KR20050051330A - Blue phosphor for plasma display panel - Google Patents

Abstract

The present invention relates to a blue phosphor for a plasma display panel, the first phosphor comprising a Ba-based compound; And it provides a blue phosphor for a plasma display panel comprising a CaMgSi ₂ O ₆ : Eu second phosphor.

As described above, the blue phosphor of the present invention can provide a plasma display panel exhibiting improved lifetime characteristics and efficiency characteristics.

Description

Blue phosphor for plasma display panel {BLUE PHOSPHOR FOR PLASMA DISPLAY PANEL}

[Industrial use]

The present invention relates to a blue phosphor for a plasma display panel, and more particularly to a blue phosphor for a plasma display panel excellent in life characteristics.

[Prior art]

In general, a plasma display panel (hereinafter referred to as a "PDP") is a display device that generates a predetermined image by exciting phosphors by ultraviolet rays generated by gas discharge. Is in the spotlight.

The conventional general PDP structure is shown in FIG. Referring to FIG. 1, in the conventional general PDP structure, an address electrode 101 is formed along one direction (the x-axis direction of the drawing) on the back substrate 100 and covers the address electrode 101 to cover the back substrate 100. The dielectric layer 103 is formed on the front surface. A stripe pattern partition wall 105 is formed on the dielectric layer 103 so as to be disposed between each address electrode 101, and red, green, and blue colors are formed between the partition walls 105. The phosphor layer 107 is formed.

In addition, one surface of the front substrate 110 facing the rear substrate 100 may be provided with a pair of transparent electrodes 112 and bus electrodes 113 along a direction crossing the address electrode 101 (y-axis direction of the drawing). The discharge sustain electrode 114 is formed, and the dielectric layer 116 and the MgO passivation layer 118 are formed on the entire front substrate 110 while covering the discharge sustain electrode 114.

The point where the address electrode 101 on the rear substrate 100 and the discharge sustain electrode 114 on the front substrate 110 cross each other constitutes a discharge cell.

An address voltage Va is applied between the address electrode 101 and the discharge sustain electrode 114 to perform address discharge, and a sustain voltage Vs is applied between the pair of discharge sustain electrodes 114 to sustain discharge. The vacuum ultraviolet rays generated at this time excite the phosphor to emit visible light through the transparent front substrate 110 to implement the screen of the PDP.

The phosphor layer is formed using red, green, and blue phosphors, and among these, blue phosphors include Ba-based such as (Ba, Sr, Mg) O.Al ₂ O ₃ : Mn, which exhibits the highest luminous efficiency in the 147 nm region. Phosphor was used. However, as shown in FIG. 2, the Ba-based phosphor has a problem in that the luminance of the operation time is significantly reduced, that is, the lifespan characteristics are very poor. Therefore, in recent years, research has been conducted to improve not only the luminous efficiency of PDP but also such life characteristics, but it has not yet reached a satisfactory level.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a blue phosphor for a plasma display panel having excellent luminance retention.

Another object of the present invention is to provide a blue phosphor for a plasma display panel which can provide a plasma display panel having excellent life characteristics.

In order to achieve the above object, the present invention is a first phosphor comprising a Ba-based compound; And it provides a blue phosphor for a plasma display panel comprising a CaMgSi ₂ O ₆ : Eu second phosphor.

Hereinafter, the present invention will be described in more detail.

The present invention relates to a blue phosphor having improved luminance retention, that is, lifespan characteristics of a Ba-based phosphor, which has been widely used as a blue phosphor. The blue phosphor of the present invention includes a first phosphor containing a Ba-based compound and a CaMgSi ₂ O ₆ : Eu second phosphor.

The CaMgSi ₂ O ₆ : Eu (hereinafter referred to as "CaMgSi series phosphor") phosphor used as the second phosphor in the present invention has a strong resistance against ultraviolet rays compared to the Ba series phosphor, and thus has a good luminance retention and a good y-coordinate. However, the luminance is very low, about 70% of Ba-based phosphors.

In the present invention, a Ba-based phosphor having high luminance but poor life characteristics and a CaMgSi-based phosphor having good lifetime characteristics but low luminance may be mixed in an appropriate composition ratio to obtain a blue phosphor for plasma display panel having good luminance and lifetime characteristics. Therefore, the mixing ratio of the first phosphor and the second phosphor in the blue phosphor of the present invention is a very important factor, the preferred range is 70 to 30: 30 to 70% by weight, 50 to 40: 50 to 60% by weight desirable. If the content of the second phosphor is less than 30% by weight, the lifespan is lowered, which is undesirable. If the content of the second phosphor is greater than 70%, the luminance is lowered, which is not preferable.

Ba-based phosphor used as the first phosphor in the present invention may be used BaMgAl _x O _y : Eu (where x is an integer of 10 to 14, y is an integer of 17 to 23).

Hereinafter, preferred examples and comparative examples of the present invention are described. However, the following examples are only preferred embodiments of the present invention and the present invention is not limited to the following examples.

(Example 1)

50 wt% of BaMgAl ₁₀ O ₁₇ : Eu first phosphor and 50 wt% of CaMgSi ₂ O ₆ : Eu second phosphor were mixed to prepare a blue phosphor for a plasma display panel.

(Comparative Example 1)

CaMgSi ₂ O ₆ : Eu was used as a blue phosphor for plasma display panels.

(Comparative Example 2)

BaMgAl ₁₀ O ₁₇ : Eu was used as a blue phosphor for a plasma display panel.

The x color coordinate, the y color coordinate, the initial luminance efficiency (luminance / Y color coordinate) and the relative luminance of the blue phosphors of Examples 1 and Comparative Examples 1 to 2 were measured, and the results are shown in Table 1 below.

x color coordinate y color coordinate Relative brightness efficiency Comparative Example 1 0.147 0.043 50% 77% Comparative Example 2 0.147 0.067 100% 100% Example 1 0.147 0.05 75% 95%

As shown in Table 1, the blue phosphor of Example 1 is superior to the initial relative luminance and initial luminance efficiency compared to Comparative Example 1, and compared to the phosphor of Comparative Example 2, the initial luminance and initial efficiency is slightly reduced, but the y color coordinate As it is excellent, it can be seen that it shows more vivid blue color.

 In addition, the luminance efficiency according to the use time is shown in FIG. 3, and the luminance maintenance ratio, which is a lifespan characteristic, is shown in FIG. 3 and 4 show that the blue phosphor of Example 1 has a smaller decrease in luminance efficiency and excellent luminance retention than Comparative Example 1. FIG. Therefore, it can be seen from the Table 1 and FIGS. 3 and 4 that the phosphor of Example 1 is a blue phosphor satisfying all of initial luminance, efficiency, and lifetime characteristics.

As described above, the blue phosphor of the present invention can provide a plasma display panel exhibiting improved lifetime characteristics and efficiency characteristics.

1 is a perspective view schematically showing the structure of a plasma display panel.

2 is a graph showing the luminance retention, which is a lifespan characteristic of a conventional Ba-based blue phosphor.

3 is a graph showing the efficiency characteristics of the blue phosphors of Example 1 and Comparative Examples 1 and 2 of the present invention.

Figure 4 is a graph showing the life characteristics of the blue phosphor of Example 1 and Comparative Examples 1 and 2 of the present invention.

Claims (3)

A first phosphor comprising a Ba-based compound; And CaMgSi ₂ O ₆ : Eu 2nd phosphor Blue phosphor for a plasma display panel comprising a. The blue phosphor of claim 1, wherein the blue phosphor comprises 70 to 30 wt% of the first phosphor and 30 to 70 wt% of the second phosphor. The blue phosphor of claim 1, wherein the Ba-based compound is BaMgAl _x O _y : Eu (where x is an integer of 10 to 14 and y is an integer of 17 to 23).