JP2003187707A - Plasma display panel - Google Patents

Abstract

(57) [Problem] To improve the bright room contrast of a PDP by arranging an external light antireflection material in a rib constricted portion and using a non-light emitting region as an external light reflection preventing region. SOLUTION: One substrate on which a partition wall for partitioning a discharge space is formed is opposed to the other substrate, the periphery is sealed, a discharge space is filled with a discharge gas, and light emission when a discharge occurs in the discharge space is generated. In a plasma display panel that performs display by utilizing a narrowed portion serving as a non-light emitting region in a groove between partition walls, an anti-reflection material for external light is provided in the narrowed portion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a PDP (plasma display panel), and more specifically, it does not emit light in a groove between ribs like a PDP having a meander rib structure. The present invention relates to a PDP having a rib structure provided with a narrowed portion serving as a region.

[0002]

2. Description of the Related Art As a typical example of a PDP having a rib structure in which a narrow portion serving as a non-light emitting region is provided in a groove between ribs, there is a PDP having a meandering rib structure as disclosed in Japanese Patent Laid-Open No. 9-50768. Are known. PDP with this structure
Is different from the straight rib structure PDP in that the rib has a meandering shape.

In the PDP having this structure, as compared with the PDP having the straight rib structure, the emission region of the phosphor in the cell, which is the minimum unit of light emission, can be made wider, and high brightness can be obtained. Further, the narrowed portion formed between the ribs prevents chain erroneous discharge (crosstalk) in the extending direction of the ribs.

[0004]

Generally, in a PDP, a material having a high light reflectance is used for a dielectric layer or a rib formed on a substrate on the back side in order to efficiently radiate visible light emitted by a phosphor forward. Used. However, when the light reflectance of such a structure increases, the external light reflection of the panel also increases, and as a result, the bright room contrast decreases. Particularly in a PDP having a meandering rib structure, since the aperture ratio is large, the ratio of the region contributing to the reflection of external light is large, and the decrease in bright room contrast is also large.

As a countermeasure against this, it is conceivable to mount an external light reflection suppressing filter on the entire front surface of the panel. However, when such a filter is mounted on the entire front surface of the panel, visible light itself from the inside of the panel is removed. It will be attenuated by the filter.

Further, in the PDP having a meandering rib structure, the front side substrate and the back side substrate are opposed to each other to seal the periphery,
When the impurity gas in the panel is exhausted, the exhaust conductance in the panel becomes low due to the existence of the narrowed portion of the rib, which is a disadvantageous condition for the degassing / exhausting process, which makes the exhausting process longer and the panel This will cause variations in display characteristics.

The present invention has been made in consideration of such circumstances, and by disposing an external light reflection preventing material in the rib narrowing portion and utilizing the non-light emitting region as an external light reflection preventing region, It is intended to improve the bright room contrast of a PDP.

[0008]

SUMMARY OF THE INVENTION According to the present invention, one substrate on which a partition for partitioning a discharge space is formed is opposed to the other substrate, and the periphery is sealed to fill the discharge space with a discharge gas. A plasma display panel for displaying by utilizing light emission when a discharge occurs in a space, wherein a narrow portion which becomes a non-light emitting region is provided in a groove between partition walls, and an external light reflection preventing material is provided in the narrow portion. It is a plasma display panel.

The present invention has the following effects. That is, the narrowed portion formed in the groove between the partition walls is a non-light emitting region, and this region only reflects external light and does not contribute to visible light emission. Therefore, by providing the external light antireflection material in the narrowed portion, it is possible to reduce the external light reflection while securing the same light emitting region as the conventional one, and improve the bright room contrast of the PDP.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a pair of substrates is a substrate made of glass, quartz, ceramics or the like, and desired constituents such as electrodes, insulating films, dielectric layers, protective films, etc. are provided on these substrates. And a substrate on which is formed.

The partition wall can be formed by a sand blast method, a printing method, a photo etching method or the like which is well known in the art. For example, low melting point glass frit, binder,
It can be formed by applying a glass paste made of a solvent or the like on a substrate, drying it, cutting it by a sand blast method, and baking it. It is also possible to use a photosensitive resin for the binder, and perform baking and exposure after development using a mask, followed by baking.

Ne, Xe or the like can be used as the discharge gas to fill the discharge space in the panel. For example, a discharge gas of Ne: 96% and Xe: 4% can be applied.

In the present invention, the narrowed portion means a narrow non-light emitting region provided in the groove between the partition walls. The narrowed portion may be one in which a narrow portion is provided in a groove between the partition walls by forming a protrusion on the linear partition wall, or a groove between the partition walls may be formed by forming a meandering partition wall. Alternatively, a narrow portion may be provided. A meandering rib structure is desirable in the present invention because the meandering rib structure can form a wider width between the partition walls, which is a light emitting region, than the linear partition wall.

The external light reflection means that the light incident on the panel from the outside is reflected to the outside of the panel. If the external light reflectance is high, the bright room contrast of the panel is lowered.
Therefore, the external light antireflection material can be achieved by forming an external light antireflection material having a light reflectance lower than that of the partition wall material, such as a black material layer, in the non-light emitting region of the panel. The black material may be black as long as it absorbs light, and chrome, a black pigment, or the like can be used.

It is preferable that the external light antireflection material is formed as a spacer, and the spacer is provided between the partition wall and the substrate facing the partition wall to form a gap between the partition wall and the substrate. Thereby, the exhaust conductance when exhausting the impurity gas in the panel can be improved.

The external light antireflection material is composed of a black material layer and a coating layer that covers the black material layer to prevent contact with the dielectric layer. The black material layer and the coating layer are formed on the substrate to be abutted against the partition wall. Alternatively, the dielectric layer may be formed thereon.

Alternatively, the external light antireflection material is composed of a metal electrode and a coating layer that covers the metal electrode to prevent contact with the dielectric layer, and the metal electrode and the coating layer are placed on the substrate which is butted against the partition wall. Alternatively, the dielectric layer may be formed thereon. In this case, it is desirable that the coating layer function as a spacer that forms a gap between the partition wall and the substrate that abuts against it.

The external light antireflection material may be composed of a black partition wall material remaining in at least a part of the narrowed portion,
In this case, it is desirable that a spacer be further provided between the partition wall and the substrate facing the partition wall to form a gap between the partition wall and the substrate. This makes it possible to prevent reflection of external light and improve exhaust conductance at the same time.

The present invention will be described in detail below based on the embodiments shown in the drawings. The present invention is not limited to this, and various modifications are possible. An example of the PDP having a meandering rib structure of the present invention will be described with reference to the drawings. Note that the configuration of the PDP described here is an example, and the present invention is not limited to this, and can be applied to any type of PDP such as AC type and DC type as long as it has a meander rib structure. it can.

FIG. 1 shows a PDP having a meandering rib structure according to the present invention.
FIG. 2 is a perspective view showing a part of FIG. 1, and FIG. 2 is an explanatory view showing the PDP of FIG. 1 in a plan view. This PDP is for color display A
It is a C-type three-electrode surface discharge type PDP.

The PDP 10 comprises a front panel assembly including a front substrate 11, and a rear panel assembly including a rear substrate 21. A glass substrate, a quartz substrate, a ceramic substrate, or the like can be used as the front substrate 11 and the rear substrate 21.

On the inner side surface of the substrate 11 on the front side, a plurality of display electrodes X and Y are formed at equal intervals in the horizontal direction. Each of the display electrodes X and Y has a wide transparent electrode 12 such as ITO or SnO ₂ and, for example, A for reducing the resistance of the electrodes.
It is composed of a narrow bus electrode 13 made of metal, such as g, Au, Al, Cu, Cr, and a laminated body thereof (for example, a laminated structure of Cr / Cu / Cr). Display electrode X,
Y can be formed in a desired number, thickness, width, and interval by using a printing method for Ag and Au and combining film forming methods such as vapor deposition method and sputtering method with etching methods for other cases. .

Above the display electrodes X and Y, the display electrodes X and Y are arranged.
An alternating current (AC) driving dielectric layer 17 is formed so as to cover the. The dielectric layer 17 can be generally formed by applying a low melting point glass paste on the front substrate 11 by a screen printing method and baking the paste.

A protective film 18 is formed on the dielectric layer 17 to protect the dielectric layer 17 from damage caused by collision of ions generated by discharge during display. The protective film 18 is made of, for example, MgO, CaO, SrO, BaO or the like.

A plurality of address electrodes A are formed on the inner surface of the substrate 21 on the back side in a direction intersecting with the display electrodes X and Y in plan view, and a dielectric layer 24 is formed so as to cover the address electrodes A. Has been done. The address electrode A is for generating an address discharge for selecting a light emitting cell at the intersection with the display electrode for scanning, for example, Ag, Au,
Al, Cu, Cr and laminates thereof (eg Cr / C
u / Cr laminated structure) and the like. Similarly to the display electrodes X and Y, the address electrode A also uses a printing method for Ag and Au, and a combination of a film forming method such as a vapor deposition method and a sputtering method and an etching method for the others, so that the desired number and thickness can be obtained. It can be formed in any width, width and spacing. The dielectric layer 24 can be formed using the same material and the same method as the dielectric layer 17.

On the dielectric layer 24 between the address electrodes A,
A plurality of ribs 29 are formed in a serpentine pattern along the address electrodes A. The ribs 29 are sandblasted, printed,
It can be formed by a photo etching method or the like. For example, in the sandblast method, a low melting point glass frit,
The dielectric layer 2 is a glass paste made of a binder, a solvent, etc.
After being coated on 4 and dried, cutting particles are sprayed on the glass paste layer with a cutting mask having a partition pattern opening provided on the glass paste layer to cut the glass paste layer exposed at the opening of the mask, It is formed by further firing. Further, in the photo-etching method, a photosensitive resin is used as a binder, and after exposure and development using a mask,
It is formed by firing.

The grooves between the ribs 29 are continuous in the longitudinal direction, but since the ribs 29 are formed in a meandering shape, the wide groove portion (enlarged portion) and the groove are formed. The narrow portions, that is, the narrowed portions 25 are alternately and periodically formed.

The dielectric layer 24 between the side surfaces of the ribs 29 and between the ribs
On the upper side, there are red (R), green (G) and blue (B) phosphor layers 28.
R, 28G and 28B are formed. Phosphor layer 28
R, 28G and 28B are screen-printed with a phosphor paste containing phosphor powder and a binder in the grooves between the ribs 29.
Alternatively, it can be formed by applying by a method using a dispenser, repeating this for each color, and then baking. The phosphor layers 28R, 28G, 28B are
It is also possible to use a sheet-shaped phosphor layer material (so-called green sheet) containing phosphor powder and a binder and to form it by a photolithography method. In this case, by attaching a sheet of a desired color to the entire display area on the substrate, performing exposure and development, and repeating this for each color, it is possible to form a phosphor layer of each color between the corresponding ribs. it can.

In the PDP 10, the front panel assembly and the rear panel assembly described above are arranged so as to face each other so that the display electrodes X and Y and the address electrodes A intersect with each other, and the periphery is sealed, and ribs 29 are provided. It is produced by filling the enclosed discharge space 30 with a discharge gas. This P
In the DP 10, the discharge space 30 at the intersection of the display electrodes X and Y and the address electrode A becomes one cell region (unit light emitting region) which is the minimum unit of display. 1 pixel is adjacent R,
It is composed of three cells, G and B.

For display, first, a display voltage group on the Y side is used as a scan electrode, and a scan voltage is sequentially applied to each of the display electrodes Y, while a desired address electrode A is applied.
An address voltage is applied to the cells to generate an address discharge between the selected address electrode A and the display electrode Y, thereby selecting a cell to emit light. Since wall charges are formed on the dielectric layer corresponding to the light emitting cells, next, a sustain voltage is alternately applied between the Y-side display electrode group and the X-side display electrode group to generate the wall charge. By causing a discharge (referred to as a sustain discharge or a display discharge) again in the cell in which the charge is accumulated, the cell is caused to emit light. The light emission of this cell is performed by exciting the phosphor with the ultraviolet rays generated by the display discharge to generate visible light of a desired color from the phosphor.

In this PDP 10, the display electrodes X and Y are arranged at equal intervals, and surface discharge is possible in the gap between all the adjacent display electrodes X and Y. Therefore, all the display electrodes X and Y are formed. The space becomes the display line. However, the discharge is generated only between the electrodes (cell region) where the rib interval is wide, and the discharge is not generated between the electrodes of the narrowed portion 25 where the rib interval is narrow. Therefore, in this PDP, R, G, and B arranged in a delta shape in two adjacent lines are used.
One cell is composed of the three cells.

Embodiment 1 FIGS. 3 and 4 are explanatory views showing the structure of the narrowed portion of Embodiment 1 in the PDP having the meandering rib structure.
3 shows a plan view, and FIG. 4 shows a cross section taken along the line AA of FIG. 3, showing the narrowed portion 25 in which the green phosphor layer 28G is formed.

As shown in this drawing, a spacer 31 made of a black material having a reflectance lower than that of the rib material is arranged as an external light antireflection material in all the narrowed portions 25 of the panel. The black material of the spacer 31 may be black as long as it absorbs light, and chrome, a black pigment, or the like is used.

The spacers 31 are formed before the front panel assembly and the back panel assembly are bonded together. That is, the dielectric layer 17 is formed on the front substrate 11.
After forming, the paste 29 is applied to the corresponding portion of the narrowed portion 25 of the rib 29 using a technique such as screen printing, and then dried. Alternatively, a glass plate coated with chrome or a black pigment and dried may be bonded with an adhesive. After that, M to cover the entire dielectric layer 17 including the spacers.
A protective film made of gO is formed.

The spacer 31 may be directly formed on the front substrate 11 before the dielectric layer 17 is formed.
In this case, when the spacer 31 is formed of a black pigment paste layer, it is covered with a coating layer such as SiO _{2 or} a glass plate, and the spacer material and the dielectric layer material are burned when firing the dielectric layer. Prevent chemical reactions from occurring. When a black glass plate is used as the coating layer, the black glass plate itself may be used as the spacer 31. Further, the same material as the bus electrode may be used, and the film formed at the same time as the formation of the bus electrode may be used as the spacer.

The spacer 31 is used for the substrate 11 on the front side.
Alternatively, the ribs 29 may be formed on the tops of the ribs 29 of the substrate 21 on the back side. The forming method is the same as that for the front side substrate. The discharge in this panel is generated between the electrodes in the portion where the rib interval is wide.

As described above, by forming the spacer 31 with a black material having a reflectance lower than that of the rib material, it is possible to reduce only external light reflection while keeping the light emitting region as it is, and as a result, bright room. The contrast can be improved.

Further, the rib 2 having no spacer is provided.
Since a gap D is formed between the top of 9 and the substrate 11 on the front side, the panel assembly on the front side and the panel assembly on the back side are bonded to each other to seal the periphery and exhaust the impurity gas in the panel. At this time, since the gap D functions as a ventilation path, the exhaust conductance can be increased, the exhaust process time can be shortened, and the display characteristics of the panel can be prevented from varying.

Regarding the above-mentioned reduction of external light reflection, as a comparative example, a panel having an external light reflection suppressing filter mounted on the entire front surface of the panel and an external light reflection prevention device such as a black spacer in the rib narrowing portion of the present invention are provided. The difference from the panel provided with the material will be described.

When the external light reflectance of the panel in which the external light antireflection material is not provided in the rib narrowing portion and the panel in which the external light antireflection material is provided are examined, the former external light reflectance is 51.03%. The external light reflectance of the latter was 38.96%. In this way, when the external light reflection preventing material is provided in the rib narrowing portion,
The external light reflectance was reduced by 10% or more as compared with the case where it was not provided. Based on the above data, the case where the external light reflection suppressing filter is mounted on the entire front surface of the panel and the case where the external light reflection preventing material is provided in the rib narrowing portion will be compared.

When an external light reflection suppressing filter is provided on the entire front surface of the panel, the brightness of the panel is E, the external light reflectance of the panel is 51%, and the light transmittance of the external light reflection suppressing filter is T (spectral characteristics are taken into consideration. No), the bright room contrast can be expressed by T × E: T × 0.51 × T × I 2. Here, I corresponds to the intensity of external light incident on the PDP. The brightness of black display due to driving the panel shall be ignored.

On the other hand, when the same panel is used but the external light reflection suppressing filter is not used and the external light reflection preventing material is provided in the rib narrowing portion, the panel brightness is E and the external light reflectance of the panel is At 39%, the bright room contrast can be expressed by E: 0.39 × I 2.

Assuming that the bright room contrasts of both are equal, (T × E) / (0.51 × T ² × I) = E / (0.39
When the formula is modified as × I), T = 0.76, and it can be inferred that the bright room contrasts of both are the same when the light transmittance of the external light reflection suppressing filter is 76%. in this case,
Naturally, the display brightness of the panel provided with the external light reflection suppressing filter is only 76% of that of the panel provided with the external light antireflection material.

In reality, it is conceivable that both the external light reflection suppressing filter and the external light reflection preventing material are used and the light transmittance of the external light reflection suppressing filter is set to a high value. When the light transmittance of the external light reflection suppressing filter is selected so that the bright room contrast is the same, when the external light reflection preventing material is provided, it is 1.3 times (= 51 / The light transmittance can be set to 39), and the display brightness can be improved 1.3 times. From the above, it can be said that disposing the external light reflection preventing material in the rib narrowing portion is an effective means as a countermeasure against external light reflection.

Embodiment 2 FIG. 5 and FIG. 6 are explanatory views showing the structure of the narrowed portion of Embodiment 2. 5 shows a plane state, and FIG. 6 shows BB of FIG.
The cross section is shown, and the narrowed portion 25 in which the green phosphor layer 28G is formed is shown.

In this embodiment, both the bus electrodes of the display electrodes X and Y are used as the external light reflection preventing material. That is,
The bus electrode 13 is formed horizontally along the shape of the rib 29, and the spacer 14 is formed at a position corresponding to the rib narrowing portion 25 of the bus electrode 13. Spacer 14
Is a glass plate or the like which is an insulating material. Alternatively, an insulating black pigment or the like may be printed.

In the rib narrowing portion 25, the bus electrode 13 on the X side is formed.
A gap is provided between the Y-side bus electrode 13 and the Y-side bus electrode 13 to prevent both electrodes from contacting each other. In this way, the rib narrowing portion 25
In this region, the adjacent bus electrodes 13 are brought close to each other to have a function of preventing external light reflection. This eliminates the need to use a black material element, which is advantageous in terms of material selection. The discharge in this panel occurs between the electrodes in the portion where the rib interval is wide.

In this structure, X is formed at the rib narrowing portion 25.
Since the bus electrodes on the Y side and the Y side are close to each other, there is a fear of erroneous discharge. However, since the insulating spacer 14 is present in this portion to prevent the discharge from occurring, the erroneous discharge is suppressed. When the dielectric layer 17 is formed by the CVD method, the spacer 1
It is possible to form an isotropic dielectric layer 17 as shown along the shape of FIG.

Third Embodiment FIG. 7 is an explanatory view showing the structure of a narrowed portion of the third embodiment.
This figure shows a planar state. In this embodiment, the bus electrode of the display electrode X is used as an external light reflection preventing material. That is, the bus electrode 13 is formed horizontally along the shape of the rib 29, and the narrowed portion 25 of the rib 29 is completely covered with the bus electrode 13. The X-side electrode is composed of the transparent electrode 12 and the bus electrode 13, and the Y-side electrode is composed of only the bus electrode 13. The cross-sectional state of the rib narrowing portion 25 is the same as in FIG. The discharge in this panel is X at the rib constriction.
Is generated between the transparent electrode 12 on the side and the bus electrode 13 on the side of the Y.

Embodiment 4 FIG. 8 and FIG. 9 are explanatory views showing the structure of a narrowed portion of Embodiment 4. 8 shows a plan view, and FIG. 9 shows CC of FIG.
The cross section is shown. In the present embodiment, the rib narrowing portion 25
Is formed with a shallow groove depth and has a black rib material 29a.
Remain and are black with low external light reflectance. The spacer 14 is formed at a position corresponding to the rib narrowing portion 25. The spacer 14 uses a transparent glass plate.

In this embodiment, the sandblast method is used to form the ribs. To form ribs by this sandblasting method, a rib material layer (rib solid film) is formed and cutting particles are sprayed through a mask corresponding to the shape of the ribs to cut the rib material layer. The cutting speed differs between the wide part and the narrow part of the groove between the ribs, and therefore the cutting speed becomes slower in the rib narrowing part than in other parts. Utilizing this property, the rib material layer is made into two layers. That is, when forming the rib material layer, a material having a high reflectance is formed as a lower layer, and a material having a low external light reflectance, for example, a black material is formed as an upper layer to form the rib material layer. When the rib material layer is cut by sandblasting in this state, black rib material remains in the rib narrowing portion and the rib narrowing portion 25 becomes black even when the cutting of the wide portion of the groove between the ribs is completed. In this way, by intentionally leaving the black rib material in the rib narrowing portion 25, it is possible to provide a function of preventing external light reflection.

With this structure, the rib narrowing portion 25 becomes narrower than in the other embodiments and the exhaust conductance becomes lower, but it is advantageous because it is not necessary to newly add a manufacturing process.

Although the spacer 14 is formed on the dielectric layer 17 of the front substrate 14, it may be formed below the dielectric layer 17. Further, it may be formed on the crown of the rib 29 of the substrate 21 on the back side. Although a transparent glass plate is used for the spacer 14, a black material such as chrome or a black pigment may be used.

By thus providing the external light reflection preventing material in the rib narrowing portion, it is possible to reduce the external light reflection and improve the bright room contrast of the PDP while securing the same light emitting region as the conventional one. Further, by using this external light antireflection material as a spacer between the substrate on the front side and the rib, the exhaust conductance can be improved.

[0055]

According to the present invention, since the external light reflection preventing material is provided in the narrowed portion which is the non-light emitting area formed in the groove between the partition walls, the external light reflection of the panel can be performed without narrowing the light emitting area. The contrast can be reduced and the bright room contrast can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view partially showing a PDP having a meandering rib structure of the present invention.

FIG. 2 is an explanatory diagram showing the PDP of FIG. 1 in a planar state.

FIG. 3 is an explanatory view showing a structure of a narrowed portion according to the first embodiment of the present invention in a planar state.

FIG. 4 is an explanatory view showing a structure of a narrowed portion according to the first embodiment of the present invention in a sectional state.

FIG. 5 is an explanatory view showing a structure of a narrowed portion according to a second embodiment of the present invention in a planar state.

FIG. 6 is an explanatory view showing a structure of a narrowed portion according to a second embodiment of the present invention in a sectional state.

FIG. 7 is an explanatory diagram showing a structure of a narrowed portion according to a third embodiment of the present invention in a planar state.

FIG. 8 is an explanatory view showing a structure of a narrowed portion according to a fourth embodiment of the present invention in a planar state.

FIG. 9 is an explanatory diagram showing a structure of a narrowed portion according to a fourth embodiment of the present invention in a sectional state.

[Explanation of symbols]

10 PDP 11 Front side substrate 12 Transparent electrode 13 bus electrodes 14 Spacer 17 Dielectric layer 18 Protective film 21 Back side substrate 24 Dielectric layer 25 Stenosis 28R, 28G, 28B phosphor layer 29 ribs 29a Black rib material 30 discharge space 31 Spacer A address electrode D gap G discharge area X, Y display electrode

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Osamu Toyota             4-1, Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa             No. 1 within Fujitsu Limited (72) Inventor Yasunobu Hashimoto             4-1, Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa             No. 1 within Fujitsu Limited F-term (reference) 5C040 FA01 FA04 GA03 GB03 GF03                       GF12 GF14 GF16 GH06 GH07                       JA12 JA15 JA17 LA03 LA06                       MA02 MA20 MA22

Claims (8)

[Claims] 1. Light emission when a discharge is generated in the discharge space by facing one substrate on which a partition for partitioning the discharge space is formed to the other substrate and sealing the periphery to fill the discharge space with discharge gas. A plasma display panel which performs display by utilizing a narrowed portion which is a non-light emitting region in a groove between partition walls, and an external light antireflection material is provided in the narrowed portion. 2. The plasma according to claim 1, wherein the partition wall is a meandering partition wall in which a wide portion serving as a light emitting region and a narrow portion serving as a non-light emitting region are alternately formed in a groove between the partition walls. Display panel. 3. The plasma display panel according to claim 1, wherein the external light antireflection material comprises a black material having a light reflectance lower than that of the partition wall material. 4. The plasma display panel according to claim 1, wherein the external light antireflection material is a spacer provided between the partition wall and the substrate facing the partition wall and forming a gap between the partition wall and the substrate. 5. The external light antireflection material comprises a black material layer and a coating layer that covers the black material layer, the black material layer and the coating layer are formed on the other substrate, and a dielectric layer is formed thereon. The plasma display panel according to claim 1, which is formed. 6. The external light antireflection material comprises a metal electrode and a coating layer for coating the metal electrode, the metal electrode and the coating layer are formed on the other substrate, and a dielectric layer is formed thereon. The plasma display panel according to claim 1, wherein 7. The plasma display panel according to claim 5, wherein the coating layer functions as a spacer that forms a gap between the partition wall and the substrate facing the partition wall. 8. The external light antireflection material is made of a black partition wall material remaining in at least a part of the narrowed portion, and a spacer is provided to form a gap between the partition wall and a substrate facing the partition wall. Item 2. A plasma display panel according to item 1.