JP2000056472A - Developing method, production of member for plasma display and developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prolong the life of a developer by removing a developing residue and to realize a developing process having a small proportion defective by removing the residue of the developer from the developer by a centrifugal separation mechanism. SOLUTION: The system of a centrifugal separation mechanism is not limited particularly but it is desirable to adopt a decanter system because continuous processing for removing a residue can be performed thereby. The decanter system is ordinarily constituted of elements such as a bowl part 1, a screw conveyor 3 continuously discharging the residue 2, a motor 4 for rotating them and a speed reducer 5 giving a relatively differential speed to the bowl part 1 and the conveyor 3. Then, when a developer 7 including the residue 2 is inserted in the bowl part 1 rotating at a high speed from a feed pipe 6, the residue 2 is deposited on the outer periphery of the bowl part 1 by a centrifugal effect being >=2000G. The residue 2 is fed out by the conveyor 3 to which the differential speed is given and only the drained residue 2 is taken out and separated from the clarified developer 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for recycling a developer of a developing device used for a developing operation and a technique for recovering raw materials.

[0002]

2. Description of the Related Art Plasma display panels (PDPs)
Since they can display at a higher speed and can be easily made larger in size than liquid crystal panels, they have permeated fields such as OA equipment and publication display devices. Further, progress in the field of high-definition television is highly expected.

[0003] With the expansion of such applications, attention has been paid to color PDPs which are fine and have a large number of display cells. The PDP generates a plasma discharge between electrodes facing each other in a discharge space formed between a front glass substrate and a rear glass substrate, and irradiates ultraviolet rays generated from a sealed gas to phosphors in the discharge space. The display is performed by doing so.

The formation of a color PDP requires many steps of forming electrodes, partitions, dielectrics, and phosphors even if only a back plate is formed. Above all, the steps of forming electrodes, partitions, and phosphors having a complicated pattern are carried out by any method. Attempted.

Typical manufacturing methods include screen printing, thin film etching, lift-off, and photosensitive methods for electrodes, screen printing, photosensitive, lift-off, and sand blast methods for partition walls, and screen printing for phosphors. And photosensitive methods.

[0006] Of the above manufacturing methods, all methods except the screen printing method have a photo process in the process.
It can be seen that photo processes are often used for PDPs.

The principle of the photo process is as follows. By irradiating a coating film and a film having a photo-insolubilized or photo-solubilized type photosensitive component with light through a photomask having a desired pattern, a difference in molecular weight is selectively generated, and a desired molecular weight is obtained. This causes a difference in solubility in a liquid (hereinafter referred to as a developer). By immersing or spraying this in a liquid, the dissolved component is dissolved in the liquid to form a desired pattern.

Although the photosensitive components are eluted by this operation, not all of them are completely dissolved. In the case of, for example, a photosensitive paste which is a mixture of inorganic components and photosensitive components, the inorganic components are not completely dissolved. Since it does not dissolve in the liquid, it remains as a mixture in the liquid. These are referred to as development residues, and if the amount is large, it may cause a failure of the circulation line in the apparatus or may contaminate the developed product.

In the PDP, a display having a maximum diagonal of 60 inches is formed, and development of a large substrate is required. Furthermore, for example, when forming a rib by a photosensitive method, a coating film of 100 to 200 μm is formed, so that a large amount of development residue is mixed into the developer every time one sheet is formed.
In addition, since an expensive metal such as silver is used for forming the electrodes, a technique for collecting development residues is desired for cost reduction.

Usually, the developing solution is used repeatedly, and when the concentration exceeds the usage limit, the entire amount is exchanged or a certain amount of the solution is taken out together with the developing residue mixed in the solution, and then a certain amount of a new solution is added to reduce the concentration. The method of returning to the set concentration and using it is adopted. However, in PDP,
This method requires frequent replacement, and has a problem that a large amount of waste liquid is generated. Further, when the amount of the residue in the developing solution increases, the developing residue tends to remain on the product, and there is a problem that the defective rate increases.

As the development residue removal technique, there are known a method of providing a filter in a developer circulation line, a method of removing with a pantyhose mesh, and a method of providing a sedimentation tank and returning only the supernatant to a developer tank. However, the filter method has problems that the frequency of replacement is high, the device is stopped at the time of replacement, the problem that the pantyhose mesh cannot be removed coarsely, and the sedimentation tank requires a large area to reduce the flow rate. .

[0012]

SUMMARY OF THE INVENTION It is an object of the present invention to remove a developing residue and to realize a developing step with a small defective rate.

[0013]

According to the present invention, there is provided a developing method for forming a pattern by immersing or / and jetting a liquid into a liquid to remove an eluted component. This is achieved by a developing method characterized by removal.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Centrifugal separation is a method of mechanically separating a residue from a developer by centrifugal force by utilizing a specific gravity difference between a residue such as a solid content existing in a liquid and a developer. .
The specific gravity difference depends on the particle size, but the residue-liquid specific gravity / liquid specific gravity is 0.2.
Above, separation can be achieved, and separation of two or more non-solvated systems is possible. By utilizing this, separation of oil and water and separation of solid / liquid can be performed.

Since the centrifugal separation is performed mechanically, there is no need to add a polymer flocculant to the liquid and enlarge the particles as in the method using a filter or filter paper to separate the particles. There is no chemical solution in the developer. for that reason,
There is no secondary influence on the developing operation. Further, since the specific gravity difference is used, even a residue having a wide particle size distribution can be easily separated. Further, the cost can be reduced by using the development residue again as a raw material for the formation step. In particular, when an expensive metal is generated as a residue, specifically, when a noble metal such as gold or silver is used in a material, the residue is recovered, re-melted, and used again as a raw material, thereby greatly reducing costs.

The present invention can be used in any process including a developing process. Specifically, a PDP having a development process
It is preferable to use the method for manufacturing a member for production because it is advantageous in terms of yield improvement and cost reduction. In particular, it is more preferably used for forming electrodes on the front plate and forming electrodes, partition walls, and phosphor layers on the back plate. Specific methods for producing these members include a photosensitive method, a sand blast method, a lift-off method, and a thin film etching method. Occurs. For this reason, centrifugation is particularly effectively employed.

Among the forming steps, it is preferable to use it in the electrode forming step. A conductive metal such as silver used for forming an electrode has a large specific gravity, so that solid-liquid separation by centrifugation is easy and can be separated efficiently. For example, frequently used silver has a specific gravity of about 10. In addition, the cost can be reduced by collecting, remelting and recycling expensive components such as silver.

Also, it is preferable to use it in the rib forming step. For example, in the photosensitive method, the photosensitive paste is 200 μm
Apply to nearby thick film. For a 60-inch diagonal substrate, about 400 g of paste is applied per sheet when forming ribs. When this is a negative type, about 80% is eluted by development and about 300 g of paste is mixed into the developer. By removing this constantly by centrifugation, a clarified developer can be used, and the defective rate due to residues can be reduced. Similarly to silver, the recovered glass can be re-melted and reused.

It is also preferable to use it for forming a phosphor layer. Phosphors are expensive at tens of thousands of yen per kg. When a phosphor is formed by a photosensitive method, a phosphor paste for one color is solid printed on the entire surface, dried, exposed, and developed to form one color. In other words, two-thirds of the total area initially applied to form one color is lost by development, which causes a cost increase. Centrifugation allows for cost reduction by collecting and recycling this.

It is also preferable to use the black matrix or black stripe formed for improving the contrast, and the color filter formed for improving the color purity. Formation and the like. In the case of black matrix or black matrix formation, the defective rate can be reduced by using a clear developer, and in the case of color filter formation, the yield can be reduced in that the defective rate can be reduced, such as color mixing due to residues, and the phosphor can be recovered. This is preferable in terms of cost reduction.

The centrifugal separation mechanism is not particularly limited, but is preferably a decanter type because continuous processing of residue removal is possible.

In the decanter system, as shown in FIG. 1, a bowl portion 1, a screw conveyor 3 for continuously discharging the residue 2, a motor 4 for rotating these components, and a relative speed difference between the bowl portion 1 and the screw conveyor 3 are provided. It is composed of elements of the speed reducer 5.

When the developer 7 containing the residue 2 is inserted from the feed pipe 6 into the bowl portion 1 rotating at a high speed,
Due to the centrifugal effect of 2000G or more, the residue 2 is in the bowl 1
Settles on the outer periphery. The residue 2 is sent out by a screw conveyor 3 provided with a differential speed, and only the drained residue 2 is taken out and separated from the clarified developer 8. Both the residue 2 and the clarified developer 8 are continuously discharged, which is a very useful method for producing a large amount of solids in a short time.

It is preferable that the inside of the separator is subjected to abrasion resistance processing. In the production of PDP members, for example, in the case of the photosensitive method, the solid content in the developer is conductive metal, glass,
Since the phosphor is a substance having relatively high hardness, the inside of the device may be worn. By applying abrasion treatment,
The metal constituting the separator is not mixed into the liquid, so that defects such as coloring during firing can be prevented. More preferably, the tip of the screw conveyor 3, which is most susceptible to abrasion, is preferably subjected to abrasion resistance. Specific methods of wear resistance treatment include tungsten carbide (WC), Hastelloy B &
WC, Hastelloy C-276, Stellite # 1, Stellite 1016, Eutaloy, Rokide C, alumina,
It is preferable to perform abrasion resistance processing by spraying Meteco # 101 or the like, or by sticking it as a chip.

A separating plate (vane) 9 is provided in a separating area in the decanter.
It is also preferable to provide a fine particle because it is possible to remove even fine particles. By having the separating plate 9 as shown in FIG.
Since the solids fall down in the outer circumferential direction of the rotating body while sliding on the surface of the separation plate 9, not only the separation is promoted, but also fine particles which can easily fly up in the liquid can be removed. The material of the separation plate 9 is plastic, SUS306, SUS31.
A stainless steel material such as No. 4 is generally used, but a stainless steel material subjected to a wear resistance treatment may be used. However, if it is too heavy, it will be inconvenient to rotate it, so it is better to select the material in consideration of that point.

Clarified developer 8 separated by centrifuge
Is also preferably passed through a filter to remove fine particles, because the residue removal rate in the liquid can be further improved. The mesh of the filter is preferably 1 μm or less, more preferably 0.5 μm or less.

The residue removing unit 10 for removing the residue from the developer is connected to the tank unit 12 for stirring and controlling the temperature of the developer in parallel with the developing unit 11, so that the residue removing process is repeatedly performed. Is preferred. Tank part 1
2, the developer is removed, and after removing the residue, the clarified developer is returned to the tank unit 12. This makes it possible to arbitrarily adjust the flow rate flowing to the residue removal processing unit 10 and to optimize the residue removal. Processing conditions can be selected. Further, by providing an outlet for the developer leading to the residue removal processing unit 10 upstream of the return port, the clarified developer can be efficiently supplied to the tank unit 12. As shown in FIG. 3, after the development is completed, the developer containing the residue is immediately passed to the residue removal processing section 10 and the developer subjected to the residue removal processing is caused to flow near the supply port to the development section 11 so as to achieve more clear development. The liquid can be used effectively.

More preferably, the tank section 12 is preferably partitioned into at least two places to form a cascade structure. More preferably, the height of the partition plate 13 is increased toward the upstream side so that the liquid in each room is not mixed. As shown in FIG. 4, the tank is divided into several places, and a liquid supply port to the developing unit 11 and the developing unit 1 are provided at both ends of the tank.
By providing a liquid return from one, the flow of liquid is restricted. By providing a supply port to the residue removal processing unit 10 on the return port side and an outlet from the processing unit on the supply port side, it is possible to separate the developer before processing from the clarified developer, and to efficiently develop clarified developer. Liquids can be used.

It is preferable that the concentration of the developer is periodically corrected. As the concentration measuring device, there are a PH meter, an electric conductivity meter, an automatic titrator, and the like, but any device may be selected as long as it can select a concentration that is optimal for the developing system. It is preferable that the density is controlled by these density measuring devices, and after the density falls below a certain density value, the density is corrected by adding a new solution whose concentration has been adjusted or a considerable amount of a stock solution of a developing solution.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to embodiments. However, the present invention is not limited to this. The concentrations in the examples are% by weight unless otherwise noted.

Embodiment 1 The developing device is composed of a developing unit 11, a tank unit 12, and a residue removal processing unit 10.

The developing unit 11 is attached to one shower tube, and nozzles are installed downward at a pitch of 150 mm. The developer moves below the developer at a constant speed, and after the developer is sprayed from the nozzle onto the developer, it is collected and collected in the tank unit 12.
Has been led to.

The tank 12 has a capacity of 300 L and is divided into three rooms by a partition plate 13. The capacities are 50 L, 70 L, and 180 L in this order. The developing solution is guided from the developing unit 11 to the 50 L tank,
It has a cascade structure in which a tank and a 180L tank flow in this order. The developer always uses an automatic titrator (Electrochemical Systems 1)
036D), and monoethanolamine, which is a stock solution of a developer, is injected at a set lower limit, and adjusted to a set value concentration (a 0.2% by weight aqueous solution of monoethanolamine). A line is drawn from the 50 L tank to the residue removal processing section.
It is returned to L tank. In the 180 L tank, the temperature of the developer is controlled while stirring the developer, and the temperature is adjusted by a heater.

The residue removing section 10 was used by connecting a decanter type centrifugal separator and a filter having a filter diameter of 0.5 μm in series. As the flow of the liquid, the liquid was introduced from the tank section 50L by a pump, and the clarified developer 8 was passed through a filter, and then returned to the 180L tank.

The centrifugal separator is a separation plate 9 as shown in FIG.
Was used. Although the main constituent material is SUS304, the tip of the screw conveyor 3 where wear is severe is subjected to a wear-resistant treatment in which a WC chip is attached. In the test stage, it was confirmed that the developer after the residue removal processing was free from metal component contamination. Using this apparatus, a 200-μm-high partition wall before firing was formed on a 60-inch substrate by a photosensitive paste method. By development, 300 g of paste was mixed as a residue into the developer per sheet, and this was developed into 200 sheets in 2 minutes of tact.

When the residue was removed at a rate of 5 L / min, the solid concentration in the developer was always constant at 5%, and the defective rate of the product was 0%. Further, when the water content of the separated solid content was completely evaporated, 57 kg of solid matter could be collected.

Example 2 The same operation as in Example 2 was performed except that the filter was removed from the residue removal processing section 10. The solid content in the developing solution was constant at 7%, and the defective rate of the product was 0%. Met. Further, when the water content of the separated solid content was completely evaporated, 5
6 kg of solids could be collected.

Example 3 The same operation as in Example 3 was carried out except that the filter was removed using a centrifuge in which the separator 9 was removed as shown in FIG. %, And the defect rate of the product was 0%. Further, when the water content of the separated solid content was completely evaporated, 50 kg of a solid substance could be collected.

Example 4 A silver electrode was formed by a photosensitive method, and the thickness before firing was 10 μm.
The same operation as in Example 1 was performed except that m was used. By development, 120 g of residue per sheet is mixed into the developer. After developing 200 sheets in 2 minutes of tact and removing the residue, the solid concentration of the developing solution was constant at 3%, and the defective rate of the product was 0%. Further, when the water content of the separated solid content was completely evaporated, 23 kg of solid matter could be collected.

Example 5 The same operation as in the example was performed except that a phosphor was formed by a photosensitive method and the thickness was set to 20 μm. In the case of red, the residue per sheet was 50 g. This is 2 minutes in 2 minutes
After developing 00 sheets and removing the residue, the solid content concentration of the developing solution was constant at 4%, and the product defect rate was 1%.
When the water content of the separated solid was completely evaporated,
10 kg of solids could be collected.

When the same operation was performed for green and blue, solids of a total of 30 kg for the three colors could be removed.

Comparative Example 1 The same operation as in Example 1 was carried out except for the residue removal processing section 10. As a result, clogging occurred in the liquid feed line to the developing section 11, and the operation was interrupted. .

Comparative Example 2 The same operation as in Example 1 was performed, except that a filter was used in the residue removing section 10. Work was stopped due to clogging immediately.

[0044]

According to the present invention, the product defect rate can be improved, and the yield can be improved. Further, the life of the developing solution can be prolonged, and expensive materials such as silver can be recovered and reused, so that the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a simple sectional view showing an example of a centrifugal separator of the present invention.

FIG. 2 is a simple schematic diagram showing an example of the centrifugal separator of the present invention.

FIG. 3 is a simple schematic diagram showing an example of a tank section of the present invention.

FIG. 4 is a schematic view showing an example of a tank section according to the present invention.

[Explanation of symbols]

 1: Bowl section 2: Residue 3: Screw conveyor 4: Motor 5: Reducer 6: Feed pipe 7: Developer containing residue 8: Clarified developer 9: Separation plate 10: Residue removal processing section 12: Tank Part 13: Partition plate 14: Liquid flow

Claims (15)

[Claims] 1. A developing method for forming a pattern by immersing or / and jetting a liquid into a liquid to remove an eluted component, wherein a developing residue is removed from the developing solution by a centrifugal separation mechanism. . 2. The developing method according to claim 1, wherein a part of the development residue is used again as a raw material in the same forming step. 3. A method for manufacturing a member for a plasma display, comprising using the developing step according to claim 1 in the forming step. 4. The method according to claim 3, wherein the forming step is an electrode forming step. 5. The method for manufacturing a member for a plasma display according to claim 3, wherein the forming step is a rib forming step. 6. The method according to claim 3, wherein the forming step is a phosphor layer forming step. 7. The method according to claim 3, wherein the forming step is a black matrix or black stripe forming step. 8. The method according to claim 3, wherein the forming step is a color filter forming step. 9. A developing apparatus used in the developing method according to claim 1, further comprising a residue removing section, wherein the centrifugal separation mechanism is a decanter system. 10. The developing device according to claim 9, wherein the inside of the centrifugal separation mechanism is subjected to wear resistance processing. 11. The developing device according to claim 9, further comprising a separation plate inside the centrifugal separation mechanism. 12. The developing device according to claim 9, wherein the residue removing unit has a filter mechanism. 13. The developing device according to claim 9, wherein the developing solution is taken out from a tank portion for stirring and controlling the temperature, passed through a residue removal processing portion, and then returned to the tank portion again. apparatus. 14. The developing device according to claim 13, wherein an outlet for developing solution guided to the residue removal processing section is provided above the return port. 15. The developing device according to claim 14, wherein said tank section is divided into at least two places and has a cascade structure.