIG. 4 is a diagram schematically showing the plasma display panel partition forming device shown in FIG. 3. FIG. 5 is a flow chart for explaining a flow of abrasive material in the plasma display panel partition forming device shown in FIGS. 3 and 4.

In FIG. 3, reference numeral 1 is a working chamber, reference numeral 2 is a nozzle, reference numeral 3 is an air current type cyclone, reference numeral 4 is an abrasive material recovery tank (abrasive material recovery chamber), reference numeral 5 is an abrasive material supplying portion, reference numeral 6 is a dust collector, reference numerals 7 and 8 are respectively a foreign object removing portion and reference numeral 9 is a partition dry substrate. Further, reference numeral 10 is a dispersion tank, reference numeral 11 is a motor, reference numeral 12 is a liquid feed pump, reference numeral 13 is a hydro-cyclone, reference numeral 14 is a continuous drying furnace and reference numeral 15 is a centrifugal dehydrator. In this connection, like reference numerals are used to indicate like components in FIGS. 1 and 2 indicating an example of a prior art, and FIGS. 3 to 5 indicating an embodiment of the present invention.

As shown in FIGS. 3 to 5, first of all, in step ST1, in the working chamber 1, the abrasive material, which has been injected from the nozzle 2, polishes the partition dry substrate 9. Therefore, partitions of a predetermined shape are formed on the substrate.

Next, the program proceeds to step ST2. Big foreign objects such as dry film resist are removed from a mixture of the abrasive material and the partition cutting powder, which were sent from the working chamber 1, by the foreign object removing portion 7. In this case, in the foreign object removing portion 7, the big foreign objects, which can not pass through the mesh, are periodically collected by a dust collector (not shown) and discarded.

Then, the program proceeds to step ST10. The mixture of the abrasive material and the partition cutting powder, from which the big foreign objects have been removed by the foreign object removing portion 7, is separated into large and small particles by the air current type cyclone 3.

Small particles, which have been separated by the air current type cyclone 3, are collected by the dust collector (6) in step ST6. The program further proceeds to step ST7. The partition cutting powder and the abrasive material are discarded. In this case, no solid contents exist in the small particles separated by the air current type cyclone 3.

On the other hand, large particles separated by the air current type cyclone 3 are dispersed in the liquid in the dispersion tank 10 in step ST21. In this case, the specific gravity of the abrasive material and the partition cutting powder is relatively high. Therefore, the abrasive material and the partition cutting powder are always agitated by agitator blades 16 driven by the motor 11. In this connection, the agitator includes: a dispersing tank 10; a motor 11; and agitating blades 16. Examples of the liquid in the dispersing tank 10 are an organic solvent such as ethanol, water, and water and a dispersing agent.

A mixed solution, in which large particles are agitated in the dispersing tank 10, is supplied to the hydro-cyclone 13 by the liquid feed pump 12 and subjected to wet classification in step ST22.

Rough powder, which has been classified by the wet classification by the hydro-cyclone 13, is dried by the continuous drying furnace 14. Then, the program proceeds to step ST3 and the rough powder is supplied to the abrasive material recovery tank 4. The program further proceeds to step ST4 and the rough powder is returned to the abrasive material supplying portion 5 and reused as the abrasive material. In this case, new abrasive material is replenished to the abrasive material supplying portion 5 from the outside.

In step ST5, from the abrasive material sent from the abrasive material supplying portion 5, foreign objects are removed by the foreign object removing portion 8. After that, the program is returned to step ST1 and the abrasive material is injected from the nozzle 2 in the working chamber 1 so that partitions of a predetermined shape can be formed on the substrate.

In this connection, the foreign objects removed by the foreign object removing portion 8 are periodically collected by a dust collector in step ST8 and then discarded as the abrasive material, which can not be reused, in step ST9.

Fine powder, which has been classified by the wet classification by the hydro-cyclone 13, is separated into the liquid and the solid components (partition cutting powder) by the centrifugal dehydrator 15 in step 24. Then, the liquid is returned to the dispersing tank 10 and the solid components are discarded.

In the present embodiment, a series of processing is continuously performed. In this case, a series of processing includes: processing in which the abrasive material and the partition cutting powder after a process of sandblasting are dispersed in liquid; processing in which the abrasive material and the partition cutting powder after a process of sandblasting, which are dispersed in liquid, are subjected to wet classification; and processing in which rough powder, which has been classified by wet classification, is dried in a continuous drying furnace so that the abrasive material can be reused. Due to the foregoing, dispersion and classification of the abrasive material and the partition cutting powder can be subjected to in-line processing with high accuracy. Further, it is possible to enhance a recovery efficiency of the abrasion material. It is also possible to enhance an operation rate of the device.

In the embodiment described above, large particles, which have been separated by the air current type cyclone 3, are dispersed and agitated in the liquid in the dispersing tank 10 and classified by the wet classification by the hydro-cyclone 13. However, the characteristic of the present invention is to disperse the abrasive material and the partition cutting powder after the completion of sandblasting. Therefore, for example, the air current type cyclone 3 may not be necessarily provided.

As described above in detail, according to the present invention, when the wet type classifier (hydro-cyclone) is used, it is possible to enhance the degree of dispersion of the partition cutting powder and the abrasive material. Further, the dispersion can be also enhanced by a shearing force generated by the hydro-cyclone. Therefore, the classification accuracy can be more enhanced. Further, the abrasive material used for the plasma display panel partition forming device can be easily changed.

The present invention can be widely applied to a plasma display panel partition forming device in which partitions of various shapes of the plasma display panel are formed by the method of sandblasting.

Many different embodiments of the present invention may be constructed without departing from the scope of the present invention, and it should be understood that the present invention is not limited to the specific embodiments described in this specification, except as defined in the appended claims.

Claims

1. A method of forming partitions of a plasma display panel in which the partitions of said plasma display panel are formed by using a sandblasting method, wherein abrasive material and partition cutting powder are dispersed in liquid after the completion of sandblasting.

2. The method of forming partitions of a plasma display panel as claimed in claim 1, wherein the liquid is organic solvent, water or water and dispersing agent.

3. The method of forming partitions of a plasma display panel as claimed in claim 1, wherein abrasive material and partition cutting powder are dispersed in liquid after the completion of sandblasting and classified by wet classification.

4. The method of forming partitions of a plasma display panel as claimed in claim 3, wherein rough powder, which has been classified by the wet classification, is dried in a continuous drying furnace and reused as abrasive material.

5. The method of forming partitions of a plasma display panel as claimed in claim 4, wherein a percentage of water contents of the dried abrasive material is not more than 5%.

6. The method of forming partitions of a plasma display panel as claimed in claim 4, wherein processing in which the abrasive material and the partition cutting powder after a process of sandblasting are dispersed in liquid, processing in which the abrasive material and the partition cutting powder after a process of sandblasting are subjected to wet classification and processing in which rough powder, which has been classified by wet classification, is dried in a continuous drying furnace so that the abrasive material can be reused are continuously performed.

7. The method of forming partitions of a plasma display panel as claimed in claim 3, wherein the fine powder, which has been classified by the wet classification, is dehydrated and solid contents are discarded and the liquid is reused.

8. A device for forming partitions of a plasma display panel in which the partitions of said plasma display panel are formed by a sandblasting method, comprising:

a dispersing tank in which abrasive material and partition cutting powder are dispersed in liquid after the completion of sandblasting.

9. The device for forming partitions of a plasma display panel as claimed in claim 8, wherein the liquid is organic solvent, water or water and dispersing agent.

10. The device for forming partitions of a plasma display panel as claimed in claim 8, further comprising:

a hydro-cyclone for classifying the abrasive material and the partition cutting powder after the completion of sandblasting, which are dispersed in liquid, by wet classification.

11. The device for forming partitions of a plasma display panel as claimed in claim 10, further comprising:

a continuous drying furnace for drying rough powder, which has been classified by the wet classification, so as to reuse the abrasive material.

12. The device for forming partitions of a plasma display panel as claimed in claim 11, wherein the continuous drying furnace dries the abrasive material to be reused so that a percentage of water contents of the dried abrasive material can not more than 5%.

13. The device for forming partitions of a plasma display panel as claimed in claim 11, wherein said dispersing tank for dispersing the abrasive material and partition cutting powder in liquid after the completion of sandblasting, said hydro-cyclone for classifying the abrasive material and partition cutting powder, which are dispersed in liquid after the completion of sandblasting, by the wet classification and a continuous drying furnace for drying the rough powder, which has been classified by the wet classification so as to reuse the abrasive material, are arranged so that processing can be continuously performed.

14. The device for forming partitions of a plasma display panel as claimed in claim 10, further comprising:

a dehydrator for dehydrating the fine powder, which has been classified by the wet classification, so as to discard the solid components and reuse the liquid.