JP2013062040A - Plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly efficient plasma display panel short in decay time, and high in brightness and color purity.SOLUTION: The plasma display panel comprises a red phosphor layer emitting visible light by vacuum ultraviolet rays. The red phosphor layer contains a phosphor represented by general formula: (1-a-b)YO-aGdO-bEuO-cAlO(0≤a≤0.47, 0.05≤b≤0.15, 0.90≤c≤1.10). In the general formula, it is particularly preferable that 0≤a≤0.37, 0.05≤b≤0.10 and 0.95≤c≤1.05 are satisfied.

Description

  The present invention relates to a plasma display panel (PDP).

In recent years, (Y, Gd) BO ₃ : Eu, which has high luminance by vacuum ultraviolet light excitation, has been widely used for red phosphors for PDP. (Y, Gd) BO ₃ : Eu is less degraded by the panel manufacturing process and exhibits good chromaticity by appropriate optical filter design.
However, when (Y, Gd) BO ₃ : Eu is used, the afterglow time becomes as long as about 10 ms, and the moving image characteristics as a PDP deteriorate. Further, in a PDP (3D-PDP) that can express a stereoscopic video, if the afterglow time becomes long, moving image crosstalk (overlap of the left-eye image and the right-eye image) deteriorates and the stereoscopic video breaks down. Therefore, a red phosphor having a short afterglow time is strongly demanded for PDP applications.
On the other hand, for example, Patent Document 1 discloses a method using (Y, Gd) ₂ O ₃ : Eu. Patent Document 2 discloses a method using (Y, Gd) (P, V) O ₄ : Eu.

JP-A-10-195432 Japanese Patent Laid-Open No. 11-73138

However, although the phosphor disclosed in Patent Document 1 has a shorter afterglow time than a red phosphor using (Y, Gd) BO ₃ : Eu, it cannot obtain red light emission with good color purity.
In addition, the phosphor disclosed in Patent Document 2 has a short afterglow time and improved chromaticity, but has a large deterioration in the panel manufacturing process, so that the luminance of the PDP is lowered.
An object of the present invention is to solve the above-described conventional problems, and to provide a PDP having a short afterglow time, high efficiency, and good color purity.

The PDP of the present invention that has solved the above problems is a plasma display panel including a red phosphor layer that emits visible light by vacuum ultraviolet rays, and the red phosphor layer has the general formula (1-a- b) YO _3/2 · aGdO _3/2 · bEuO _3/2 · cAlO _3/2 (0 ≦ a ≦ 0.47, 0.05 ≦ b ≦ 0.15, 0.90 ≦ c ≦ 1.10) .
In the above general formula, it is particularly preferable that 0 ≦ a ≦ 0.37, 0.05 ≦ b ≦ 0.10, 0.95 ≦ c ≦ 1.05.

  According to the present invention, a PDP having a short afterglow time, high efficiency, and good color purity can be provided.

It is a schematic sectional drawing which shows the structure of PDP of this invention.

  Hereinafter, embodiments of the present invention will be described in detail.

<Composition of phosphor>
The phosphor of the present invention has a general formula (1-ab) YO _3/2 · aGdO _3/2 · bEuO _3/2 · cAlO _3/2 (0 ≦ a ≦ 0.47, 0.05 ≦ b ≦ 0.15, 0.90 ≦ c ≦ 1.10). In the general formula, preferable ranges from the viewpoint of luminance are 0 ≦ a ≦ 0.37, 0.05 ≦ b ≦ 0.10, 0.95 ≦ c ≦ 1.05.

<Method for producing phosphor>
Hereinafter, although the manufacturing method of the fluorescent substance of this invention is demonstrated, the manufacturing method of the fluorescent substance of this invention is not restricted to the following.

  As a raw material, a high purity (purity 99% or more) hydroxide, oxalate, nitrate, or the like, a compound that becomes an oxide by firing, or a high purity (purity 99% or more) oxide can be used.

  In order to accelerate the reaction, it is preferable to add a small amount of fluoride (such as aluminum fluoride) or chloride (such as aluminum chloride).

  The phosphor is produced by mixing and firing the above raw materials. The raw material may be mixed by wet mixing in a solution or dry mixing of a dry powder. A medium stirring mill, a planetary mill, a vibration mill, a jet mill, a V-type mixer, a stirrer, or the like can be used.

  The method for firing the mixed powder varies depending on the composition system of the phosphor. The phosphor of the present invention is baked in the atmosphere at a temperature range of 1100 to 1500 ° C. for about 1 to 50 hours.

  The furnace used for firing may be an industrially used furnace, and a continuous or batch type electric furnace or gas furnace such as a pusher furnace may be used.

  The obtained phosphor powder is pulverized again using a ball mill, a jet mill or the like, and further washed or classified as necessary, thereby adjusting the particle size distribution and fluidity of the phosphor powder.

<Use of phosphor>
Since the phosphor of the present invention has a short afterglow time and high luminance and color purity, if the phosphor of the present invention is applied to a light emitting device having a phosphor layer, a highly efficient light emitting device can be configured. it can. Specifically, conventional (Y, Gd) _BO 3: the red phosphor such as Eu: the light-emitting device having a phosphor layer red phosphor is used, such as _{Eu, (Y, Gd) BO} 3 The phosphor of the invention may be substituted and a light emitting device may be constructed according to a known method. Examples of the light emitting device include a PDP, a fluorescent panel, a fluorescent lamp (eg, a mercury-free fluorescent lamp), and among these, a PDP is preferable.

  Hereinafter, the PDP of the present invention will be described by taking an AC surface discharge type PDP as an example. FIG. 1 is a perspective sectional view showing the main structure of an AC surface discharge type PDP 10. For convenience, the PDP shown here is illustrated with a size setting in accordance with the 1024 × 768 pixel specification of the 42-inch class, but may be applied to other sizes and specifications. .

  As shown in FIG. 1, the PDP 10 includes a front panel 20 and a back panel 26 and is disposed so that the main surfaces thereof face each other.

  The front panel 20 includes a front panel glass 21 as a front substrate, strip-shaped display electrodes (X electrodes 23 and Y electrodes 22) provided on one main surface of the front panel glass 21, and a thickness covering the display electrodes. The front-side dielectric layer 24 having a thickness of about 30 μm and a protective layer 25 having a thickness of about 1.0 μm provided on the front-side dielectric layer 24 are included.

  The display electrode includes a strip-shaped transparent electrode 220 (230) having a thickness of 0.1 μm and a width of 150 μm, and a bus line 221 (231) having a thickness of 7 μm and a width of 95 μm provided on the transparent electrode. Yes. A plurality of pairs of display electrodes are arranged in the y-axis direction with the x-axis direction as the longitudinal direction.

  Each pair of display electrodes (X electrode 23, Y electrode 22) is electrically connected to a panel drive circuit (not shown) in the vicinity of the end of the front panel glass 21 in the width direction (y-axis direction). Has been. The Y electrodes 22 are collectively connected to the panel drive circuit, and the X electrodes 23 are independently connected to the panel drive circuit. When power is supplied to the Y electrode 22 and the specific X electrode 23 using the panel drive circuit, a surface discharge (sustain discharge) is generated in the gap (about 80 μm) between the X electrode 23 and the Y electrode 22. The X electrode 23 can also be operated as a scan electrode, and thereby, a write discharge (address discharge) can be generated between the X electrode 23 and an address electrode 28 described later.

  The back panel 26 includes a back panel glass 27 as a back substrate, a plurality of address electrodes 28, a back side dielectric layer 29, a partition wall 30, red (R), green (G), and blue (B). Phosphor layers 31 to 33 corresponding to any of them are included. The phosphor layers 31 to 33 are provided in contact with the side walls of two adjacent barrier ribs 30 and the back-side dielectric layer 29 therebetween, and are repeatedly arranged in the x-axis direction.

The red phosphor layer (R) includes the above-described red phosphor of the present invention. On the other hand, the green phosphor layer (G) and the blue phosphor layer (B) contain a general phosphor. For example, the green phosphor includes Zn ₂ SiO ₄ : Mn, a mixture of Zn ₂ SiO ₄ : Mn and Y ₃ Al ₅ O ₁₂ : Ce, and the blue phosphor includes BaMgAl ₁₀ O ₁₇ : Eu.

  For each phosphor layer, a phosphor ink in which phosphor particles are dissolved is applied to the partition wall 30 and the back side dielectric layer 29 by a known coating method such as a meniscus method or a line jet method, and this is dried or baked. (For example, 10 minutes at 500 ° C.). The phosphor ink comprises, for example, 30% by mass of a green phosphor having a volume average particle diameter of 2 μm, 4.5% by mass of ethyl cellulose having a weight average molecular weight of about 200,000, and 65.5% by mass of butyl carbitol acetate. Can be produced. Further, it is preferable to adjust the viscosity so that the viscosity finally becomes about 2000 to 6000 cps (2 to 6 Pas), because the adhesion force of the ink to the partition wall 30 can be increased.

  The address electrode 28 is provided on one main surface of the back panel glass 27. The back side dielectric layer 29 is provided so as to cover the address electrodes 28. The partition wall 30 has a height of about 150 μm and a width of about 40 μm, and is provided on the back-side dielectric layer 29 in accordance with the pitch of the adjacent address electrodes 28 with the y-axis direction as the longitudinal direction. Yes.

  Each of the address electrodes 28 has a thickness of 5 μm and a width of 60 μm, and a plurality of address electrodes 28 are arranged in the x-axis direction with the y-axis direction as the longitudinal direction. The address electrodes 28 are arranged so that the pitch is a constant interval (about 150 μm). The plurality of address electrodes 28 are independently connected to the panel drive circuit. By supplying power individually to each address electrode, it is possible to cause an address discharge between the specific address electrode 28 and the specific X electrode 23.

  The front panel 20 and the back panel 26 are arranged so that the address electrodes 28 and the display electrodes are orthogonal to each other. The outer peripheral edge portions of both panels 20 and 26 are sealed by a frit glass sealing portion (not shown) as a sealing member.

In a sealed space between the front panel 20 and the back panel 26 sealed by the frit glass sealing portion, a discharge gas composed of a rare gas component such as He, Xe, Ne or the like has a predetermined pressure (usually 6.7 × 10 ^{4 to} 1.0 × 10 ⁵ Pa).

  A space corresponding to the space between two adjacent barrier ribs 30 is a discharge space 34. A region where a pair of display electrodes and one address electrode 28 intersect with each other across the discharge space 34 corresponds to a cell displaying an image. In this example, the cell pitch in the x-axis direction is set to about 300 μm, and the cell pitch in the y-axis direction is set to about 675 μm.

  When driving the PDP 10, the panel drive circuit applies a pulse voltage to the specific address electrode 28 and the specific X electrode 23 to cause address discharge, and then a pair of display electrodes (X electrode 23, Y electrode 22). A pulse is applied during the period to sustain discharge. The phosphors contained in the phosphor layers 31 to 33 are caused to emit visible light using the short wavelength ultraviolet rays (resonance lines having a central wavelength of about 147 nm and molecular beams having a central wavelength of 172 nm) generated thereby. Thus, a predetermined image can be displayed on the front panel side.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated in detail, this invention is not limited to these Examples.

<Preparation of phosphor sample>
Using Y ₂ O ₃ , Gd ₂ O ₃ , Al ₂ O ₃ , Eu ₂ O as a starting material and AlF ₃ as a flux material, these were weighed to a predetermined amount, and rotated using a planetary ball mill. Mix for 30 minutes at 200 rpm. Water or ethanol was used as the solvent. This mixed solution was sufficiently dried, and the dried powder was fired at 1300 ° C. to 1400 ° C. for 4 hours in the air.
<Measurement of luminance and chromaticity>
The phosphor samples of Examples and Comparative Examples were irradiated with vacuum ultraviolet light having a wavelength of 146 nm in a vacuum, and the emission in the visible region was measured.
Table 1 shows the composition ratio, luminance (Y), and chromaticity (x, y) of the produced phosphor. Y is the luminance Y in the International Lighting Commission XYZ color system, and is a relative value to the sample number 22. In Table 1, samples marked with * are comparative examples, and sample numbers 19 and 20 are Y (P, V) O ₄ : Eu, (Y, Gd) ₂ O ₃ : Eu red phosphor.

表１から明らかなように、組成比が本発明の組成範囲内にある蛍光体は、真空紫外光励起による輝度が高く、赤色発光の色純度が良い（色度ｘ値が小さく、ｙ値が大きい）。中でも、０≦ａ≦０．３７，０．０５≦ｂ≦０．１０，０．９５≦ｃ≦１．０５の組成範囲内にある蛍光体（試料番号３〜５、９〜１０、１３〜１６）では、特に輝度が高く、色度も良好である。尚、実施例の蛍光体試料に対し、真空中で波長１４６ｎｍの真空紫外光をパルス照射し、可視領域の発光強度が１／１０に減衰する時間（１／１０残光時間）を測定したところ、試料番号１９、２０の蛍光体と同程度の短残光特性であった。
試料番号１３、１４、１５、１９、２０と同様の赤色蛍光体を使用し、上述した交流面放電型ＰＤＰの例と同様にして図１の構成を有するＰＤＰを作製した。
ＰＤＰ作製後の輝度および色度（ｘ，ｙ）を表２に示す。このとき、パネル輝度は試料番号２４に対する相対値である。パネルは赤色１色固定表示とした。なお、表２において＊印を付した試料は比較例である。

As is clear from Table 1, the phosphor having a composition ratio within the composition range of the present invention has high luminance due to vacuum ultraviolet light excitation and good color purity of red light emission (the chromaticity x value is small and the y value is large). ). Among them, phosphors (sample numbers 3 to 5, 9 to 10, 13 to 10) in the composition ranges of 0 ≦ a ≦ 0.37, 0.05 ≦ b ≦ 0.10, 0.95 ≦ c ≦ 1.05 16) has particularly high luminance and good chromaticity. The phosphor sample of the example was irradiated with a pulse of vacuum ultraviolet light having a wavelength of 146 nm in vacuum, and the time during which the emission intensity in the visible region was attenuated to 1/10 (1/10 afterglow time) was measured. The afterglow characteristics were comparable to those of the phosphors of sample numbers 19 and 20.
A red phosphor similar to that of Sample Nos. 13, 14, 15, 19, and 20 was used, and a PDP having the configuration shown in FIG.
Table 2 shows the luminance and chromaticity (x, y) after fabrication of the PDP. At this time, the panel luminance is a relative value with respect to the sample number 24. The panel has a fixed red color display. In Table 2, samples marked with * are comparative examples.

表２から明らかなように、本発明による蛍光体を使用して作製したパネルでは、試料番号２４、２５の蛍光体を使用して作製したパネルに比べ輝度が高い。これは、試料番号２４、２５の蛍光体を使用して作製した場合では、粉体に比べ輝度が低下するのに対し、本発明による蛍光体を使用して作製した場合では、輝度が低下しないためである。

As is clear from Table 2, the panel produced using the phosphor according to the present invention has higher luminance than the panel produced using the phosphors of sample numbers 24 and 25. This is because when the phosphors of sample numbers 24 and 25 are used, the luminance is lower than that of the powder, whereas when the phosphors according to the present invention are used, the luminance does not decrease. Because.

  By using the phosphor of the present invention, it is possible to provide a high-efficiency plasma display panel having a short afterglow time and high luminance and color purity. The phosphor of the present invention can also be applied to uses such as fluorescent lamps (eg, electrodeless fluorescent lamps) and fluorescent panels.

10 PDP
20 Front panel 21 Front panel glass 22 Y electrode (display electrode)
23 X electrode (display electrode)
24 Front-side dielectric layer 25 Protective layer 26 Back panel 27 Back panel glass 28 Address electrode 29 Back-side dielectric layer 30 Bulkhead 31 Phosphor layer (R)
32 Phosphor layer (G)
33 Phosphor layer (B)
34 Discharge space 220 Transparent electrode 221 Bus line 230 Transparent electrode 231 Bus line

Claims (3)

A plasma display panel comprising a red phosphor layer emitting visible light by vacuum ultraviolet rays,
The red phosphor layer is
General formula (1-ab) YO _3/2 · aGdO _3/2 · bEuO _3/2 · cAlO _3/2 (0 ≦ a ≦ 0.47, 0.05 ≦ b ≦ 0.15, 0.90 A plasma display panel comprising a phosphor represented by ≦ c ≦ 1.10. 2. The plasma display panel according to claim 1, wherein, in the general formula, 0 ≦ a ≦ 0.37, 0.05 ≦ b ≦ 0.10, 0.95 ≦ c ≦ 1.05. General formula (1-ab) YO _3/2 · aGdO _3/2 · bEuO _3/2 · cAlO _3/2 (0 ≦ a ≦ 0.47, 0.05 ≦ b ≦ 0.15, 0.90 ≦ c ≦ 1.10).

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