TW478968B - Apparatus and method for coating fluorescent powder on a planar board - Google Patents

Abstract

The present invention provides an apparatus for coating powder on a planar board in an electrostatic manner, and a method using the apparatus. In the apparatus, a heating device is provided to heat a board to be coated and positioned on a powder spraying chamber to at least 100 DEG C. Furthermore, the board is charged by negative voltage of at least 20000 volts. Under a high temperature and a high voltage, another state of the non-conductive board results in a electrostatic conductive board. The powder particles charged by a high positive voltage inject to the surface of the board by at least 0.8 kg/cm<SP>2</SP> atmosphere pressure until the particles adhere on the surface of the board. Because of the simple processing step and no solvent being evaporated and released to the atmosphere, the novel method of the present invention is helpful in utilizing a low cost to perform an environment-harmless processing step. Because the simplified processing step, the present invention further provides a low-cost method to manufacture the flat display device.

Description

_Γ / V. Description of the invention (1) [Field of the invention] The present invention is generally about _ a kind of equipment and powder materials, especially frank, non-electrical conductors: about-the design plate will be added with a gas flame [Background of the invention ] In recent years, electronic devices such as flat-panel display personal computers have been developed. The advantage of the field = two is beyond the traditional liquid crystal ί = the phase of the liquid crystal display panel and the wide operating temperature The difference between the two display and the liquid crystal display is that, unlike the liquid crystal display, light generates a light source. The field caused: ^ light and filters, the results can be seen by the user. Further :: Five arrays of thin film transistors are required, and for the second, the cost and main cause of the field emission display, the electronic system is a fluorescent coating layer i, such as a transparent overlay to produce an image. This cathode cold light process is an efficient method. In contrast to the conventional cathode ray method and method, the method and the method are used for coating and a method on a flat plate, and in a substantially flat coating method, the fluorescent heat is applied and charged with a negative charge. The device is also widely used in some defects such as the FED device, that is, the display, and has a display device. For example, compared with the transmission, the field emission display device has a higher maximum brightness and a lower range. A basically biggest difference is that the emission display itself utilizes the display, which does not require complicated, energy-consuming emission display light. The field emission display does not require the source for the active matrix liquid crystal display to be eliminated. A cathode emerges and collides with a phosphorescent layer on the back of a plate, as a known light-generating tube (CRT) device, in contrast, is present.

f page 5 5. Description of the invention (2) In the emission display source, that is, to transmit the existing potential light layer. The quality and uniformity covered by this stone ballast are important steps in transparent glass. Traditionally, in the powder layer, the two processed solvents are used for the glass plate. After the plate has to be baked in the kiln and immersed and coated, and the evaporation step is released, this device will cause the coating to be fluorescent. Powder material The additional fluorescent powder material of the present invention is electrostatically coated and the plate is charged with another pixel or radiation unit of the present invention having its own electron

St: Microtip array. Between the cathode and the gate, the cathode sucks out the optical layer, and accelerates it to the plate. The raw image therefore relies heavily on the phosphorescent coating. The process of coating the phosphorescent layer throughout the entire field emission display manufacturing process is a heavy flat transparent plate (or on the flat bulb root). Fluorescence can be done by printing, black screen printing or dip coating. During the process, the screen-printed or dip-coated emulsion contains a large amount of f-shaped gel or emulsion. After the jelly was printed on a slope or S glass plate was impregnated to coat the emulsion, the soil was baked to evaporate all the solvents. Therefore, the screen printing process not only complicates the manufacturing process, but also causes pollution to the environment after processing. This complicated processing further reduces the manufacturing productivity. One object is to provide a device for coating a plate &apos; which does not have the disadvantages or disadvantages of the conventional device. An object is to provide a device for coating on a flat plate 'which operates on the principle of electrostatic coating. The purpose of this step is to provide a device for a plate of glorious powder material that uses a gas flame to heat the plate to a negative charge. A further object is to provide a device for

478968 V. Description of the invention (3) Coating on a flat plate Rotating a flat plate, a fluorescent powder material, the flat plate is fixed and the light is coated with fluorescent light. . And this plate is covered with fluorescent light and the plate is heated to be filled with positive fluorescent light and heated under air pressure [invented according to the Tan plate in one bright and another powder material at the same time to Ming and another powder material is electric Another τ% temperature, the electric powder powder material will be rotated and guided to this overview] The present invention applies a better solid powder, wherein the top and the top are heated by a heating material, which can be applied to the powder during the electrostatic coating process. Spray room. The purpose is to provide a device for coating a plate and heating the plate to a temperature of at least 100 and a negative voltage of at least 2 ◦, 0 ◦ 0 volts. A device is provided for coating a powder on a plate by electrostatically coating the powder on a plate. A method is provided by charging a glass plate with a negative charge to a high voltage, and then placing the surface of the plate on a plate. Plate coating provides a method by which a plate of powder is simultaneously charged with positively charged powder particles above the plate and coated with a fluorescent powder material. Material, which can charge the board, is aimed at material, which can be non-conductive. One purpose is to lead the fine particles to the material at the same time. One purpose is to charge the surface of the plate with a negative charge, and 'provide a device and method' for a substantially flat fluorescent powder. In an embodiment, a device is provided on a flat plate in an electrostatic manner. The device includes a chamber having a top opening, a bottom housing a cavity, a plate positioned at the top of the chamber, and generally open. The plate has a surface for coating. The bottom surface of the cover, the opening facing the cavity, a heating device for a top of the board, the top surface is opposite to the bottom surface, and the upper coating opening and the upper seal are exposed on the surface

Description of the Invention (4) _ The reading board is electrically grounded, a powder opening, Β -Γ re ^ ^ ^, the service mouth is suitable for engaging the bottom port of the room, and can be used to receive positive voltage. "UA instead of the heating device to form a closed dual-purpose U to rotate the chamber and position at the ▼ press-fitting Putian 丨, / s ▲ taxi, department, see" The device of the board on X, and 1 clothing for driving The powder is charged to the L ice wi rail, Wu Guan 嗝 'through the spray electrostatic charge and the powder is charged at a positive% η element, so that the surface of the powder department is attached. — The electrostatic coating chamber on the flat plate has a cylindrical shape, and the device further includes a diameter. The equipment may further include—the temperature at the top of the t is greater than the bottom to hold at least 100 ° C. The "banpo" is separated from the chamber, which can resist powder coating on it. The plate may be a glass plate, which is used to display a fluorescent plate. The device can be further inverted for use in making a plurality of flat gas nozzles for sounding the temperature of the plate ^ 加热 a heating device comprising between 25 (rc, and preferably about 10 W heat to Approx. 100 ° to approx.-For electrostatically coating the powder on the plate ^ between approximately 200 ° C. Heating device 'which includes multiple gas sprays. The device can further include-the plate provides conductivity This makes the: for heating the plate and further including a variety of equipment for the ground. The powder spray nozzle equipment may have individual channels, toilet pendant = through the end, the various degrees. The The line received by the powder spray nozzle forms an angle of 0 ° to 45 ° to approximately 50,000 volts. The deflection pressure is located at approximately 20,000 volts: for electrostatic coating on a board The rotor element is meshed with the chamber, and it may further include a rotational displacement between 20 rms. The chamber is approximately 1 RPM to approximately further including a gas supply

5. Description of the invention (5) A storage tank for conveying flammable gas to the heating device. The equipment is provided with a glue-recovery unit for recovering powder on the bottom surface of the chamber cavity which is not adhered to the powder, and the powder recovery element is arranged in parallel with the powder spray nozzle. The high pressure device causes powder to flow through the powder spray nozzle at a pressure between about 0.8 kg / cm2 and about 8 kg / cm2. The apparatus may further include a powder supply device for transferring powder to the spray nozzle under the pressure of compressed air, and the powder supply device may further include a stirring device to ensure that the powder can flow freely. ^ ^ = Further directed to a method for electrostatically coating a plate on a plate. The eight steps include first providing a powder spray chamber having a top surface to the plate— + as a coated plate, and The first surface is exposed to the second entry ΓΓ for coating, and the plate is heated with a gas flame. The second and third surfaces of the opposite t = 10 (rc, the same negative voltage to the second ping VZU, UUIM is located in the bean The top 3 table is charged, the chamber is rotated by a rotating device, and the% with positive charge is passed through the bottom opening of the chamber by air pressure in the plate with a negatively charged M ^ σσ cavity, so that the powder It is adhered and adhered to a surface of a genius. Steps include the steps of the method of coating powder by fixing 彳 t Sf, and a plurality of the second surface of the plate side by side with gas fire ^ 2 = can be further added. Gas nozzle, between 2 50 t: between the side, go ..., until the temperature reaches about 100 ° C to about the device rotation, and the step of installing may further include rotating the chamber with a friction force The rotation speed of about 1RPM to about 20RPM includes the second f of the board. The final spray chamber. The steps of this method can be further increased from about 20,000 volts to about 50,000 () volts.

P99-049.ptd Page 8 478968 V. Description of the invention (6) Special negative voltage charging. The step of the method may further include injecting the positively charged powder into the cavity by an air pressure of at least 0.8 kg / cm2. The steps of the method for electrostatically coating powder on a board may further include injecting the positively charged powder into the cavity, and the powder is charged at a voltage of at least 20,000 volts. The method may further include ejecting the powder through a powder spray nozzle provided with a plurality of openings. The method step may further include supplying the powder from a powder supply hopper equipped with a stirrer. The steps of the method may further include recovering the used powder from the cavity of the chamber for recycling. [Detailed description of the preferred embodiment] The present invention discloses a device and method for electrostatically coating fluorescent powder on a substantially flat plate, the plate being an electric non-conductor. In the device, a novel heating device is used to heat the board, and at the same time, the board is charged with negative electricity, so that the powder charged with positive electricity is adhered and adhered to the board. The present invention is intended to remove the disadvantages of this conventional coating method, which include time-consuming processing steps and environmental pollution issues. This method uses the principle of electrostatic coating, in which a high-voltage current and a gas flame are used to change the electrical characteristics of the non-conductive substrate so that it can conduct electricity during the electrostatic coating process. The novel method of the present invention effectively reduces or eliminates the organic solvent used in the gel or emulsion, and further increases the yield of the manufacturing process. The novel method of the present invention is therefore particularly suitable for use in high volume manufacturing processes and can be performed at low cost. The novel method of the present invention is performed by first heating a glass substrate, and then

P99-049.ptd Page 9 478968 V. Description of the invention (7) The substrate is charged at a high voltage, so that a negative static load can be generated in the glass substrate. A positively charged fluorescent powder, such as a phosphorescent powder, is then passed through a powder spray nozzle with compressed air, and is fired at the glass plate, so as to restore the alpha-hydrogen J from the substrate. The uniformity and thickness of the coating layer obtained are determined by &quot; rounding the flow of the high-pressure air.

In a flat panel display device, a small amount of inert gas will be filled into the sealed cavity between the two flat plates. After a high voltage is input to the two ends of the cavity, the inert gas will emit UV radiation. The UV radiation induces the fluorescent powder coating surfaces of the two flat plates, so that the U ν frequency is converted into the flatness of visible light by the fluorescent powder beam.

Referring to FIG. 1, there is shown a device according to the present invention for coating a fluorescent powder on a plate. The device 10 is mainly composed of a powder spraying chamber 20, a heating device 30, a powder spraying nozzle 40, and a powder recovery unit 50. The powder spraying chamber 20 has a top opening 22, a bottom punch opening 24, and a cavity 26 therein. A generally flat plate 28 has a surface 32 for covering, which is located in the top opening 22, and the surface 32 faces the cavity 26. A powder spray nozzle 40 is engaged with the bottom opening 24 and substantially seals the bottom opening and the passage 36 to collect the used powder and transfer it to the powder recovery unit 50. The electromagnetic shut-off valves 38, 42 and 44 are used to further control the flow of the recovered powder and the flow of the powder fed to the cavity 26, respectively. The plate 28 has a surface 32 for coating. When positioned on the top slit 22, the opening is substantially sealed to form an airtight enclosure for the cavity 26. On the uncoated side 34 of the plate 28, a brass plate 46 and more

49. ptd

V. Description of the invention (8) One body nozzle 48 is configured to generate a uniform power source 5 2 to be supplied between the plurality of novel squares C in the present invention and the electrostatic coating voltage is up to about 40 heating device 3 0 ′ It is used to supply heat to generate multiple gas flames and make it a distributed heat source. About 20,000 volts to about 50,000 volts on a brass plate 46. A flammable gas is contained in the gas nozzle 48, and the flammable gas used to heat the flat plate novel equipment is propane. In general, the plate 28 should be heated to a temperature of about 100 ° C, preferably at a temperature of about 100 ° C to about 200 ° C. The voltage of the power supply 52 should be between about 50,000 volts, and preferably between about 50,000 volts. The number of gas nozzles is 48. The plurality of gas surfaces of the plate 34 can be supplied to 28 at the same time by a negative voltage storage tank 5 4. A structure suitable for implementing the present invention between 100 QC and about 2 50 to complete the structure located at about 2 0,00 and about 3 0,0 0 volts. It is cylindrical with a larger diameter at the top and a smaller diameter at the bottom. A suitable size for the chamber is about 6 inches tall and a diameter of 3 inches in the center of the chamber. The two powder supply hoppers 60 are used to supply the powder coating material to the input nozzles and springs 6 2 and enter the powder spray nozzles 40. The powder supply hopper 60 is equipped with a mixer 64 to ensure that the powder can flow without interruption through the inlet duct 62. The feeding of the powder can be performed by a high-pressure compressed air source 70. The air source 70 can supply an air pressure between about 0.8 kg / cm2 and about 8 kg / cm2. The input catheter 62 used may have a diameter of about 10 mm. The flow of the compressed air from the air source 70 is controlled by reading the pressure gauge 56 with an electromagnetic shutoff valve 44. The pressure indicated on the pressure gauge 56 is R1 'and the pressure indicated on the pressure gauge 58 is R2.

P99-049.ptd Page 11 / ^ 68 V. Description of the invention (9) As shown in Fig. 1, the R1 pressure is controlled so that the feed hopper 60 is fed to the input duct 62, and at the same time, the knowledge is controlled by S "terminal ( 2. The feeding of the Li powder by the input duct 62 is for force application, and the second one is equipped with a plurality of openings (not shown) so that the fine particles of the powder can be injected into the cavity 26. The powder spray The continuous porosity that is present in the nozzle 40 usually forms about 0 and about 2 angles with the vertical axis so that the powder particles 66 can fan the pattern toward the ten-plate, four-way, and two-way electrostatic coating process. First, the plate 28 will be heated i :: degree f less than 100 c, and at the same time charged with a negative voltage of at least 20, volts], so that an electrostatic charge will be generated on the plate 28. Figure. A], the Thousand plate 28 is further rotated by a rotating speed of 10RPM, one of the mechanisms shown in Fig. 1A. Large J1RPM to eight are shown in Fig. 1A. The chamber 20 is first fixed on the rotor element side. The element 80 is covered by a silicone rubber-coated collar 82, the sliding sleeve and It is composed of a pulley 86, wherein the collar engages the bottom opening 24 of the chamber 20 with a friction force, the rubber rubberized collar 82 is fixed in the sleeve 84, and the pulley 86 is an electric motor 90 Driven by a support belt 88. The powder spray chamber 20 frictionally engages the silicone rubber-coated collar 82, and during the electrostatic coating process, rotates with the collar at an appropriate rotation speed of about 丨 rPm to about 10 RPM. 82 Rotate together. Please understand that the powder mist nozzle 40 is fixed on a fixed shaft 76, so it will not rotate with the chamber 20 during the electrostatic coating process. As shown in the figure, the used Powder, that is, not adhered to the surface 32 of the plate 28

P99-〇49.ptd Page 12 ^ / 〇yO〇 Five, the description of the invention (10)-the powder will be collected in the recovery channel 3 6 (shown) to a powder recovery unit 50 kg, H side of The vacuum force is controlled by the unopened valve 38. In each spray coating, the 36 is electromagnetically closed and "will be closed, and the electromagnetic shut-off valve 3 J 'electromagnetic shut-off valve 42 26 is used to recover the used 1 powder, so that each electrostatic coating process from the chamber cavity takes about 丨 seconds to about 1 second to about 2 seconds. The plate is private, and preferably at a large thickness of about 1 〇 # m To about 5 (), to a more appropriate coating of about 40 ㈣. For the powder supply; 好 good at about 20 ㈣ to large, and then add at least the weight ratio under the action of air pressure, since the day strong Grab the 剤 to ensure the powder is in the powder spray nozzle 40. The = tube 62 enters about 1 to about 20 ㈣, and preferably between W, and the appropriate particle size of the car's parent. A fine when the terrace is recognized For the reason, take f as shown in about 3 # m to about 7 # m; cover the type of flat panel light. In Figure 1, about 2 inches to about 5 inches. The i-book is issued on the length of the adjacent measuring side; the new 32: the flat type of the equipment is suitable for showing in Figures 1 and 1A. Spacer 98. This figure is only a flat plate 96, which is equipped with a brush for processing. On the same day 1, * f92, 96 cannot be used in traditional equipment. The solvent contained in the screen printing material = is not only time consuming, but also because In the new coating applied in the present invention;!: It is also harmful to the mounting environment. The ratio of the air pressure into the chamber cavity through the transmission layer of the coating layer is 100%. (R 2) _ P99-049.ptd Page 13 478968 V. Description of the invention (π) Dependence is shown in Figure 4. When the air pressure Rl405kg / cm2, in the powder spray nozzle, When the opening is maintained at an angle of 60 °, the transmission fraction will increase as the R2 pressure increases. This shows the fact that when the shot percentage increases, a thinner coating is formed on the surface of the plate. At higher R2 pressure, less coating material will be applied to the surface of the board 'because the powder will be blown into a more diffuse pattern Figures 5 and 6 show that when the R1 pressure (for feeding the hopper belt from the powder, the last pressure) is increased, the opposite effect to that of Figure 4 is produced. When the R2 pressure is fixed = 0.8 kg / cm2, and the When the opening is maintained at an angle of 60 °, the data of 仟 is shown in Fig. 5. When the R2 pressure is fixed at 〇8 kg / cm2, and on the same day! When the opening is maintained at an angle of 70. &amp; The pressure of R1 will bring more powder material into the cavity, and a heavier coating will be formed on the flat surface, so the transmittance will decrease accordingly. Main tool: different opening angles, That is 60. And 70. The two types are different in terms of their dependencies, as compared to the end nozzle. The novel device of the present invention and the method of using the device are therefore described in detail in the accompanying drawings of FIG. Technique = invention is disclosed in detail by way of illustration, but it should be understood that the spirit used is for illustration and not for limiting the scope of the invention. Although although the present invention has been disclosed in the foregoing preferred embodiments, it is not the spirit and r 円 βη ". Artists can make various changes and modifications without departing from the scope of the present invention. Therefore, the present invention The dry envelope is subject to the attached application, whichever is defined by the patent scope.

Page 14 478968 Brief description of the drawings [Outline description of the drawings] Fig. 1 is a schematic diagram showing the device of the present invention for electrostatically coating powder on a board. FIG. 1A is an enlarged cross-sectional view showing the powder spraying chamber in FIG. 1 and a rotating mechanism of the chamber. Fig. 2 is a perspective view of a flat plate having a side frame. Figure 3 is a perspective view of a plate having spacers fixed to the surface of the plate. Fig. 4 is a graph showing the dependence of the air pressure on the transmission percentage used to inject powder into the chamber. Figure: 5 is a graph showing the dependence of the air pressure on the transmission percentage when the powder spray nozzle is formed at 60 ° to feed the hopper from the powder to the powder supply line to the chamber. . FIG. 6 is a graph showing the dependence of the air pressure on the transmission percentage when the opening is formed in the powder spray nozzle at 70 ° to feed the hopper from the powder to the powder supply line to the chamber. . [Explanation of drawing number] 10 Equipment 20 Powder spraying chamber 22 Top opening σ 24 Bottom opening 26 Cavity 28 Plate 30 Heating device 32 Surface 36 Channel 38 Electromagnetic shut-off 40 Powder spray mist nozzle 4 2 Electromagnetic shut-off

P99-049.ptd Page 15 478968

Brief description of drawings 44 Solenoid shut-off valve 46 Brass plate 48 Gas nozzle 50 Powder recovery unit 52 Power supply 54 Gas storage tank 56 Pressure gauge 58 Pressure gauge 60 Powder supply hopper 62 Input line 64 Agitator 66 Fine particles 70 Air source 76 Fixed shaft 80 Rotor element 82 Collar 84 Sleeve 86 Pulley 88 Belt 90 Electric motor 92 Plate 94 Frame element 96 Plate 98 Spacer P99-049.ptd Page 16

Claims (1)

478968 VI. Application for patent scope 1. A device for electrostatically coating powder on a flat plate, comprising: a chamber having a top opening, a bottom opening, and a cavity accommodated therein; a plate positioned at the top of the chamber, The top opening is substantially sealed, the plate has a bottom surface for coating, exposed to the top opening facing the cavity; a heating device for heating the plate on the top surface opposite the bottom surface, and The plate is electrically grounded; a device for rotating the chamber and the plate positioned on the chamber; and a high voltage device for flowing powder through the spray nozzle and for charging the powder with a positive electrostatic charge, This allows the powder to adhere to the bottom surface of the board for negative charging. 2. The device for electrostatically coating powder on a flat plate according to item 1 of the scope of patent application, further comprising a chamber having a cylindrical outer shape, and a diameter at the top thereof is larger than a diameter at the bottom thereof. 3. The device for electrostatically coating powder on a flat plate according to item 1 of the scope of patent application, further comprising a chamber made of glass, which can withstand a temperature of at least 100 ° C. 4. The device for electrostatically coating powder on a flat plate according to item 1 of the scope of patent application, wherein the plate is a glass plate for coating the fluorescent powder thereon. P99-049.ptd Page 17 478968 6. Application scope 5. The device for electrostatically coating powder on a flat plate according to item 1 of the scope of patent application, wherein the plate is a glass plate for manufacturing flat display devices . 6. The device for electrostatically coating powder on a flat plate according to item 1 of the scope of the patent application, further comprising a heating device of one of a plurality of gas nozzles for forming a gas flame layer after ignition. 7. The device for electrostatically coating powder on a flat plate according to item 1 of the scope of patent application, further comprising one of a plurality of gas nozzle heating devices for heating the plate to a temperature of 100 ° C to 250 ° C. 8. The device for electrostatically coating powder on a plate according to item 1 of the scope of patent application, further comprising one of a plurality of gas nozzles for heating the plate to a temperature of 100 ° C to 200 ° C. ° C. 9. The device for electrostatically coating powder on a flat plate according to item 1 of the scope of patent application, further comprising one of a plurality of gas nozzles heating means for heating the plate and providing electrical conductivity to the plate, so that The board is grounded. 10. The device for electrostatically coating powder on a flat plate according to item 1 of the scope of the patent application, wherein the powder spray nozzle includes a plurality of openings for allowing powder particles to pass therethrough. P99-049.ptd Page 18 478968 6. Application for patent scope 1 1. The device for electrostatically coating powder on a flat plate according to item 1 of the scope of patent application, wherein the powder spray nozzle includes a plurality of openings, and Each opening has a channel that forms an angle of about 0 ° to about 45 ° with a vertical axis. 1 2. The device for electrostatically coating powder on a flat plate according to item 1 of the scope of the patent application, further comprising the positive voltage accepted by the powder spray nozzle between 20,000 and 50,000 volts. Between 0 volts. 1 3. The device for electrostatically coating powder on a flat plate according to item 1 of the scope of patent application, further comprising a rotor element engaged with the chamber to provide a rotational displacement of the chamber between 1RPM and 20RPM. 1 4. The device for electrostatically coating powder on a flat plate according to item 1 of the scope of patent application, further comprising a gas supply storage tank for transferring a flammable gas to the heating device. 1 5. The device for electrostatically coating powder on a plate according to item 1 of the scope of patent application, further comprising a powder recovery device for recovering powder from the chamber cavity that is not adhered to the bottom surface of the plate. The powder recovery element is arranged in parallel with the powder spray nozzle. 16. The device for electrostatically coating powder on a flat plate according to item 1 of the scope of patent application, wherein the high voltage device is between 0.8 kg / cm2 and 8 kg / cm2. P99-049.ptd Page 19 478968 I Sixth, the scope of patent application Pressure to make the powder flow through the powder spray nozzle. 1 7. The device for electrostatically coating powder on a flat plate according to item 1 of the scope of patent application, further comprising a powder supply device for conveying powder to the spray nozzle under the action of compressed air, the powder supply device further Assemble a stirring device to ensure that the powder flows freely. 1 L A method for electrostatically coating powder on a flat plate, comprising the steps of: providing a powder spray chamber having a top opening for engaging a plate to be coated thereon, and The plate is used to coat a first surface exposed to a cavity of the chamber; the plate is heated to at least 100 ° C with a gas flame on a second surface opposite to the first surface, and at the same time The second surface is charged with a negative voltage of at least 20,000 volts; the chamber is rotated by a rotating device and the plate at the top; and the positively charged powder is passed through the bottom opening of the chamber by air pressure It is injected into the cavity, so that the powder adheres to and adheres to the first negatively charged surface of the board. 19. The method for electrostatically coating powder on a flat plate according to item 18 of the scope of patent application, the steps further comprising by positioning a plurality of gas nozzles juxtaposed with the second surface of the plate, The gas flame heats up to a temperature between 100 ° C and 250 ° C. II P99-049.ptd Page 20 478968 Patent application scope 20 · The method of electrostatically coating powder on a flat plate according to item 18 of the patent application scope, the steps further comprising rotating the chamber with a rotating device, the The square-shaped garment was placed at a rotation speed of 1 RPM to 20 RPM, and the powder spray chamber was shouted with friction. 2 1 · The method for electrostatically coating powder f on a flat plate according to item 8 of the scope of the patent application, the steps further comprising the step of applying the second surface of the plate from 20,000 volts to 50,000. Charged to a negative voltage of 0 volts. According to item 18 of the scope of patent application, applying electrostatic pressure to a plate on a flat plate, and the step further includes ejecting the positively charged powder with an air force of at least 0.8 kg / cm2. • According to Shen Yan's patent—the method, Soya ,, ;; a plate is coated with electrostatic powder on the plate, and the powder ;: further includes injecting the positively charged powder into the cavity X Zhimo has at least 2 0,0 0 0 volts. • The method of applying to item 1 of the scope of patent application No. 18, the steps of which are shot into a cow bowl and plate with electrostatic coating powder, and the nozzles, y, and dust are sprayed through a powder spray. Multiple openings. I knife not shellfish 1 at the end of the application according to the scope of patent application No. 24 on a tablet _ powder with a stirrer 478968 P99-049.ptd Page 22