JP2006164994A - Device and method for forming phosphor layer of plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manufacture a PDP having high display quality by preventing uneven display caused by an applied amount of phosphor paste. <P>SOLUTION: This device forms a phosphor layer by applying phosphor paste to a groove formed between a plurality of ribs formed on the surface of a substrate. The device for forming the phosphor layer of a plasma display panel is equipped with a placing table to place the substrate, a nozzle head having a plurality of nozzles arranged in a line to discharge the phosphor paste, a supply part to supply the phosphor paste to the nozzle head, a rectilinear movement part to relatively move the nozzle head and the placing table rectilinearly, and a rotation part to relatively rotate the nozzle head and the placing table. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an apparatus and a method for forming a phosphor layer between ribs of a substrate which is used in a manufacturing process of a plasma display panel (hereinafter referred to as PDP) and has a plurality of ribs (partition walls) on the surface.

  2. Description of the Related Art Conventional PDP phosphor layer forming apparatuses and methods are known in which phosphor paste is applied to grooves between ribs using a nozzle head having a plurality of nozzles (so-called multi-nozzles). However, as the size of the PDP increases, that is, the size of the substrate increases, it becomes difficult to apply the entire surface of the substrate at once, and the substrate application region is divided into a plurality of small regions corresponding to the applicable width of the nozzle head. Each of the small areas has been sequentially applied with a nozzle head.

By the way, if the amount of the phosphor paste applied to the groove between the ribs or the concentration of the phosphor contained in the phosphor paste varies, it adversely affects the display characteristics of the PDP. In order to obtain it, it is necessary to manage the coating amount and the concentration of the fluorescent substance in the paste with high accuracy.
Therefore, it is known that the viscosity of the phosphor paste is set to be relatively low and is applied by utilizing the surface tension of the phosphor paste, or the relationship between the nozzle length and the aperture is variously controlled ( For example, see Patent Documents 1 and 2).
Japanese Patent Laid-Open No. 11-40065 Japanese Patent Laid-Open No. 11-73882

  However, in order to manufacture a large PDP with high display quality, the problem of variation in the discharge amount between nozzles appears as a difference in the application amount at the boundary between the divided application regions, resulting in display unevenness. There is a need to.

  The present invention has been made in consideration of such circumstances. By devising the coating procedure so that the difference in coating amount at the boundary of the coating region is not noticeable, a large PDP with high display quality can be obtained. A phosphor layer forming apparatus and a method for forming the same are provided.

  The present invention is an apparatus for forming a phosphor layer by applying a phosphor paste to a groove formed between a plurality of ribs provided on a substrate surface, and a mounting table on which a substrate is mounted, Nozzle head in which a plurality of nozzles for discharging body paste are arranged in a line, a supply unit for supplying phosphor paste to the nozzle head, a linear moving unit for relatively linearly moving the nozzle head and the mounting table, and a nozzle head The present invention provides a phosphor layer forming apparatus for a plasma display panel that includes a rotating unit that relatively rotates the mounting table.

  The present invention is also a method for forming a phosphor layer of a plasma display panel using the phosphor layer forming apparatus, wherein a plurality of small regions are formed by making the phosphor paste application region of the substrate correspond to the number of nozzles of the nozzle head. The first step of applying the phosphor paste by relatively moving the nozzle head and the mounting table in the rib direction and the second step of reversing the nozzle head and the mounting table relatively 180 degrees are combined. The present invention provides a method for forming a phosphor layer of a plasma display panel, characterized in that a phosphor paste is applied to grooves in each small region.

  According to the present invention, since the nozzle head and the substrate can be reversed 180 degrees so that the coating operation can be performed, variation in the coating amount at the boundary of the coating region on the substrate is suppressed, and display unevenness in the PDP is prevented. By doing so, it becomes possible to manufacture a large PDP with high display quality.

  The plasma display panel (PDP) according to the present invention is such that a discharge is locally generated between two opposing substrates to excite and emit a phosphor layer partitioned on the substrate. This is composed of a pair of substrate assemblies 50 and 50a as shown in FIG. 1 (for one pixel), for example.

  In the substrate assembly 50a, a pair of sustain electrodes X and Y for generating surface discharge along the substrate surface are arranged on the inner surface of the front glass substrate 11 for each line. The sustain electrodes X and Y are each composed of a wide straight strip-like transparent electrode 41 made of an ITO thin film and a narrow straight strip-like bus electrode 42 made of a metal thin film.

  The bus electrode 42 is an auxiliary electrode for ensuring proper conductivity. A dielectric layer 17 is provided so as to cover the sustain electrodes X and Y, and a protective film 18 is deposited on the surface of the dielectric layer 17. Both the dielectric layer 17 and the protective film 18 are translucent.

  Next, in the substrate assembly 50, the address electrodes A are arranged on the inner surface of the glass substrate 21 on the back side so as to be orthogonal to the sustain electrodes X and Y. Between each address electrode A, one linear partition, that is, a rib r is provided.

  In the substrate assembly 50, these ribs r divide the discharge space 30 into sub-pixels (unit light emitting regions) EU in the line direction and define the gap size of the discharge space 30.

  A phosphor layer 28 of three colors R, G, and B for color display is provided so as to cover the rear side wall surface including the upper portion of the address electrode A and the side surface of the rib r.

  The rib r is made of low-melting glass and is opaque to ultraviolet rays. As a method for forming the ribs r, for example, a process of providing an etching mask by photolithography on a solid film-like low melting point glass layer and patterning by sandblasting is used.

  The sustain electrode pair 12 corresponds to one line of the matrix display, and one address electrode A corresponds to one column. Three columns correspond to one pixel (pixel) EG. That is, one pixel EG includes three subpixels EU of R, G, and B arranged in the line direction.

  By the opposing discharge between the address electrode A and the sustain electrode Y, the wall charge accumulation state in the dielectric layer 17 is controlled. When a sustain pulse is alternately applied to the sustain electrodes X and Y, a surface discharge (main discharge) is generated in the subpixel EU in which a predetermined amount of wall charges exist.

  The phosphor layer 28 is excited locally by ultraviolet rays generated by surface discharge and emits visible light of a predetermined color. Of this visible light, the light transmitted through the glass substrate 11 becomes display light. Since the arrangement pattern of the ribs r is a so-called stripe pattern, the portion corresponding to each column in the discharge space 30 is continuous in the column direction across all the lines. The light emission colors of the subpixels EU in each column are the same.

  In manufacturing such a PDP, the phosphor layer 28 is formed after providing the address electrodes A and the ribs r on the substrate 21 as shown in FIG.

  Moreover, the phosphor paste (paste-like phosphor) for forming the phosphor layer 28 is, for example, a mixture of 10 to 50 wt% of powder phosphor material for each color, 5 wt% of ethyl cellulose, and 45 to 85 wt% of BCA.

For example, (Y, Gd) BO ₃ : Eu is used as the red fluorescent material, and for example, Zn ₂ SiO ₄ : Mn or BaAl ₁₂ O ₁₉ : Mn is used as the green fluorescent material. For example, 3 (Ba, Mg) O.8Al ₂ O ₃ ; Eu can be used as the substance.

  In the nozzle head that discharges the phosphor paste, the nozzle inner diameter is set to be smaller than the rib interval, but the nozzle tip is not inserted between the ribs, so the outer diameter of the tip is rib It may be larger than the interval. For example, when the rib interval is 250 to 300 μm, the nozzle preferably has an inner diameter of 200 to 250 μm and an outer diameter of about 400 to 450 μm. In addition, a nozzle head in which a plurality of (for example, 50 to 150) nozzles are arranged in a line at a pitch that is an integral multiple of the rib pitch can be used.

  The precipitation preventing device in the phosphor layer forming apparatus according to the present invention preferably has its operation interlocked with the pause operation of the nozzle head. This is because the paste in the nozzle head storage chamber always flows during the nozzle head coating operation, and the fluorescent material does not precipitate.

The precipitation preventing device may be composed of an ultrasonic oscillator.
In this case, the particles of the fluorescent material are moved in the paste by the vibration of the ultrasonic oscillator, so that precipitation is prevented. The specifications and the number of ultrasonic oscillators are determined by the capacity of the nozzle head storage chamber.
The precipitation preventing device may be composed of a Peltier element.
In this case, if the phosphor paste is cooled by the Peltier element, the viscosity is increased to prevent precipitation of the phosphor, and if heated, the viscosity is lowered and the fluidity is increased. Therefore, it is possible to control the flowability and discharge characteristics of the phosphor paste with respect to the nozzle.

  The Peltier element here is an electronic cooling element in which an N-type semiconductor and a P-type semiconductor are joined with a metal piece. In the N-type, the direction of current is opposite to the direction of current by flowing a direct current from the N-type semiconductor to the P-type semiconductor. Furthermore, in the P type, the movement of heat occurs in the forward direction, the metal piece joining the two is cooled, and by passing a direct current from the P type semiconductor to the N type semiconductor in the reverse direction, It is comprised so that it may be heated, A general commercial thing, for example, the product made by Fujitaka Co., Ltd. (6.0A, 17.5V, temperature difference 72 degreeC) can be used.

  Note that the required capacity of the Peltier element is determined by the heat capacity of the nozzle head, the capacity cooling temperature of the storage chamber, the environmental temperature, etc. If the capacity of the Peltier element alone is small, it is necessary to use multiple Peltier elements. Can accommodate capacity.

  Therefore, it is preferable to provide a circuit capable of selectively supplying a direct current in the forward direction and the reverse direction to the Peltier elements connected in series or in parallel.

  In the phosphor layer forming apparatus according to the present invention, when a predetermined number of nozzles at both ends of the nozzle row of the nozzle head are used as dummy nozzles, and a recovery device for collecting the phosphor paste discharged from the dummy nozzles is provided, Since the nozzle does not contribute to the application work of the phosphor paste and improves the fluidity of the phosphor paste with respect to the remaining nozzles, variation in the application amount between the grooves is suppressed.

The collection device may be a tray fixed to the head, and the tray may receive the phosphor paste discharged from the dummy nozzle.
The dummy nozzle is preferably shorter in length than the remaining nozzles. Thereby, it becomes easy to provide a collecting device, for example, a tray between the tip of the dummy nozzle and the substrate.

It is preferable that the collecting device includes a tray that receives the phosphor paste discharged from the dummy nozzle and a transport device that transports the phosphor paste on the tray to the supply unit. Thereby, the phosphor paste discharged from the dummy nozzle can be reused.
The dummy nozzle may be a side nozzle provided on the side surface of the nozzle head so as to protrude in a direction orthogonal to the remaining nozzles.

  In the phosphor layer forming apparatus of the present invention, a mounting table for placing a substrate, a nozzle head having a plurality of nozzles for discharging the phosphor paste, a supply unit for supplying the phosphor paste to the nozzle head, a nozzle head, In the case of including a linear moving unit that relatively linearly moves the mounting table and a rotating unit that relatively rotates the nozzle head and the mounting table, the rotating unit is relatively 180 to the nozzle head and the mounting table. It is preferable to be configured so that it can be reversed.

  In the phosphor layer forming method of the plasma display panel using such a phosphor layer forming apparatus, the phosphor paste application region of the substrate is divided into a plurality of small regions corresponding to the number of nozzles of the nozzle head, The first step of applying the phosphor paste by relatively moving the mounting table in the rib direction and the second step of reversing the nozzle head and the mounting table relatively 180 degrees are combined to fluoresce in the grooves of each small region. It becomes possible to apply body paste.

In this case, when the nozzle head has nozzles No. 1 to n in order from the end, the boundary between the small areas of the grooves applied in each of the small areas when the application operation of the two small areas is completed. It is preferable that the nozzle head and the mounting table are relatively inverted by 180 degrees so that the two grooves closest to each other with the first and the nth nozzles are the closest to each other.
As a result, the two grooves closest to each other across the boundary of the small region are applied by the same nozzle, so that extreme variation in the application amount at the boundary portion is suppressed.

  Further, when the phosphor paste is applied to the plurality of grooves of the first group and the nozzle head is inverted to apply the phosphor paste to the plurality of grooves of the second group, the grooves of the first group and the grooves of the second group The first step and the second step may be combined so that are alternately arranged. In this case, since the first group of grooves and the second group of grooves are alternately arranged, variation in the coating amount is averaged.

EXAMPLES Hereinafter, the present invention will be described in detail based on examples shown in the drawings. This does not limit the invention.
FIG. 2 is an explanatory view showing the configuration of the embodiment of the present invention. In this embodiment, the phosphor layer 28 is formed on the substrate 21 having the address electrodes A and the ribs r shown in FIG. An apparatus and a method for applying to the grooves between the ribs r will be described.

  In FIG. 2, the manipulator 1 is supported by the shaft 2 in the directions indicated by the arrows Y1, Y2 (Y) while the manipulator 1 moves up and down in the directions indicated by the arrows Z1, Z2 (Z-axis direction) while holding the shaft 2 horizontally. A Y-axis moving device 4 that slides in the axial direction), X-axis moving devices 5a and 5b that reciprocate the Z-axis moving devices 3a and 3b vertically (X-axis direction) with respect to the paper surface, and a substrate 21 are placed. A turntable 7 is provided. The nozzle head 51 is fixed to the handle 6 of the Y-axis moving device 4. The turntable 7 is rotated about a shaft 9 by a rotating device 8.

  A storage tank 52 for storing the phosphor paste is connected to a pressurized tank 56 via tubes 53 and 54 and an electromagnetic valve 55. A compressed air source (for example, an air compressor) 57 is connected to a pressurized tank 56 via a pressure regulator 61, an electromagnetic valve 62, and tubes 58, 59, 60, and a phosphor stored in the pressurized tank 56 from the storage tank 52. The paste is pressurized. The pressurized tank 56 is connected to the nozzle head 51 via an electromagnetic valve 63 and tubes 64 and 65.

  The suction (vacuum) device 70 is connected to both ends of the nozzle head 51 via tubes 66, 67, 68, sucks phosphor paste discharged from dummy nozzles and side nozzles described later, and stores the storage tank 52 via the tube 69. It has come to be collected.

3 is a front view of the nozzle head 51, and FIG. 4 is a cross-sectional view taken along the line AA in FIG.
In these drawings, the main body 80 includes therein a storage chamber 81 that stores the phosphor paste supplied from the tube 65, and 107 nozzles that project downward from the bottom surface of the main body 80 in communication with the storage chamber 81. N1 to N107 are arranged in a line at a pitch Pn. 3 to 20 dummy nozzles Nd are arranged at a pitch Pn on both sides of the row of nozzles N1 to N107, and all communicate with the storage chamber 81. Further, side nozzles Ns protrude from both side surfaces of the main body 80 and communicate with the storage chamber 81.

  Here, the nozzles N1 to N107 have a length of 15 mm, the outer diameter is 400 μm, the inner diameter is 200 μm, the dummy nozzle Nd has a length of 2 mm, the outer diameter is 400 μm, the inner diameter is 150 μm, and the side nozzle Ns has a length of 10 mm. The diameter is 500 μm and the inner diameter is 300 μm. Further, trays 82 and 83 for receiving phosphor paste discharged from the dummy nozzle Nd and the side nozzle Ns are installed at both ends of the main body 80 via brackets 82a and 83a, respectively. Tubes 66 and 67 are connected to each other.

  In addition, on the back surface of the main body 84, as shown in FIG. 4, three precipitation preventing devices 84 are exposed in the storage chamber 81 in order to prevent the fluorescent substance contained in the phosphor paste from being precipitated in the storage chamber 81. Is provided. Here, an ultrasonic oscillator (manufactured by Alex Trading Co., Ltd.) that oscillates at 40 KHz is used as the precipitation preventing device 84. In addition, the phosphor paste may be cooled by using a Peltier element in the precipitation preventing device 84 to increase its viscosity, thereby preventing precipitation.

  In such a configuration, the red phosphor paste is first applied to the grooves between the ribs r of the substrate 21 shown in FIG. In this embodiment, a substrate for a 42-inch PDP (panel size 980 mm × 580 mm) is used as the substrate 21, and 2569 ribs r (FIG. 1) are previously provided in parallel at a pitch Pr on the surface, thereby 2568. A groove of a book is formed.

Here, the rib pitch Pr is set to (1.08 / 3) mm, and the relationship between the nozzle pitch Pn and the rib pitch Pr is Pn = 6Pr.
Therefore, the substrate 21 shown in FIG. 2 is placed on the turntable so that the longitudinal direction of the ribs r is perpendicular to the paper surface. As shown in FIG. 6, the phosphor paste application region S of the substrate 21 is divided into four small regions S1 to S4 so that one small region has 6 × 10 7 grooves. Is started.

  The X-axis moving devices 5a and 5b, the Y-axis moving device 4, and the Z-axis moving devices 3a and 3b are driven to align the nozzles N1 to N107 and the rib r and adjust the gap between the nozzles N1 to N107 and the rib r. Do it. A part of the red phosphor paste previously stored in the storage tank 52 is supplied to the pressurized tank 56 by the operation of the valve 55, and then the air pressure is supplied from the compressed air source 57 via the pressure regulator 61 and the electromagnetic valve 62. Is applied to the pressurized tank 56. Therefore, when the electromagnetic valve 63 is opened, the phosphor paste is supplied to the nozzle head 51, and the nozzles N1 to N107 start discharging the phosphor paste to a predetermined groove between the ribs r as shown in FIG.

  At the same time, after the nozzle head 51 is advanced from the front end to the rear end of the rib r by the X-axis moving devices 5a and 5b, the electromagnetic valve 63 is closed and the discharge of the nozzles N1 to N107 is stopped. Thereby, the phosphor paste is applied to the 107 grooves with the pitch Pn, that is, the pitch 6Pr over the entire length. This completes the process indicated by the arrow (1) in FIG.

  Next, the Y-axis moving device 4 moves the nozzle head 51 by 3 Pr in the Y2 direction (FIG. 2). Next, while opening the electromagnetic valve 63 and discharging the phosphor paste from the nozzles N1 to N107, the nozzle head 51 is retracted from the rear end to the front end of the rib r by the X-axis moving devices 5a and 5b. Is closed to stop the discharge of the nozzles N1 to N107. This completes the process indicated by the arrow (2) in FIG.

  By repeating the application process as indicated by arrows (3) to (8) in FIG. 6, the red phosphor paste is applied to all the grooves in which the red phosphor layer is to be formed. Next, the phosphor pastes for green and blue are applied in the same manner using apparatuses equivalent to those shown in FIG. 2, and the application work of the three color phosphor pastes is completed.

  In the nozzle head 51 shown in FIG. 3, when the phosphor paste is ejected from the nozzles N1 to N107, the phosphor paste is also ejected from the dummy nozzle Nd and the side nozzle Ns at the same time. As a result, the phosphor paste at both ends of the storage chamber 81 of the nozzle head 51 flows, so that the flow resistance of the phosphor paste flowing from the storage chamber 81 to the nozzles N1 and N107 is substantially equal to the other nozzles N2 to N106. Therefore, the flow rates of the nozzles N1 to N107 are made uniform, and variations in the amount of phosphor paste applied are suppressed.

  Note that the dummy nozzle Nd and the phosphor paste discharged from the dummy nozzle Nd are received by the trays 82 and 83, sucked by the suction device 70 through the tubes 66, 67 and 68 (FIG. 2), and collected into the storage tank 52. Reused (recycled). Further, the nozzle head 51 of FIG. 3 includes both the dummy nozzle Nd and the side nozzle Ns, but only one of them may be used depending on the flow characteristics of the phosphor paste.

  3 and 4 is driven in a period in which the nozzles N1 to N107 do not discharge the phosphor paste, that is, in a rest period of the coating process, and the like. In 81, the fluorescent substance contained in the phosphor paste is vibrated to prevent its precipitation. As a result, the phosphor paste supplied from the storage chamber 81 to the nozzles N1 to N107 during the application operation always maintains a constant phosphor concentration.

  By the way, when the application process of the phosphor paste for red is performed as shown in FIG. 6, the side view of each boundary (part B in FIG. 6) of the small regions S1 to S4 is as shown in FIG. In FIG. 7, the applied paste layers P1 to P107 are formed by nozzles N1 to N107, respectively.

  In this case, the paste layers P1 and P107 are adjacent to each other with the boundary line L as a boundary. Therefore, when the nozzles N1 to N107 have discharge characteristics such that the discharge amount gradually changes from the nozzle N1 toward the N107, the difference in paste filling amount on both sides of the boundary line L is maximized, and as a result, the PDP Display unevenness, so-called non-uniformity, occurs at the boundary line L.

  In such a case, as a countermeasure, application work is performed in the order shown in FIG. However, the coating steps indicated by the arrows (5) to (8) are performed after the turntable 7 is rotated 180 degrees by the rotating device 8.

As a result, the enlarged side views of part C and part D in FIG. 8 are as shown in FIGS. 9 and 10, respectively. That is, the paste layers P1 and P1 or P107 and P107 are adjacent to each other with the boundary line L as a boundary. Therefore, the width of the paste layer is the same on both sides of the boundary line L, and uneven stripes in PDP display are prevented.
Moreover, you may perform an application | coating operation | work in the order as shown in FIG. However, the application steps indicated by arrows (5) to (8) are performed after the turntable 7 is rotated 180 degrees.

  Accordingly, the enlarged side view of the portion E in FIG. 11 becomes as shown in FIG. That is, in FIG. 12, the paste layers P1 to P107 and the paste layers P107 to P1 are alternately mixed, and in FIG. 13, P107 and P107 are adjacent to each other. Are mixed and mixed, the variation in paste filling amount is averaged, and unevenness in the display of the PDP is prevented.

It is a perspective view which shows the principal part structure of PDP which concerns on this invention. It is a configuration explanatory view showing an embodiment of the present invention. It is a front view of the nozzle head of this invention. It is AA arrow sectional drawing of FIG. It is explanatory drawing which shows the fluorescent substance paste application condition of this invention. It is a top view of the board | substrate of this invention. It is the B section enlarged side view of FIG. It is a top view of the board | substrate of this invention. It is the C section enlarged side view of FIG. It is the D section enlarged side view of FIG. It is a top view of the board | substrate of this invention. It is the E section enlarged side view of FIG. It is the E section enlarged side view of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Manipulator 2 Shaft 3a Z-axis moving device 3b Z-axis moving device 4 Y-axis moving device 5a X-axis moving device 5b X-axis moving device 6 Handle 7 Turntable 8 Rotating device 9 Shaft 51 Nozzle head 52 Storage tank 53 Tube 54 Tube 55 Electromagnetic valve 56 Pressurized tank 57 Compressed air source 58 Tube 59 Tube 60 Tube 61 Pressure regulator 62 Electromagnetic valve 63 Electromagnetic valve 64 Tube 65 Tube 66 Tube 67 Tube 68 Tube 69 Tube 70 Suction device 80 Main body 81 Storage chamber 82 Sauce pan 82a Bracket 83 Receptacle 83a Bracket 84 Precipitation prevention device N1 Nozzle N2 Nozzle N3 Nozzle N106 Nozzle N107 Nozzle Nd Dummy nozzle Ns Side nozzle

Claims (5)

  An apparatus for forming a phosphor layer by applying a phosphor paste to a groove formed between a plurality of ribs provided on the surface of a substrate, and placing a substrate on which the substrate is placed, and discharging the phosphor paste A nozzle head in which a plurality of nozzles arranged in a row, a supply unit for supplying a phosphor paste to the nozzle head, a linear moving unit that relatively linearly moves the nozzle head and the mounting table, a nozzle head and a mounting table, A phosphor layer forming apparatus for a plasma display panel, comprising: a rotating unit that relatively rotates the rotating unit.   2. The phosphor layer forming apparatus for a plasma display panel according to claim 1, wherein the rotating unit is configured to be able to reverse the nozzle head and the mounting table by 180 degrees relative to each other.   A phosphor layer forming method for a plasma display panel using the phosphor layer forming apparatus according to claim 1, wherein the phosphor paste application region of the substrate is divided into a plurality of small regions corresponding to the number of nozzles of the nozzle head. The first step of applying the phosphor paste by moving the nozzle head and the mounting table relative to each other in the rib direction and the second step of reversing the nozzle head and the mounting table relatively by 180 degrees are combined with each small region. A method for forming a phosphor layer of a plasma display panel, wherein a phosphor paste is applied to the groove.   When the nozzle head has nozzles from No. 1 to No. n in order from the end, when the application work of the two small areas is finished, the boundary between the small areas is sandwiched between the grooves applied in each small area. 4. The plasma according to claim 3, wherein the first step and the second step are combined so that the two closest grooves are both grooves applied by the same nozzle of No. 1 or No. n. A method for forming a phosphor layer of a display panel.   When the phosphor paste is applied to the plurality of grooves of the first group and the nozzle head is reversed to apply the phosphor paste to the plurality of grooves of the second group, the grooves of the first group and the grooves of the second group are 4. The method for forming a phosphor layer of a plasma display panel according to claim 3, wherein the first step and the second step are combined so as to be alternately arranged.

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