Patent Publication Number: US-7722420-B2

Title: Manufacturing method of a plasma display panel having a base layer along a first direction and a phosphor layer along a second direction that intersects the first direction

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a display panel and a manufacturing method of the display panel. 
   2. Description of Related Art 
   Conventionally, a plasma display panel (PDP) has been configured by: disposing a pair of planar substrates to face each other with a discharge space interposed therebetween; partitioning the discharge space into a plurality of discharge cells by providing a curb-shaped or striped partition on an inner surface of one of substrates; and providing the partitioned portions with phosphor layers exemplarily of red, blue and green. The PDP displays images by selectively discharging inside the discharge cells for light emitting. As a method for forming the phosphor layer in the PDP, there has been know an ink-jet method, with which a phosphor material is injected to between the partitions using, for example, a nozzle (e.g. see Document: JP-A-2002-75216). 
   According to a manufacturing method of a plasma display panel (PDP) disclosed in Document, an address electrode is formed on a rear panel substrate, partitions are formed on the address electrode with a pitch of a predetermined value, and a phosphor layer is formed between the partitions. The phosphor layer according to the manufacturing method of the PDP is formed using an ink ejecting device that ejects phosphor ink. A plurality of nozzle bodies of the ink ejecting device, each of which includes a nozzle and a header, are fixed to a fixing table. A supply pipe for supplying the phosphor ink from a pressurizing supply unit is connected to the header while a nozzle-flow-rate controlling valve provided to the nozzle controls a flow rate of the phosphor ink ejected from the nozzle. In the manufacturing method of the PDP, the ejecting amount of the nozzle is measured before the phosphor ink is applied, and the flow rate of the nozzle is variably controlled per one scanning, thereby preventing a column variation. 
   However, according to the method in which the nozzle ejects the phosphor ink for forming the phosphor layer, an error in an opening dimension of the nozzle may cause a difference in the ejecting amount of the phosphor ink, which can lead to a difference in a thickness of the phosphor layer. When there is an error in the opening dimension of the nozzle, a difference as much as the fourth power of the error value of the nozzle opening is caused in the thickness of the phosphor layer. 
   Although such a conventional manufacturing method of a PDP as disclosed in the above Document may be used for solving such problems, the conventional manufacturing method of the above Document requires a detector for detecting the ejecting amount of the nozzle and a complex control program for controlling the flow rate of the nozzle by a controller, which leads to a complication of a configuration. 
   Another possible arrangement is to thin the phosphor layer so as to reduce variations of the thickness, thereby suppressing a column variation. However, since the thickness of the phosphor layer is generally specified by a panel standard for a display panel, a realization of the arrangement may be difficult. 
   Another possible arrangement is to provide a base layer by printing between the phosphor layer and the substrate and to form the phosphor layer on the base layer, thereby reducing the thickness dimension of the phosphor layer. However, when the base layer is printed, a variation can be caused in a thickness dispersion, which can lead to a luminance variation. 
   SUMMARY OF THE INVENTION 
   In light of the above-described problems, an object of the present invention is to provide a display panel that is easily manufacturable and realizes good images, and a manufacturing method for the display panel. 
   A display panel according to an aspect of the present invention includes: a pair of substrates disposed to face each other with a discharge space being interposed; a plurality of partitions that partition the discharge space, the partitions being provided to at least one of the substrates substantially along a predetermined first direction; a phosphor layer provided between the partitions that neighbor each other substantially along the first direction; and a base layer provided to the at least one of the substrates along a second direction intersecting the first direction, in which the base layer is disposed between the phosphor layer and the at least one of the substrates. 
   A manufacturing method of a display panel according to another aspect of the present invention is a method for manufacturing a display panel that includes: a pair of substrates disposed to face each other with a discharge space interposed; a plurality of longitudinal partitions that partition the discharge space, the partitions being provided to at least one of the substrates substantially along a predetermined first direction; and a phosphor layer provided between the partitions that neighbor each other substantially along a longitudinal direction of the partitions, the method including: a partition forming step to form the partitions on the at least one of the substrates; a base layer forming step to form a base layer by moving a first nozzle along a direction intersecting the longitudinal direction of the partitions formed in the partition forming step and applying a base forming agent on the at least one of the substrates using the first nozzle, the first nozzle being adapted to apply the base forming agent; and a phosphor layer forming step to form the phosphor layer after the base layer forming step by moving a plurality of second nozzles along the longitudinal direction of the partitions and between the partitions that neighbor each other and applying a phosphor paste on the base layer, the second nozzle being adapted to apply the phosphor paste. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded perspective view showing a plasma display panel according to an embodiment of the present invention; 
       FIG. 2A  is a side cross-sectional view showing a rear substrate in a base layer forming step according to the embodiment; 
       FIG. 2B  is a plan view showing the rear substrate in the phosphor layer forming step according to the embodiment; 
       FIG. 3A  is a side cross-sectional view showing the rear substrate in a phosphor layer forming step according to the embodiment; and 
       FIG. 3B  is a plan view showing the rear substrate in the phosphor layer forming step according to the embodiment. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENT(S) 
   A first embodiment of the present invention will be described below with reference to the attached drawings. 
   [Arrangement of Plasma Display Panel] 
     FIG. 1  is a perspective view showing a substrate of a plasma display panel according to the first embodiment of the present invention. 
   In  FIG. 1 , the numeral  100  refers to a plasma display panel serving as a display panel, and the plasma display panel (PDP)  100  is shaped in a substantially rectangular plate. 
   As shown in  FIG. 1 , in the PDP  100 , a front substrate  110  and a rear substrate  120  are disposed to face each other with a discharge space provided therebetween. 
   In an inner side of the front substrate  111 , a plurality of display electrodes  111 , a plurality of black stripes  112 , a dielectric layer  113  and a protective layer  114  are provided. 
   Specifically, the display electrode  111  includes: plural pairs of transparent electrodes  111 A,  111 B that face each other with a discharge gap G therebetween; and a pair of linear bus electrodes (not shown) laminated on one ends of the transparent electrodes  111 A,  111 B. The transparent electrodes  111 A,  111 B are each a transparent conductive film that is formed of, for example, ITO (Indium Tin Oxide) or the like, and each pair of transparent electrodes  111 A,  111 B is provided to correspond to a discharge cell serving as a predetermined display cell. 
   The bus electrodes, which are linearly formed of, for example, Ag (silver) or the like, are laminated on the ends of the pair of transparent electrodes  111 A,  111 B, the ends being on sides opposite to the discharge gap G. One ends of the bus electrodes are provided with bus electrode leading portions (not shown), through which a voltage pulse from a row electrode driver (not shown) is applied to the transparent electrodes  111 A,  111 B. 
   The black stripe  112  is linearly formed of, for example, a black inorganic pigment or the like. The black stripe  112  absorbs visible light irradiated from the outside of the front substrate  110 . 
   The dielectric layer  113 , which is formed of, for example, a dielectric paste or the like, is arranged to face an address-electrode dielectric layer  122  of the rear substrate  120 . When the panel is driven, the dielectric layer  113  prevents the display electrodes  12  from being damaged by the discharge panel and accumulates electric charges required for the drive. 
   The protective layer  114 , which is a transparent layer that is formed of MgO (magnesium oxide) by vapor deposition, sputtering or the like, covers the entire inner surface of the dielectric layer  113 . The protective layer  114  prevents the dielectric layer  113  from being sputtered due to the discharge while serving as a discharge layer of a secondary electron for generating the discharge at a low voltage. 
   The rear substrate  120 , which is a rectangular glass plate, includes an address electrode  121 , the address-electrode dielectric layer  122 , a partition layer  123 , a base layer  126 , a phosphor layer  127  and the like. 
   The address electrode  121  is provided in plurality in parallel to, for example, a width direction of the rear substrate  120 , thereby forming zonal patterns. The address electrode  121  is formed of, for example, a thin film of Aluminum (Al) by photolithography or the like. In addition, both ends of the address electrode  121  are provided with a leading electrode (not shown) for guiding a predetermined signal to the address electrode  121 , the leading electrode being drawn outward from an end periphery of the address-electrode dielectric layer  122 . 
   The address-electrode dielectric layer  122  is formed exemplarily of glass paste to protect the address electrode  121 . The address-electrode dielectric layer  122  is provided on the inner side of the rear substrate  120  to cover the address electrode  121 . 
   The partition layer  123  is formed exemplarily of the glass paste containing the same components as the glass paste forming the address-electrode dielectric layer  122  and provided on a surface facing the front substrate  110 . As shown in  FIG. 1 , the partition layer  123  includes: a plurality of first partitions  124  provided substantially along the width direction (a first direction) of the PDP  100 ; and a plurality of second partitions  125  provided substantially along a column direction (a second direction), which is perpendicular to the width direction. A recessed portion  123 A is defined by the first partitions  124  and the second partitions  125 . Particularly, the recessed portion  123 A is provided to a portion where the first groove defined by the neighboring first partitions  124  to be located therebetween is superposed on a second groove defined by the neighboring second partitions  125  to be located therebetween. A height dimension of the second partition  125  from a surface of the address-electrode dielectric layer  122  is smaller than that of the first partition  124 . 
   As shown in  FIG. 1 , the base layer  126  is formed on the address-electrode dielectric layer  122  to stay within the recessed portions  123 A of the partition layers  123 . 
   The base layer  126  preferably has a reflection rate of 80 percent or more in a visible light region, and the base layer  126  is preferably chemically stable under a temperature of 200° C. or less. A particle size of a base-forming agent for forming the base layer  126  is preferably equal to or less than a particle size of a phosphor contained in a phosphor paste for forming the later-described phosphor layer  127 . Specifically, as the base-forming agent for forming the base layer  126 , powder of an oxide such as SiO 2 , TiO 2 , ZrO 2 , ZnO 2  and the like is preferably used. 
   A thickness dimension of the base layer  126  is not specifically limited, but is preferably substantially equal to a thickness dimension of the later-described phosphor layer (i.e., a half of the summed thickness of the base layer  126  and the phosphor layer  127 ). Although the thicknesses of the base layer  126  and the phosphor layer  127  are generally limited by properties required in the PDP  100  such as a substrate reflection rate and a luminescence rate of the phosphor layer  127 , a good substrate reflection rate and a good luminescence rate of the phosphor layer  127  can be realized by substantially equalizing the thicknesses of the base layer  126  and the phosphor layer  127  as described above. 
   The phosphor layer  127  is continuously provided in a first groove between the neighboring first partitions  124  to longitudinally extend along the longitudinal direction of the first partition  124  (the width direction of the PDP  100 ). 
   Specifically, the phosphor layer  127  includes a red phosphor layer  127 R, a green phosphor layer  127 G and a blue phosphor layer  127 B. As shown in  FIG. 1 , each of the phosphor layers  127 R,  127 G,  127 B are allayed in plurality in the longitudinal direction of the second partition  124  in the order of the red phosphor layer  127 R, the green phosphor layer  127 G and the blue phosphor layer  127 B. The phosphor layers  127 R,  127 G,  127 B are continuously provided along the first groove between the first partitions  124 . 
   [Manufacturing Method of Plasma Display Panel] 
   Next, a manufacturing method of the above-described PDP  100  will be described. 
     FIG. 2A  is a side cross-sectional view showing the rear substrate in the base layer forming step while  FIG. 2B  is a plain view showing the rear substrate in the base layer forming step.  FIG. 3A  is a side cross-sectional view showing the rear substrate in the phosphor layer forming step while  FIG. 3B  is a plain view showing the rear substrate in the phosphor layer forming step. 
   The manufacturing method of the PDP  100  according to the present embodiment includes: a front substrate manufacturing step for manufacturing the front substrate  110 ; a rear substrate manufacturing step for manufacturing the rear substrate  120 ; and a superposing step for superposing the front substrate  110  and the rear substrate  120  to manufacture the PDP  100 . 
   In the front substrate manufacturing step, a transparent-electrode-forming material layer is provided on the entirety of the inner side of the front substrate  110 , and the transparent electrodes  111 A,  111 B are formed. Then, linear patterns formed of Ag material are laminated on ends of the transparent electrodes  111 A,  111 B, and the bus electrodes is formed by calcination of the patterns. Subsequently, a paste pattern of a black inorganic pigment is exemplarily applied between the bus electrodes, whereby the plurality of black stripes  112  are formed by calcination of the paste pattern. Then, a dielectric paste is applied to the front substrate  110  in laminae, whereby the dielectric layer  113  is formed by calcination of the dielectric paste. The protective layer  134  is film-formed on the dielectric layer  113  by vapor deposition, sputtering or the like. 
   Next, the rear substrate manufacturing step is performed. The rear substrate manufacturing step includes an address electrode forming step, a dielectric layer forming step, a partition forming step, the base layer forming step and the phosphor layer forming step. 
   In the address electrode forming step, the address electrode  121  is formed on the rear substrate  120 . In the dielectric layer forming step, the address-electrode dielectric layer  122  is formed to cover the address electrode  121 . 
   In the partition forming step, a partition-forming material layer is uniformly applied to the address-electrode dielectric layer  122 . Then, a film molding die is exemplarily disposed on the partition-forming material layer, and the partition layer  123  is formed by plastic-deforming the partition-forming material layer using a transfer roller. The molding die has convexes and concaves of predetermined dimensions that correspond to the first partition  124 , the second partition  125  and the recessed portion  123 A. By plastic-deforming the partition-forming material layer by the transfer roller, there is provided the partition layer  123  including: the first partition  124  extending in the width direction; the second partition  125  extending in the column direction; and the partition end layer  123  having the recessed portion  123 A defined by the first partition  124  and the second partition  125 , as described above. 
   In the base layer forming step, the base-forming agent in paste form is applied on the partition layer  123  of the rear substrate  120  using a base-forming-agent applying nozzle  200  (a first nozzle) shown in  FIGS. 2A and 2B  to form the base layer  126  thereon. The nozzle  200  is adapted to be moved by a base-nozzle scanning mechanism (not shown) in the longitudinal direction of the second partition  125 , i.e., the column direction of the PDP  100 . Although the nozzle  200  is singularly provided in an arrangement shown in  FIGS. 2A and 2B , the plurality of nozzles  200  are provided to be movable by the base-nozzle scanning mechanism in an actual arrangement (i.e., a multi-nozzle method), so that the base-forming agent can be simultaneously applied to a plurality of lines. 
   Specifically, as shown in  FIG. 2A , the nozzle  200  is positioned at a first end of the second groove formed between the second partitions  125  (a first end of the PDP  100  in the column direction) in an initial state of the base layer forming step. Then, the nozzle  200  is moved from the position of the initial state to a second end of the second groove along the longitudinal direction of the second partition  125  at a predetermined constant speed, passing above the second groove. At this time, as shown in  FIG. 2B , the nozzle  200  ejects and applies the base-forming agent  201  along the second groove between the second partitions  125 . The applied base-forming agent  201 , which is pasty as described above, spreads within the recessed portion  123 A with a uniform thickness dimension maintained. 
   With respect to the base-forming agent  201  ejected from the nozzle  200 , an amount of the base-forming agent  201  ejected by the nozzle  200  and a movement speed of the nozzle  200  are set such that the thickness of the to-be-formed base layer  126  is substantially equalized to the thickness of the phosphor layer  127  (12.5 μm in the present embodiment). 
   Then, after the base-forming agent is filled in the recessed portions  123 A, the base layer  126  is calcinated by heat treatment. 
   In the phosphor layer forming step, the phosphor layer  127  is formed by applying the phosphor paste. In applying the phosphor paste, a phosphor applying device  300  adapted to inject the phosphor paste is used as shown in  FIGS. 3A and 3B . The phosphor applying device  300  is adapted to be moved by a phosphor-nozzle scanning mechanism (not shown) in the longitudinal direction of the first partition  124 , i.e., the width direction of the PDP  100 . The phosphor applying device  300  includes a plurality of phosphor applying nozzles  310  (second nozzles). 
   The phosphor applying nozzles  310  are positioned at a first end of the first groove between the first partitions  124  when the phosphor applying is started. Then, the nozzle  310  is moved from the position of the initial state to a second end of the first groove along the longitudinal direction of the first partition  124  at a predetermined constant speed, passing above the first groove. At this time, as shown in  FIG. 3B , the nozzle  310  ejects to apply the phosphor paste  301  along the first groove between the first partitions  124 . As shown in  FIG. 1 , the phosphor applying device  300  applies phosphor pastes of different colors to the neighboring first grooves. For instance, the phosphor applying device  300  applies the phosphor pastes such that a red phosphor paste for forming a red phosphor layer  127 R, a green phosphor paste for forming a green phosphor layer  127 G and a blue phosphor paste for forming a blue phosphor layer  127 B are applied to be aligned in the neighboring first grooves in this order. 
   Thereafter, a heat-treating step for heat-treating the applied phosphor paste  301  is performed, such that the phosphor layer  127  is formed by calcination. 
   Subsequently, by performing the superposing step, the front substrate  110  and the rear substrate  120  are superposed to manufacture the PDP  100 . 
   [Effects and Advantages of Plasma Display Panel] 
   According to the above-described arrangement according to the present embodiment, the following effects and advantages are expected. 
   (1) In the manufacturing method of the PDP  100  according to the present embodiment, the first partition  124  and the second partition  125  substantially perpendicular to the first partition  124  are formed on the address-electrode dielectric layer  122  of the rear substrate  120  in the partition forming step, such that the recessed portion  123 A corresponding to the display cell is formed. After the partition forming step, the nozzle  200  is moved along the second groove formed between the second partitions  125  to form the base layer  126  by applying the base-forming agent  201  in the base layer forming step. After the base layer forming step, the phosphor applying nozzle  310  is moved along the first groove formed between the first partitions  124  to form the phosphor layer  127  by applying the phosphor agent  301  in the phosphor layer forming step. 
   With this arrangement, since the base-forming agent is applied in a direction substantially perpendicular to a direction in which the phosphor paste  301  is applied, the thickness of the base layer  126  formed in a first recessed portion  123 A is substantially equalized to the thickness of the base layer  126  formed in a second recessed portion  123 A that neighbors the first recessed portion  123 A along the first groove. Accordingly, when the phosphor paste  301  is applied on the base-forming agent in the phosphor layer forming step, the difference in the summed thickness of the base layer  126  and the phosphor layer  127  between the neighboring first grooves is reduced, whereby a column variation and a luminance variation between the phosphor layers  127  on the neighboring first grooves can be favorably prevented. In addition, since the phosphor layer  127  is formed on the surface of the base layer  126 , the thickness of the phosphor layer  127  can be reduced as compared to an arrangement in which the phosphor layer  126  is formed without forming the base layer  126 . Accordingly, even when, for example, a manufacturing error is caused in a diameter dimension of an opening of the phosphor applying nozzle  310 , the difference in the thickness of the phosphor layer  127  due to the error in the diameter dimension of the opening is not increased, thereby preventing the column variation and the luminance variation. 
   In the base layer forming step and the phosphor layer forming step, the base-forming-agent applying nozzle  200  and the phosphor applying nozzle  310  are used to apply the base-forming agent  201  and the phosphor paste  301 . When the base-forming agent  201  and the phosphor paste  301  are applied using the nozzles, a variability of the applied agent and paste in advancing directions of the nozzles (applying directions) is generally reduced. Thus, by applying the base-forming agent  201  and the phosphor paste  301  using the nozzles as in the present embodiment, the variability of the applied agent and paste in the applying directions can be prevented, thereby favorably preventing the column variation and the luminance variation. 
   As described above, since the quality of the manufactured PDP  100  can be maintained at a constant level by preventing the column variation and the luminance variation, a quality control can be facilitated. 
   In addition, by simply moving the nozzle  200  along the longitudinal direction of the second partition  125  such that the base-forming agent  201  is ejected, the base-forming agent  201  can be easily applied. Likewise, by simply moving the phosphor applying device  300  along the longitudinal direction of the first partition  124  such that the phosphor applying nozzle  310  ejects the phosphor paste  301 , the phosphor paste  301  can be easily applied. Accordingly, a manufacturing process and a quality control for the PDP  100  can be facilitated. 
   (2) The base layer  126  is formed on the partition layer  123  of the rear substrate  120  using the plurality of the base-forming-agent applying nozzles  200  in the base layer forming step. 
   With this arrangement, the base-forming agent can be simultaneously applied along the plurality of second grooves, whereby rapid operations in the base layer forming step can be realized. Even when there is a manufacturing error in the diameter dimensions of the openings of the plural nozzles  200 , the same amount of the base-forming agent  201  can be applied to the recessed portions  123 A neighboring each other along the first groove, whereby the thicknesses of the phosphor layers  127  in the neighboring first grooves can be uniformed. Thus, even when the base-forming agent is simultaneously applied along the plurality of second grooves using the plurality of nozzles  200 , the column variation and the luminance variation of the PDP  100  can be prevented. 
   (3) The phosphor pastes of different colors are applied in the neighboring first grooves in the phosphor layer forming step. For example, the phosphor pastes  301  are applied, for example, in the order of the red phosphor paste, the green phosphor paste and the blue phosphor paste. 
   Accordingly, by conducting discharge in a predetermined display cell in the discharge space of the PDP  100 , the display cell can emit light of a color corresponding to the cell. 
   Other Embodiments 
   It should be noted that the present invention is not limited to the embodiments described above but includes modifications, improvements and the like within a scope where an object of the present invention can be achieved. 
   For instance, although the curb-shaped partition is formed on the rear substrate  120  by the mutually-perpendicular first and second partitions  124 ,  125  in the above embodiment, the arrangement is not limited thereto. For example, the partition layer  123  may be provided in a striped shape by substantially parallel-aligning the plurality of first partition  124 . In this case, as in the above embodiment, the column variation and the luminance variation of the PDP  100  can be prevented by moving the nozzle  200  in a direction substantially perpendicular to the first partition  124  to apply the base-forming agent  201  in the base layer forming step. 
   The applying direction of the base-forming agent  201  is not limited to the direction substantially perpendicular to the first partition  124 . For example, by parallel-moving the applying direction of the plural nozzles  200  in a direction in which the applying direction intersects with the first partitions  124 , the base-forming agent  201  may be applied. 
   EXAMPLES 
   Next, the PDP  100  manufactured by the above-described manufacturing method will be described in detail. 
   Example 1 
   By the manufacturing method of the PDP  100  according to the above embodiment, the base layer  126  was formed, and the phosphor layer  127  was formed on the surface of the base layer  126 . As the base-forming agent for forming the base layer  126 , titania (TiO 2 ) was used. The summed thickness of the base layer  126  and the phosphor  127  was 25 μm while the thicknesses of the base layer  126  and the phosphor layer  127  were respectively 12.5 μm. 
   Comparative Example 1 
   In the manufacturing method of the PDP  100 , the phosphor layer forming step was performed after the partition forming step without performing the base layer forming step. In the phosphor layer forming step, the phosphor pastes was applied in two reciprocations in the same first groove, such that the phosphor layer of 25 μm thickness was formed. 
   Comparative Example 2 
   In the base layer forming step in the manufacturing method of the PDP  100 , the base-forming agent was applied along the second groove by printing to form the base layer. As the base-forming agent for forming the base layer  126 , titania (TiO 2 ) was used. The summed thickness of the base layer  126  and the phosphor  127  was 25 μm while the thicknesses of the base layer  126  and the phosphor layer  127  were respectively 12.5 μm. 
   Comparative Example 3 
   In the base layer forming step in the manufacturing method of the PDP  100 , the nozzle  200  was moved along the first groove to apply the base-forming agent  201 , thereby forming the base layer  126 . As the base-forming agent for forming the base layer  126 , titania (TiO 2 ) was used. The summed thickness of the base layer  126  and the phosphor  127  was 25 μm while the thicknesses of the base layer  126  and the phosphor layer  127  were respectively 12.5 μm. 
   [Evaluation Method] 
   Respective values of in-plane variations  3 σ of the PDP  100  manufactured in Example 1 described above and the PDPs 100 manufactured in Comparative Examples 1 to 3 were measured. The measurement results are shown in Table 1. 
   
     
       
         
             
             
           
             
                 
               TABLE 1 
             
           
          
             
                 
                 
             
             
                 
               Thickness 
             
          
         
         
             
             
             
             
             
             
          
             
                 
                 
                 
                 
               Base 
               In-Plane 
             
             
                 
                 
               Average 
               Phosphor Layer 
               Layer 
               Average 
             
             
                 
               Applying 
               Thickness 
               Thickness 
               Thickness 
               Variation 3σ 
             
             
                 
               Method 
               (μm) 
               (μm) 
               (μm) 
               (μm) 
             
             
                 
                 
             
          
         
         
             
             
             
             
             
             
          
             
               Example 1 
               Perpendicularly 
               25 
               12.5 
               12.5 
               2.3 
             
             
                 
               Applying 
             
             
                 
               Phosphor and 
             
             
                 
               Base-Forming 
             
             
                 
               Agent (Nozzle) 
             
             
               Comparative 
               Phosphor 
               25 
               25 
               25 
               3.9 
             
             
               Example 1 
             
             
               Comparative 
               Print-Applying 
               25 
               12.5 
               12.5 
               2.8 
             
             
               Example 2 
               Phosphor and 
             
             
                 
               Base-Forming 
             
             
                 
               Agent 
             
             
               Comparative 
               Applying 
               25 
               12.5 
               12.5 
               3.6 
             
             
               Example 3 
               Phosphor and 
             
             
                 
               Base-Forming 
             
             
                 
               Agent in the 
             
             
                 
               Same Direction 
             
             
                 
               (Nozzle) 
             
             
                 
             
          
         
       
     
   
   As shown in Table 1, in Comparative Examples 1 and 3, the in-plane average variations  3 σ of the thicknesses of the base layer  126  and the phosphor layer  127  were respectively 3.9 μm and 3.6 μm, whereby a column variation and a luminance variation were observed. In Comparative Example 2, the in-plane average variation  3 σ of the thicknesses of the base layer  126  and the phosphor layer  127  was 2.8 μm, whereby a luminance variation was observed although no column variation was observed. In contrast, in Example 1 described above, the in-plane average variation of the phosphor layer  127  and the base layer  126  was 2.3 μm, whereby neither a column variation nor a luminance variation was observed, and good images were realized. 
   Effects and Advantages of Embodiments 
   As described above, in the manufacturing method of the PDP  100  according to the present embodiment, the first partition  124  and the second partition  125  substantially perpendicular to the first partition  124  are formed on the address-electrode dielectric layer  122  of the rear substrate  120  in the partition forming step, such that the recessed portion  123 A corresponding to the display cell is formed. After the partition forming step, the nozzle  200  is moved along the second groove formed between the second partitions  125  to form the base layer  126  by applying the base-forming agent  201  in the base layer forming step. After the base layer forming step, the phosphor applying nozzle  310  is moved along the first groove formed between the first partitions  124  to form the phosphor layer  127  by applying the phosphor agent  301  in the phosphor layer forming step. 
   With this arrangement, since the base-forming agent is applied with the nozzle  200  in a direction substantially perpendicular to the applying direction of the phosphor paste  301 , the difference in the summed thickness of the base layer  126  and the phosphor layer  127  between the neighboring first grooves can be reduced. In addition, since the variation in the applying direction can be reduced due to the nozzle, the in-plane variation of the summed thickness of the base layer  126  and the phosphor layer  127  can be further reduced. Accordingly, the column variation and the luminance variation between the phosphor layers  127  of the neighboring first grooves can be favorably prevented. In addition, by applying the base-forming agent  201  along the second groove using the nozzle  200 , the base layer  126  can be easily formed. 
   The priority application Number JP2006-341605 upon which this patent application is based is hereby incorporated by reference.