JP2009289520A - Method for manufacturing plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a plasma display panel that can display high-quality images by forming an excellent phosphor layer in forming the phosphor layer between barrier ribs by a so-called dispenser method. <P>SOLUTION: The method for manufacturing the plasma display panel comprises a step of forming the phosphor layer 35 by scanning while discharging phosphor paste 73 from a nozzle hole 72 to fill and apply the phosphor paste 73 to an electric discharge cell 51. The discharge side 72a of the nozzle hole 72 inclines to the rear side with respect to a scanning direction 60. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a plasma display panel known as a display device.

  In recent years, expectations for large screens and wall-mounted televisions have increased as interactive information terminals, and there are many display devices such as plasma display panels, liquid crystal display panels, field emission displays, and electroluminescence displays.

  Among these display devices, a plasma display panel (hereinafter referred to as “PDP”) is a thin display device with excellent visibility because it is self-luminous, can display beautiful images, and is easy to enlarge. Development for high definition and large screen is underway.

  A PDP has a minute discharge between a front plate on which components such as a display electrode, a dielectric layer, and a protective layer made of MgO are formed, and a back plate on which components such as address electrodes, barrier ribs, and phosphor layers are formed. The cells are arranged so as to face each other and the periphery is sealed with a sealing member.

A discharge gas in which neon (Ne), xenon (Xe), or the like is mixed is sealed in the discharge cell at a pressure of, for example, about 66500 Pa (about 500 Torr) (see Patent Document 1).
JP 2003-131580 A

  Even in this large-screen PDP, high definition is indispensable, and with the miniaturization of discharge cells, new problems that have not occurred in conventional PDPs have arisen.

  One of them is that the phosphor paste is ejected through a hole narrower than the cell width to generate a coating flow, and in that state, the phosphor paste is scanned between the barrier ribs by scanning from one end to the other end of the barrier ribs. In the phosphor layer forming process by the so-called dispenser method, the coating state becomes non-uniform due to disturbance of the coating flow, etc. This is a problem that “bubble bubbles” and the like are generated.

  The present invention has been made in view of such a current situation, and in forming a phosphor layer between partition walls by a so-called dispenser method, a good phosphor layer can be formed, and thus a PDP capable of displaying a high-quality image. It aims at realizing the manufacturing method of.

  To achieve the above object, a PDP manufacturing method of the present invention includes a step of forming a phosphor layer by filling and applying a phosphor paste to a discharge cell by scanning while discharging the phosphor paste from a nozzle hole. The nozzle hole is characterized in that its discharge side is inclined rearward with respect to the scanning direction.

  According to the present invention, when forming a phosphor layer between partition walls by a dispenser method, a favorable phosphor layer can be formed, and thus a method for manufacturing a PDP capable of displaying a high-quality image can be realized.

  Hereinafter, a method for manufacturing a PDP according to an embodiment of the present invention will be described with reference to the drawings.

  First, the structure of the PDP will be described with reference to FIG. FIG. 1 is a cross-sectional perspective view showing a schematic structure of a PDP. As shown in FIG. 1, the PDP 10 includes a front plate 20 and a back plate 30, and the front plate 20 and the back plate 30 are arranged to face each other so as to form a discharge space. In the front plate 20, a plurality of stripe-shaped display electrodes 24 that are paired with a scanning electrode 22 and a sustain electrode 23 are formed on a front glass substrate 21. A black stripe 25 serving as a light shielding layer is formed between adjacent display electrodes 24. A dielectric layer 26 is formed so as to cover the display electrode 24 and the black stripe 25, and a protective layer 27 made of magnesium oxide (MgO) is further formed so as to cover the dielectric layer 26.

  The back plate 30 has an address electrode 32 formed on the back glass substrate 31 in a direction orthogonal to the display electrode 24 of the front plate 20, and a base dielectric layer 33 is provided to cover the address electrode 32. On the base dielectric layer 33, there are provided barrier ribs 34 formed in a grid pattern by vertical barrier ribs 34 a in a direction parallel to the address electrodes 32 and horizontal barrier ribs 34 b in a direction orthogonal to the address electrodes 32. A phosphor layer 35 is provided on the side surfaces of the first and second base dielectric layers 33. In the discharge space 40 partitioned by the adjacent barrier ribs 34, the phosphor layer 35 has a red phosphor layer that emits red light for each address electrode 32, a green phosphor layer that emits green light, and a blue phosphor layer that emits blue light. Are formed in order.

  The front plate 20 and the back plate 30 are arranged to face each other so that the display electrodes 24 and the address electrodes 32 intersect, and the peripheral portions thereof are sealed and joined with a sealing material. The discharge space 40 is filled with, for example, a mixed gas of neon (Ne) and xenon (Xe) as a discharge gas.

  Then, by selectively applying a video signal voltage to the display electrode 24, the discharge gas is discharged, and the ultraviolet rays generated thereby excite the phosphor layers 35 of each color to emit red, green, and blue colors. As a result, a color image is displayed.

  As shown in FIG. 1, the vertical partition wall 34a and the horizontal partition wall 34b have different partition wall heights and the horizontal partition wall 34b is lower than the vertical partition wall 34a. Alternatively, it may be a stripe shape with only vertical barrier ribs, or it may be in the form of a grid with the same vertical and horizontal height.

  FIG. 2 is a plan view of the PDP as viewed from the front glass substrate 21 (FIG. 1) side of the front plate 20 (FIG. 1). The display electrode 24 paired with the scan electrode 22 and the sustain electrode 23 (22a and 23a are transparent electrodes made of ITO or the like, and 22b and 23b are bus electrodes made of a metal material such as Ag) are discharged. They are arranged with a gap 50 in between. In addition, a rectangular region defined by the vertical barrier ribs 34a and the horizontal barrier ribs 34b and intersecting the display electrodes 24 and the address electrodes 32 constitutes a discharge cell 51 as a unit light emitting region. In the discharge cells 51, a non-discharge region 52 is formed between adjacent discharge cells 51, that is, between adjacent display electrodes 24, and a light shielding layer 25 for improving contrast is formed on the front glass substrate 21 in this region. Therefore, the horizontal barrier rib 34b is formed in the non-discharge region 52, and the light shielding layer 25 is formed at a position corresponding to the horizontal barrier rib 34b.

  Here, as a method of forming the phosphor layer 35 for each of the RGB cells, generally, a method (printing method) in which phosphor paste containing phosphor powder, resin, and solvent is filled and applied to each cell by printing. In addition, the method of filling and applying by discharging from a smaller hole than each cell (dispenser method) can be mentioned, but while the cell size is miniaturized with the high definition of PDP, In principle, it is difficult to ensure accuracy, and the dispenser method is more advantageous. Accordingly, the PDP manufacturing method according to one embodiment of the present invention described below is intended for a dispenser system.

  In this dispenser system, as schematically shown in a cross-sectional view in FIG. 3, the phosphor paste 73 is discharged from a nozzle hole 72 having a diameter smaller than the width of the discharge cell 51 provided in the nozzle 71 and parallel to the vertical partition wall 34a. In this method, the phosphor layer 35 is formed by filling each cell with the phosphor paste 73 by scanning in any direction. In this method, as shown schematically in FIG. (The cross-sectional view shown in FIG. 4 is in a direction perpendicular to the cross-sectional view shown in FIG. 3), and the application flow of the phosphor paste 73 collides with the horizontal barrier ribs 34b, and the application flow is disturbed. In some cases, the formed phosphor layer 35 has a problem that defects such as coating omission 73a and bubble smear 73b occur. Such a problem is particularly prominent in fine cells with high definition (full HD).

  Therefore, the PDP manufacturing method according to an embodiment of the present invention has a diameter narrower than the cell width defined by the vertical partition wall 34a adjacent to the nozzle 71, as shown in a schematic sectional view in FIG. A nozzle hole 72 is formed, and the phosphor paste 73 is discharged from the substrate 31 and scanned from one end of the substrate 31 to the other end along the vertical barrier ribs 34a. In the manufacturing method for forming the layer 35, the nozzle hole 72 is inclined with respect to the phosphor paste application traveling direction 60. More specifically, the discharge side 72 a of the nozzle hole 72 is formed with respect to the application traveling direction. It is characterized by tilting backward.

  Here, the following can be considered as one of the causes of defects such as coating omission in the phosphor layer 35 formed in the discharge cell 51. That is, when the phosphor paste 73 is applied by scanning from one end of the substrate 31 to the other end while being ejected from the nozzle hole 72, the application flow of the phosphor paste 73 is spread and ejected from the nozzle hole 72 toward the substrate. Therefore, if the distance between the nozzle hole 72 and the substrate is not properly maintained, the width of the coating flow exceeds the cell width defined by the adjacent vertical barrier ribs, and the phosphor paste 73 rides on the top of the vertical barrier ribs 34a. The problem that it will end up occurs.

  On the other hand, in order to reduce the occurrence of the above problem, it is effective to bring the discharge side 72a of the nozzle hole 72 close to the top of the partition wall 34, but if it is too close, the impact when the coating flow collides with the horizontal partition wall 34b will occur. For this reason, bounce and scatter occur, which adheres to the vicinity of the discharge side 72a of the nozzle hole 72 on the lower surface of the nozzle 71, hits the discharge flow of the phosphor paste 73, and the coating flow is interrupted. For example, the discharge flow of the phosphor paste 73 may become unstable. In such a case, a problem occurs in the filling / application state of the phosphor paste in the discharge cells 51.

  For this reason, the coating conditions should be such that a sufficient margin can be secured for the distance (clearance) between the nozzle hole 72 and the top of the partition wall 34, but this margin becomes smaller as the discharge cells become finer with higher definition. As a result, the above-mentioned problems have occurred as a result.

  On the other hand, according to the PDP manufacturing method according to the embodiment of the present invention as described above, the discharge side 72a of the nozzle hole 72 is inclined rearward with respect to the coating traveling direction. Since the nozzle hole 72 is inclined and provided so as to flow backward along the coating traveling direction 60, it is possible to greatly reduce the occurrence of the above-described problems, and the above-described margin for coating is expanded. be able to.

  That is, as shown in the cross-sectional view of the schematic configuration in FIG. 6, according to the PDP manufacturing method according to the embodiment of the present invention shown in FIG. Therefore, the central axis of the nozzle hole 72 and the horizontal partition wall 34b have an angle. Therefore, in the case of the conventional method for manufacturing a PDP shown in FIG. Thus, compared with the case where the central axis of the nozzle hole 72 and the partition are parallel and the flow direction of the coating flow of the phosphor paste 73 is parallel to the lateral partition 34b, the phosphor paste 73 and the lateral partition 34b are compared. As a result, the impact is relieved and the impact is alleviated, and the discharge flow of the phosphor paste 73 becomes unstable due to rebound, scattering, and interruption of the coating flow. Because Considered.

  In addition, as a method of manufacturing a PDP according to another embodiment of the present invention, for example, as shown in a schematic cross-sectional view in FIGS. 7 and 8, the nozzle hole 72 has a diameter of the discharge side 72a and the opposite side (upstream). As a result, the central axis of the nozzle hole 72 and the horizontal partition wall 34b have an angle. As a result, the flow direction of the coating flow of the phosphor paste 73 is set to an angle θ with respect to the horizontal partition wall 34b. It may be configured to have.

  In such a configuration, it is possible to increase the discharge pressure of the phosphor paste and increase the amount of application, so that it is possible to obtain an effect that the tact can be reduced.

  Here, the shape of the discharge side 72a of the nozzle hole 72 may be circular as long as the above relationship is satisfied, but it is a hole smaller than the width between the adjacent vertical partition walls 34a in order to suppress climbing to the top of the vertical partition wall 34a. Therefore, as shown in FIG. 9, an example of a schematic configuration is preferable, and a shape such as a large ellipse having a diameter extending along the coating traveling direction 60 or a polygon is preferable.

  Further, as shown in FIG. 10, the manufacturing method of the PDP according to another embodiment of the present invention has the same nozzle configuration as that of the conventional one, and the nozzle is tilted with respect to the coating traveling direction 60 to phosphor. By applying the paste, an angle is given to the central axis of the nozzle hole 72 and the horizontal partition wall 34b, and as a result, the flow direction of the application flow of the phosphor paste 73 is set to an angle θ with respect to the horizontal partition wall 34b. It may be configured as follows.

  Although FIG. 10 shows the case where the nozzle is tilted, the same effect can be obtained by tilting the substrate with respect to the nozzle. In the case of the above embodiment, since it can be implemented using a conventional nozzle, introduction is easy.

  As described above, the present invention is useful for providing a large-screen, high-definition plasma display device.

1 is a cross-sectional perspective view showing a schematic structure of a PDP according to an embodiment of the present invention. The top view which looked at PDP by one embodiment of this invention from the front glass substrate side of the front plate Schematic cross-sectional view for explaining a general dispenser system Schematic cross-sectional view for explaining a general dispenser system Sectional drawing which shows schematically the manufacturing method of PDP by one embodiment of this invention Sectional drawing which shows schematically the manufacturing method of PDP by one embodiment of this invention Sectional drawing which shows schematically the manufacturing method of PDP by other embodiment of this invention. Sectional drawing which shows schematically the manufacturing method of PDP by other embodiment of this invention. The figure which shows schematically the manufacturing method of PDP by other embodiment of this invention. Sectional drawing which shows schematically the manufacturing method of PDP by other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Plasma display panel 20 Front plate 21 Front glass substrate 22 Scan electrode 22a, 23a Transparent electrode 22b, 23b Bus electrode 22 Scan electrode 23 Sustain electrode 24 Display electrode 25 Light shielding layer 26 Dielectric layer 27 Protective layer 30 Back plate 31 Back glass substrate 32 Address electrode 33 Base dielectric layer 34 Partition 34a Vertical partition 34b Horizontal partition 35 Phosphor layer 40 Discharge space 50 Discharge gap 51 Discharge cell 52 Non-discharge region 60 Scan direction 71 Nozzle 72 Nozzle hole 73 Phosphor paste

Claims (1)

A method of manufacturing a plasma display panel comprising a step of forming a phosphor layer by filling and applying to a discharge cell by scanning while discharging a phosphor paste from a nozzle hole. A method of manufacturing a plasma display panel, wherein the plasma display panel is inclined rearward with respect to a scanning direction.

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