JP3202964B2 - Phosphor material, phosphor film and plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high luminance and high picture quality of a plasma display panel by enabling the formation of phosphor layer having excellent luminance and emission intensity. SOLUTION: In the phosphor material expressed by BaMgAly Oz : Eu<2+> the amount of the Eu<2+> ion substitution is set to 8% or less, preferably 1 to 6% in atomic ratio to the Ba element in the mother material BaMgAly Oz . This phosphor material is used as the blue phosphor for forming phosphor layer of the plasma display panel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phosphor layer for a plasma display panel and the like, and more particularly to a phosphor material used for forming the phosphor layer and excited by ultraviolet rays.

[0002]

2. Description of the Related Art Plasma display panels (hereinafter referred to as P
DP) is attracting attention as a display capable of realizing a large screen with a small depth, and is roughly classified into a DC type (DC type) and an AC type (AC type). Molds are the mainstream.

FIG. 4 is a schematic sectional view showing an example of a general AC type PDP. In this figure, reference numeral 41 denotes a front glass substrate (front cover plate) on which a display electrode 42 is formed on the surface of the front glass substrate 41, and a dielectric glass layer 43 and a magnesium oxide (MgO) dielectric A body protection layer 44 is coated. Reference numeral 45 denotes a rear glass substrate (back plate). On the surface of the rear glass substrate 45, address electrodes 46, partition walls 47, and phosphor layers 50 to 52 are provided. In the phosphor layers 50 to 52, phosphor layers of three colors of red 50, green 51, and blue 52 are sequentially arranged for color display. Front glass substrate 41 and rear glass substrate 4
Reference numeral 5 denotes a state in which the electrodes 42 and 46 are disposed so as to face each other and are sealed, and a discharge gas is sealed between the partition walls 47 to form a discharge space 49. In each discharge space 49, ultraviolet rays (wavelength: 147 nm) having a short wavelength are generated by the discharge between the display electrodes 42, and the phosphor layers 50 to 52 are excited to emit light, so that red, green, and blue light are emitted. It has become.

[0004] In such a PDP, the phosphor layer comprises:
An ink or a sheet containing phosphor particles excited and emitted by ultraviolet rays is provided on a panel substrate, and then fired at about 500 ° C. to burn off an organic binder component present in the ink or the sheet. As the phosphor particles of each color, the metal element constituting the base material is partially Eu.
Those having a structure substituted with an activator such as or Mn are often used.

[0005]

By the way, in such a firing process, it is known that the phosphor particles forming the phosphor layer undergo a thermal change, and the luminance and chromaticity of the phosphor layer are deteriorated. . In particular, a blue phosphor containing Eu ²⁺ ions as an activator has remarkable deterioration in luminance and emission chromaticity due to firing. In order to cope with such a problem, some measures have been taken to improve the thermal deterioration of the phosphor. For example, see Optical Technology Contact Vol. 34 No. 1 (1996) p. 23-2
No. 4, BaMgAl ₁₄ O ₂₃ : Eu ²⁺ was conventionally known as an excellent blue phosphor. However, deterioration and chromaticity change during panel operation became a problem, and this point was improved. BaMgAl ₁₀ O ₁₇ : Eu ²⁺ was developed as
It is described that the luminance degradation due to firing during panel production was also improved.

[0006] However, as the demand for higher quality of the display is increasing, in the case of PDPs as well, in order to improve the luminance and image quality, the luminance and chromaticity of the phosphor layer are further suppressed from deteriorating and the emission intensity (luminance) is reduced. Is divided by the y value of chromaticity). The present invention has been made under such a background, and it has been made possible to form a phosphor layer having good luminance and emission intensity, and to realize high luminance and high image quality of a PDP or the like. Aim.

[0007]

In order to achieve the above object, the present invention provides a phosphor material for a PDP in which an element to be substituted in a base material is replaced by Eu ²⁺ ions, and particularly, the composition formula is B
aMgAl ₁₀ O ₁₇ : Eu ²⁺ or BaMgAl ₁₄ O ₂₃ :
In the phosphor represented by Eu ²⁺ , the element to be replaced (B
The replacement amount of Eu ²⁺ ion with respect to a) was set to 8 at% or less (preferably 1 to 6 at%).

[0008] Including a phosphor whose composition formula is represented by BaMgAl ₁₀ O ₁₇ : Eu ²⁺ , blue fluorescence having a structure in which an element to be substituted in a base material is replaced by Eu ²⁺ ions as an activator. Conventionally, a body material in which the replacement amount of Eu ²⁺ ions with respect to the element to be replaced is 10 to 15 at% has been used. However, it is necessary to form a phosphor layer using the phosphor material of the present invention. Thereby, the luminance and the light emission intensity can be improved as compared with the related art. When such a phosphor material is used as a blue phosphor material, PDP
Image quality and brightness can be improved. This is because when a PDP is manufactured, a phosphor material is applied and then fired to burn out the binder to form a phosphor layer. However, since the firing is also performed in the step of sealing the panel, the phosphor is used. The material is subjected to firing more than once, and under such conditions, it is better to set the replacement amount of Eu ²⁺ ions to a range smaller than the conventional one, as described above, to obtain high luminance and high emission intensity. Is obtained.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, an outline of the present invention will be described.
As described above, a phosphor material having a structure in which a metal element constituting a base material is partially replaced with an activator is often used for a phosphor layer of a PDP. For example, BaMgAl
_In a blue phosphor material represented by ₁₀ O ₁₇ : Eu ²⁺ ,
It has a structure in which Ba element constituting BaMgAl ₁₀ O ₁₇ which is a base material is replaced by Eu ²⁺ ions.

Conventionally, in such a type of blue phosphor material, as described above, the replacement amount of Eu ²⁺ ions with respect to the element to be replaced (Ba) is set to about 10 to 15 at%. Is considered as follows. The phosphor layer is basically formed through a process in which particles made of a phosphor material are mixed with a binder, applied, and then baked at about 500 ° C. to burn off the binder.

Here, in the case of a phosphor material such as BaMgAl ₁₀ O ₁₇ : Eu ²⁺ , the higher the substitution amount of Eu ²⁺ ions, the higher the initial luminance of the phosphor material and the higher the heat resistance. Since the decrease in the luminance and emission intensity of the phosphor accompanying firing tends to increase because of the decrease, the luminance and the emission intensity of the phosphor layer after firing take excellent values in consideration of this point. In addition, it is considered that the replacement amount of Eu ²⁺ ions was set in the above range (10 to 15 at%).

When a PDP is actually manufactured, after a phosphor layer is formed, baking is usually performed at a temperature of about 400 ° C. to seal the front panel and the back panel. That is, the phosphor in the phosphor layer is exposed to firing twice. Conventionally, since the firing at the time of sealing is performed at a temperature considerably lower than the firing temperature (about 500 ° C.) at the time of forming the phosphor layer, it is considered that the firing is not so affected. However, the present inventors have found that the second baking has a considerable effect on the emission intensity of the phosphor layer. In the case where the phosphor material is exposed to firing twice, it is better to use a phosphor material in which the replacement amount of Eu ²⁺ ions is set to 8 at% or less, which is lower than that of the conventional phosphor material. It has been found that it is preferable to set the substitution amount of Eu ²⁺ ions in the range of 1 to 6 at% in particular.

Hereinafter, embodiments of the present invention will be described. FIG. 1 is a sectional view schematically showing an AC surface discharge type PDP according to one embodiment of the present invention. Although only one cell is shown in FIG. 1, a PDP is formed by arranging a number of cells that emit red, green, and blue light.

This PDP has address electrodes on a front glass substrate (front cover plate) 11 on which display electrodes 12, a dielectric glass layer 13 and a protective layer 14 are arranged, and on a rear glass substrate (back plate) 15. Electrode 16,
The rear panel on which the visible light reflecting layer 17, the partition wall 18 and the phosphor layer 19 are arranged is bonded together, and a discharge gas is sealed in a discharge space formed between the front panel and the rear panel. And manufactured as shown below.

(Fabrication of Front Panel) In the front panel, a display electrode 12 is formed on a front glass substrate 11, and the display electrode 12 is covered with a lead-based dielectric glass layer 13.
3 is formed by forming a protective layer 14 on the surface. In the present embodiment, the display electrode 12 is a silver electrode, and is formed by a method of applying a silver electrode paste by screen printing and then baking. Further, the dielectric glass layer 13
Is formed by applying and firing a paste containing a lead-based glass material by a screen printing method. The composition of the glass material is, for example, 70% by weight of lead oxide [PbO], 15% by weight of boron oxide [B ₂ O ₃ ], and 15% by weight of silicon oxide [SiO ₂ ]. Next, on the above-mentioned dielectric glass layer 13, C
The protective layer 14 of magnesium oxide (MgO) is formed by a VD method (chemical vapor deposition method).

(Production of Back Panel) Back glass substrate 15
An address electrode 16 is formed by screen printing a paste for a silver electrode and then firing the paste, and a paste containing TiO2 particles and dielectric glass particles is applied thereon by a screen printing method and fired. The visible light reflecting layer 17 is formed by the method described above, and a paste containing the same glass particles is repeatedly applied at a predetermined pitch by using a screen printing method, followed by baking to form the partition wall 18.
Then, in each space sandwiched by the partition walls 18, a red phosphor,
One of the green phosphor and the blue phosphor is disposed together with a binder, and the binder is burned off in air to burn off the binder, thereby forming a phosphor layer 19 in which phosphor particles are bound in a film shape. I do. The method of forming the phosphor layer 19 and the phosphor material used will be described later in detail. In the present embodiment, the thickness of the dielectric glass layer 13 is about 20 μm and the thickness of the protective layer 1 is adjusted to match a 40-inch class high-definition television.
4 has a thickness of about 1.0 μm. The height of the partition wall 18 is 0.1 to 0.15 mm, and the partition wall pitch is 0.15 to 0.15 mm.
0.3 mm, and the thickness of the phosphor layer 19 is 5 to 50 μm.

(Preparation of PDP by Panel Lamination)
Next, the front panel and the rear panel thus manufactured are overlapped so that the display electrodes of the front panel and the address electrodes of the rear panel are orthogonal to each other, and a glass for sealing is inserted. Bake for 20 minutes to seal. And, in order to once remove the gas inside the panel,
The panel is fired while evacuating the inside of the panel to a high vacuum (8 × 10 ⁻⁷ Torr) (for example, at about 350 ° C. for 1 hour). Then, the PDP is filled by discharging gas.
Is produced. The discharge gas used in the present embodiment is a Ne—Xe system, the content of Xe is 5% by volume, and the filling pressure is set in the range of 500 to 800 Torr.

(Method for Forming Phosphor Layer and Phosphor Used) FIG. 2 is a schematic configuration diagram of an ink coating apparatus 20 used when forming the phosphor layer 19. As shown in FIG. 2, in the ink application device 20, the phosphor ink is stored in the server 21, and the pressurizing pump 22 pressurizes the ink and supplies the pressurized ink to the header 23. The header 23 is provided with an ink chamber 23a and a nozzle 24. The ink that has been pressurized and supplied to the ink chamber 23a is
The nozzle 24 is continuously jetted.
The header 23 is configured to be scanned on the back glass substrate 15. The scanning of the header 23 is performed by a header scanning mechanism (not shown) that linearly drives the header 23 in the present embodiment. However, the header 23 may be fixed and the rear glass substrate 15 may be linearly driven. Header 23
Is sprayed from the nozzles 24 to form a continuous ink flow 25 (jet line) while scanning, so that the phosphor ink is evenly distributed between the partitions 18 on the rear glass substrate 15. Is applied.

The phosphor ink used here is prepared by mixing phosphor particles of each color, an organic binder and a solvent so as to have an appropriate viscosity (10 to 1000 centipoise at 25 ° C.). Further, a surfactant, silica or the like may be further added and mixed.

As the red phosphor, for example, YBO_Three:
Eu³⁺Ya (YaGd_1-a) BO_Three: Eu³⁺To mention
it can. YBO_Three: Eu³⁺Is YBO which is a base material_ThreeTo
The constituent Y element is Eu³⁺Is substituted by (Y
_aGd_1-a) BO_Three: Eu³⁺Is the parent material (Y_aGd
_1-a) BO_ThreeIs composed of Eu and Gd elements of Eu³⁺Put in
This is a changed structure.

As the green phosphor, for example, Zn_TwoSi
O_Four: Mn²⁺And BaAl₁₂O₁₉: Mn ²⁺To mention
it can. Zn_TwoSiO_Four: Mn²⁺Is the base material Zn
_TwoSiO_FourIs composed of Mn²⁺Replaced by ions
BaAl₁₂O₁₉: Mn²⁺Is the base material
Some BaAl₁₂O₁₉Is composed of Mn²⁺Replace with
It is the structure which was done. These red and green phosphors are
What is generally used in P
You.

On the other hand, as the blue phosphor, BaMgAl
_The one represented by ₁₀ O ₁₇ : Eu ²⁺ is used. E for Ba element constituting BaMgAl ₁₀ O ₁₇ which is a base material
Although those having a substitution amount of u ²⁺ of about 10 to 15% are already used in PDPs, in the present embodiment, the substitution amount of Eu ²⁺ for Ba element is 8 at%, which is lower than the conventional one.
Use the one set below. These red, green and blue phosphors are used in the form of particles having an average particle diameter of 1 to 7 μm.

It is preferable to use ethyl cellulose or an acrylic resin (0.1 to 10% by weight of the ink) as a binder and terpineol (C ₁₀ H ₁₈ O) as a solvent. In addition, as a binder, P
A polymer such as MMA or polyvinyl alcohol can be used, and an organic solvent such as diethylene glycol methyl ether or water can be used as a solvent.

After the red, blue, and green phosphors are provided in this manner, the back glass substrate 15 is placed in a firing furnace,
Baking at a temperature of about 500 ° C. for 10 to 20 minutes. By this baking, the organic binder contained in the phosphor ink or the paste or the resin of the sheet is burned off, and the phosphor layer 19 formed by binding the phosphor particles into a film is formed.

In this case, the phosphor is arranged by the method of scanning while discharging the phosphor ink from the nozzle.
Alternatively, the phosphor can be provided by a method of applying a phosphor paste by a screen printing method. In addition, a sheet of a photosensitive resin containing the phosphor material of each color is prepared, and the sheet is attached to the surface of the rear glass substrate 15 on the side where the partition walls 18 are arranged, and patterned and developed by photolithography. Phosphors can also be provided by a method of removing unnecessary portions.

(Regarding Method for Producing Phosphor Material) The above-mentioned phosphors of each color can be produced, for example, by the following method. Production method of BaMgAl ₁₀ O ₁₇ : Eu ²⁺ which is a blue phosphor:
Barium carbonate (BaCO ₃ ), magnesium carbonate (MgCO ₃ ), aluminum oxide (α-Al ₂ O)
₃ ) and europium oxide (Eu ₂ O ₃ ) are mixed such that the ratio of the number of moles of Ba and the number of moles of Mg to the number of moles of Al becomes 1: 1: 10. I do. Here, the ratio between the number of moles of Ba and the number of moles of Eu is set based on the replacement amount of Eu ²⁺ ions for the Ba element of the target phosphor. For example, when the replacement amount of Eu ²⁺ ions for the Ba element is set to 8 at%, the ratio between the number of moles of Ba and the number of moles of Eu is 92: 8. Accordingly, the molar ratio of barium carbonate, europium oxide, magnesium carbonate and aluminum oxide to be blended is 92: 4: 10
0: 500. Then, an appropriate amount of flux (AlF ₂ , BaCl ₂ ) is added to the above mixture and mixed with a ball mill. Then, baking is performed at a temperature of 1400 ° C. to 1650 ° C. for a predetermined time (for example, 0.5 hour) under a weak reducing atmosphere (in H ₂ and N ₂ ) to reduce a predetermined amount of Eu ²⁺ ions to be replaced. BaMgAl ₁₀ O ₁₇ : Eu ²⁺ particles are obtained.

Production method of YBO ₃ : Eu ^{3+ as} a red phosphor: Yttrium hydroxide Y ₂ (OH) ₃ , boric acid (H ₃ BO ₃ ) and europium oxide (Eu ₂ O ₃ ) were used as raw materials,
Of the number of moles of Eu and the number of moles of Eu) and the number of moles of B
It is blended so as to be 1: 1. Here, the number of moles of Y and E
The ratio of u to the number of moles is set based on the substitution amount of Eu ³⁺ ions for the Y element of the target phosphor. Then, an appropriate amount of flux is added to the above mixture and mixed with a ball mill. And, in the air, 1200 ° C. to 14
By firing at a temperature of 50 ° C. for a predetermined time (for example, one hour), YBO ₃ having a predetermined Eu ³⁺ ion replacement amount is obtained:
Eu ³⁺ particles are obtained.

Production method of Zn ₂ SiO ₄ : Mn ²⁺ which is a green phosphor: zinc oxide (ZnO), silicon oxide (S
iO ₂ ) and manganese oxide (Mn ₂ O ₃ ), when the ratio of (the sum of the mole number of Zn and the mole number of Mn) and the mole number of Si is:
Mix so as to be 2: 1. Here, the ratio between the number of moles of Zn and the number of moles of Mn is determined based on the substitution amount of Mn ²⁺ for the Zn element of the target phosphor. Next, they are mixed by a ball mill. Then, in air at 1200 ° C ~ 1
By firing at a temperature of 350 ° C. for a predetermined time (for example, 0.5 hour), Zn ₂ S having a predetermined Mn 2+ substitution amount is obtained.
iO ₄ : Mn ²⁺ particles are obtained.

[0029]

EXAMPLE Based on the above embodiment, a PDP of an example will be described.
Was prepared. The green phosphor is Zn ₂ SiO ₄ : Mn ²⁺ (M
n content is 2.3% by weight), and the red phosphor is YB
O ₃ : Eu ³⁺ (the substitution amount of Eu ³⁺ with respect to the Y element is 0.
1) was used. The blue phosphor is BaMgAl ₁₀ O ₁₇ : E
u ²⁺ , and the substitution amount of Eu ²⁺ ions with respect to the Ba element of the base material, As shown in FIGS.
The values set at 5, 2.0, 5.0, and 8.0 at% were used. In Table 1, the composition of the blue _{phosphor, Ba 1-x MgAl 10 O} 17: is expressed as Eu _x. This represents the same phosphor as BaMgAl ₁₀ O ₁₇ : Eu ²⁺ , but the x value indicating the replacement amount of Eu ²⁺ ions with respect to the Ba element of the base material is described in the formula.

[Table 1]

The average particle size of the phosphors of each color was about 3 μm. The baking after forming the phosphor layers was performed at 520 ° C. for 10 minutes, and the baking at the time of panel bonding was performed at 460 ° C. for 10 minutes. The thickness of the phosphor layer was set at 20 μm, and the discharge gas pressure was set at 500 Torr. In addition, panel No. of Table 1 5 is the PD of the comparative example
This is a PDP produced in the same manner as in the example except that the substitution amount of Eu ²⁺ ions for Ba element was set to 10 at% (x = 0.100).

<Experiment 1> The color-temperature-unadjusted luminance and the color-temperature-adjusted luminance of the PDPs of the examples and the comparative examples manufactured as described above were measured. What is color temperature unadjusted brightness?
The luminance when white display is performed by inputting the same signal to the three colors (that is, by generating the same ultraviolet rays in the discharge spaces of the three colors). The color temperature adjustment luminance is obtained by adjusting the signal of each color and adjusting the color temperature. This is the luminance when displaying 9500 degrees of white. The measurement of these luminances was performed at a discharge sustaining voltage of 150 V and a frequency of 30 k.
Hz. The measurement results are shown in Table 1 above.

Looking at the measurement results shown in Table 1, the color temperature non-adjusted luminance is as shown in FIG. 1-4 (x = 0.005-0.0
No. 80). 5 (x = 0.100) shows a higher value.
No. 5 (x = 0.100). 1-4 (x = 0.
005 to 0.080) shows a higher value. This result indicates that the panel luminance can be improved in the PDP by setting the x value of the blue phosphor to 0.08 or less, which is smaller than the conventional value. Especially N
o. 2 (x = 0.020) and No. 2 3 (x = 0.05
The color temperature adjustment luminance of 0) indicates a high value. The measurement of the color temperature adjustment luminance is performed in consideration of the fact that it is necessary to balance white in order to improve the image quality in an actual PDP. The higher the color temperature adjustment luminance, the higher the luminance while maintaining the image quality. can get.

The reason why a high panel luminance can be obtained by setting the x value of the blue phosphor to 0.08 or less as described above is considered to be that the emission intensity of the blue phosphor is increased. Can be That is, in order to obtain good image quality in a PDP, it is required that the color temperature be 9000 ° C. or more in white balance. However, since blue phosphors usually have lower luminance than phosphors of other colors, When all the colors are illuminated by the same signal, the color temperature is about 6000 degrees, and good image quality cannot be obtained. In order to increase the color temperature to 9000 degrees or more, it is necessary to perform signal adjustment to lower the luminance of green and red as compared with blue, but as the emission intensity of the blue phosphor increases, the luminance of green and red increases. Less often,
A high value can be obtained for the color temperature adjustment luminance.

No. In 1 (x = 0.005),
No. The color temperature adjustment luminance is lower than 2 (x = 0.020), which is considered to be because the amount of Eu ²⁺ ions in the blue phosphor is too small and the excitation probability of ultraviolet rays is low.

<Experiment 2> BaMg which is a blue phosphor material
For Al ₁₀ O ₁₇ : Eu ²⁺ , Eu
The relationship between the replacement amount of ²⁺ ions and the heat resistance was investigated. When producing BaMgAl ₁₀ O ₁₇ : Eu ²⁺ by the above-mentioned production method, various x values (replacement amounts of Eu ²⁺ ions) are obtained by changing the addition amount of europium oxide (Eu ₂ O ₃ ).
The Ba _1-x MgAl ₁₀ O ₁₇ having: was prepared Eu _x. Then, a phosphor paste was prepared using each of the prepared phosphor materials, applied to a substrate, and baked in air at 520 ° C. for 10 minutes to form a phosphor layer. Then, the formed phosphor layer is further heated in air at 460 ° C. for 1 hour.
Bake for 0 minutes.

Here, before firing at 520 ° C. (when not yet fired), after firing at 520 ° C. (after firing once), 460 ° C.
After baking (after baking twice), the phosphor layer
The luminance and emission intensity of the phosphor layer were examined while irradiating the lamp with ultraviolet light. The luminance was measured using a luminance meter. The emission intensity was obtained by measuring the emission spectrum from the phosphor layer using a spectrophotometer, calculating the y value of chromaticity from the measured value, and calculating the y value of chromaticity and the measured value of luminance ( Luminance / chromaticity y value).

FIGS. 3A and 3B show the measurement results, wherein FIG. 3A is a characteristic diagram showing the relationship between the x value and the relative luminance, and FIG. 3B is a characteristic diagram showing the x value and the relative emission intensity. In each of the figures, the solid line shows the characteristics after unsintering, the broken line shows the characteristics after one firing, and the dashed line shows the characteristics after two firings. 3 (a) and 3 (b), the values of the relative luminance and the relative light emission intensity are both x =
It is indicated by an index when the value of the phosphor when unfired is set to 100 with 0.1 phosphor.

The following can be seen from the characteristic diagrams of FIGS. 3 (a) and 3 (b). * In the unfired state, the luminance increases as the x value increases, but the luminescence intensity is highest near the x value of 0.1. * After one firing, the luminance was x value of 0.
The light emission intensity is highest at a value slightly larger than 1, and the emission intensity is almost constant when the x value is 0.1 or less, but decreases as the x value increases when the x value exceeds 0.1. ing. From this, when the determination is made based on the measurement result after the first firing, the x value is set to 0.1 to 0.
It is derived that setting to about 15 is suitable for obtaining a high-performance phosphor layer. * After firing twice,
The luminance shows the highest value when the x value is slightly smaller than 0.1, and keeps a high value even when the x value becomes considerably small. The luminous intensity is highest near x = 0.03 to 0.06, and considerably decreases in a range exceeding x = 0.08. From this, it can be seen that the value of x is preferably 0.08 or less, particularly 0.01 to 0.06, and more preferably 0.03 to 0.06 after firing twice.

* Of particular note is that the x value is 0.08
In the larger range and the range of 0.08 or less, the effect of the firing on the emission intensity shows the opposite tendency. That is, in the range where the x value is larger than 0.08, the emission intensity after firing is lower than that in the case where the firing is not performed. On the other hand, when the x value is 0.08 or less, the emission intensity is lower. The luminous intensity after firing is higher than that after firing, and the luminance and luminous intensity after firing twice are higher than after firing once. The difference in the tendency is that Eu ²⁺ ions are oxidized and impurities such as moisture are removed or the crystallinity is improved as the phosphor is baked, which contributes to the improvement of the emission intensity. However, it is considered that the effect of the former is greater in the range where the x value is larger than 0.08, whereas the effect of the latter is greater when the x value is 0.08 or less.

In this experiment, the case of firing at 460 ° C. after firing at 520 ° C. was examined.
In the case of baking at about 350 ° C. after baking at about the same degree, or in the case of performing baking twice at the same temperature (for example, 460 ° C.), almost the same results can be obtained. In FIG. 3, firing at 520 ° C. is followed by firing at 460 ° C.
Although the measurement results up to the second firing are shown, when the third firing is performed at a temperature of 460 ° C. or less and the measurement is performed thereafter, the result shows the same tendency as the result after the second firing. was gotten. That is, it was found that the tendency of the luminance and the light emission intensity after the second firing as shown by the one-dot chain line in FIG.

(Other Matters) In the above embodiment, E
u²⁺Examples of blue phosphors containing ions as activators
And BaMgAl_TenO₁₇: Eu²⁺Indicates the phosphor represented by
However, the present invention is not limited to this.
₁₄O_{twenty three}: Eu²⁺And BaaSr_1-aMgAl_TenO₁₇: Eu ²⁺
It can be applied even when using a blue phosphor such as
is there. That is, BaMgAl₁₄O_{twenty three}: Eu²⁺Then, Ba yuan
Eu for elementary²⁺The amount of ion replacement is represented by Ba_aSr_1-aMg
Al_TenO₁₇: Eu²⁺Now, the sum of Ba element and Sr element
Eu²⁺The ion substitution amount is 8 at% or less (preferably
Is 1 to 6 at%).
Can be obtained. In the above embodiment, AC
Although the explanation has been given taking the example of the PDP of the DC type,
The same can be said about this. In the above embodiment,
The blue phosphor described is not necessarily used only for PDPs
Can be used for fluorescent lamps
You. And, in that case, the same effect can be obtained.

[0042]

As described above, the present invention provides a phosphor material in which an element to be substituted in a base material has been replaced by Eu ²⁺ ions,
Particularly composition formula BaMgAl ₁₀ O _17: in the phosphor represented by Eu ^2+, Eu ²⁺ for elements to be replaced (Ba)
The ion substitution amount is 8 at% or less, preferably 1 to 6 at
By setting to%, a phosphor film having higher heat resistance than before can be formed, and the luminance and the emission intensity of the phosphor layer can be improved. When such a phosphor material is used as a blue phosphor material, thermal degradation of the phosphor layer in the firing process at the time of PDP production is suppressed, and
The image quality and luminance of P can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a configuration of an AC surface discharge type PDP according to an embodiment.

FIG. 2 is a schematic configuration diagram of an ink application device used when forming a phosphor layer in the embodiment.

FIG. 3 is a characteristic diagram showing an experimental result using a phosphor material of an example.

FIG. 4 is a schematic sectional view showing an example of a conventional AC surface discharge type PDP.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Front glass substrate 12 Display electrode 13 Dielectric glass layer 14 Protective layer 15 Back glass substrate 16 Address electrode 17 Visible light reflection layer 18 Partition wall 19 Phosphor layer 20 Ink coating device

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-56-86982 (JP, A) JP-A-11-40066 (JP, A) JP-A-8-508307 (JP, A) US Patent 3294699 (US) , A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C09K 11/00-11/89 H01J 9/22-9/227 H01J 11/02

Claims (4)

(57) [Claims] 1. BaMgAl _Ten O ₁₇ : Eu ²⁺ Represented by
And BaMgAl _Ten O ₁₇ Eu for Ba element ²⁺ Io
Display with a substitution amount of 8 at% or less
Phosphor material for panel. 2. The BaMgAl _Ten O ₁₇ Of the Ba element
Eu ²⁺ The amount of ion substitution is 1 to 6 at%.
2. The phosphor material for a plasma display panel according to 1. 3. BaMgAl ₁₄ O _{twenty three} : Eu ²⁺ Represented by
And BaMgAl ₁₄ O _{twenty three} Eu for Ba element ²⁺ Io
Display with a substitution amount of 8 at% or less
Phosphor material for panel. 4. The BaMgAl ₁₄ O _{twenty three} Of the Ba element
Eu ²⁺ The amount of ion substitution is 1 to 6 at%.
4. The phosphor material for a plasma display panel according to 3.