JP2001104857A - Fluoresent ink coating device and method of manufacturing gas discharge panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing gas discharge panel capable of excellently forming a fluoresent layer by precisely and efficiently applying a fluoresent ink, a fluoresent ink nozzle used in the manufacturing method and a fluoresent ink applying device provided with the same, in the manufacture of the gas discharge panel such as particularly PDP having high precise structure. SOLUTION: The stagnation of the fluoresent ink is eliminated by providing discharge ports 505-508 in the side surface of an ink base 504 adjacent to the ink nozzle 509 of a nozzle unit 500 in addition to the ink nozzle and passing the fluoresent ink through the discharge ports 505-508.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phosphor ink applying apparatus and a method for manufacturing a gas discharge panel, and more particularly to a technique for applying a phosphor ink with high precision to a gas discharge panel having a high definition structure.

[0002]

2. Description of the Related Art In recent years, high-definition display (high-definition, etc.)
There has been a demand for higher performance displays, such as larger screens and larger screens, and various displays have been researched and developed. As a typical display, CR
Examples include a T display, a liquid crystal display (LCD), and a plasma display panel (PDP).

[0003] Among them, PDP is a kind of gas discharge panel, and two thin glass plates are opposed to each other via a partition (rib), and a phosphor ink is applied between the partitions to form a phosphor layer. A discharge gas is sealed between the two glass plates and hermetically bonded, and discharges in the discharge gas to emit fluorescent light. Therefore, it is excellent in that a depth size and a weight are hardly increased like a CRT even when the screen is enlarged, and a problem that a viewing angle is limited like an LCD can be avoided. In recent PDPs, even high-definition PDPs of 50 inches or more have been manufactured.

By the way, in order to produce a high-definition PDP,
For example, in a 42-inch class high-vision PDP, the number of pixels is 1920 × 1125, and the cell pitch is 0.14 mm × 0.4.
A performance of 5 mm and a unit cell area of about 0.063 mm ² is required. This is the PD of the current NTSC system, etc.
The structure is considerably higher than that of P. Along with this, it is necessary to form a fine phosphor layer suitable for high vision and the like.

However, in the process of applying the phosphor ink, a problem is likely to occur if the phosphor ink is generally applied with a high definition to a high-vision class. For example, in the screen printing method, the partition pitch is 0.1 mm to 0.15.
mm, the width between the partition walls that can be filled with the phosphor ink is 0.1 mm or more due to the influence of the thickness of the partition walls.
It becomes very narrow, about 0.08 mm. If a phosphor ink having a higher viscosity (tens of thousands of centipoise) than originally intended is to be applied efficiently and accurately to the narrow width, a problem arises in that phosphor ink of another color enters the adjacent partition walls and causes color mixing. .

On the other hand, for example, Japanese Patent Laid-Open No. 10-1925
No. 41 discloses an inkjet (line jet) method in which phosphor ink is discharged from fine nozzles, and the phosphor ink is filled and applied between partition walls. Here, FIG. 7A is a front sectional view of a nozzle unit 900 used in the ink jet method. The nozzle unit 90
Reference numeral 0 denotes a housing 903 formed by cutting out stainless steel and a lid 9.
The phosphor ink supplied from the supply port 902 is filled in the ink space 905 and is discharged from the ink nozzle 904 at a constant pressure (for example, 4 to 5 kg / cm ² ). . Ink nozzle 904
Are adjusted in accordance with the size between the partition walls to which the phosphor ink is applied, and are arranged in parallel at regular intervals. This makes it possible to simultaneously apply the phosphor ink between the plurality of partition walls.

[0007]

However, according to this method, as shown in FIG. 8 (a), the phosphor ink supplied from the supply port 902 has a variation in ink flow over the entire ink space 905. For this reason, the phosphor particles may gradually settle in the side area of the ink space 905 near the ink nozzle 904 and settle down. When the phosphor particles settle in this way, the shape near the ink nozzle 904 in the ink space 905 substantially changes, and the phosphor ink does not flow in the original flow direction intended at the time of design. Then, the discharge direction of the phosphor ink emitted from the ink nozzle 904 is not determined (in this case, not along the z direction), and the phosphor ink deflects in another direction. This may cause problems such as color mixing of the phosphor ink, or the uneven application of the phosphor ink to significantly deform the phosphor layer. Further, the ink nozzle 904 itself may be clogged.

[0008] In the method of applying the phosphor ink using the ink nozzle as described above, there seems to be some room to be solved in order to apply the phosphor ink stably and accurately. The present invention has been made in view of such a point, its purpose is to:
In particular, in manufacturing a gas discharge panel such as a PDP having a high-definition structure, a method of manufacturing a gas discharge panel capable of forming a phosphor layer by applying a phosphor ink with high accuracy and efficiency. And a phosphor ink nozzle used in the manufacturing method, and a phosphor ink application device including the same.

[0009]

In order to solve the above-mentioned problems, the present invention discharges a phosphor ink supplied from the outside into a liquid chamber toward a coating object through a discharge port communicating with the liquid chamber. As the phosphor ink nozzle, an outflow hole is formed in the side surface of the liquid chamber to eliminate the stagnation of the phosphor ink in the liquid chamber by guiding the ink out of the liquid chamber.

By providing the outflow holes as described above, the ink flows in the area of the liquid chamber where the phosphor ink is liable to stagnate, and the stagnation generated when there is no outflow hole is eliminated. Further, sedimentation of the phosphor particles near the nozzle in the liquid chamber can be suppressed. Therefore, it is possible to apply the phosphor ink with high accuracy and high efficiency.

In a general ink nozzle, the liquid chamber is formed in such a shape that the cross-sectional area gradually decreases as approaching the discharge port. It is effective. The ink nozzle of the present invention described above specifically includes a phosphor ink supply unit that supplies ink to the liquid chamber of the phosphor ink nozzle, and a fluorescent ink that collects ink that has flowed out of the liquid chamber from the outlet hole. When the device is used as a phosphor ink coating device including a body ink recovery unit, the above-described effects are remarkable, and a coating target can be coated with a high yield, which is desirable.

Further, when the phosphor ink applying device is configured so that the ink collected by the ink collecting means is resupplied to the phosphor ink nozzle or the phosphor ink supply means, the relatively expensive phosphor ink is used. Can be used efficiently. Here, the phosphor ink nozzle may be mounted on the processing head in a phosphor ink coating apparatus having a processing head that is relatively movable along a surface of a table on which a coating target is placed. Also in this case, if the ink collected by the ink collecting means is re-supplied directly to the phosphor ink nozzle or via the phosphor ink supply means, the application efficiency of the phosphor ink is improved.

The present invention also provides a method of manufacturing a gas discharge panel, wherein a phosphor ink nozzle is moved along a longitudinal direction of the partition wall with respect to a panel surface of the gas discharge panel on which a plurality of partition walls are arranged. By performing a phosphor ink applying step of applying the phosphor ink to the gap between the partition walls through the nozzle discharge ports, a phosphor layer can be favorably formed even in a gas discharge panel having a fine structure such as a high vision system.

In this phosphor ink application step, if the ink that has flowed out of the liquid chamber through the outlet of the phosphor ink nozzle is collected and supplied again to the liquid chamber, a gas discharge panel can be manufactured with a higher yield. It is.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION 1. First Embodiment Hereinafter, a phosphor ink applying apparatus according to an application example of the present invention and a method of applying a phosphor ink to a gas discharge panel (PDP) using the same will be described. Will be described later. Here, first, a basic configuration of a PDP manufactured by applying a phosphor ink before a phosphor ink applying apparatus will be described.

1-1. Basic Configuration of PDP FIG. 1 shows a main configuration of an AC surface discharge type PDP (hereinafter simply referred to as "PDP") in which phosphor ink is applied by a phosphor ink applying apparatus of the present invention. It is a partial sectional perspective view. In the figure, the z direction corresponds to the thickness direction of the PDP, and the xy plane corresponds to a plane parallel to the panel surface of the PDP. This PDP
Is designed to meet the 42-inch class HDTV specifications. In all of the following FIGS. 1 to 8, it is assumed that the xyz directions match.

As shown in FIG. 1, the present PDP comprises a front panel 20 and a back panel 26 arranged with their main surfaces facing each other. A front panel glass 21 serving as a substrate of the front panel 20 has a band-shaped transparent electrode 220 having a thickness of 1.0 μm and a width of 120 μm on one surface thereof.
(230) and bus line 2 having a thickness of 5 μm and a width of 40 μm
21 (231) and the display electrode 22 (23) (X
A plurality of pairs of electrodes 23 and Y electrodes 22 are arranged along the x direction, and a gap (about 60 μm) between each pair of display electrodes 22 and 23 is provided.
To perform surface discharge.

The front panel glass 21 on which the display electrodes 22 and 23 are disposed is coated with a dielectric layer 24 having a thickness of about 20 μm over the entire main surface of the glass 21, and is further coated on the dielectric layer 24 with a thickness of about 20 μm. A 0.9 μm protective layer 25 is coated. A back panel glass 27 serving as a substrate of the back panel 26 has a thickness of 5 μm and a width of 40 μm on one surface thereof.
A plurality of address electrodes 28 having a thickness of 15 μm are arranged in a stripe pattern at regular intervals (about 140 μm) with the y direction as a longitudinal direction, and a dielectric layer having a thickness of 15 μm is provided on the entire surface of the front panel glass 21 so as to include the address electrodes 28. The body film 29 is coated. On the dielectric film 29, a height of 120 μm is set according to the gap between the adjacent address electrodes 28.
m, a partition wall 30 having a width of 40 μm is provided, and any one of red (R), green (G), and blue (B) is provided on the side surface of the adjacent partition wall 30 and the surface of the dielectric film 29 therebetween. Phosphor layers 31 to 33 formed by applying corresponding phosphor inks are formed. Each of these RGB phosphor layers 31 to 33 has x
Are sequentially arranged in the direction.

The front panel 2 having such a configuration
0 and the back panel 26 are adhered and sealed at the outer peripheral edges of the panels 20 and 26 while the address electrodes 28 and the display electrodes 22 and 23 are opposed to each other so that their longitudinal directions are orthogonal to each other. He, Xe,
A discharge gas (filled gas) composed of a rare gas component such as Ne is at a predetermined pressure (conventionally, usually about 500 to 760 Torr).
Enclosed.

A discharge space 38 is formed between the adjacent partition walls 30, and a region where a pair of adjacent display electrodes 22 and 23 and one address electrode 28 intersect with the discharge space 38 interposed therebetween is a cell (not shown) for image display. ). The cell pitch in the x direction is about 140 μm, and the cell pitch in the y direction is about 420 μm. When driving this PDP, one of the address electrodes 28 and the display electrodes 22 and 23 (in this embodiment, this is set to X
The electrode 23 is used. In general, the X electrode 23 is called a scan electrode, and the Y electrode 22 is called a sustain electrode. A pulse is applied to the cells to discharge them, thereby performing a write discharge (address discharge) on each cell. 2
Pulses are applied to the electrodes 2 and 23 to discharge them, thereby generating short-wavelength ultraviolet rays (Xe molecular beam having a center wavelength of about 173 nm) and causing the phosphor layers 31 to 33 to emit light, thereby displaying an image. .

In the PDP having the above-described structure, a panel luminance of about 480 cd / cm ² was obtained when discharging was performed at a discharge sustaining voltage of 150 V and a frequency of 30 kHz in an actual driving experiment. Next, an example of a method for manufacturing the PDP will be described. 1-2. Fabrication Method of PDP 1-2-1. Fabrication of Front Panel Display electrodes 22 and 23 are fabricated on a surface of a front panel glass 21 made of soda lime glass having a thickness of about 2.8 mm. For this, first, the transparent electrodes 220 and 230 are formed by the following photo etching method or the like.

A photoresist (for example, an ultraviolet curable resin) is applied on the entire surface of the front panel glass 21 to a thickness of about 0.5 μm. Then, a photomask having a pattern of the transparent electrodes 220 and 230 is superimposed thereon and irradiated with ultraviolet rays, and is immersed in a developing solution to wash out uncured resin. Next, the transparent electrode 22
ITO (Indium Tin Oxide) or the like is applied to the resist gap of the front panel glass 21 as a material of 0, 230. Thereafter, the resist is removed with a cleaning solution or the like, and the transparent electrodes 220 and 230 are completed.

Subsequently, the transparent electrodes 220 and 23 are formed of a metal material containing Ag or Cr / Cu / Cr as a main component.
The bus lines 221 and 231 having a width of 40 μm are formed on 0. When Ag is used, a screen printing method can be applied. When Cr / Cu / Cr is used, a vapor deposition method or a sputtering method can be applied. Thus, the display electrodes 22 and 23 are formed.

Next, lead oxide (PbO), boron oxide (B ₂ O ₃ ), silicon oxide (Si
O ₂ ) is coated over the entire surface of the front panel glass 21 by a screen printing method using a material obtained by mixing the respective components in a weight ratio of 70:15:15, and baked (for example, 520).
(At 10 ° C. for 10 minutes) to form a dielectric layer 24 having a thickness of about 20 μm.

Next, a protective layer 25 made of magnesium oxide (MgO) and having a thickness of about 0.9 μm is formed on the surface of the dielectric layer 24 by, for example, a sputtering method. Thus, the front panel 20 is manufactured. 1-2-2. Fabrication of Back Panel On a surface of a back panel glass 27 made of soda-lime glass having a thickness of about 2.8 mm, a conductive material mainly composed of silver (Ag) is screen-printed at regular intervals. And an address electrode 28 having a thickness of about 40 μm.
To form

Subsequently, a lead-based glass paste having a thickness of about 20 to 30 μm is applied over the entire surface of the back panel glass 27 on which the address electrodes 28 are formed and baked to form a dielectric film 29. Next, using the same lead-based glass material as the dielectric film 29, a height of about 120 μm is formed on the dielectric film 29 at every gap (about 140 μm) between the adjacent address electrodes 28.
m partition walls 30 are formed. The partition walls 30 can be formed by, for example, repeatedly screen-printing a paste containing the above-described glass material and then firing the paste.

After the partition 30 is formed, the red (R) phosphor, the green (G) phosphor, and the blue (R) phosphor are formed on the wall surface of the partition 30 and the surface of the dielectric film 29 exposed between the adjacent partitions 30. B) A fluorescent ink containing any of the phosphors is applied, and dried and fired (for example, at 500 ° C. for 10 minutes) to form phosphor layers 31 to 33, respectively. Examples of phosphor materials generally used for PDPs are listed below.

A red phosphor; (Y _x Gd _1-x ) BO ₃ :
Eu ³⁺ (or YBO ₃ : Eu ³⁺ ) green phosphor; Zn ₂ SiO ₄ : Mn (or BaAl)
₁₂ O _19: Mn) · blue ^{_{phosphor; BaMgAl 10 O 17: Eu 3+}} ( or BaMgAl ₁₄ O _23: Eu ³⁺⁾ each phosphor material, for example a powder having an average particle size of about 2μm can be used. The details of the application of the phosphor ink will be described later.

Thus, the back panel 26 is completed. 1-2-3. Completion of PDP Front panel 20 and back panel 26 prepared above
Are bonded together using sealing glass. Thereafter, the inside of the discharge space 38 is evacuated to a high vacuum (4 × 10 ⁻⁷ Torr), and a predetermined pressure (500 to 800 Torr) is applied thereto.
Ne-Xe, He-Ne-Xe, He-Ne-Xe-A
A discharge gas such as an r-based gas is sealed. At this time,
The content of Xe is set to 5% by volume or more.

Thus, the present PDP is completed. 2. Detailed Method of Forming Phosphor Layer Next, a coating apparatus for applying a phosphor ink as a material of the phosphor layers 31 to 33 will be described. In the phosphor ink application device, the back panel 26 immediately after the address electrodes 28, the dielectric film 29, and the partition walls 30 are arranged on the back panel glass 27 in the above-described PDP manufacturing process is set.

2-1. Overall Configuration of Phosphor Ink Coating Apparatus FIG. 2 is a schematic external view of the phosphor ink applying apparatus used in the first embodiment. The phosphor ink coating device 10
Is an xy independent moving table, and the moving table 200
(Reciprocally movable in y direction) and machining head base 32
0 (movable back and forth in the x direction). In this embodiment, the processing head is the following nozzle tank 40
0, the configuration of the nozzle unit 500, and the like.

A rectangular table 101 serving as a base of the phosphor ink coating device 10 has a longitudinal direction (y direction).
A rail plate 102 is laid in parallel with the above. Both ends of the rail plate 102 in the width direction (x direction) are bent to form rails 1020R and 1020L, and a rail traveling body 201 having a ball retainer or the like built therein.
R and 201L are engaged respectively.

In the vicinity of both ends in the y direction of the rail plate 102,
A pulley 104 (shown on the near side of the paper) and a guide pulley (not shown on the back side of the paper) are installed.
Through the pulley 104,... To the timing belt 105
Is stretched. The pulley 104 is directly connected to the drive shaft of the stepping motor 103, and the timing belt 105 is driven to rotate.

With such a configuration, the moving table 2
00 is a table body 203 of a plate body having a longitudinal direction in the y direction and a main surface in the xy plane, and the rail traveling bodies 201R, 201 at both ends in the x direction of the table body 203.
L is fixed with screws 202. Further, the table body 203 is connected to the timing belt 105 by a known mechanism (not shown).

Therefore, the moving table 200 is driven by the rotation of the stepping motor 103 by the timing belt 1.
05 etc., the rail running body 201R,
By moving the 202L along the rails 1020R and 1020L, precise reciprocating movement in the y direction is possible. The back panel 26 is mounted on the table body 203 as shown in the figure, and is fixed by a known suction fixing mechanism (vacuum chuck method) or the like.

On the other hand, a rail plate 102
The bridge portion 300 is arranged around an inverted U-shaped bridge 301 fixed so as to straddle the bridge. The bridge section 300 is provided with a mechanism for driving the processing head base 320. That is, as shown in FIG.
0, a ball screw 311 and a rail guide 312 having a concave cross section along the yz plane are provided.
The ball screw 311 is rotatably held by bearings 313 and 314, and its shaft is connected to a pulley 315 and a V-belt 31.
6. The rotational driving force of the stepping motor 318 is transmitted via the pulley 317.

The processing head base 320 is, as shown in FIG.
A plate having a main surface on an xz plane with the z direction as a longitudinal direction, and having a shape in which a thickness portion is perforated at two places in the x direction. The shaft 310 and the ball screw 311 are passed through the perforated portion, and are held so as to be guided by the rail guide 312. Thus, when the stepping motor 318 rotates, the processing head base 320 is controlled to reciprocate precisely in the x direction along the shaft 310 and the rail guide 312.

With the above configuration, the moving table 200
(And the workpiece mounted thereon; in this case, the back panel 26) and the processing head base 320 are precisely driven by each of the stepping motors 103 and 318, and relatively x
Move in y direction. An ink tank 400 and the like are mounted on the processing head base 320, and a phosphor ink of several tens of micro-orders based on two-dimensional coordinates is applied to the back panel 26 as described below.

Note that these stepping motors 10
The operations of 3, 318 and the like are controlled by a control unit (not shown) including a microcomputer including a CPU, a storage unit, an input unit for an operator, and the like. The control unit also drives the air pump 600 and the circulation pump 700 mounted on the bridge unit 300 by the fixtures 602 and 703, together with the stepping motors 103 and 318, based on the control program stored in the storage unit. Control and
A phosphor ink application process described later is executed.

As such a control unit, a PC
A (personal computer) type is used. 2-2. Configuration around processing head base 320 Next, a configuration around the processing head base 320 will be described.
As shown in FIG. 2, the processing head base 320 has a processing head height adjusting plate 32 provided with a rack portion 323 in the z direction.
1, and a processing head fixing plate 322 to which the ink tank 400 and the like are fixed is mounted on the main surface of the processing head height adjusting plate 321. Processing head height adjustment plate 32
On the other hand, the height of the processing head fixing plate 322 can be finely adjusted along the z direction by a mechanism of a pinion (not shown) and the rack portion 323.

The tip of the ink tank 400 (bottom in the z direction)
Is fixed to the nozzle unit 500 having the main features of the present invention. The ink tank 400 and the nozzle unit 500 are connected to the air pump 600, the circulation pump 700, and a predetermined pipe L1,. (To be described later). Here, FIG.
00 and a front view of the nozzle unit 500, FIG.
Are their side views.

As shown in this figure, the processing tank fixing plate 322 is provided with an ink tank 400 having a cylindrical main body 401 and a conical tip 402 with the tip 402 directed downward (vertically) in FIG. Fixing tool 410, bolt 41
2B, nuts 412N, bolts 413 and the like. The inside of the ink tank 400 is hollow, and the nozzle unit 500 is attached to the front end portion 402, and the ink tank 400 is hermetically sealed with a cap 404 from above. The tip portion 402 is specifically fixed while being pressed toward the nozzle unit 500 side. A valve 405 is interposed between the tip 402 and the main body 401. By rotating the valve 405 along the circumferential direction of the ink tank 400, the flow rate of the ink inside can be controlled.

At the center of the cap 404 located at the uppermost part of the ink tank 400, a pipe L1 is fixed by nuts 420 and 421, and a predetermined pressure (4 to 5 kg / cm ² during normal operation) is applied from the pump 600. Compressed air is supplied into the ink tank 400. An annular spacer 403 is arranged below the cap 404. The pipe L2 is fixed to this by a fixture 4030 including washers 4031 and 4032, a hollow bolt 4033, and the like.
The phosphor ink in the nozzle unit 500 is discharged from the circulation pump 700 via the pipe L2, and the ink tank 4
00 is resupplied.

Incidentally, P1 to P4 in the figure are packings for maintaining confidentiality in the ink tank 400 and between the ink tank 400 and the nozzle unit 500. The nozzle unit 500 is fixed to the processing head fixing plate 322 by tightening bolts 331, 341 and 342 via a spacer 330 and a holder 430. Then, the phosphor ink supplied from the ink tank 400 is discharged by a mechanism described later.

Here, the nozzle unit 500
Is a main feature of the present embodiment. 2-3. Configuration of Nozzle Unit FIG. 4 is a diagram showing the configuration of the nozzle unit. In this figure,
(A) is an assembly perspective view of the nozzle unit 500, (b) is a front transparent view of the nozzle unit main body 503 viewed from the yz plane, and (c) is a nozzle unit main body 50 viewed from the xz plane.
3 is a front transparent view of FIG.

The nozzle unit 500 shown in FIG.
Is basically used in an ink jet (line jet) system, and includes a nozzle unit main body 503 and a lid portion 501. These are both stainless steel (SUS
304) After the material is machined with a lathe and made,
The surface is mirror-finished by electropolishing so that the frictional resistance to the phosphor ink flowing through the inside is reduced as much as possible.

Although not shown, the lid portion 501 and the nozzle unit main body 503 are fitted to each other via a packing, and are fastened and fixed by a plurality of screws. The lid portion 501 is a plate member, and has a structure in which an ink supply port 501 into which the tip end portion 402 of the ink tank 400 is inserted is bored in the center of the main surface. The nozzle unit body 503 has an ink space (liquid chamber) 504 whose inside is hollowed out like a bathtub and whose diameter decreases toward the bottom surface {FIG.
(C) A rectangular parallelepiped member on which reference｝ is formed, and 6 lines in a line along the z direction at the center of the bottom surface of the ink space 504.
An ink nozzle 509, which is an ink discharge port perforated over the hole (see FIG. 7C), and four discharge ports (outflow holes) 505 perforated so as to communicate with the outside from each side of the ink space 504. 508.

As an example of the size of the ink nozzle 509, the ink nozzle 509 has a nozzle diameter of 60 μm, and is arranged so that the center distance between adjacent nozzle diameters is 1260 μm. This value is determined by the gap (14
0 μm), among the three color phosphor layers of RGB each formed three times the gap between adjacent phosphor layers of the same color 色 one cell pitch (140 × 3) μm × 3 times pitch = 1260 μ for one color
m｝. As described above, in the nozzle unit main body 503, by disposing the ink nozzles 509 at a certain interval, the jet flow of the phosphor ink may interfere due to the influence of electrostatic force or the like at the time of ejection, or the ejection direction may be distorted. I try not to.

The outlets 505 to 508 are a major structural feature of the present embodiment that has not been seen in the prior art.
Perforated along any of the directions.
The outlets 505 to 508 are threaded together with the holes, and are provided with the same fixing tool 5 as the fixing tool 4030.
20 to 550 (see FIG. 3) are screwed and fixed, respectively, and the pipes L3 to L6 are connected. These pipes L3 to L6 together with the pipe L2 form the following circulation path of the phosphor ink.

2-4. Circulating Path of Phosphor Ink FIG. 5 shows an ink tank 400, a nozzle unit 500,
FIG. 4 is a schematic diagram specifically illustrating a circulation path of phosphor ink through each pipe connecting a circulation pump 700. Here, a supply path of compressed air to the ink tank 400 by the air pump 600 and the pipe L1 is also illustrated.

As shown in the figure, first, compressed air is supplied from the discharge port 601 of the air pump 600 to the ink tank 400 through the pipe L1. The phosphor ink in the ink tank 400 is supplied from the ink tank 400 to the nozzle unit 500 by the pressure of the pressurized air. Nozzle unit 5
At 00, while the phosphor ink is being ejected from the ink nozzle 509 (see FIG. 7), the phosphor ink is circulated outside the nozzle unit 500 through the pipes L3 to L6.

The phosphor ink flowing through the pipes L3 to L6 is collected again in the coupler 800, and is connected to one pipe L7.
Is supplied to the suction port 702 of the circulation pump 700 through the The phosphor ink supplied to the circulation pump 700 flows through the pipe L2 from the discharge port 701, and the ink tank 400
Is supplied again. As described above, in the present embodiment, the circulation pump 700 serves as both an ink supply unit and an ink resupply unit.

The above is the general circulation route of the phosphor ink. 3. About Phosphor Ink Here, examples of the components of the phosphor ink used in the present phosphor ink coating device 10 will be given. The phosphor ink application device can basically use a general phosphor ink. For example, in the case of a blue phosphor ink, the average particle size is 2 μm.
m blue phosphor (BaMgAl ₁₀ O ₁₇ : Eu ³⁺ ) 30w
t%, ethyl cellulose (molecular weight: about 200,000) 4.5 wt
%, Dispersant (glycertrioleate) 2 wt%, silicon oxide particles (silica particles) 1 w having an average particle diameter of 0.01 μm
t%, solvent (butyl carbitol acetate) 62wt
% And a plasticizer 0.5 wt%, and the mixture is stirred well to about 100 centipoise (cp).

4. P using phosphor ink coating device 10
Step of Applying Phosphor Ink to DP Next, the step of applying phosphor ink to PDP using the present phosphor ink applying apparatus 10 will be specifically described. 4-1. Various Settings of Phosphor Ink Coating Apparatus First, on the moving table 200 of the phosphor ink applying apparatus 10 having the above configuration, pay attention to the direction of the back panel 26 (the xy direction of the back panel Then, the back panel 26 is horizontally fixed on the moving table 200.

Subsequently, the rack 323 is adjusted to adjust the ink nozzle 509 of the nozzle unit 500 and the back panel 2.
The distance between the partition walls 30 of No. 6 is reduced to about 500 μm.
This is for the purpose of preventing adverse effects such as splash of phosphor ink and color mixing between adjacent cells caused by poor straightness (bending) of the ink flow ejected from the nozzle holes. Next, the discharge force of the pump 600 and the circulating pump 700 is adjusted from the operator input unit of the control unit of the phosphor ink application device 10 so that the ink discharge force from the ink nozzle 509 is 4 to 5
Set in the range of kg / cm ² . Then, following this setting, the speed condition of the coating process (stepping motor 1
03, 318, etc.) to complete the setting of the overall phosphor ink application process.

In the present embodiment, the back panel 26
Among the RGB colors to be applied to each other, a phosphor ink application process for applying one color of phosphor ink is exemplified. However, when the phosphor ink application process for all colors is performed continuously, the phosphor ink is applied. After applying one color of ink, the apparatus is temporarily stopped, and the ink tank 400 and the nozzle unit 5 are stopped.
It is necessary to perform a cleaning operation such as 00.

4-2. Phosphor Ink Application Process After setting the phosphor ink application process, when a work start instruction is input, the phosphor ink application process is automatically started. The ink application process is performed, for example, as shown in FIG. In the figure, a dashed line arrow parallel to the x direction is
The processing head base 320 side provided with the ink tank 400, the nozzle unit 500, etc.
A solid line arrow parallel to the y-direction indicates the moving direction of the moving table 200 (including the back panel 26). The “effective application range” indicates the range of the phosphor ink actually applied on the back panel 26.

As shown in FIG. 6, the phosphor ink application process includes three continuous processes (first to third scanning processes). In this figure, the number of times of movement of the table and the number of times of movement of the processing head base are less than the actual number for the sake of simplicity. In addition, the table movement direction lengths (stroke lengths) of the first to third scanning processes are displayed with a difference, but this is to make it easy to understand the operation direction of each scanning process. , And takes a stroke value slightly longer than the length of the back panel 26 in the y direction.

4-2-1. First Scanning Process The first scanning process is started after the left end nozzle of the ink nozzle 509 is positioned between the predetermined partition walls 30 below the leftmost end of the back panel 26 in the x direction. At this time, "
lower side of the paper than the position where "start" is displayed (back panel 2
The phosphor ink is ejected in advance in the y direction (on the y-direction side from 6). The discharge of the phosphor ink is continuously maintained until the end of a third scanning process described later.

The ink nozzle 509 and the back panel 2
6, the movable table 200 is scanned in the y-direction at a stretch (about 0.5 m to 1.7 m / sec).
c) Apply phosphor ink between predetermined partition walls 30. Since the ink nozzles 509 have a total of six holes, phosphor inks corresponding to a total of six phosphor layers are simultaneously applied at this time. Here, FIG. 7 shows a state in which the phosphor ink is applied to the back panel 26. The nozzle unit 500 is larger than it actually is, and the back panel 26 is partially illustrated. In FIG. 7, the back panel 2
6, the ink nozzle 509 is actually perforated at an interval of 1260 μm, so that the phosphor ink is applied between the partition walls 30 every nine grooves (one groove width 14).
0 μm × three colors × 3 times = 1260 μm).

When the conventional nozzle unit 900 shown in FIG. 8A is used, the ink supply port 902
Most of the supplied phosphor ink is ejected from the ink nozzle 904, but a small amount of phosphor particles are present in a region in the ink space 509 where the ink flow is likely to stagnate, that is, a side region of the ink space 509 near the ink nozzle 904. May accumulate. This substantially changes the shape in the vicinity of the ink nozzle 904, causing the ejection direction of the phosphor ink ejected from the ink nozzle 904 to fluctuate, causing color mixing and the like. Also,
The formed phosphor layer is deformed or the ink nozzle 904
May cause clogging. Such a problem is likely to occur in a manufacturing process of a high-vision PDP having a relatively narrow partition pitch (cell pitch), and is considered to be a problem to be solved particularly.

On the other hand, in the embodiment of the present invention, as shown in the front sectional view of the nozzle unit 500 in FIG.
The four side surfaces are provided with perforations 505, 507 and the like (see FIGS. 4A and 4B for 506 and 508), and excess phosphor ink is discharged from the perforations to eliminate ink stagnation, and ink nozzles 509 are formed. The effect of keeping the discharge of the phosphor ink discharged from the satisfactorily can be obtained.

In addition, in this embodiment, in addition to this, the phosphor ink discharged from the discharge ports 505 to 508 is re-supplied to the ink tank 400 by the circulation pump 700 so that the phosphor ink which is originally easily costly can be efficiently used. It has a configuration that can be used well. After the phosphor phosphor ink has been applied at once in the y direction, the moving table 200
The back side 26 is moved to a position outside the vertical position below the ink nozzles 509 on the processing head base 320 so that the phosphor ink is not applied to the back panel 26. Then, the processing head base 320 side is moved in the x direction, and preparation for coating between the new partition walls 30 is started. At this time, the moving distance on the processing head base 320 side is 8820 μm.
｛(Ink nozzle 509 interval for 6 holes 1260 × 6μ
m) +1260 μm = 8820 μm) with a speed of 1.
It moves at about 0 to 10 m / sec.

When the movement of the processing head base 320 is completed, the phosphor ink is applied again in the same manner as described above (except that the y direction is reversed). The above operation is repeated by a predetermined number according to the standard size of the back panel 26, and after performing over the entire surface of the back panel 26,
The first scanning process ends. Thus, the scanning process as a whole consists of zigzag movements in the xy directions.

In the first scanning process alone, only one third of the target number of phosphor layers of the same color is applied because of the nozzle spacing of the ink nozzles 509.
It is necessary to continue the second scanning process and the third scanning process in the same manner as the scanning process. 4-2-2. Second Scanning Process The second scanning process is performed continuously after the end of the first scanning process. According to FIG. 6, after the last application of the first scanning process is completed, the processing head base 320 is slightly moved along the x direction in a direction opposite to that in the first scanning process. The moving amount at this time is 420 μm, that is, the adjacent phosphor layer pitch of the same color (140 μm × 3 = 420 μm). After the movement of the processing head base 320, the second scanning process is started from the position indicated as "start" in FIG. The content of the second scanning process is the same as that of the first scanning process, and thus will not be described.

4-2-3. Third Scanning Process When the second scanning process is completed, the process proceeds to the third scanning process which is the last scanning process. At this time, between the second scanning process and the third scanning process, the processing head base 320 is slightly moved along the x direction in the same direction as the second scanning process. The moving amount is the same as above 42
0 μm. After this, the moving direction of the processing head base 320 side in the third scanning process is the same as that in the first scanning process due to the positional relationship between the applied partition walls 30.

When the third scanning process started from the position indicated as “start” in FIG. 6 is completed (to reach “end”), the moving table 200 is moved in the y direction as it is, and the back panel 26 is positioned immediately below the ink nozzle 509. The discharge of the phosphor ink is stopped at the position where the is completely shifted. This completes the phosphor ink application process for the phosphor layer for one color of the back panel 26.

5. Other Matters In the above-described embodiment, the application of the phosphor ink to the PDP of the Hi-Vision system has been described as an example. However, it is needless to say that PDPs of other systems (PDPs of the conventional NTSC system may be used). Alternatively, the present invention may be applied to other types of gas discharge panels to produce the panel.

The present invention also relates to an ink jet method (method).
However, the present invention is not limited to this, and may be applied to any other coating method as long as the nozzle has an ink space (liquid chamber) and an ink nozzle. The phosphor ink application device is not limited to the illustrated system, but may be another system (for example, a system in which the processing head base is fixed and the moving table moves in the xy directions).

Further, in the embodiment, the gap between the adjacent ink nozzles 509 is set to 1260 μm. However, the present invention is not limited to this.
May be changed according to the standard, size, etc. However,
Needless to say, by changing the gap between the adjacent ink nozzles 509, it is necessary to adjust the ink application process accordingly (for this, for example, a method of increasing or decreasing the number of scanning processes can be considered). Also, the number of ink nozzles 509 is not limited to six, and may be other numbers.

Further, the discharge ports 505 to 505 of the nozzle unit
Although all four 508s have the same shape, the number of outlets is not limited to this. Also, outlets 505 to 508
Is not limited to a circular shape. For example, the discharge port (50) on the longitudinal side surface of the bathtub-shaped ink space may be used.
6, 508, see FIG. 4) may be formed into an elliptical shape or a rectangular shape extending in the longitudinal direction, so that the stagnation of the phosphor ink in the ink space is more effectively eliminated.

Regarding the above-mentioned 505 to 508, one of them is called a discharge port, and the other is called a supply port.
They may be used separately. In the above-described embodiment, an example in which the discharge ports 505 to 508 are provided in the side surface area of the ink space 504 close to the ink nozzle 509 has been described. However, the present invention is not limited to this. May be disposed in an area where stagnation is likely to occur. However, when the outlet is provided at the position shown in the embodiment, the ink nozzle 509 is not provided.
It is desirable because the stagnation of the surrounding ink is satisfactorily eliminated.

Further, in the above embodiment, the circulation pump 7
00, the phosphor ink is collected from the nozzle unit 500 and supplied to the ink tank 400 again. However, the present invention is not necessarily limited to this configuration.
A tank (phosphor ink collecting means) for collecting the phosphor ink discharged from the apparatus may be provided, and the collected phosphor ink may be reused as appropriate.

The reason why the scanning process is composed of three stages in the present embodiment is that the scanning process is adjusted to the nozzle gap of the ink nozzle 509. Therefore, the scanning process is actually adjusted appropriately to the nozzle interval of the manufactured ink nozzle 509. Needless to say, the number of times needs to be changed. In the above-described phosphor ink application process, an alignment mark is attached in advance to a predetermined position of the pack panel glass 27, and the alignment mark is read by a CCD or the like provided on the phosphor ink application device 10 side to perform more precise alignment. After that, the phosphor ink may be applied.

[0075]

As is apparent from the above description, the present invention provides a phosphor ink nozzle for discharging a phosphor ink supplied from the outside into a liquid chamber toward an object to be coated through a discharge port communicating with the liquid chamber. As an outflow hole is formed on the side of the liquid chamber, which eliminates the stagnation of the phosphor ink in the liquid chamber by inducing outflow to the outside of the liquid chamber. The flow of ink occurs in the region, the stagnation is eliminated, and the phosphor ink can be applied with high accuracy and high efficiency.

Therefore, the coating apparatus provided with the phosphor ink nozzle of the present invention makes it possible to satisfactorily apply the phosphor ink even to a gas discharge panel such as a PDP having a fine structure such as a high-vision system. The phosphor layer can be formed with high accuracy.

[Brief description of the drawings]

FIG. 1 is a partial schematic view of a plasma display panel manufactured by a manufacturing method of the present invention.

FIG. 2 is a schematic view of a phosphor ink application device as one application example of the present invention.

FIG. 3 is a diagram illustrating a configuration of an ink tank and a nozzle unit. (A) is a front view of an ink tank and a nozzle unit. (B) is a side view of the ink tank and the nozzle unit.

FIG. 4 is a schematic diagram illustrating a configuration of a nozzle unit.
(A) is a schematic assembly drawing of a nozzle unit. (B) is a side view of the nozzle unit main body. (C) is a side view of the nozzle unit main body.

FIG. 5 is a diagram showing a circulation path of phosphor ink in the phosphor ink application device.

FIG. 6 is a diagram showing a phosphor ink application process.

FIG. 7 is a diagram illustrating a state around a nozzle unit when phosphor ink is applied.

FIG. 8 is a front sectional view showing a configuration of a conventional type and a nozzle unit of the present invention. (A) is a front sectional view of a conventional nozzle unit. (B) is a front sectional view of the nozzle unit of the present invention.

[Explanation of symbols]

 L1 to L8 Piping 10 Phosphor ink coating device 26 Back panel 30 Partition wall 31 to 33 Phosphor layer 102 Rail plate 103, 318 Stepping motor 105 Timing belt 200 Moving table 201R, 201L Rail running body 203 Table body 300 Bridge section 310 Shaft 311 Ball screw 312 Rail guide 315, 317 Pulley 316 V belt 320 Processing head base 322 Processing head fixing plate 400 Ink tank 402 Tank tip 403 Spacer 404 Cap 405 Valve 500 Nozzle unit 503 Nozzle unit body 504 Ink space 505-508 Discharge port 509 Ink nozzles 520 to 550, 4030 Fixture 600 Air pump 700 Circulation pump 800 Coupler 1020 , 1020L rail

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) H01J 11/02 H01J 11/02 B5C040 (72) Inventor Hiroyuki Kawamura 1006 Odakadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Shigeo Suzuki 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.F term (reference) 4D075 AC08 AC84 CA48 DA06 DB13 DC24 EA33 4F033 AA01 BA03 CA04 DA05 EA01 JA06 4F041 AA05 BA12 BA04 BA25 BA27 CB03 CB20 CC15 5C028 HH14 5C040 FA01 GA03 GB02 GG09 JA13 MA24

Claims (7)

[Claims] 1. A phosphor ink nozzle for discharging phosphor ink supplied from the outside into a liquid chamber through a discharge port communicating with the liquid chamber toward an object to be coated. A phosphor ink nozzle having an outflow hole that eliminates the stagnation of ink in the liquid chamber by inducing the ink to flow out of the liquid chamber. 2. The liquid chamber according to claim 1, wherein the liquid chamber is formed in such a shape that the cross-sectional area gradually decreases as approaching the discharge port, and the outflow hole is formed on a wall surface in which the cross-sectional area gradually decreases. 2. The phosphor ink nozzle according to 1. 3. The phosphor ink nozzle according to claim 1 or 2, a phosphor ink supply means for supplying ink to a liquid chamber of the phosphor ink nozzle, and collecting ink flowing out of the liquid chamber from the outlet hole. And a phosphor ink collecting means. 4. The processing head according to claim 3, further comprising a processing head that is relatively movable along a surface of the table on which the application target is placed, and wherein the phosphor ink nozzle is mounted on the processing head. The phosphor ink coating device as described in the above. 5. The phosphor according to claim 3, wherein the ink recovered by the ink recovery unit is re-supplied directly to the phosphor ink nozzle or via a phosphor ink supply unit. Ink coating device. 6. The phosphor ink nozzle according to claim 1 is moved along a longitudinal direction of the partition wall with respect to a panel surface of a gas discharge panel on which a plurality of partition walls are arranged in parallel, and a nozzle is inserted into a gap between the partition walls. A method for manufacturing a gas discharge panel, comprising a step of applying a phosphor ink through a discharge port. 7. The gas according to claim 6, wherein, in the phosphor ink applying step, the ink flowing out of the liquid chamber from the outlet hole of the phosphor ink nozzle is collected and supplied again to the liquid chamber. A method for manufacturing a discharge panel.