JP5573017B2 - Vacuum ultraviolet excitation phosphor and vacuum ultraviolet excitation light emitting device using the same - Google Patents

Description

  The present invention relates to a vacuum ultraviolet excitation phosphor and a vacuum ultraviolet excitation light emitting device using the same, and more particularly, a vacuum ultraviolet excitation phosphor having a good paste baking luminance maintenance rate and a luminance maintenance rate by gas discharge and a vacuum using the same. The present invention relates to an ultraviolet-excited light emitting device.

  Vacuum ultraviolet-excited phosphors such as alkaline earth aluminate phosphors are plasma displays (hereinafter referred to as PDP), light-emitting devices such as rare gas discharge lamps (vacuum ultraviolet-excited light-emitting devices), and fluorescent lamps containing 185 nm mercury resonance lines. It is used for etc. As shown in FIG. 1 and FIG. 2, the PDP is formed by dividing a sealed gas space sandwiched between two glass plates by partition walls and arranging minute discharge spaces called display cells (discharge cells) in a matrix. Each display cell is coated with a phosphor that emits red, blue, and green light, and is excited by vacuum ultraviolet rays generated by discharge to emit light.

Compared with various flat displays, PDP is being developed widely as the most promising candidate for high-definition wall-mounted TVs because of its features such as the largest size, high-speed response, wide viewing angle, and color reproducibility. . The phosphor used in this PDP has high efficiency and short afterglow with respect to excitation of vacuum ultraviolet rays (VUV) having a wavelength of 200 nm or less obtained by discharge of a rare gas, and sufficient color as three primary colors. In addition to having a degree and a hue, characteristics such as life characteristics and temperature characteristics are required. In particular, alkaline earth aluminate phosphors such as BaMgAl ₁₀ O ₁₇ : Eu, BaMgAl ₁₀ O ₁₇ : Eu, Mn and the like are greatly deteriorated with respect to vacuum ultraviolet rays and ion bombardment, and have problems in life characteristics.

  In addition, the PDP has a phosphor layer in the vicinity of the discharge space, and after preparing a coating composition in which the phosphor and an organic binder are mixed, it is applied to a predetermined site by a slurry method, a printing method, and the like, and then dried. It is formed by baking at a temperature of 400 ° C. to 600 ° C. in the air in order to volatilize the organic binder. However, the alkaline earth aluminate phosphor has a problem that the emission luminance is greatly reduced in this baking step. was there.

  JP-A-2000-303065 discloses a phosphor used in a light-emitting device such as a PDP, but it is disclosed that phosphoric acid or borate is coated. The luminance maintenance rate due to discharge was not sufficient, and improvement was necessary.

JP 2000-303065 A

  In addition to the problems described above, when forming a phosphor layer in a PDP, if the viscosity of the coating composition in which the phosphor and the organic binder are mixed is high, the coating characteristics are poor, and the thin and dense structure corresponding to a fine discharge cell structure is required. There was a problem that it was difficult to form a phosphor screen. Further, since the phosphors of each emission color of red, blue, and green used in the PDP have different discharge start voltages, it is necessary to adjust the discharge start voltage of each phosphor.

  The present invention has been made to solve the above-described problems. An object of the present invention is to provide a vacuum ultraviolet-excited phosphor having good emission luminance, paste baking luminance maintenance rate and luminance maintenance rate by gas discharge, and a vacuum ultraviolet excitation light-emitting device using the same. The object is to provide a vacuum ultraviolet excitation phosphor having good characteristics and capable of adjusting a discharge start voltage, and a vacuum ultraviolet excitation light emitting device using the same.

  As a result of intensive studies to solve the above-mentioned problems, the present inventor has found that the above problems can be solved by a vacuum ultraviolet excitation phosphor coated with tungstic acid or tungstate, thereby completing the present invention. It came to.

(1) The vacuum ultraviolet excitation phosphor of the present invention has tungstic acid or tungstate on the particle surface of the alkaline earth aluminate phosphor activated by at least one activator of Eu and Mn. It is characterized by being coated.

(2) The vacuum ultraviolet excitation phosphor according to the present invention is the vacuum ultraviolet excitation phosphor according to (1), wherein the tungstate is a rare earth tungstate or an alkaline earth tungstate. And

(3) The vacuum ultraviolet-excited phosphor according to the present invention is the vacuum ultraviolet-excited phosphor according to (1) or (2), wherein the coating amount of the tungstic acid is converted to the amount of W element with respect to the phosphor. The coating amount of the tungstate is 0.05 to 8 mol% in terms of the amount of W element with respect to the phosphor.

(4) A vacuum ultraviolet excitation light-emitting device of the present invention comprises the vacuum ultraviolet excitation phosphor described in (1) to (3).

(5) The plasma display device of the present invention includes a front substrate and a rear substrate that are spaced apart from each other by a predetermined distance, a plurality of barrier ribs that form a discharge space by the front substrate and the rear substrate, and a space between the barrier ribs. And a plurality of display electrodes facing and intersecting with the address electrodes, a plurality of discharge cells formed at intersections of the address electrodes and the display electrodes, and at least a part of the inner surface of the discharge cell A plasma display panel comprising: a phosphor layer formed on the substrate; a plasma display panel including a discharge gas sealed in a discharge space between the front substrate and the rear substrate; and a drive circuit for driving the plasma display panel. In the apparatus, the phosphor layer is a phosphor layer having the vacuum ultraviolet excitation phosphor described in (1) to (3).

  The phosphor of the present invention is a vacuum ultraviolet-excited phosphor that has good emission luminance, paste baking luminance maintenance rate and luminance maintenance rate due to gas discharge, good coating characteristics, and can adjust the discharge start voltage. By using the phosphor of the present invention, it is possible to provide a vacuum ultraviolet-excited light emitting device having excellent light emission characteristics, life characteristics and coating characteristics.

It is a schematic diagram of PDP. It is sectional drawing of PDP. It is a figure which shows the relationship between the paste baking brightness maintenance factor (%) of the fluorescent substance of this invention, and the coating amount (equivalent to W) (mol%) of tungstic acid. It is a figure which shows the relationship between the brightness | luminance maintenance factor (%) by the gas discharge of the fluorescent substance of this invention, and the coating amount (W conversion) (mol%) of tungstic acid. It is a figure which shows the relationship between the paste viscosity (Pa * s) of the fluorescent substance of this invention, and the coating amount (W conversion) (mol%) of tungstic acid. It is a figure which shows the relationship between the charging amount (micro | micron | muC / g) of the fluorescent substance of this invention, and the coating amount (equivalent to W) (mol%) of tungstic acid. It is a figure which shows the relationship between the paste baking brightness | luminance maintenance factor (%) of the fluorescent substance of this invention, and the coating amount (W conversion) (mol%) of barium tungstate. It is a figure which shows the relationship between the brightness | luminance maintenance factor (%) by gas discharge of the fluorescent substance of this invention, and the coating amount (W conversion) (mol%) of barium tungstate.

  Hereinafter, a vacuum ultraviolet excitation phosphor according to the present invention and a vacuum ultraviolet excitation light emitting device using the same will be described with reference to embodiments and examples. However, the present invention is not limited to these embodiments and examples.

  Here, the manufacturing method of the vacuum ultraviolet excitation fluorescent substance which concerns on one embodiment of this invention is demonstrated in detail. First, an alkaline earth aluminate phosphor is produced according to a normal method. Next, the phosphor is dispersed in a dispersion medium such as pure water or an aqueous ethanol solution to obtain a phosphor suspension. After adjusting this phosphor suspension to pH 1-7 with an acid, an aqueous solution of a water-soluble tungstate is added to precipitate tungstic acid on the phosphor surface. Alternatively, an aqueous solution of a water-soluble tungstate and an aqueous solution of a water-soluble compound of a rare earth element or alkaline earth element are added to the phosphor suspension, and the rare earth tungstate or alkaline earth tungstate is added to the phosphor. Precipitate on the surface. Thereafter, the treated phosphor and the dispersion medium are separated and dried to obtain the phosphor of the present invention coated with tungstic acid, rare earth tungstate or alkaline earth tungstate.

As the phosphor to be surface-treated, an alkaline earth aluminate phosphor that emits light by excitation with vacuum ultraviolet rays can be used. For example, a divalent europium activated alkali represented by the general formula (Ba, M) ₂ Al ₁₀ O ₁₇ : Eu (where M is at least one element selected from the group consisting of Sr, Ca, and Mg) Earth aluminate phosphor, represented by the general formula (Ba, M) ₂ Al ₁₀ O ₁₇ : Eu, Mn (where M is at least one element selected from the group consisting of Sr, Ca, and Mg) And divalent europium and divalent manganese co-activated alkaline earth aluminate phosphors.

  As the water-soluble tungstate, ammonium tungstate, sodium tungstate, potassium tungstate and the like can be used. As the water-soluble compound of the rare earth element, a water-soluble compound of at least one kind of rare earth element selected from the group consisting of Eu, La, Y and Gd is preferable. Halides, sulfates, nitrates, etc. of these rare earth elements are preferable. Can be used. For example, europium chloride, europium sulfate, europium nitrate and the like can be preferably used. As the alkaline earth element water-soluble compound, a water-soluble compound of at least one alkaline earth element selected from the group consisting of Mg, Ca, Sr, and Ba is preferred, and halides of these alkaline earth elements, Sulfates and nitrates can be used. For example, barium chloride, barium sulfate, barium nitrate, calcium nitrate, strontium nitrate and the like can be preferably used. Moreover, hydrochloric acid, a sulfuric acid, nitric acid etc. can be used as an acid used for pH adjustment.

  When precipitating tungstic acid on the phosphor surface, it is preferable to adjust the pH within the range of pH 1 to 7 on the acidic side, more preferably within the range of pH 1 to 5, and even more preferably within the range of pH 1 to 3. Even if the pH is lower than 1 or higher than 7, the precipitation amount of tungstic acid is reduced and the surface treatment effect is reduced.

  When depositing rare earth tungstate or alkaline earth tungstate on the phosphor surface, an aqueous solution of a water-soluble tungstate and an aqueous solution of a water-soluble compound of a rare earth element or alkaline earth element are added and reacted. Rare earth tungstate or alkaline earth tungstate is deposited.

On the phosphor surface, tungstic acid (H ₂ WO ₄ ), rare earth tungstate europium tungstate (Eu ₂ (WO ₄ ) ₃ ), lanthanum tungstate (La ₂ (WO ₄ ) ₃ ), yttrium tungstate (Y ₂ (WO ₄ ) ₃ ), gadolinium tungstate (Gd ₂ (WO ₄ ) ₃ ), magnesium earth tungstate (MgWO ₄ ), calcium tungstate (CaWO ₄ ), strontium tungstate (SrWO _4). ), Barium tungstate (BaWO ₄ ) is precipitated.

  The coating amount of tungstic acid is preferably in the range of 0.05 to 0.8 mol%, more preferably in the range of 0.1 to 0.6 mol% in terms of the amount of W element with respect to the phosphor. Even if the coating amount is less than 0.05 mol% or more than 0.8 mol%, the paste baking luminance maintenance rate and the luminance maintenance rate due to gas discharge are lowered.

  The coating amount of tungstate is preferably in the range of 0.05 to 8 mol%, more preferably in the range of 0.1 to 6 mol% in terms of the amount of W element with respect to the phosphor. Even if the coating amount is less than 0.05 mol% or more than 8 mol%, the paste baking luminance maintenance rate and the luminance maintenance rate due to gas discharge are lowered.

  Thus, by coating the surface of the alkaline earth aluminate phosphor particles with tungstic acid or tungstate, the vacuum ultraviolet ray has good emission luminance, paste baking luminance maintenance rate, and luminance maintenance rate by gas discharge. An excitation phosphor can be obtained.

  The average particle diameter of the phosphor of the present invention is preferably in the range of 1.0 to 4.0 μm, more preferably in the range of 1.0 to 3.0 μm. Even if the average particle size is smaller than 1.0 μm, or conversely, larger than 4.0 μm, the emission characteristics are deteriorated when used in a vacuum ultraviolet ray excited light emitting device. When the average particle size is smaller than 1.0 μm, the luminous efficiency of the phosphor is low, and when it is larger than 4.0 μm, the surface area of the phosphor particles becomes small and the luminance of light emitted by vacuum ultraviolet excitation is lowered. The vacuum ultraviolet rays reach from the particle surface shallowly, and are excited at the particle surface to emit light. Therefore, when the average particle size is larger than 4.0 μm and the surface area of the phosphor particles is reduced, the emission luminance is lowered. On the other hand, when the average particle size is larger than 4.0 μm, the coating properties are also deteriorated. The median particle size is preferably in the range of 1.5 to 6.0 μm, and more preferably in the range of 1.5 to 4.0 μm. When the median particle size is larger than 6.0 μm, the coating properties are deteriorated. Here, the average particle size was measured using a Fischer Sub Sheave Sizer (FSSS) by the air permeation method, and the median particle size was measured by the electric resistance method Coulter Multisizer II (manufactured by Coulter). Is a 50% value of the cumulative distribution measured using

  Next, a surface discharge type PDP is fabricated as a vacuum ultraviolet light excitation light emitting device using the vacuum ultraviolet light excitation phosphor of the present invention. First, a striped electrode is formed on the back substrate, a striped electrode is formed in a direction orthogonal to the electrode group, and an insulating film and MgO are formed thereon. Further, the aluminate phosphor of the present invention is formed on the counter substrate. The two substrates are combined with a gap of about 100 μm. In this gap, about 670 hPa of a mixed gas of He and Xe, a mixed gas of Ne and Xe, and the like that radiates vacuum ultraviolet rays by discharge is sealed to obtain a surface discharge type PDP.

  Next, the characteristics of the vacuum ultraviolet excitation phosphor of the present invention will be described with reference to the drawings.

<Relationship between paste baking luminance maintenance ratio and tungstic acid coverage>
FIG. 3 shows the paste baking luminance maintenance rate (%) and the coating amount of tungsten acid (converted to W) (mol%) for the BaMgAl ₁₀ O ₁₇ : Eu phosphor coated with tungstic acid in the same manner as in Example 1. Is a plot of the relationship. Here, the paste baking luminance maintenance ratio (%) is measured as follows. 1) A weight ratio of ethyl cellulose: 2- (2-butoxyethoxy) ethanol: terpineol is mixed at a ratio of 8:14:78 to prepare a vehicle. 2) The phosphor and the vehicle are mixed at a weight ratio of phosphor: vehicle = 1: 2 to prepare a paste. 3) The paste is dried at 170 ° C. for 1 hour and then baked at 500 ° C. for 1 hour. 4) Measure the luminance of the phosphor before and after baking at the time of 146 nm vacuum ultraviolet excitation. And the percentage of the value which divided the measured value after baking by the measured value before baking is calculated | required, and this is made into paste baking brightness | luminance maintenance factor (%). From this figure, the paste baking luminance maintenance ratio is high when the coating amount of Tungstic acid (W conversion) is in the range of 0.05 to 0.8 mol%, and is higher in the range of 0.1 to 0.6 mol%. I understand that.

<Relationship between luminance maintenance rate by gas discharge and tungstic acid coating amount>
FIG. 4 plots the relationship between the luminance maintenance rate (%) by gas discharge and the coating amount of tungsten acid (W conversion) (mol%) for the BaMgAl ₁₀ O ₁₇ : Eu phosphor coated with tungstic acid. Is. Next, a method for measuring the luminance maintenance ratio (%) by gas discharge will be described. 1) In the same manner as described above, a paste in which a phosphor and a vehicle are mixed is baked at 500 ° C. for 1 hour to prepare a phosphor measurement sample. 2) Using a vacuum ultraviolet spectrophotometer, the phosphor measurement sample is excited with vacuum ultraviolet light having a wavelength of 147 nm and the emission luminance is measured. 3) The same sample is set in a glass tube filled with a mixed gas of Ne: Xe = 95%: 5% at a pressure of 100 Pa, and arc discharge is performed with an irradiation power of 350 W and an irradiation time of 1 hour to forcibly degrade the phosphor particle surface. . 4) The sample subjected to forced deterioration is excited with vacuum ultraviolet light having a wavelength of 147 nm, and the emission luminance is measured. Then, the percentage of the value obtained by dividing the measured value obtained in 4) by the measured value obtained in 2) is obtained, and this is used as the luminance maintenance rate (%) by gas discharge. From this figure, the luminance maintenance rate (%) by gas discharge is high when the tungstic acid coating amount (in W conversion) is in the range of 0.05 to 0.8 mol%, and more than 0.1 to 0.6 mol% You can see that it is getting higher.

<Relationship between paste viscosity and tungstic acid coating amount>
FIG. 5 is a plot of the relationship between the paste viscosity (Pa · s) and the coating amount of tungsten acid (W conversion) (mol%) for the BaMgAl ₁₀ O ₁₇ : Eu phosphor coated with tungstic acid. is there. Next, a method for measuring the paste viscosity (Pa · s) will be described. 1) A weight ratio of ethyl cellulose: 2- (2-butoxyethoxy) ethanol: terpineol is mixed at a ratio of 8:14:78 to prepare a vehicle. 2) A paste is prepared by mixing 5 g of the phosphor and 10 g of the vehicle. 3) Using a viscometer (TVE-33H manufactured by Toki Sangyo), measure the paste viscosity at a rotor rotation speed of 12 rpm and a measurement temperature of 25 ° C. From this figure, it can be seen that the paste viscosity of the phosphor not coated with tungstic acid is 24.0 Pa · s, but the paste viscosity decreases as the coating amount of tungstic acid increases.

  There was no difference in the dispersibility of the phosphor of the present invention even when tungstic acid was coated, but the viscosity of the coating composition in which the phosphor and the organic binder were mixed was coated with tungstic acid as shown in the figure. Then, the coating characteristics are improved, and a thin and dense phosphor screen corresponding to a fine discharge cell structure such as PDP can be formed.

<Relationship between charge amount and tungstic acid coating amount>
FIG. 6 is a plot of the relationship between the charge amount (μC / g) and the tungstic acid coating amount (in W conversion) (mol%) for the BaMgAl ₁₀ O ₁₇ : Eu phosphor coated with tungstic acid. is there. The charge amount (μC / g) is measured as follows using a blow-off powder charge amount measuring device manufactured by Toshiba Chemical. 200 mg of the phosphor is placed in a cylindrical container with nets on both ends, a high-pressure gas is blown from one end to separate the phosphors, and the phosphor is blown off (blows off) from the mesh openings to determine the charge amount. From this figure, it can be seen that the charge amount of the phosphor not coated with tungstic acid is 2.4 μC / g. When the charge amount of the phosphor shifts to the minus side, the discharge start voltage increases when used in a PDP, and therefore can be effectively used when adjusting the discharge start voltage of the phosphors of each emission color. The charge amount of the phosphor is preferably 2.1 μC / g or less.

<Relationship between paste baking luminance maintenance rate and tungstate coating amount>
FIG. 7 shows paste baking luminance maintenance rate (%) and barium tungstate coverage (W conversion) (mol%) for BaMgAl ₁₀ O ₁₇ : Eu phosphor coated with barium tungstate by the same method as in Example 4. ) Is plotted. The paste baking luminance maintenance rate (%) is measured in the same manner as described above. From this figure, it can be seen that the paste baking luminance maintenance rate is high when the barium tungstate coverage (in W) is in the range of 0.05 to 8 mol% and higher in the range of 0.1 to 6 mol%. .

<Relationship between luminance maintenance rate by gas discharge and tungstate coverage>
FIG. 8 shows the relationship between the luminance maintenance rate (%) by gas discharge and the amount of barium tungstate coating (W conversion) (mol%) for the BaMgAl ₁₀ O ₁₇ : Eu phosphor coated with barium tungstate. It is a plot. The luminance maintenance rate (%) by gas discharge is measured in the same manner as described above. From this figure, the luminance maintenance rate (%) by gas discharge is high when the barium tungstate coating amount (in W conversion) is in the range of 0.05 to 8 mol% and higher in the range of 0.1 to 6 mol%. I understand that.

When the BaMgAl ₁₀ O ₁₇ : Eu phosphor is coated with barium tungstate as described above, the coating amount (in W conversion) and each characteristic of the phosphor show the relationship shown in FIGS. The same relationship is also exhibited when tungstate or rare earth tungstate is coated.

  Examples of the present invention will be described below, but it goes without saying that the present invention is not limited to specific examples.

[Example 1]
50 g of a phosphor represented by the general formula (Ba _0.9 Eu _0.1 ) MgAl ₁₀ O ₁₇ (hereinafter referred to as “BAM phosphor”) is suspended in 250 ml of pure water. A 3.6 wt% aqueous hydrochloric acid solution is added dropwise to adjust the pH to 2.0. After adding 1.25 ml of an aqueous solution of ammonium tungstate adjusted to 2.0 wt% using 7 ammonium tungstate tetrahydrate (made by Showa Chemical Co., Ltd., powder grade 1, 99% purity), the mixture is stirred for 10 minutes. Thereafter, washing, draining, drying, and sieving are performed sufficiently to obtain a BAM phosphor coated with tungstic acid.

[Example 2]
A BAM phosphor coated with tungstic acid is obtained in the same manner as in Example 2 except that 2.50 ml of 2.0 wt% ammonium tungstate aqueous solution is added.

[Example 3]
A BAM phosphor coated with tungstic acid is obtained in the same manner as in Example 2 except that 12.5 ml of 2.0 wt% ammonium tungstate aqueous solution is added.

[Example 4]
100 g of BAM phosphor is suspended in 500 ml of pure water. After adding 2.52 ml of a 2.97 wt% barium nitrate aqueous solution, 5.0 ml of a 2.0 wt% ammonium tungstate aqueous solution is added with stirring, and further stirred for 10 minutes. Thereafter, washing, draining, drying, and sieving are performed sufficiently to obtain a BAM phosphor coated with barium tungstate.

[Example 5]
A BAM phosphor coated with barium tungstate was prepared in the same manner as in Example 4 except that 12.58 ml of 2.97 wt% aqueous barium nitrate solution and 25.0 ml of 2.0 wt% ammonium tungstate aqueous solution were added. obtain.

[Example 6]
A BAM phosphor coated with barium tungstate was prepared in the same manner as in Example 4 except that 37.73 ml of 2.97 wt% barium nitrate aqueous solution and 75.0 ml of 2.0 wt% ammonium tungstate aqueous solution were added. obtain.

[Example 7]
100 g of BAM phosphor is suspended in 500 ml of pure water. After adding 1.09 ml of 2.0 wt% calcium nitrate aqueous solution, 5.0 ml of 2.0 wt% ammonium tungstate aqueous solution is added while stirring, and further stirred for 10 minutes. Thereafter, washing, draining, drying and sieving are performed sufficiently to obtain a BAM phosphor coated with calcium tungstate.

[Example 8]
A BAM phosphor coated with calcium tungstate was prepared in the same manner as in Example 7 except that 5.45 ml of 2.0 wt% calcium nitrate aqueous solution and 25.0 ml of 2.0 wt% ammonium tungstate aqueous solution were added. obtain.

[Example 9]
100 g of BAM phosphor is suspended in 500 ml of pure water. After adding 4.13 ml of 2.0 wt% europium nitrate aqueous solution, 5.0 ml of 2.0 wt% ammonium tungstate aqueous solution is added while stirring and further stirred for 10 minutes. Thereafter, it is sufficiently washed, drained, dried and sieved to obtain a BAM phosphor coated with europium tungstate.

[Example 10]
A BAM phosphor coated with europium tungstate was prepared in the same manner as in Example 9 except that 20.66 ml of 2.0 wt% europium nitrate aqueous solution and 25.0 ml of 2.0 wt% ammonium tungstate aqueous solution were added. obtain.

[Example 11]
100 g of BAM phosphor is suspended in 500 ml of pure water. After adding 2.43 ml of a 1.96 wt% strontium nitrate aqueous solution, 5.0 ml of a 2.0 wt% ammonium tungstate aqueous solution is added while stirring, and further stirred for 10 minutes. Thereafter, it is sufficiently washed, drained, dried and sieved to obtain a BAM phosphor coated with strontium tungstate.

[Example 12]
A BAM phosphor coated with strontium tungstate was prepared in the same manner as in Example 11 except that 12.16 ml of 1.96 wt% strontium nitrate aqueous solution and 25.0 ml of 2.0 wt% ammonium tungstate aqueous solution were added. obtain.

[Comparative Example 1]
A BAM phosphor that is not coated with a surface treatment substance is prepared.

  For the BAM phosphors obtained in Examples 1 to 12 and Comparative Example 1, the surface treatment substances and their coating amounts (in W conversion) (mol%) are shown in Table 1, and the light emission luminance, paste baking luminance maintenance rate, and luminance due to gas discharge are shown in Table 1. The results of measuring the maintenance ratio are shown in Table 2, and the results of measuring the average particle size, median particle size, paste viscosity and charge amount are shown in Table 3, respectively. From these tables, the phosphors of Examples 1 to 12 of the present invention have substantially the same emission luminance as the phosphor of Comparative Example 1, and the paste baking luminance maintenance rate and gas discharge are higher than those of the phosphor of Comparative Example 1. It can be seen that the luminance maintenance rate by is high. In addition, the phosphors of Examples 1 to 12 of the present invention have an average particle size in the range of 1.0 to 4.0 μm and a median particle size in the range of 1.5 to 6.0 μm. It can be seen that the paste viscosity is lower than that of the phosphor, the coating properties are excellent, and the charge amount is on the minus side of the phosphor of Comparative Example 1 and is 2.1 μC / g or less.

  As described above, the vacuum ultraviolet-excited phosphor of the present invention has good emission luminance, paste baking luminance maintenance rate, and luminance maintenance rate due to gas discharge, good coating characteristics, and adjustment of the discharge start voltage. By using this vacuum ultraviolet-excited phosphor in a light-emitting device such as a PDP, it is possible to provide a vacuum ultraviolet-excited light-emitting device having excellent light emission characteristics, life characteristics, and coating characteristics.

11: Front glass substrate 12: Back glass substrate 13: Display electrode 14: Address electrode 15: Dielectric layer 16: Protective layer 17: Dielectric layer 18: Partition wall 19: Phosphor layer 20: Discharge space

Claims (5)

  Vacuum ultraviolet-excited fluorescence characterized in that tungstic acid or tungstate is coated on the particle surface of alkaline earth aluminate phosphor activated by at least one activator of Eu and Mn. body.   The vacuum ultraviolet-excited phosphor according to claim 1, wherein the tungstate is a rare earth tungstate or an alkaline earth tungstate.   The coating amount of the tungstic acid is in the range of 0.05 to 0.8 mol% in terms of the amount of W element with respect to the phosphor, and the coating amount of the tungstate is converted into the amount of W element with respect to the phosphor. The vacuum ultraviolet-excited phosphor according to claim 1 or 2, wherein the range is 0.05 to 8 mol%.   A vacuum ultraviolet ray excitation light emitting device comprising the vacuum ultraviolet ray excitation phosphor according to any one of claims 1 to 3.   A front substrate and a rear substrate that are spaced apart from each other by a predetermined distance, a plurality of barrier ribs that form a discharge space by the front substrate and the rear substrate, an address electrode formed between the barrier ribs, and the address electrode; A plurality of display electrodes that cross each other, a plurality of discharge cells formed at intersections of the address electrodes and the display electrodes, a phosphor layer formed on at least a part of the inner surface of the discharge cells, and the front substrate And a plasma display panel including a discharge gas sealed in a discharge space between the rear substrate and a driving circuit for driving the plasma display panel, wherein the phosphor layer is claimed in claim A plasma display device comprising a phosphor layer comprising the vacuum ultraviolet ray-excited phosphor according to any one of 1 to 3.

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