JP2005125181A - Coating method and coating apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating method capable of discharging/supplying various liquids such as an adhesive, clean solder, a fluorescent body, an electrode material, grease, paint, a hot melt, chemicals, food and the like at a high speed with high precision in a production process in a field of electronic parts, household electric products, a display and the like, and a coating apparatus. <P>SOLUTION: In a state that an electrode is preformed in the vicinity of the boundary part of the scheduled coating pattern formed on a substrate, a coating material is charged with charge having a predetermined code and, in a state that voltage having the same code as the charge is applied to the electrode, the coating material is supplied to the substrate to form the coating pattern. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a coating method and a coating apparatus with a minute flow rate required for various production processes such as information / precision equipment, machine tools, FA, and semiconductors, liquid crystals, displays, surface mounting, and the like.

Liquid discharge devices (dispensers) have been used in various fields in the past, but with the recent needs for downsizing electronic components and increasing recording density, a small amount of fluid material can be supplied with high accuracy and stability. Control technology is required. For example, in the field of displays such as plasma displays, CRTs, and organic ELs, there is a great demand for patterning phosphors and electrode materials directly on a panel surface without a mask, instead of conventional methods such as screen printing and photolithography. To summarize the issues of dispensers for that,
1) Finer application amount 2) Higher accuracy of application amount 3) Shorter application time.

  Conventionally, as a liquid ejecting apparatus, a dispenser by an air pulse system as shown in FIG. 31 has been widely used, and the technique is introduced in, for example, “Automation Technology '93 .25 No. 7”. The dispenser according to this system applies a constant amount of air supplied from a constant pressure source to the interior 601 of the container 600 (cylinder) in a pulsed manner, and a certain amount of liquid corresponding to the increase in pressure in the cylinder 600 is supplied from the nozzle 602. It is what is discharged.

  Development has been made to apply an ink jet method, which has been widely used as a consumer printer, as an industrial coating apparatus. FIG. 32 shows a conventional example of a head portion in an ink jet recording apparatus (Patent Document 1), 651 is a base, 652 is a diaphragm, 653 is a laminated piezoelectric element, 654 is an ink chamber, and 655 is a common ink chamber. , 656 are ink flow paths (throttle portions), 657 is a nozzle plate, and 658 is a discharge nozzle.

  When a voltage is applied to the piezoelectric element 653 that is a pressure applying means, the piezoelectric element 653 deforms the diaphragm 652 in the thickness direction, and the volume of the ink chamber 654 decreases. As a result, the fluid is compressed and the pressure in the ink chamber 654 increases, so that a part of the fluid flows back through the ink passage to the common ink chamber 655 side, but the remaining portion is discharged from the nozzle 658 to the atmosphere. .

  For the purpose of drawing ultrafine lines for plasma displays and the like, a high-viscosity fluid coating apparatus called an electric field jet method has been proposed (Patent Documents 2 and 3). This method is based on the discharge method using an electric field reported by Zeleny in 1917.

  33, 500 is a high-viscosity fluid, 501 is a control unit, 502 is a container, 503 is an opening, 504 is an electrode, 505 is a power source, 506 is a substrate to be coated (substrate to be coated), 507 is An extension part 508 of the coating fluid flowing out from the nozzle is a pressurizing means.

  The coating apparatus has an opening 503 such as a circular or polygonal orifice or nozzle having a hole diameter of about 50 μm to 1 mmφ at the lower part of the container 502, and an electrode 504 is disposed in a part of the opening 503. Yes. The container 502 is filled with a liquid coating material with a high-viscosity substance of 1000 to 1000000 cps. In order to pressurize the liquid coating material 500 filled in the container 502, pressurizing means 508 using high-pressure air is provided in connection with the container 502.

First, a pressure is applied to the liquid coating material in the container 502 to form a meniscus of the liquid coating material in the opening 503. Next, a first predetermined pulse voltage is applied between the electrode 504 of the nozzle opening 503 and the substrate to be coated 506 that is a counter electrode, and an elongated portion in which the meniscus of the liquid coating material is elongated vertically in the opening 503. In a state where 507 is formed, the fluid is allowed to flow from the distal end of the elongated portion. In this state, if the nozzle and the substrate to be coated 506 are moved relative to each other, the meniscus tip is sufficiently narrower than the nozzle diameter. Can be drawn.
Japanese Patent Laid-Open No. 11-10866 JP 2000-246887 A JP 2001-137760 A

  In recent years, in the field of circuit formation, which is becoming more highly accurate and ultra-fine, or in the field of manufacturing processes for electrodes, ribs and phosphor screens of liquid crystal display tubes such as PDP and CRT, liquid crystal, optical discs, organic EL, etc. Many of the fluid materials to be used are high viscosity powder fluids. In order to replace the conventional method with a direct patterning method using a dispenser, a minute amount of high-viscosity powder containing fine particles having an average outer diameter of several microns to several tens of microns, such as phosphors, conductive capsules, solder, and electrode materials The biggest challenge is how to apply fine fluid onto the target substrate with high reliability at high speed and high accuracy without clogging the flow path.

  Hereinafter, taking the phosphor layer forming process of the plasma display panel as an example, the following problems of the prior art will be described.

[1] Problems with screen printing and photolithography [2] Problems with direct patterning of phosphor layers using conventional dispenser technology First, the above [1] will be described.

(1) Structure of Plasma Display Panel FIG. 34 shows an example of the structure of a plasma display panel (hereinafter referred to as “PDP”). The PDP is roughly composed of a front plate 800 and a back plate 801. A plurality of sets of linear transparent electrodes 803 are formed on a first substrate 802 which is a transparent substrate constituting the front plate 800. The second substrate 804 constituting the back plate 801 is provided with a plurality of sets of linear address electrodes 805 orthogonal to the linear transparent electrodes. The two substrates are opposed to each other with a bias rib 806 on which a phosphor layer is formed, and a discharge gas is sealed in the bias rib 806. When a voltage equal to or higher than the threshold value is applied between the electrodes of both substrates, a discharge occurs at a position where the electrodes cross each other, and the discharge gas emits light, and the emitted light can be observed through the transparent first substrate 802. An image can be displayed on the first substrate side by controlling the discharge position (discharge point). In order to perform color display by PDP, a phosphor that develops a desired color by ultraviolet rays emitted during discharge at each discharge point is formed at a position corresponding to each discharge point (barrier rib partition). In order to perform full color display, RGB phosphors are formed.

  The configuration of the front plate 800 and the back plate 801 will be described in more detail.

  The front plate 800 is formed of two or more pairs of linear transparent electrodes 803 in parallel on the inner surface side of a first substrate 802 made of a transparent substrate such as a glass substrate, using ITO or the like. A bus electrode 807 for reducing the line resistance value is formed on the inner surface of the linear transparent electrode 803. A dielectric layer 808 that covers the transparent electrode 803 and the bus electrode 807 is formed on the entire inner surface area of the front plate, and an MgO layer 809 that is a protective layer is formed on the entire surface area of the dielectric layer 808.

  On the other hand, on the inner surface side of the second substrate 804 of the back plate 801, a plurality of linear address electrodes 805 orthogonal to the linear transparent electrodes 803 of the front plate 800 are formed in parallel by a silver material or the like. A dielectric layer 810 that covers the address electrodes 805 is formed on the entire inner surface of the back plate. On the dielectric layer 810, each address electrode 805 is isolated, and a barrier rib (partition) 806 having a predetermined height is interposed between the address electrodes in order to keep the gap distance between the front plate 800 and the rear plate 801 constant. Protrusively formed. With this barrier rib 806, cells 811 are formed along each address electrode, and phosphors 812 of RGB colors are sequentially formed on the inner surface thereof.

  A PDP having a cell structure includes a cell structure (not shown) having a discharge point as shown in FIG. 34 one by one in an independent cell, and a cell structure partitioned by a partition for each row. In recent years, the “independent cell system” has been attracting attention as a system that can improve the performance of the PDP. The reason is that by surrounding the cell with four barrier ribs in a waffle shape, light leakage between adjacent cells can be prevented and the area of the light emitter can be increased. As a result, the aim of the “independent cell system” is to increase the light emission efficiency and the light emission amount (brightness) and realize a high contrast image.

  The phosphor layer formed on the cell wall is generally thickened to about 10 to 40 μm in order to improve the color development. In order to form the RGB phosphor layer, each cell is filled with a phosphor coating solution and dried to remove volatile components, thereby forming a thick phosphor on the inner surface of the cell and simultaneously discharging. A space filled with sex gas is created. In order to form such a thick phosphor pattern, a coating material containing a phosphor is a high-viscosity paste-like fluid (phosphor paste) of several thousand mPas to tens of thousands mPas with a reduced amount of solvent. And conventionally applied to the substrate by screen printing or photolithography.

(2) Problems of conventional screen printing method When the conventional screen printing method is adopted, if the screen is enlarged, the stretch of the screen plate due to the tension is large, and it is difficult to align the screen printing plate with high accuracy over the entire screen. became. In addition, when the phosphor material is filled, the material is placed on the top of the partition wall, and in the case of the “independent cell”, there is a problem that leads to crosstalk between the barrier ribs. Therefore, measures such as introducing a polishing process are required to remove the material attached to the top of the partition wall. Moreover, the filling amount of the phosphor material changes due to the difference in squeegee pressure, and the pressure adjustment is very delicate and often depends on the skill level of the operator. Therefore, it is not easy to obtain a constant filling amount in all the independent cells over the entire area of the back plate.

(3) Problems with conventional photolithography Conventional photolithography has the following problems. In this method, after the photosensitive phosphor paste is press-fitted in the cells between the ribs, only the photosensitive composition press-fitted in the predetermined cells is left by exposure and development processes. Thereafter, through a firing process, the organic matter in the photosensitive composition is eliminated to form a phosphor layer pattern. In this construction method, since the paste used contains phosphor powder, the sensitivity to ultraviolet rays is low, and it is difficult to make the thickness of the phosphor layer 10 μm or more. Therefore, there is a problem that sufficient luminance cannot be obtained.

  In addition, when adopting photolithography, an exposure and development process is essential for each color, but since the phosphor is contained in a high concentration in the paste coating layer, the loss of the phosphor due to development removal is large, Since the effective utilization rate of the phosphor is limited to less than 30%, there is a significant problem in terms of cost.

[2] Issues in direct patterning of phosphor layers using conventional dispenser technology To achieve the independent cell method of phosphor layers by direct patterning, the issues of dispensers can be summarized as follows:
(1) Thousands to tens of thousands of mPa.s Suitable for high viscosity fluids of S (cps) order.

  (2) Even with a coating material containing a powder diameter of several μm or more, clogging does not occur in the dispenser internal flow path.

  (3) Intermittent application can be performed with a short period of msec order or less.

  (4) The coating fluid can fly at a distance of 0.5 to 1.0 mm or more from the discharge nozzle.

  (5) The coating amount per dot can be ensured with high accuracy.

  (6) Multi-heading is easy and the structure is simple.

  The above (1) to (6) are also necessary conditions for the new method to replace the conventional screen printing method and photolithography method. Hereinafter, the reason why the above (1) to (6) are necessary conditions will be supplemented a little.

  The reason why the above (1) is required is that, as described above, the coating material containing the phosphor is a solvent in order to thicken the phosphor layer of about 10 to 40 μm on the rib wall surface after coating and drying. This is because it is necessary to use a paste-like fluid having a high viscosity with a reduced amount of the above. The reason why the above (2) is required is that, as described above, in order for the display to obtain high luminance, phosphor fine particles having a particle size of several microns are usually optimal.

The reason why the above (3) is required is as follows. For example, in the case of a 42-inch wide PDP, the number of pixels is 852 in the vertical direction and 480 in the horizontal direction = 408960, and one pixel is composed of the dot trio of the three primary colors of RGB. It is a piece. Assuming that the time allowed for the phosphor coating process is T _P = 30 sec and 100 nozzles are mounted on the coating apparatus, the time per shot T _S = 30 × 100 / 1230,000 = 0.0024 sec. This value is 1/50 or less of the responsiveness of the conventional air type and thread groove type dispenser. Therefore, when considering mass productivity, a quick response dispenser far exceeding the conventional type is required.

  The reason why the above (4) is required for forming the phosphor layer by direct patterning is to prevent contact between the phosphor meniscus raised above the barrier rib apex and the tip of the discharge nozzle in the middle of application. Because.

  The reason why the above (5) is required is that the accuracy of the phosphor filling amount in the independent rib is required, for example, about ± 5%.

  The reason why the above (6) is required is that in the case of direct patterning, it is necessary to mount at least several tens of heads on the coating apparatus. In order to be able to replace the conventional construction method, maintenance performance comparable to the screen printing method and the photolithography method is required.

  Hereinafter, “air nozzle type”, “ink jet type”, and “electric field jet type” are taken up as conventional dispensers, and their applicability is evaluated.

1) In the case of an air nozzle type dispenser Conventionally, attempts have been made to continuously apply to an image tube using an air nozzle type dispenser (FIG. 31) widely used in the field of circuit mounting and the like. The air-type dispenser has a drawback of poor response. This drawback is due to the compressibility of the air confined in the cylinder and the nozzle resistance when the air passes through a narrow gap. That is, in the case of the air method, the time constant of the fluid circuit formed by the volume of the cylinder and the nozzle resistance is large, and after applying the input pulse, until the fluid starts to be discharged and transferred onto the substrate, 0.07 to 0.1 You must expect a time delay of about a second.

  Therefore, in the case of the air method, the condition that the intermittent application of the above (3) can be applied with a short cycle of msec order or less is not satisfied. In addition, since the generated pressure is limited in the air method, it is difficult to realize the condition that the coating fluid (4) can fly over a long distance.

2) Inkjet method In the case of the inkjet method shown in FIG. 32, it has a high response of 0.1 msec or less, and the fluid is ejected from the nozzle and intermittently applied while the distance between the nozzle and the facing surface is sufficiently separated. Therefore, the above conditions (3) and (4) can be satisfied. In addition, it is expected that the condition (6) that the multi-head configuration is easy and the structure is simple can be satisfied.

  However, in this method, the viscosity of the fluid is 10 to 50 mPa.s due to the driving method and structural limitations. s is the limit and cannot be used for high viscosity fluids. Further, the particle size of the powder contained in the fluid is limited to about 0.1 μm from the viewpoint of clogging, and therefore the conditions (1) and (2) cannot be satisfied. In order to draw a fine pattern using an inkjet method, a low-viscosity nanopaste in which particles having an average particle size of about 5 nm are covered with a dispersant and independently dispersed has been developed. It is assumed that a phosphor layer is formed on the inner wall of the barrier rib (partition wall) of the “independent cell” of the above-described PDP using this nanopaste. However, in the process of drying after filling the phosphor coating liquid in each cell, as described above, in order to thicken the phosphor layer of about 10 to 40 μm originally, the coating containing the phosphor The material used is a pasty fluid with a high viscosity and a reduced amount of solvent. A low-viscosity nanopaste that can only have a low phosphor content cannot form a phosphor layer having a predetermined thickness because the absolute amount of the phosphor is insufficient.

  In addition, phosphor particles with a particle size on the order of several microns are usually optimal for obtaining high brightness, so the phosphor particle size cannot be easily changed at this stage. It is.

3) Case of Electric Field Jet Method The electric field jet method shown in FIG. 33 has the following problems. In the case of the electric field jet method, the fluid at the tip of the discharge nozzle is subjected to an electric field and receives a force flowing toward the substrate.

The electric field applied between the tip of the discharge nozzle and the counter substrate is turned on and off, and the continuous flow connected to the inside from the tip of the nozzle is cut off, so that intermittent discharge is possible with a low flow rate and low viscosity fluid. However, when the average flow rate is large and the fluid is highly viscous, the continuous flow is not easily interrupted and intermittent discharge becomes difficult. For example, assuming that the volume of the PDP independent cell is V = 0.65 mm (vertical) × 0.25 mm (horizontal) × 0.12 mm (depth) ≈0.02 mm ³ , the time T _S = 0.002 sec per shot Then, the average flow rate Q = 0.02 / 0.002 = 10 mm ³ / sec. This flow rate value exceeds the limit at which the electric field can be controlled at high speed. Further, when both an electric field and air pressure are applied to secure the flow rate, high-speed intermittent application becomes difficult due to the poor air-type response described above. Therefore, the electric field jet method cannot satisfy the above (3).

  Summarizing the above considerations, a method having a possibility of replacing the screen printing method and the photolithography method, for example, a direct patterning method for realizing the formation of an independent cell phosphor layer of PDP cannot be found at this stage.

  Hereinafter, the past proposal concerning the intermittent application dispenser of the present inventor will be described a little. In order to meet various recent demands related to micro flow rate application, the present inventor in Japanese Patent Application No. 2000-188899 gives a relative linear motion and a rotational motion between a piston and a cylinder, as well as a rotational motion. Has proposed a coating method that provides a means for transporting fluid, changes the relative gap between the fixed side and the rotating side using linear motion, and controls the discharge amount.

  In the above proposal, a thrust dynamic pressure seal is formed on the relative movement surface of the discharge-side end surface of the piston and its opposing surface, and the fluid is controlled to be shut off by the dynamic pressure sealing effect when the gap between the opposing surfaces is narrowed. .

  Japanese Patent Application No. 2000-208072 proposes a dispenser in which a positive displacement pump is configured by independently driving a piston and a cylinder storing the piston using two independent linear motion means. Yes.

  Further, a theoretical analysis is performed on the dispenser structure disclosed in the specification of Japanese Patent Application No. 2000-188899, and intermittent discharge using a squeeze pressure generated by abruptly changing the gap between the piston end surface and its relative movement surface. A method and apparatus are being proposed (Japanese Patent Application No. 2001-110945). This squeeze pressure is known as the hydrodynamic effect of a fluid bearing. In order to use this squeeze pressure, the gap between the piston end surface and its opposing surface is narrow, for example, 20-30 μm or less. Must be set.

  In the specification of Japanese Patent Application No. 2002-286741, as a result of further theoretical analysis, even when the gap between the piston end surface and its opposing surface is sufficiently wide, the squeeze effect is equivalent by utilizing the internal resistance of the thread groove pump. It has been found that the above high generated pressure, that is, the secondary squeeze pressure can be obtained. If this secondary squeeze pressure is used, the management of the gap between the piston end faces may be simple, the structure is simple, and the total discharge amount per dot can be set by, for example, the rotational speed of the fluid supply pump. Therefore, practical handling is easy, flow rate accuracy per dot is high, ultra-high-speed intermittent application on the order of several milliseconds is possible, and an ultra-small amount of application device with high reliability against powdered fluids Can be realized.

  Even if the inventor's previously proposed dispenser can sufficiently satisfy the above (1) to (6) that can replace the conventional screen printing method and photolithography method, it is highly reliable at the mass production stage. There were still many issues to ensure. The reason is that even if the fluid pressure generated in the pump chamber of the dispenser and the flow rate passing through the nozzle can be controlled on the dispenser side, the fluid behavior after flying from the nozzle cannot be controlled.

  In FIG. 35, a process in which a dispenser having a multi-nozzle moves relative to the PDP back plate 801 and implants phosphors into independent cells formed geometrically symmetrical like a grid. Is assumed.

Now, in the development process of the coating apparatus in which the present invention is found, the following has been clarified from the result of detailed observation of the coating fluid flying from the nozzle by a high-speed camera. Reference numeral 850 denotes a dispenser, 851 denotes a discharge nozzle, and 852 denotes an independent cell covered with a rib. FIGS. 30A to 30D are model diagrams showing the behavior of the fluid flying from the discharge nozzle 851 observed by the high-speed camera under the condition of the intermittent period T = 2 msce and the stage speed V _S = 300 msec. Reference numeral 853 denotes a lateral rib. The lateral rib positioned on the front side with respect to the travel position of the discharge nozzle 851 is defined as a front lateral rib 853F, and the lateral rib positioned on the rear side is defined as a rear lateral rib 853R.

FIG. 30A shows a state immediately after the start of discharge, and at this time, the center position of the discharge nozzle 851 is close to the rear side lateral rib 853R. The meniscus of the coating fluid to which the pulsed pressure waveform is given in the pump chamber of the dispenser becomes a tapered shape 854 immediately after the start of discharge due to the action of surface tension. FIG. 30B shows a case where the center position of the discharge nozzle is at the center of the independent cell. FIG. 30C shows a state immediately after the end of the discharge stroke when the center position of the discharge nozzle 851 approaches the front side lateral rib 853F. Since the pressure in the pump chamber becomes negative, a part of the stream line 855 on the discharge nozzle side is again sucked into the nozzle as indicated by the arrow. Therefore, the coating continuous line is separated and cut at a part 856 and a part 857 of the stream line that is descending to the substrate side. FIG. 30D is a stage where the center position of the discharge nozzle 851 is on the front lateral rib 853F, and the fluid 855 in the vicinity of the discharge nozzle is almost sucked into the nozzle. However, the portion 856 of the stream line descending toward the substrate side has a speed component of the discharge nozzle-to-substrate moving speed V _S , and thus lands so as to cover the front side lateral rib 853F.

The state in which the continuous application fluid is cut depends on the spinnability, which is a characteristic characteristic of the material as a rheological fluid, the outer diameter of the continuous coating line, the movement speed V _S between the discharge nozzle and the substrate, etc. Dominated by. The trouble caused by this spinnability cannot be ignored in phosphor pastes that use high-molecular materials and low-molecular materials as solvents. Therefore, in the process of applying a phosphor to an independent cell using a dispenser, a measure for preventing the coating line from covering the rib is an inevitable problem.

  The present invention provides a versatile solution that is fundamental and versatile with respect to the problems described above. That is, a boundary electrode is provided in advance at the boundary of the coating pattern to be formed, and a voltage having the same sign as the charge applied to the coating material is applied to the boundary electrode, so that the coating material converges only within the boundary. Is a function of For example, when the application target is a plasma display panel, the present invention can be applied by utilizing the unique structure of the back plate.

  That is, a rib apex electrode that also serves to prevent crosstalk is formed on the top of a barrier rib that surrounds the cell in a waffle shape, and a positive voltage is applied to the rib apex electrode, for example, and the address arranged on the lower surface of the cell to be coated A negative voltage is applied to the electrode. In this state, the phosphor paste charged with a positive charge is continuously discharged toward the target independent cell, so that the phosphor paste applied toward the vicinity of the target independent cell is aligned along the direction of the electric field. Move to converge inside independent cells. That is, the trajectory of the paste flying over the vicinity of the ribs covering the space between the two independent cells is corrected by the action of the electric field, and the ride to the top of the ribs is avoided. As a result, an extremely reliable method of forming an independent cell phosphor layer of PDP can be realized.

  In the first coating method of the present invention, a coating material is charged to a charge having a predetermined sign in a state where an electrode is previously formed in the vicinity of a boundary portion of a coating pattern to be formed on a substrate, and the charge is applied to the electrode. The coating pattern is formed by supplying the coating material toward the substrate in a state where the same voltage is applied.

  Further, the second coating apparatus of the present invention includes a substrate to be coated, a boundary portion of a pattern to be coated formed on the surface of the substrate or in the vicinity of the thickness direction of the substrate, and an electrode disposed in the vicinity of the boundary portion. A pattern to be applied by supplying the coating material toward the substrate in a state in which the coating material is charged to a charge having a predetermined sign and a voltage having the same sign as the charge is applied to the electrode. Is formed.

  The following effects can be obtained by the dielectric discharge method using the present invention.

(1) Regardless of the type of coating material such as high viscosity fluid, low viscosity fluid, powder, powder fluid,
A highly accurate fine pattern can be formed.

  (2) The structure of the coating device can be simplified.

  (3) High reliability.

  For example, if the present invention is used for phosphor coating of PDP, CRT display, electrode formation, circuit formation, microlens formation, etc., the advantages can be fully exhibited, and the effect is tremendous.

  Hereinafter, the present invention will be described in the following cases.

[1] Independent cell phosphor layer forming method of PDP [2] Application to other construction methods First, the above [1] will be described.

  FIG. 1 is a model diagram showing a first embodiment of the present invention. Assumes a process in which a multi-nozzle dispenser moves relative to the base while the phosphor is driven by continuous coating into a PDP independent cell that is geometrically symmetrical like a grid. doing. The phosphor paste continuously flowing out from the discharge nozzle is corrected in its trajectory by the action of an electric field in the vicinity of the independent cell, and is landed and filled only inside the cell without riding on the top of the rib.

  Although details will be described later, a rib top electrode is formed at the apex of the barrier rib forming the independent cell (boundary portion of the coating pattern), and an electric field is formed between the rib top electrode and the address electrode. Yes. That is, while the dispenser side is continuously ejected, an apparent super-high-speed intermittent application (pseudo-intermittent application) can be realized on the substrate side where the paste lands by the action of an electric field.

  In the first embodiment, an electric field is formed between the rib top electrode and the address electrode so that the fluid flying from the discharge nozzle steadily enters only one independent cell.

  In FIG. 1, 1 is the entire back plate, 2 is the main body of the dispenser, and 3 is the discharge nozzle. The dispenser that has traveled on the substrate in the direction of the arrow 4 while driving the phosphor of the same color into the independent cell makes a U-turn as indicated by the arrow 5 at the end of the substrate, and repeats the same operation to finish the application of each color of RGB. Repeat until.

  FIG. 2 is a partially enlarged model diagram of FIG.

  3 is an enlarged top view of a part of the back plate 1, FIG. 4 is a front sectional view, and FIG. 5 is a side sectional view. Reference numeral 6 denotes an independent cell, which is composed of a triple set of 6R, 6G, and 6B.

  Reference numeral 7 denotes a second substrate, and reference numeral 8 denotes an address electrode, which is similarly composed of a triple set (indicated by a chain line) of 8R, 8G, and 8B. Reference numeral 9 denotes a vertical rib constituting the barrier rib, and reference numeral 10 denotes a horizontal rib. The horizontal rib positioned on the front side with respect to the travel position of the discharge nozzle is the front side horizontal rib 10F, and the horizontal rib positioned on the rear side is the rear side horizontal rib. It will be called 10R.

  3 and 5 indicate the traveling direction of the discharge nozzle. Reference numeral 11 denotes a dielectric layer that covers the address electrodes 8 and is formed with vertical ribs 9 and horizontal ribs 10. 12 is a rib top electrode formed at the apex of the vertical rib 10 and the horizontal rib 11, and 13 is a coating fluid (shown in FIG. 5). Here, attention is paid to the independent cell 6G, which is a space to be coated for the time being covered with the vertical ribs 10 and the horizontal ribs 11. FIG. 3 shows a state where the discharge nozzle 3 is located at the center of the independent cell 6G. In the present invention, an electric field is formed between the address electrode 8 and the rib top electrode 12, and a charge having a predetermined sign is given to the coating fluid in advance, so that the fluid discharged from the discharge nozzle 3 is placed in the independent cell. It can be filled with high accuracy.

  For example, a positive potential is applied to the rib top electrode 12, the address electrode 8 is set to zero potential (ground), and a positive charge is applied to the coating fluid 13. As a result, an electric force line is formed between the rib top electrode 12 and the address electrode 8, and the coating fluid 13 having a positive charge moves along the direction of the electric force line. It is filled in the independent cell.

Hereinafter, the principle and effect of the present invention will be described in more detail using the results of electric field analysis. FIG. 6 shows analysis conditions for electric field analysis. Focusing on the vicinity of one independent cell 6G, the voltage V _A = OV is applied to the address electrode 8G, and the voltage V _R = 100 V is applied to the rib top electrode 12. The relative dielectric constant ε = 1 of air, the rib thickness is 0.035 mm, the rib height is 0.12 mm, and the distance between the inner walls of the front side rib 10F and the rear side rib 10R is 0.65 mm.

  7A shows the analysis result of the voltage distribution, and FIG. 7B shows the analysis result of the electric field distribution.

  The electric field strength varies greatly depending on the location. The electric field strength E = 158 V / m at the upper position 1) away from the rib, and E at the intermediate position 2) between the front side rib 10F and the rear side rib 10R inside the independent cell. = 15.1 million V / m, in the vicinity of the rib wall surface 3), E = 648,000 V / m, and in the vicinity of the rib top electrode 12 4), E = 1.08 million V / m.

  Accordingly, it can be seen that the portion where the strongest electric field is generated is in the vicinity of the rib top electrode 12, and the influence of the charged fluid from the electric field is greatest in the vicinity of the rib top electrode.

  FIG. 8A shows the electric field vector analysis result, and FIG. 8B shows the electric field vector inside the dielectric layer including the rib. The direction of the electric field line vector indicates the direction of the force received by the positive charge, and the magnitude of the vector indicates the magnitude of the force received by the unit charge.

  As can be seen from the result of FIG. 8A, when attention is paid to one rib (for example, the front side lateral rib 10F), the electric lines of force generated from the rib top electrode 12 are divided into two hands at the upper part of the rib top electrode 12. It turns in the direction of 180 degrees and enters the address electrodes 8G arranged on the left and right independent cell bottom surfaces, respectively. Therefore, the phosphor paste that should originally land on the top of the rib is orbitally corrected so as to follow the direction of the electric field vector above the rib top electrode 12, and the address electrode (ie, the bottom surface of the independent cell) is given a negative voltage. ).

Therefore, if the relative speed between the discharge nozzle and the back plate is constant and the continuous flow rate flowing out from the discharge nozzle is constant, the flow rate of the phosphor paste that should have landed on the top of the rib is distributed to the left and right, The independent cell is filled with a paste having a predetermined total flow rate. According to this construction method, pseudo intermittent application is possible without using an intermittent dispenser that requires a high-speed response, so the performance specifications required for the dispenser are greatly reduced.
In this embodiment, a voltage having a different sign from that of the rib top electrode is applied to the address electrode. Although the effect is reduced, it is possible to obtain the effect of preventing the climbing to the rib top only with the rib top electrode alone. The reason is that an electric field is still formed between the rib top electrode and infinity, and in this case also, the electric field strength at the rib top is maximized. Therefore, a voltage having the same sign as that of the coating material may be applied only to the rib top electrode, depending on the constraints of the process to be applied.

  The second embodiment of the present invention will be described below.

  In the first embodiment described above, an electric field is formed between the address electrode and the rib top electrode arranged on the bottom surface of the independent cell to be coated. In the second embodiment, in addition to the first embodiment, the same voltage as the charge charged in the phosphor paste is applied to the address electrodes arranged on the left and right of the application target cell in the application direction. Is applied. By this method, the phosphor paste is prevented from scattering to the cells adjacent to the left and right, and the coating reliability is further improved.

  FIG. 9 shows analysis conditions for electric field analysis.

Focusing on the vicinity of one independent cell 50G, it has independent cells 50R and 50B on the left and right. 51-1 and 51-2 are vertical ribs, and 52-1 and 52-2 are rib top electrodes formed on the respective ribs. 53R, 53G, and 53B are address electrodes formed on the bottom surface of each independent cell. Note that the dispenser and the substrate travel relatively in the vertical direction of the drawing (refer to FIGS. 3 and 4 for the positional relationship). A voltage V _AG = OV is applied to the address electrode 53G on the bottom surface of the independent cell 50G to be coated, V _AR = 200 V is applied to the left address electrode 53R, and V _AB = 200 V is applied to the right address electrode 53B. Further, the voltage V _R = 100 V is applied to the rib top electrodes 52-1 and 52-2. The relative dielectric constant ε = 1 of air, and the distance between the inner walls of both ribs (51-1 and 51-2) is 0.25 mm.

  FIG. 10 (a) shows the analysis result of the electric field vector, and FIG. 10 (b) is a partially enlarged view thereof. An electric field is formed by the voltages applied to the left and right address electrodes 53R and 53B, the rib top electrodes 52-1 and 52-2, and the central address electrode 53G. That is, electric field lines that enter the central independent cell from the left and right address electrodes 53R and 53B through the dielectric ribs and electric field lines that rise toward the rib top electrode are generated. In either case, the direction changes on the central address electrode 53G and is attracted to the address electrode 53G. Accordingly, even when a dielectric material having a positive charge jumps over the left and right independent cells 50R and 50B according to the present configuration, the trajectory correction by the electric field works and only the predetermined independent cell 50G is filled with the coating material.

  The third embodiment of the present invention will be described below. The embodiment described above was a method of forming an electric field only between electrodes on a substrate. In the following embodiment, a case is shown in which not only a voltage is applied to each electrode on the substrate but also an electric field is formed between the substrate and the discharge nozzle by applying a voltage to the discharge nozzle.

FIG. 11 shows the analysis result of the electric field vector, and shows the position where the discharge nozzle is arranged in the figure. Reference numeral 300 denotes an independent cell, 301F denotes a front side lateral rib, 301R denotes a rear side lateral rib, and 302 denotes a discharge nozzle (indicated by a two-dot chain line). The analysis conditions are voltage V _A = OV for the address electrode arranged on the bottom surface of the independent cell 300, voltage V _R = 100V for the rib top electrode, and electrode V _N = 200V arranged for the discharge nozzle. As in the first embodiment, the rib shape is 0.035 mm, the rib height is 0.12 mm, and the distance between the inner walls of the front side rib 301F and the rear side rib 301R is 0.65 mm. .

  As can be seen from comparison with FIG. 8 (a), which is the first embodiment in which the electric field is formed only on the substrate side, in this embodiment, the charged fluid is generated from a position sufficiently higher than the top of the rib. to be influenced. That is, in this embodiment, it can be seen that the “trajectory correction section” necessary for condensing the fluid flowing out from the discharge nozzle 302 only in a predetermined independent cell can be made sufficiently long.

  FIG. 12 shows the analysis result of the electric field strength distribution. The electric field strength E = 18.2 thousand V / m at the upper position 1) away from the rib, and E = 27.8 at the intermediate position 2) of the front side rib 10F and the rear side rib 10R inside the independent cell. 10,000 V / m, near rib wall surface 3) E = 651,000 V / m, near rib top electrode 301F 4) E = 875,000 V / m 2, middle portion 5 of discharge nozzle 302 and independent cell 5) Then, E = 17.1 million V / m. Therefore, it can be seen that a sufficiently large electric field is formed in the entire section from the discharge nozzle 302 to the independent cell 300.

  As described above, the rib top electrode used in the first to third embodiments of the present invention plays an extremely important role in the “PDP independent cell phosphor layer forming method”. The rib top electrode is extremely useful as a means for improving the performance of the display for the following reasons.

  Conventionally, 1) Reduce erroneous discharge due to crosstalk to cells that are not subject to discharge relative to cells that are subject to discharge, 1) Ensure brightness and exhaust characteristics, and satisfy both 1) and 2) above In order to achieve this, a complicated rib shape was required.

  When a predetermined voltage is applied to the rib top electrode when the PDP is actually operated, the shortage of electric charges inside the cell is compensated for and the constant potential is maintained, thereby electrically shielding the ribs and crosstalk. Therefore, a high-contrast image can be realized.

  Also, when the PDP is used in high altitudes (low pressure areas), or when used in a high temperature / low temperature environment, the ribs expand and contract due to temperature changes, and the gap between the rib top and the opposite surface changes partially. The effects of reducing the occurrence of crosstalk can be obtained.

Therefore,
(1) In the manufacturing process of the PDP, by electric field control using the rib top electrode,
Realizes extremely high-quality phosphor coating. Moreover, since the coating device can be simplified, the manufacturing cost is also reduced.

  (2) A high contrast image is realized by the rib top electrode.

  If the rib top electrode is used in the manufacturing process, the merit (1) can be obtained, and the synergistic effect (2) can be obtained.

  The rib electrode formed to cause an apparent “water-repellent effect” by an electric field to the coating material is not necessarily provided at the apex of the rib.

  FIG. 13A shows a case where a rib electrode is formed in the middle part of the rib. 900 is an independent cell, 901 is a second substrate, 902 is an address electrode, 903 is a rib, and 904 is a rib electrode. FIG. 13B shows a case where a rib electrode is formed below the rib. 910 is an independent cell, 911 is a second substrate, 912 is an address electrode, 913 is a rib, and 914 is a rib electrode.

  If a dielectric is used for the rib, a sufficiently large electric field strength can be obtained at the top of the rib in any of the above (1) and (2). Further, when a conductive material is used for the entire rib, the present invention can be applied using the entire rib as an electrode.

In addition, in the case of forming an electrode at the apex of the rib, or when forming at other than the apex, in any case, if water repellent treatment is performed in advance using an organic thin film process or the like at the position located at the rib apex, 1)
The combination of the apparent water repellency effect by the electric field + 2) the water repellency effect by the chemical treatment further enhances the measures for preventing the phosphor from climbing onto the top of the rib.

  Further, as is common to the above-described embodiments, the timing of applying a voltage to the rib top electrode and the address electrode may be during application or after completion of application if the application material is charged to a predetermined charge. . Since the coating material is not easily neutralized, the material attached to the top of the rib can flow down into the cell away from the top of the rib.

  The fourth embodiment of the present invention will be described below. In any of the above-described embodiments, when the charged fluid that should enter the target independent cell leaves the original trajectory, the trajectory is corrected by the action of the electric field.

Here, if the sign of the electric field at the top of the rib is made the same as the sign of the charged fluid and the electric field strength at the top of the rib can be made larger than that of the other space, the electric field in the direction to prevent the coating material from sticking to the top of the rib. Note that works. For example, the rib top electrode is omitted, a positive voltage V _A is applied to the address electrode, and a voltage V _N <V _A is applied to the discharge nozzle. Using the fact that the barrier rib used in the PDP is a dielectric, the vicinity of the top of the rib has the highest electric field strength compared to other spaces.

  In this case, the direction of the electric field vector is directed from the substrate side to the discharge nozzle side, contrary to the case of the third embodiment. In other words, the positively charged dielectric is decelerated by the action of the electric field after flowing out of the discharge nozzle. For example, the following effects can be obtained by applying the idea of this embodiment to the ultra-high-speed intermittent application dispenser proposed by the inventor in Japanese Patent Application No. 2002-286741.

  1) Since the coating material having a charge of a predetermined sign flies away from the vicinity of the rib top having the highest electric field strength, it is possible to prevent the coating material from climbing onto the rib top.

  2) Since the coating material that has flowed out of the discharge nozzle at a high speed is decelerated by the action of an electric field in the middle, it is possible to reduce the ride on the top of the rib due to rebounding when landing on the bottom surface of the independent cell.

  That is, the highly reliable phosphor coating on the independent rib can be realized by the synergistic effects of 1) and 2).

  FIG. 14 is a model diagram of the present embodiment, 350 is an independent cell, 351 is a second substrate, 352 is an address electrode, 352 is a discharge nozzle, and 354F is a front side located on the front side with respect to the travel position of the discharge nozzle. The lateral rib 354R is a rear lateral rib located on the rear side, and 355 is a dielectric layer on which the rib is formed. Reference numeral 356 denotes a coating fluid in flight at a speed U.

FIG. 15 shows the analysis result of the electric field vector, and shows the position where the discharge nozzle is arranged in the figure. The analysis condition is that the voltage V _A = 150 V is applied to the address electrode 352 arranged on the bottom surface of the independent cell 350 and the electrode V _N = 100 V is arranged on the discharge nozzle 353. As in the first embodiment, the rib shape is 0.035 mm, the rib height is 0.12 mm, and the distance between the inner walls of the front side rib 354F and the rear side rib 354R is 0.65 mm. .

  FIG. 16 shows the analysis result of the electric field strength distribution. Electric field strength E = 100,000 V / m at position 1) near the discharge nozzle, E = 99,000 V / m at position 2) above the middle portion of the independent cell 350, and E = at the top 3) of rib 301F. 130,000 V / m. Therefore, the electric field strength near the top of the rib is the highest.

In this embodiment, the positively charged fluid is a force f (in FIG. 14) that moves from the substrate side to the discharge nozzle side as indicated by the direction of the electric field vector in FIG. Receive). As a result, if the flow velocity of the fluid immediately after flowing out from the discharge nozzle 353 is U = U ₀ , the flying fluid is subsequently decelerated by the action of an electric field as shown in FIG. If the flow velocity at the time of landing in the independent cell interior 350 is U = U _E , if the conditions can be set so that U _E > 0 at this stage, the fluid is safely filled in the independent cell. If the purpose is only to prevent the flying fluid from decelerating and to prevent the coating material from running onto the top of the rib, it is not necessary to apply a voltage to the discharge nozzle.
Incidentally, the voltage applied to the discharge nozzle side V _N, when the voltage applied to the substrate side is a coating object was set to V _A, an electric field is formed as a V _N <V _A, decelerating the charged material flying from the discharge nozzle Thus, the method for suppressing the rebound of the material landing on the substrate at a high speed can of course be applied to a coating method other than the PDP rib formation. The coating material is not limited to fluid, but may be toner (powder), for example.

  17 shows the structure of a multi-head dispenser body to which the present invention is applied. FIG. 17 (a) is a top view and FIG. 17 (b) is a front view.

  In FIG. 17, reference numeral 401 denotes a main shaft that is housed so as to be movable in the rotational direction with respect to the housing 402. The main shaft 401 is rotationally driven by a motor 403 (not shown) that is a rotation transmitting means. Reference numeral 404 denotes a thread groove formed on the relative movement surface of the main shaft 401 and the housing 402, reference numeral 405 denotes a fluid suction port, reference numeral 406 denotes a syringe for storing the coating material 407, and reference numeral 408 denotes an air pipe for supplying auxiliary air pressure.

  409 is a piston, 410 is a piezoelectric actuator which is an axial driving means for moving the piston 409 in the axial direction, 411 is a bottom plate, and 412 is a flow passage formed between the housing 402 and the bottom plate 411. Reference numeral 413 denotes a discharge nozzle mounted on the bottom plate 411.

  Reference numeral 414 denotes a small diameter portion of the syringe 406, reference numeral 415 denotes an electrode provided on the small diameter portion 414, reference numeral 416 denotes a power supply section, and reference numeral 417 denotes a control section. A charge having a predetermined sign is given to the coating material 407 by a voltage applied to the electrode 415 provided on the syringe small diameter portion 414. The coating material 407 is supplied from the discharge nozzle 413 after being supplied to the thread groove pump unit.

  As shown in the third embodiment, when an electric field is positively formed between the discharge nozzle and the substrate, an electrode may be provided on the discharge nozzle.

  As described above, even when a continuous application dispenser is used according to the method of the present invention, it is possible to avoid attaching the phosphor to the top of the rib, and to fill the phosphor only in the independent cell. However, when the high-speed intermittent application method is combined with the present invention, the countermeasure for attaching the phosphor to the top of the rib becomes more thorough. In order to realize intermittent application, it is necessary to generate a positive pressure having a sharp peak upstream of the discharge nozzle of the dispenser, and to generate a negative pressure immediately thereafter. This is because it is necessary to separate and block the fluid that has flowed out of the discharge nozzle immediately after discharge and the fluid on the discharge nozzle side.

  In general, intermittent application requires a high-speed response to an actuator that drives a dispenser as compared to continuous application, and the mechanism system and control system are complicated.

  18 and 19 show that by applying the present invention, pseudo intermittent application can be realized even if the material is discharged in a continuous flow with periodic pulsation. FIG. 18 is a displacement curve of the piston 409 end face clearance when the above-described dispenser (FIG. 17) is used.

  19A is a discharge pressure waveform, FIG. 19B is a discharge nozzle that runs on a rib, 750 is an independent cell, 751 is a second substrate, 752 is an address electrode, and 753. Is a front side rib, 754 is a rear side rib, 755 is a rib top electrode, 756 is a phosphor paste, and 757 is a discharge nozzle. A voltage having the same sign as the electric charge charged in the phosphor paste is applied to the rib top electrode.

  When the above-described dispenser (FIG. 17) is intermittently discharged, the secondary squeeze pressure is used, so the discharge pressure has a waveform whose phase is advanced by 90 degrees with respect to the displacement curve (FIG. 18) of the piston end face clearance. . Since the discharge flow rate = (discharge pressure / nozzle fluid resistance), the discharge flow rate has the waveform shown in FIG.

  When the discharge nozzle 757 is above the rear side rib 754, the application conditions are set so that the curve of the discharge flow rate is at the position of time A. When the discharge nozzle 757 is above the middle portion between the rear side rib 754 and the front side rib 753, the application conditions are set so that the discharge flow rate curve is at the position of time B. When the discharge nozzle 757 is above the front rib 753, the application conditions are set so that the discharge flow rate curve is at the position of time C.

  Accordingly, when the discharge nozzle 757 is above the rib top electrode 755, the flow rate of the phosphor paste 756 that is lowered becomes a minimum value, and thus it is easier to prevent the paste from climbing onto the rib top due to the action of an electric field. It becomes. Since the peak value of the coating flow rate does not have to be as sharp as in the case of intermittent coating, it is possible to avoid scattering due to rebound when the jet flows on the bottom surface of the substrate. Therefore, the reliability of the phosphor coating method for the independent cell is further improved. Since the waveform for driving the piston may be a sine wave, the response of the dispenser is not so much required as compared with the intermittent application, and the burden on the apparatus side is greatly reduced.

  As shown in FIG. 32, the barrier ribs of the PDP are as follows: 1) a type having discharge points one by one in an independent cell, and 2) a cell structure type partitioned by a partition for each row. The above-described embodiments have been described by taking as an example the case of applying to the independent cell of 1). However, the present invention can of course be applied to the stripe type of 2).

[II] Other Application Examples Hereinafter, application examples other than the dispenser of the present invention will be described.

  FIG. 20 (a) shows a state immediately after the phosphor is implanted into an independent cell of the PDP using the inkjet method, and FIG. 20 (b) shows a state after drying.

  As described above, in the case of the inkjet method, a high-viscosity fluid cannot be handled due to restrictions on the driving method and structure, and therefore, a low-viscosity nano paste in which particles having an average particle diameter of about 5 nm are dispersed is used. However, as described above, there is a problem that a phosphor layer having a predetermined thickness cannot be formed because the absolute amount of the phosphor is insufficient even when the coating liquid for phosphor is filled up to the wall surface in the gap of the independent cell. there were. Therefore, if a voltage having the same sign as the electric charge applied to the phosphor coating liquid is applied to the rib top electrode, even if the height of the phosphor liquid meniscus apex is sufficiently higher than the rib top, an apparent “repellency due to an electric field” is applied. The fact that the phosphor liquid is kept from overflowing due to the “water effect” is utilized.

  101 is an independent cell, 102 is a second substrate, 103 is an address electrode, 104 is a barrier rib, 104 is a dielectric layer covering the address electrode 103 and having a barrier rib 104 formed thereon. Reference numeral 105 denotes a rib top electrode formed at the apex of the barrier rib 104. Even if the contact angle α at the portion of the coating fluid meniscus protruding from the top of the rib is sufficiently large, the coating fluid does not overflow to the top of the rib, so that the total coating flow rate, that is, the total amount of phosphor can be sufficiently increased.

  FIG. 21 shows an application example in which a phosphor layer is formed in an independent cell of a PDP using a toner jet method. 151 is a developing roller, 152 is an intermediate roller, 153 is a stirring roller, 154 is a discharge port, 155 is an upstream ring electrode formed on the inner wall of the discharge port 154, 156 is a downstream ring electrode, and 157 is a fluorescent material that is a coating material. It is a body toner (powder). 158 is an independent cell, 159 is a second substrate, 160 is an address electrode, 161 is a barrier rib, and 162 is a rib top electrode formed at the apex of the barrier rib 161.

  The toner 157 positively charged by the intermediate roller 152 to which a voltage of about several hundred to 1 KV is applied is transported to the opening of the discharge port 154 by the negatively charged developing roller 151. An electric field is formed in advance between the rib top electrode 162 and the address electrode 160 on the bottom surface of the independent cell 158.

  The toner 157 accelerated by the two electrodes 155 and 156 to which a voltage of several hundred volts is applied and flies over the address electrode 160 is applied to the address electrode 160 to which a voltage of an opposite sign is applied to the charge of the toner 157. So as to be sucked into the independent cell 158. On the other hand, the toner 157 that has deviated from the desired trajectory and flew over the top of the barrier rib 161 has its trajectory corrected as shown by a trajectory 163 by the electric field formed between the rib top electrode 162 and the address electrode 160, and the independent cell 158. Sucked inside.

  In the case of the toner jet method, the powder flowing out from the discharge port 154 cannot always land at the target point due to the repulsion between the flying powder having the same charge, and there is a weak point that it is applied with some scattering. It was. By using the method of the present invention, the trajectory is corrected by the action of the electric field, including the powder deviating from the trajectory that should be in flight or the powder resurfaced by rebounding with the substrate after landing, and the target point is steadily Can land on.

  In this application example, the phosphor layer is formed in the independent cell of the PDP. However, an electrode is provided near the boundary of the coating pattern formed on the substrate, and the same sign as the charge applied to the coating material. Of course, the idea of applying a voltage of 2 to the electrode can be applied to other materials and processes.

  FIG. 22 shows a case where the present invention is applied to a method of forming a functional thin film on a thin organic film. Here, the functional thin film is a thin film having an electrically, physically, and chemically effective function. For example, the electrical performance (dielectric constant, electrical property, etc.) necessary for realizing device functions such as a coil, a resistor, and a capacitor. 1 shows a thin film having a resistivity. Reference numeral 200 denotes an organic film as a substrate, 201 denotes a base material A formed from a non-conductive material, and 202 denotes a base material B formed from a conductive material. The organic film 200 used as the sheet device is made of polyimide having a thickness of about 50 to 60 μm.

  203a and 203b are boundary electrodes formed on the base material A201, and 204 is a master pattern made of a dielectric formed between the two boundary electrodes. A voltage having a plus sign is applied to the boundary electrodes 203a and 203b, and the base material B202 is grounded (voltage is zero). As a result, an electric field is generated by the lines of electric force having the direction indicated by the arrow 205.

  Reference numeral 206 denotes a discharge port of the coating apparatus, and the coating material 207 discharged from the discharge port 206 is charged with a charge having the same sign as the boundary electrodes 203a and 203b. 23A and 23B show a state in which the boundary electrodes 203a and 203b and the master pattern 204 made of a dielectric are formed on the base material A201.

  FIGS. 24A and 24B show a state in which a target coating pattern 209 is drawn on the organic film 200 as a substrate in a state where the base material B202, the base material A201, and the organic film 200 are overlapped.

  In FIG. 22, the coating material that has jumped from the ejection port 206 toward the substrate 200 undergoes trajectory correction so as to avoid the upper portions of the boundary electrodes 203 a and 203 b, and lands between the two boundary electrodes. The electric lines of force 205 that pass through the inside of the coating material 207 have a centripetal direction component, and thus act in a direction that increases the surface tension between the substrate 200 and the coating material 207. As a result, the coating material 207 is applied only to the upper part of the master pattern 204 located in the gap between the boundary electrodes 203a and 203b. In summary, with respect to the charge of a predetermined sign applied to the coating material 207 flowing out from the discharge nozzle, the voltage of the same sign 203a and 203b is applied to the boundary electrode, and the base material B202 which is a conductive material is grounded (voltage). May be zero) or a voltage with a different sign may be applied.

  In this construction method, a coating line having a width smaller than the inner diameter of the discharge nozzle 206 and smaller than the diameter of the stream line flowing out from the discharge nozzle can be drawn. The coating pattern can be formed in any shape including stripes and dots. In this embodiment, since the electric field is formed only on the substrate side, the formed electric field can be maintained even if the discharge nozzle 206 is moved away from the substrate side (configured from the members 200, 201, 202). The shape of is maintained.

  FIG. 25 shows a case where a master pattern is formed by making the boundary electrode a thin plate instead of a drawing line and punching this plate. 450 is an electrode plate, 451 is a master pattern that penetrates the electrode plate, and a dielectric 452 is enclosed in the slit portion, and 453 is used for vacuum suction of the organic film when forming a coating pattern on the organic film. It is a distribution hole.

  In FIG. 26, reference numeral 454 denotes a coating pattern applied on an organic film, reference numeral 455 denotes an organic film, reference numeral 456 denotes a base material A formed from a non-conductive material, and reference numeral 457 denotes a base material B formed from a conductive material.

  FIG. 27 shows the case where the boundary electrode is omitted by forming an electric field between the discharge nozzle side and the substrate, and only the master pattern is formed on the base material.

  In FIG. 27, 975 is an organic film, 976 is a non-conductive material base material C, 977 is a master pattern formed of a conductive material, 978 is a coating pattern formed on the organic film, and 979 is a discharge nozzle. . A positive voltage is applied to the discharge nozzle 979, and a ground voltage or a voltage with a different sign is applied to the master pattern 977. As a result, an electric field is generated between the discharge nozzle 979 and the substrate by electric lines of force having the direction indicated by the arrow 980. As a result, a fine line or a small dot can be formed by the water repellent effect due to the electric field between the substrate 975 and the coating pattern 978. A conductive material may be used for the base material C976, and the master pattern 977 may be formed of a dielectric material of a nonconductive material.

  As described above, as a method of forming a master pattern, 1) a method of drawing a drawing line of a dielectric material on a non-conductive material (base material A), and 2) penetrating an electrode plate into a predetermined shape A method of encapsulating a dielectric in a slit portion that penetrated and 3) a method of forming a drawing line using a conductive material as a non-conductive material (base material C) have been described. The combination of these members or electric field formation may be any method, and the point of interest of the present invention is that when the substrate to be coated (for example, an organic film) is thin, the boundary electrode may not be formed directly on the substrate. By providing a master pattern or boundary electrode directly under the substrate, an electric field that gives an apparent “water-repellent effect” to the coating material can be used.

  The master pattern and the boundary electrode can be formed by any method, and screen printing, photolithography, dry etching, or a dispenser can be applied. The non-conductive material or electrode plate on which the master pattern is formed can be used any number of times once it is manufactured.

  Further, the same coating pattern can be formed even if the coating material is changed by using a master pattern formed by an electrode plate once manufactured. If the flow rate is adjusted, the thickness can be controlled while maintaining the same line width and dot diameter. By controlling this thickness, for example, an arbitrary resistance value can be set when drawing a resistance line.

  FIG. 27 shows a case where an entire circuit is formed as if a “jixor puzzle” is assembled by combining a plurality of mother pieces on which a master pattern is formed. Here, if the structure of FIG. 26 is used, the mother piece is an electrode plate 450, a base material A455 formed from a nonconductive material, and a base material B456 formed from a conductive material.

  Further, reference numeral 950 denotes a mother piece, 951 denotes an outer frame for accommodating a plurality of mother pieces 950, 952 denotes an electrode plate (corresponding to 450 in FIG. 26), and 953 denotes a master pattern formed through the electrode plate 952. . Furthermore, 954A and 954B are terminal portions of the master pattern. When a circuit composed of a resistor R, a capacitor C, and a coil I is formed by a sheet device, a mother piece having a specific value is prepared for each of R, C, and I, and any circuit can be obtained by combining them. Can be formed freely.

  At this time, the dimensions of the mother piece and the positions of the terminal portions may be standardized so that the positions coincide with the respective terminal portions.

  With this construction method, for example, even when a low-viscosity fluid of 100 mPa or less is used as the coating material, it is possible to draw an ultrathin line that was impossible with the conventional construction method. Alternatively, it is possible to draw a “thick thickness” coating line with a “thin width”. Therefore, an arbitrary coating pattern can be created using an ink jet system that is difficult to handle a high viscosity fluid.

  Further, as is common to the above-described embodiments, the timing of applying a voltage to the base material B formed of the boundary electrode and the conductive material is in the middle of coating if the coating material is charged to a predetermined charge. Alternatively, it may be after the application. Since the coating material is not easily neutralized, the material that protrudes from the boundary portion can be pulled back into the boundary due to the water repellent effect by the electric field.

  For example, after applying the low-viscosity fluid material on the organic film 200 in the configuration of FIG. 22, when the organic film 200 is detached from the other parts 203 a, 203 b, 201 in order to bake the coating material, it acts on the coating material. Since the “water-repellent effect” due to the electric field is eliminated, the coating line spreads in the width direction.

  As a countermeasure, the material may be thermally cured by irradiating a soft beam with leather against the coating pattern after coating or simultaneously with coating. Alternatively, it may be temporarily cured at a level that does not flow in the width direction, and then introduced into a firing furnace in earnest. Alternatively, for example, the material on the organic film may be cured by irradiating ultraviolet rays using a UV curable resin as a binder of the material.

  As the coating material used in the present construction method, any of fluid, powder, and powder fluid can be used. For example, it is possible to draw a high-quality coating pattern that does not scatter even when a toner jet, an electrostatic head, or the like, which has been a problem of scattering on the substrate when drawing a fine stripe or dot shape, is used.

  The thinner the organic film or the substrate to be coated is, the better the electric field effect can be obtained. If it is 1-2 mm or less, it is practically applicable, but if it is 0.5 mm or less, good results are obtained. If it is 0.1 mm or less, it is the best. In the case of a circuit pattern, the present invention can be effectively applied because it is easy to draw an electrode line for applying a voltage.

  With this construction method, as long as there is a master pattern, a flexible multilayer sheet device can be easily manufactured using an inexpensive dispenser such as an ink jet type or an air syringe type. Since the sheet device is thin and can be bent freely, the device can be installed in a limited space, and the electronic device can be thinned.

  FIG. 29 shows a case where the present invention is applied to screen printing.

  Apply a predetermined sign of charge to the coating material to be supplied to the substrate to be coated, apply a voltage of the same sign to the boundary electrode, and apply to the boundary using the apparent “water-repellent effect” by the electric field The idea of preventing the material from being loaded can be applied to a printing method such as screen printing. FIG. 28 shows an application example in the case where a phosphor layer is formed in a PDP cell.

  550 is a cell, 551 is a second substrate, 552 is an address electrode, 553 is rib A, 554 is rib B, 555 is a rib top electrode, 556 is a phosphor paste, 557 is a screen printing mask, 558 is a non-mask 557 Emulsion part 559 is a squeegee.

  The phosphor paste 556 is charged to a positive charge in advance, and a positive voltage with the same sign is applied to the rib top electrode 555. The address electrode 552 is grounded (voltage is zero).

  When the squeegee 559 is slid on the mask 557, the phosphor paste 556 passes through the non-emulsion portion 558 and is filled in the cell 550. In this filling process, the conventional screen printing method has a problem that the phosphor paste is placed on the tops of the ribs 553 and 554, leading to crosstalk between the barrier ribs. If the present invention is applied, the vicinity of the rib apex provided with the rib top electrode 555 has a “water-repellent effect” with respect to the phosphor paste 556, so the phosphor paste 556 is not attached to the rib top, Smoothly flows down inside the cell. Therefore, extremely reliable phosphor coating can be realized.

  The timing of applying a voltage to the rib top electrode 555 and the address electrode 552 may not be before the start of application, but may be during application or after the end of application.

  The case where the present invention is applied to the screen printing in which the phosphor in the PDP cell is filled has been described above. However, the present invention can also be applied to a method other than the PDP phosphor coating.

  For example, the present invention can also be applied to the above-described “method for forming a functional thin film on a thin organic film”. For example, in the sheet device method of FIG. 22, instead of supplying the application fluid from the discharge nozzle 205, an application pattern may be formed by screen printing.

  As described above, the case where the present invention is mainly applied to the phosphor coating of the PDP has been described as an example. However, the basic idea of the present invention is not limited to the type of material, the construction method, and the applicable product, and is applicable to various fields. Applicable.

Model diagram showing the first embodiment of the present invention The figure which expanded a part of model which shows the 1st example of the present invention. An enlarged top view of a part of the back plate Front sectional view enlarging a part of the back plate Side cross-sectional view enlarging a part of the back plate The figure which shows the analysis conditions of the electric field analysis of 1st Example by this invention (B) shows the analysis result of the voltage distribution (b) shows the analysis result of the electric field strength distribution (A) shows the analysis result of the air portion of the electric field vector (B) shows the analysis result of the dielectric portion of the electric field vector The figure which shows the analysis conditions of the electric field analysis of 2nd Example by this invention (A) is a diagram showing the analysis result of the air portion of the electric field vector (b) is a partially enlarged view The figure which shows the analysis result of the air part of the electric field vector by 3rd Example of this invention Figure showing the analysis result of electric field strength distribution The method of forming the rib electrode is shown, (A) is the rib intermediate part, (B) is the case where the rib electrode is formed at the lower end of the rib Model diagram showing a fourth embodiment of the present invention Figure showing the analysis result of air part of electric field vector Figure showing the analysis result of electric field strength distribution BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the whole structure of the dispenser to which this invention is applied, (A) is a top view, (B) is a figure which shows a front cross section. Diagram showing displacement curve of piston gap when supplying material with pulsating flow In the case of supplying the material by pulsating flow, (a) shows the flow rate state (b) shows the discharge nozzle (c) shows the independent cell Fig. 2 shows a state in which a phosphor is driven into an independent cell using an ink jet method, and Fig. 2A shows a state immediately after coating. Fig. 2B shows a state after drying. Model diagram when the present invention is applied to a toner jet system Model diagram when the present invention is applied to the sheet device method It is a figure which shows the state which formed the boundary electrode in the base material formed from a nonelectroconductive material, (a) is a top view (b) is a figure which shows a side surface A case where a coating line is formed on an organic film is shown, (A) is a top view, and (B) is a diagram showing an AA 'cross section of (A). Diagram showing the case where the boundary electrode is made into a thin plate The figure which combined organic film, base material A, and base material B The figure which shows the case where an electric field is formed between the discharge nozzle and the substrate A diagram that forms a whole circuit by combining mother pieces Model diagram when the present invention is applied to screen printing A diagram showing the behavior of a fluid flying from a discharge nozzle, where the discharge nozzle (a) is at the left end of the rib (b) is at the center of the rib (c) is at the right end of the rib, and (d) is a view showing the state of application completion The figure which shows the conventional air type dispenser Diagram showing conventional inkjet A diagram showing a conventional jet dispenser The figure which shows the structure of the plasma display panel (PDP) A diagram assuming a process in which a dispenser places a phosphor in an independent cell on the back of a PDP.

Explanation of symbols

10R, 10F Application pattern boundary 12 Electrode 3 Discharge port

Claims (28)

With the electrode formed in advance near the boundary of the coating pattern to be formed on the substrate, the coating material is charged to a charge having a predetermined sign, and a voltage having the same sign as the charge is applied to the electrode. The coating method is characterized in that the coating material is supplied toward the substrate to form the coating pattern. The voltage applied to the electrode is V _R , the electrode is arranged on the surface of the substrate on which the coating pattern is formed, or in the vicinity of the thickness direction of the substrate surface, and the voltage V _A different from the voltage V _R or zero is applied. The coating method according to claim 1. The coating method according to claim 1, wherein the coating material is supplied by ejecting the coating material from a discharge port disposed toward the substrate. The coating method according to claim 3, wherein a voltage V _N having the same sign as the voltage V _R is applied in the vicinity of the discharge port. 2. The coating method according to claim 1, wherein the coating material is a powder fluid containing powder in the fluid. 5. The coating method according to claim 4, wherein the voltage magnitude is set such that V _N > V _R > V _A. In a phosphor layer forming method for a plasma display panel, a phosphor layer is formed by sequentially supplying phosphor materials into a cell and forming a phosphor layer with respect to a substrate on which cells are formed with ribs as partition walls. The phosphor layer is formed by supplying the phosphor material to the cell in a state where a charge having a sign is charged and a voltage having the same sign as the charge is applied to an electrode disposed in the vicinity of the rib. A coating method characterized by the above. The phosphor material is sequentially applied to the inside of the cell by discharging the phosphor material from the discharge port toward the cell while moving the discharge port relative to the substrate. The coating method according to claim 7. 8. The voltage applied to the electrode is V _R, and a voltage V _A different from the voltage V _R or zero is applied to the address electrode disposed on the lower surface of the application target cell. Application method. The cell is an independent cell surrounded by the ribs, and the phosphor material is continuously discharged from the discharge port so that only the independent cell is filled with the phosphor material after the coating process is completed. The coating method according to claim 7. The electrode provided in a part of the rib was formed for the purpose of reducing the erroneous discharge due to the crosstalk to the cell B which is not the discharge target in the vicinity of the cell A with respect to the cell A which is the discharge target. The coating method according to claim 7. The coating method according to claim 7, wherein a voltage is applied to an electrode formed in advance on the top of the rib. The coating method according to claim 7, wherein a voltage V _N having the same sign as the voltage V _R applied to the rib is applied in the vicinity of the discharge port. The coating method according to claim 7, wherein a treatment having a water repellency effect is performed on the phosphor top portion in advance on the phosphor material. The closed cell one portion of the volume V _S, when the total flow rate of the closed-cell one minute corresponds flowing out from the discharge port was set to Q _S, according to claim 7, characterized in that the Q _S> V _S Application method. 8. The coating method according to claim 7, wherein the means for supplying the phosphor material is screen printing. 8. The coating method according to claim 7, wherein a voltage V _A2 having the same sign as the charge charged on the phosphor is applied to the address electrodes arranged on the left and right of the coating target cell with respect to the coating direction. . The coating method according to claim 7, wherein the voltage magnitude is set such that V _A2 > V _R. 4. The coating method according to claim 3, wherein the coating unit constituting the discharge port is a thread groove type dispenser. 4. The coating method according to claim 3, wherein the coating unit constituting the discharge port is an ink jet type. A boundary electrode along the shape of the coating pattern to be formed on the substrate is previously formed by a conductive member at a position on the opposite side of the substrate on which the coating pattern is formed, and a coating material is formed in a predetermined manner. The coating is characterized in that the coating pattern is formed by supplying the coating material toward the substrate in a state where the charge having a sign is charged and the voltage having the same sign as the charge is applied to the boundary electrode. Method. A master pattern that roughly matches the shape of the coating pattern to be formed on the substrate is formed in advance on the opposite side of the substrate from the side on which the coating pattern is formed, using a conductive member or a dielectric, and coating is performed. The material is charged to a charge having a predetermined sign, and the coating material is supplied toward the substrate in a state where a voltage different from the charge is applied to the master pattern or an electrode having a dielectric interposed therebetween. The coating method is characterized in that the coating pattern is formed. The coating method according to claim 21 or 22, wherein the thickness of the substrate is 0.1 mm or less. A conductive member is disposed on a side opposite to the substrate side with respect to the boundary electrode via a nonconductive member, and a voltage having a reverse sign or a value of zero is applied to the boundary electrode. Item 21 or 22 application method. The substrate and the conductive member are separated in a state where the coating material is temporarily cured after the coating pattern is formed, and then the coating material is baked on the substrate. Or the coating method of 22. The coating method according to claim 21 or 22, wherein a conductive pattern on which the boundary electrode is formed is used as an independent mother piece, and a plurality of mother pieces are combined to form a coating pattern. It consists of a substrate to be coated, a boundary portion of a pattern to be coated formed on the substrate surface or in the vicinity of the thickness direction of the substrate, and an electrode disposed in the vicinity of the boundary portion. The coating apparatus is characterized in that the pattern to be coated is formed by supplying the coating material toward the substrate in a state where a voltage having the same sign as the charge is applied to the electrode. A coating material comprising a substrate to be coated, a master pattern portion formed on the surface of the substrate or in the vicinity of the substrate in the thickness direction, and having a pattern that roughly matches the pattern to be coated, and an electrode disposed in the vicinity of the master pattern portion. Is charged to a charge having a predetermined sign, and the coating material is supplied toward the substrate while a voltage different from the charge or a zero voltage is applied to the electrode to form the pattern to be coated. A coating apparatus characterized by that.

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