JP3219075B2 - Plasma display panel and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel (hereinafter referred to as "PDP") utilizing gas discharge light emission for use in a color television receiver or display for displaying characters or images, and a method of manufacturing the same. is there.

[0002]

2. Description of the Related Art A conventional plasma display panel will be described below with reference to the drawings. FIG. 13 is a cross-sectional view schematically showing an AC type (AC type) plasma display panel.

In FIG. 13, reference numeral 41 denotes a front glass substrate, on which a display electrode 42 is formed. Further, the display electrode 42 includes a dielectric glass layer 43 and a magnesium oxide (MgO) dielectric protection layer 44.
(See, for example, JP-A-5-342991).

Reference numeral 45 denotes a rear glass substrate. On the rear glass substrate 45, address electrodes 46, partition walls 47, and phosphor layers (50 to 52) are provided.
Reference numeral 9 denotes a discharge space for filling a discharge gas. The phosphor layer has red 50, green 51, and blue 52 for color display.
Are arranged in order. Each of the above-mentioned phosphor layers (50 to 52) emits and emits light by ultraviolet rays having a short wavelength (147 nm) generated by discharge.

The following materials are generally used as the phosphors constituting the phosphor layers 50 to 52. “Blue phosphor”: BaMgAl ₁₀ O ₁₇ : Eu “Green phosphor”: Zn ₂ SiO ₄ : Mn or BaAl ₁₂
O _19: Mn "red phosphor": Y ₂ O _3: Eu or (YxGd1-
x) BO ₃ : Eu Each color phosphor can be produced as follows.

A blue phosphor (BaMgAl)_TenO₁₇: Eu)
First, barium carbonate (BaCO _Three), Magnesi carbonate
Um (MgCO_Three), Aluminum oxide (α-Al
_TwoO_Three) Is 1: 1: 1: 10 by atomic ratio of Ba, Mg, Al.
To be mixed. Next, a predetermined amount of acid is added to the mixture.
Europium (Eu)_Two03) is added. And the appropriate amount
Flux (AlF_Two, BaCl_Two) With ball mill
At 1400 ° C. to 1650 ° C. for a predetermined time (eg,
0.5 hours), reducing atmosphere (H_Two, N_TwoBaking in the middle)
Get it.

The red phosphor (Y ₂ O ₃ : Eu) is blended with yttrium hydroxide Y ₂ (OH) ₃ and boric acid (H ₃ BO ₃ ) as raw materials so that the atomic ratio of Y and B is 1: 1. I do. Next, a predetermined amount of europium oxide (Eu) was added to the mixture.
₂ O ₃ ) is added, mixed with a suitable amount of flux using a ball mill, and fired in air at 1200 ° C. to 1450 ° C. for a predetermined time (for example, 1 hour).

The green phosphor (Zn ₂ SiO ₄ : Mn) is obtained by converting zinc oxide (ZnO) and silicon oxide (SiO ₂ ) as raw materials.
It is blended so that the atomic ratio of n and Si is 2: 1. Next, a predetermined amount of manganese oxide (Mn ₂ O ₃ ) was added to the mixture, and the mixture was mixed by a ball mill.
C. for a predetermined time (for example, 0.5 hour).

The phosphor particles produced by the above-mentioned method are crushed and sieved to obtain a phosphor material having a predetermined particle size distribution.

Hereinafter, a conventional method of manufacturing a PDP will be described.

An address electrode made of silver is formed on a rear glass substrate, and a visible light reflecting layer made of dielectric glass and a partition made of glass are formed thereon at a predetermined pitch.

A phosphor layer is formed by disposing a phosphor paste of each color including a red phosphor, a green phosphor, and a blue phosphor in each space sandwiched by these partition walls. The phosphor layer is baked to a degree to remove resin components and the like in the paste (phosphor baking step).

After firing the phosphor, a glass frit for sealing with the front plate is applied around the back plate, and calcined at about 350 ° C. to remove resin components and the like in the glass frit (temporarily sealing glass frit). Baking process).

Thereafter, the front plate on which the display electrode, the dielectric glass layer and the protective layer are sequentially formed, and the rear plate are opposed to each other so that the display electrode and the address electrode are orthogonal to each other with a partition wall therebetween. The surroundings are sealed with a glass for sealing (sealing step).

Thereafter, the inside of the panel is evacuated while being heated to about 350 ° C. (evacuation step), and after completion, a discharge gas is introduced at a predetermined pressure.

[0016]

In the conventional method of manufacturing a plasma display panel, there are several steps that require substrate heating as described above.

However, in these heating steps, there is a problem that the phosphor used is thermally degraded, and particularly in the sealing step, the blue phosphor is greatly degraded. This is BaMgAl ₁₀ O ₁₇ : E used as a blue phosphor.
It is considered that Eu2 + ion, which is an activator in u, is oxidized to Eu3 + ion in the sealing step to cause a decrease in emission intensity and deterioration of emission chromaticity.
At this time, the deterioration in the center part in the horizontal direction of the panel is particularly large,
This also caused the blue emission characteristics after the panel was completed to become non-uniform in the plane.

In view of such problems, the present invention hardly causes thermal degradation of the phosphor even through a sealing step required for a panel manufacturing process, operates with relatively high luminous efficiency, and has a color It is an object of the present invention to provide a plasma display panel having good reproducibility.

[0019]

In order to achieve the above object, a plasma display panel according to the present invention comprises an electrode and a back plate between a front plate and a back plate which are disposed to face each other.
A partition wall and a plurality of color phosphor layers having a vertical relationship with the long side are provided, and there is a plasma display panel in which a gas medium is sealed, and in a sealing step between the front plate and the back plate.
Water in the panel sandwiched between the front plate and the back plate
50 in the long side near the hole the backplate to eliminate vapor
It is characterized by being formed adjacently at an interval of not more than cm . Further, the plasma display panel of the present invention,
The electrodes are located between the front plate and the back plate
Partition walls and multiple colors of fluorescence parallel to the long side of the back plate
And a plasma layer in which a gas medium is enclosed.
There is a spray panel for sealing the front plate and the back plate.
A panel sandwiched between the front plate and the back plate in the attaching process.
The hole for removing the water vapor in the back plate is near the short side of the back plate.
Be formed adjacent to each other at an interval of 50 cm or less
May be characterized.

In the above structure, it is preferable that the holes are formed near each of a pair of long sides of the back plate.

[0021]

In the above construction, the back plate has a hole of 30 cm.
Preferably, they are formed adjacently at the following intervals.

[0023]

[0024]

The chromaticity coordinate y (CI) of the emission color when only the blue cells of the plasma display panel are turned on.
(E color system) is preferably 0.08 or less.

The chromaticity coordinate y (CI) of the emission color when only the blue cells of the plasma display panel are turned on.
(E color system) is preferably 0.07 or less.

Further, the chromaticity coordinate y (C) of the emission color when only the blue cell of the plasma display panel is turned on.
IE color system) is preferably 0.06 or less.

Next, a method for manufacturing a plasma display panel of the present invention is disposed opposite a front plate of the backplate
In between, having a partition perpendicular to the long side of the back plate, a method for manufacturing a plasma display panel further comprising a sealing step of sealing the front plate and the back plate, wherein in the sealing step, glass tube open der provided hole upper formed in the long side near the back plate is, the said front plate back
Water vapor in the panel sandwiched between the face plates is
And following a path taken through the hole . In addition, between the front plate and the rear plate
The rear plate has a partition wall parallel to the long side thereof, and further has a front plate
Plasma display having a sealing step of sealing the substrate and the back plate
A method for manufacturing a play panel, comprising:
And provided above a hole formed near the short side of the back plate.
Glass tube is open, the front plate and the back plate
Water vapor in the panel sandwiched between
It may be characterized in that the path is followed and eliminated through said hole .

In the above structure, a pair of long sides of the back plate
Preferably, holes are formed in the vicinity of each.

Preferably, the holes formed in the back plate are adjacent to each other at an interval of 50 cm or less.

Further, the hole formed in the back plate is 30 cm.
It is preferable that they are adjacent at the following intervals.

Preferably, the sealing step is performed in a vacuum atmosphere.

Furthermore, it is preferable that the sealing step is performed in a dry gas atmosphere.

[0034]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for manufacturing a plasma display panel according to an embodiment of the present invention will be described. FIG. 5 is a sectional view schematically showing an AC surface discharge type plasma display panel according to one embodiment of the present invention. In FIG. 5, only one cell is shown, but red,
A PDP is configured by arranging a large number of cells that emit green and blue light.

This PDP comprises a display electrode 22, a dielectric glass layer 23, and a protective layer (MgO) 2 on a front glass substrate 21.
4 and a back plate on which an address electrode 26, a visible light reflection layer 27, a partition wall 28 and a phosphor layer 29 are disposed on a back glass substrate 25, and formed between the front plate and the back plate. A discharge gas is sealed in a discharge space to be discharged.

As the composition of the phosphor material constituting the phosphor layer, those generally used for the phosphor layer of PDP can be used. Specific examples thereof include “blue phosphor”: BaMgAl ₁₀ O ₁₇ : Eu “green phosphor”: Zn ₂ SiO ₄ : Mn “red phosphor”: (YxGd1-x) BO ₃ : Eu. .

FIGS. 2 and 3 show that the blue phosphor (BaMgAl ₁₀ O ₁₇ : Eu) used was baked in air at a peak temperature of 450 ° C. for 20 minutes, and the water vapor partial pressure of air was changed. The measurement results of the relative luminous intensity and the chromaticity coordinate y at the time of dependency on the partial pressure of water vapor are shown. Relative luminous intensity was calculated by comparing the luminous intensity of the blue phosphor
And The chromaticity coordinate y of the blue phosphor before firing is 0.1.
052.

When the partial pressure of water vapor was around 0 Torr, no thermal degradation of luminescence intensity and no change in chromaticity were observed at all, and the relative luminescence intensity became weaker as the partial pressure of water vapor increased. The chromaticity coordinate y increases as the water vapor partial pressure increases. When the chromaticity coordinate y of the blue phosphor increases, a problem occurs that the color reproduction range of the panel is narrowed.

Conventionally, a blue phosphor (BaMgAl)
_It is considered that the luminescence intensity is deteriorated by heating ₁₀ O ₁₇ : Eu) or the y value is increased because the activator Eu 2+ ions are oxidized by heating to Eu 3+ ions. However, as a result of the measurement of the water vapor partial pressure dependency,
It is considered that the thermal deterioration of the blue phosphor is not caused by Eu2 + ions directly reacting with oxygen in the atmosphere (for example, air), but is caused by water vapor in the atmosphere. That is, it has been found that by reducing the partial pressure of water vapor in the atmosphere, it is possible to prevent thermal deterioration due to heating of the blue phosphor (BaMgAl ₁₀ O ₁₇ : Eu).

By the way, the heating temperature is from 300 ° C. to 600 ° C.
In the range, the thermal degradation of the luminescence intensity increases with an increase in the heating temperature, but the tendency is that the thermal degradation increases with an increase in the partial pressure of water vapor. The change in the chromaticity coordinate y did not depend on the temperature, but depended only on the partial pressure of water vapor.

In consideration of the manufacturing process of the plasma display panel, the sealing step of sealing the front plate and the back plate is narrower than that of the phosphor baking step or the glass frit calcining step. Since the gas is confined in the space, it is greatly affected by the gas containing water vapor released from the protective layer (Mg0) on the front plate, the phosphor layer formed on the back plate, or the sealing glass during heating. Conceivable.

When the amount of water vapor released from the above members was measured, the amount of water released from MgO as the protective film was the largest.

The PD according to the present embodiment for eliminating the influence of the gas containing water vapor released from these members will be described below.
P and its sealing step will be described.

FIG. 1 is a diagram schematically showing the positions of holes in the back plate of the PDP in the present embodiment. At the end of the back plate 1, a hole 2 is provided inside the glass frit 5 for sealing, avoiding the partition wall forming portion 3, and a hole must be provided at least at an end perpendicular to the partition wall. There is. These holes 2 include those that also serve to exhaust the inside of the panel sandwiched between the back plate 1 and the front plate 4, fill the discharge gas into the panel, or fill the getter. The holes provided at the ends in the vertical direction of the partition walls of the back plate 1 are provided so as to avoid the address electrodes provided on the back plate 1. When the panel is completed, the hole is sealed with a glass tube.

FIG. 4 is a diagram schematically showing the configuration of a heating device for sealing. The heating device for sealing comprises a gas introduction valve 6 and a gas discharge valve 7 for adjusting the atmosphere gas or the degree of vacuum in the furnace, and a heating furnace 10 for heating the front plate 8 and the back plate 9. A glass tube 12 having both ends opened is fixed to each hole 11 provided in the back plate 9 using a glass frit 13.

In the sealing step, water vapor adsorbed on the front plate 8 and the back plate 9 at the time of temperature rise is released (particularly, M of the front plate is discharged).
gO). Some of these water vapors are
Is removed to the outside through a hole 11 and a glass tube 12. However, when the number of holes is small as in the conventional panel, the steam in the panel cannot be ventilated sufficiently,
The blue phosphor was greatly deteriorated in the sealing step.

Further, in the conventional panel, since the hole position of the back plate is provided only at the end in the direction parallel to the partition wall,
In particular, the central portion in the lateral direction of the panel is greatly deteriorated, which has caused the blue light emission characteristics after the panel is completed to be non-uniform in the plane.

As in the present embodiment, by providing holes at the ends in the direction perpendicular to the partition walls and increasing the number of holes in the back plate, the water vapor generated during sealing can be efficiently and uniformly dispersed. It was removed to the outside, and it became possible to suppress thermal deterioration of the blue phosphor in the sealing step.

Further, by flowing a dry gas such as dry air into the apparatus or heating while performing vacuum evacuation, the partial pressure of water vapor inside the panel can be further reduced, and the deterioration of the blue phosphor is further reduced. Was suppressed. As the water vapor partial pressure of the drying gas, the lower the water vapor partial pressure, the more the deterioration of the blue phosphor was suppressed as shown in FIGS. 2 and 3, but a remarkable effect appeared at around 15 Torr.

After the panel was completely sealed, a glass tube other than the glass tube for exhausting the inside of the panel and filling the discharge gas was partially inserted with a getter and cut off, and then the discharge gas was filled through the evacuation process. . After filling the discharge gas, the glass tube for filling the discharge gas was sealed to complete the panel.

(Example)

[0052]

[Table 1]

The PDPs of panel numbers 1 to 9 are PDPs according to the examples manufactured based on the above embodiment.
The panels are 42 "in size. Panel numbers 1 are shown in FIGS.
9 and FIG. 9 schematically show the back plate hole positions of panel numbers 4 to 9, respectively. Panel numbers 4 to 9 are obtained by changing the atmosphere in the furnace at the time of sealing. Note that dry air was used as a dry gas.

The PDPs with panel numbers 10 to 12 are PDPs according to the comparative example, and the positions of the back plate holes are schematically shown in FIGS.

In each of the above-mentioned PDPs, the sealing step had a temperature profile in which the peak temperature was maintained for 20 minutes. Also,
The panel configuration was the same except for the holes in the back plate, the phosphor film thickness was 30 μm, and the discharge gas was Ne (95%)-Xe (5
%) Was sealed at 500 Torr.

The emission characteristics evaluated by lighting the panel include the emission intensity of blue (a value obtained by dividing the luminance by the chromaticity coordinate y).
And the chromaticity coordinates y were measured at three points (left, center, and right) on the panel. The blue light emission intensity is shown as a relative light emission intensity with the center of panel number 12 of the comparative example being 100.

In the case where the partition and the long side of the back plate are in a vertical relationship, as a result of the comparison of the light emission characteristics of panel numbers 1 to 3, the blue light emission characteristics are improved as the number of holes near the long side of the back plate is increased. The relative luminous intensity increases and the chromaticity coordinate y decreases), and the surface uniformity is improved. This is presumably because as the number of holes increases, the water vapor released inside the panel at the time of sealing becomes more easily ventilated, the water vapor remaining inside the panel decreases, and the thermal degradation of the blue phosphor is suppressed. This means that the same result was obtained as the number of holes near the long side increased, even when the partition and the long side of the back plate were in a parallel relationship. Similar results were obtained even if holes were formed only near the sides.

From the above results, it can be understood that when the water vapor released inside the panel at the time of sealing is ventilated by the hole formed at the end of the panel, it follows the path partitioned by the partition wall. It can be said that it is desirable that a hole is formed at the end of the back plate in the direction perpendicular to the partition wall.

Panel No. 4 shown in FIG. 9 has excellent blue light emission characteristics and excellent surface uniformity.

If the hole positions are the same, panel number 4
From the evaluation comparisons of Nos. To 9, for the same reason, the blue light emission characteristics were improved as the water vapor partial pressure of the dry air in the sealing furnace was lowered. Also, based on the evaluation results of the panel 6, the luminous characteristics were improved by evacuating the inside of the sealing furnace.

Further, in the conventional examples 10 to 12, since all the hole positions are provided at the end portions of the panel in the direction parallel to the partition walls, the partial pressure of water vapor in the panel at the time of sealing becomes non-uniform, and the blue emission characteristic is reduced. Although it was not uniform in the plane, uniform blue light emission was realized in the panel plane by providing a hole in the panel end perpendicular to the partition wall as in the present embodiment.

In the above embodiment, the surface discharge type PDP is exemplified. However, the present invention can be applied to all PDPs which require a heat step for sealing, such as a facing discharge type PDP.

[0063]

As described above, according to the present invention, it is possible to suppress the deterioration of the light emission characteristics of the phosphor which has been generated in the conventional sealing step.
A plasma display panel with a wide color reproduction range can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a hole position of a back plate of a PDP according to an embodiment of the present invention.

FIG. 2 is a diagram showing a water vapor partial pressure dependency of a change in the relative emission intensity of a blue phosphor during heating.

FIG. 3 is a diagram showing a water vapor partial pressure dependency of a change in chromaticity coordinate y of a blue phosphor during heating.

FIG. 4 is a diagram schematically showing a configuration of a heating device for sealing according to an embodiment of the present invention.

FIG. 5 is a schematic sectional view of an AC surface discharge type plasma display panel according to the present embodiment.

FIG. 6 is a schematic view showing a hole position of a back plate of the PDP according to the embodiment of the present invention.

FIG. 7 is a schematic diagram showing the positions of holes in the back plate of the PDP according to the embodiment of the present invention.

FIG. 8 is a schematic view showing a hole position of a back plate of the PDP according to the embodiment of the present invention.

FIG. 9 is a schematic view showing a hole position of a back plate of the PDP according to the embodiment of the present invention.

FIG. 10 is a schematic view showing a hole position of a back plate of a conventional PDP.

FIG. 11 is a schematic view showing a hole position of a back plate of a conventional PDP.

FIG. 12 is a schematic view showing a hole position of a back plate of a conventional PDP.

FIG. 13 is a schematic sectional view of a conventional AC surface discharge type plasma display panel.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 9 Back plate 2, 11 hole 3 Partition formation part 4, 8 Front plate 5 Glass frit for sealing 6 Gas introduction valve 7 Gas discharge valve 10 Heating furnace 12 Glass tube 13 Glass frit

Continuation of the front page (56) References JP-A-8-329846 (JP, A) JP-A-48-79972 (JP, A) JP-A-9-251839 (JP, A) JP-A-2000-149796 (JP, A) A) Fully open 1986-65655 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01J 11/00-11/04 H01J 17/00-17/49 H01J 9/24- 9/395

Claims (22)

(57) [Claims] An electrode, a partition wall perpendicular to a long side of the back plate, and a phosphor layer of a plurality of colors are disposed between a front plate and a back plate which are disposed to face each other, and a gas medium is sealed. Plasma display panel, the front plate and the front
The front plate and the back plate in a sealing process with the back plate.
A hole for eliminating water vapor in the panel sandwiched between the back plate and the long side of the back plate at an interval of 50 cm or less . (2) Between the front plate and the rear plate arranged opposite
In addition, the electrodes, partition walls and the parallel
And a plurality of color phosphor layers, and a gas medium is sealed therein.
There is a plasma display panel, the front plate and the front
The front plate and the back plate in a sealing step with the back plate.
The hole for eliminating water vapor in the panel sandwiched by
Formed adjacent to the short side of the back plate at intervals of 50 cm or less
Plasma display panel characterized in that
Le. 3. A process according to claim 1 or, characterized in that a pair of the hole near each of the long sides of the back plate is formed
3. The plasma display panel according to any one of 2 . 4. A 3 have claim 1 in which the hole in the back plate, characterized in that it is formed adjacent to the following intervals 30cm
A plasma display panel according to any of the preceding claims. 5. A plasma as set forth in claim 1 blue cell only chromaticity coordinates emission color of when is lit y (CIE color system) is characterized in that 0.08 or less to 4 or Display panel. 6. From claim 1 blue cell only chromaticity coordinates emission color of when is lit y (CIE color system) is characterized in that it is 0.07 or less 4 according to any one Plasma display panel. 7. The plasma according to claims 1 blue cell only chromaticity coordinates emission color of when is lit y (CIE color system) is characterized in that less than or equal to 0.06 to 4 either Display panel. 8. Between a front plate and a rear plate disposed opposite to each other.
A plasma display panel manufacturing method , further comprising a sealing step of sealing the front plate and the back plate , the partition having a partition perpendicular to the long side of the back plate. Ri glass tube open der provided hole upper formed in the long side near the face plate, the rear and the front plate
The water vapor inside the panel sandwiched between the boards is removed by the partition walls
A method of manufacturing a plasma display panel, wherein the path is traced and eliminated through the hole . 9. Between the front plate and the rear plate arranged opposite
In addition, the rear plate has a partition wall parallel to the long side thereof, and further has a front plate
Plasma display having a sealing step of sealing the substrate and the back plate
A method for manufacturing a play panel, comprising:
And provided above a hole formed near the short side of the back plate.
Glass tube is open, the front plate and the back plate
Water vapor in the panel sandwiched between
Characterized by following the path and eliminating through the hole
A method for manufacturing a plasma display panel. 10. Near each of a pair of long sides of a back plate.
10. A hole is formed in the hole.
3. The method for manufacturing a plasma display panel according to item 1. 11. The plasma display production method according to any one of claims 8 10, characterized in that said hole is formed 6 or more places. 12. The method according to claim 8, wherein adjacent holes formed in the back plate have an interval of 50 cm or less .
12. The method for manufacturing a plasma display panel according to any one of claims 11 to 11 . 13. The method according to claim 8, wherein adjacent holes formed in the back plate have an interval of 30 cm or less .
12. The method for manufacturing a plasma display panel according to any one of claims 11 to 11 . 14. The method of manufacturing a plasma display panel according to claim 8, wherein the sealing step is performed in a vacuum atmosphere. 15. The method of manufacturing a plasma display panel according to claim 8 , wherein the sealing step is performed in a dry gas atmosphere. 16. A partial pressure of water vapor of a dry gas is 15 Torr.
The method for manufacturing a plasma display panel according to claim 15, wherein: 17. A partial pressure of water vapor of a dry gas is 10 Torr.
The method for manufacturing a plasma display panel according to claim 15, wherein: 18. The method of manufacturing a plasma display panel according to claim 15 , wherein the partial pressure of water vapor of the drying gas is 5 Torr or less. 19. The method of manufacturing a plasma display panel according to claim 15 , wherein a partial pressure of water vapor of the dry gas is 1 Torr or less. 20. The method for manufacturing a plasma display panel according to claim 15, wherein the dry gas does not contain water vapor. 21. The method according to claim 15, wherein the drying gas contains oxygen. 22. The method according to claim 15 , wherein the dry gas is dry air.