KR20080040977A - Red phosphor for plasma display panel and plasma display panel comprising same - Google Patents

Abstract

A red phosphor for a plasma display panel(PDP), and a plasma display panel containing the phosphor are provided to improve color purity, brightness and lifetime characteristics. A red phosphor for a plasma display panel comprises 80-100 wt% of a first phosphor represented by Y(P, V)O4:Eu; and 0-20 wt% of a second phosphor represented by (Y, Gd)BO3:Eu. Preferably the red phosphor has a color coordinate whose x is 0.652-0.670. A plasma display panel is provided with a red phosphor layer which comprises the red phosphor; a green phosphor layer; and a blue phosphor layer.

Description

RED PHOSPHOR FOR PLASMA DISPLAY PANEL AND PLASMA DISPLAY PANEL COMPRISING SAME}

1 is a schematic view of a plasma display panel of the present invention;

2 is a graph showing the life characteristics of the red phosphors of Example 1 and Comparative Example 4 of the present invention.

[Industrial use]

The present invention relates to a red phosphor for a plasma display panel and a plasma display panel including the same, and more particularly, to a red phosphor for a plasma display panel having excellent color purity while maintaining luminance and lifespan characteristics, and a plasma display panel including the same. will be.

[Prior art]

In general, a plasma display panel (PDP) is a display device that realizes an image by using visible light generated by vacuum ultraviolet (VUV) radiation emitted from a plasma formed by gas discharge to excite a phosphor layer. The plasma display panel has a high resolution and large screen configuration, and has been spotlighted as a next generation thin display device.

A plasma display panel generally used at present is a reflective AC drive plasma display panel, and in the case of a bottom plate structure, a phosphor layer is formed on a partition wall.

Among the phosphors used in the phosphor layer, red phosphors include (Y, Gd) BO ₃ : Eu, Y (V, P) O ₄ : Eu, (Y, Gd) ₂ O ₃ : Eu or Y ₂ O ₃ : Eu Is being used.

It is an object of the present invention to provide a red phosphor for a plasma display panel having excellent color purity characteristics while maintaining the luminance and lifetime characteristics of the red phosphor.

Another object of the present invention is to provide a plasma display panel including the red phosphor.

In order to achieve the above object, the present invention provides more than 80% by weight, less than 100% by weight of the Y (P, V) O ₄ : Eu first phosphor and more than 0% by weight, less than 20% by weight of (Y, Gd) BO ₃ : Red phosphor for plasma display panel containing Eu 2nd phosphor is provided.

The present invention also provides a plasma display panel comprising a phosphor layer comprising a red phosphor layer, a green phosphor layer and a blue phosphor layer, wherein the red phosphor layer comprises the red phosphor.

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

The present invention relates to a red phosphor for a plasma display panel.

Conventionally, red phosphors include (Y, Gd) BO ₃ : Eu, Y (P, V) O ₄ : Eu, (Y, Gd) ₂ O ₃ : Eu or Y ₂ O ₃ : Eu, and in particular, (Y, Gd) BO ₃ : Eu is the most widely used because of its excellent brightness and lifetime characteristics. However, (Y, Gd) BO ₃ : Eu has a problem that the color purity is slightly lowered.

Therefore, in the present invention, in order to obtain a red phosphor having excellent color purity, the Y (P, V) O ₄ : Eu phosphor (hereinafter referred to as “the second phosphor”) is added to the (Y, Gd) BO ₃ : Eu phosphor (hereinafter referred to as “second phosphor”). 1 phosphor ") is provided to provide a red phosphor. In this case, it is preferable that the mixing ratio of the first phosphor and the second phosphor is more than 80 wt% and less than 100 wt%, and the second phosphor is used more than 0 wt% and less than 20 wt%. . Further, it is more preferable to use 85 wt% to 90 wt% of the first phosphor and 10 wt% to 15 wt% of the second phosphor. When the content of the first phosphor is 80% by weight or less, the color coordinate characteristic is deteriorated, which is not preferable. Since the second phosphor may be added even in a very small amount, only the minimum of 0% by weight may be used, and the maximum of 20% by weight may be used. When the mixing ratio of the first phosphor and the second phosphor satisfies the above range, there is no need to use a separate filter for removing Ne light.

As such, when the first phosphor is used in an amount exceeding 80% by weight, the color coordinate may be improved since the x coordinate of the color coordinate is moved toward the red side while maintaining the luminance at a similar level as the case where only the second phosphor is used. The color coordinate of the red phosphor of the present invention is x is 0.652 to 0.670, y is a value adjusted according to the x value.

Accordingly, it can be seen that the color coordinate of the red phosphor using only the second phosphor is moved toward the red color more than 0.638 to 0.643, which is an x value, thereby showing improved color purity.

Since the red phosphor of the present invention exhibits such improved color purity, the plasma display panel using the red phosphor of the present invention does not need to use a ne-cut filet for removing Ne light, which is conventionally used to improve color purity. . The filter for removing the Ne light was generally used to compensate for the fact that the color purity of the second phosphor is very poor when only the second phosphor is used, but this also caused a problem of lowering the red luminance. Therefore, the present invention can also solve the problem of luminance reduction caused by the use of a filter for removing such Ne light.

The red phosphor of the present invention is used to form a red phosphor film of a plasma display panel, and includes a phosphor layer including a red phosphor layer, a green phosphor layer, and a blue phosphor layer by using a red phosphor composition including the red phosphor of the present invention. In the plasma display panel to form a red phosphor layer.

The red phosphor composition comprises a vehicle together with the red phosphor of the present invention. The vehicle includes a binder resin and a solvent, and the binder resin is dissolved in the solvent. Examples of the binder resin and the solvent used to prepare the phosphor composition are as described below, but are not limited thereto.

As the binder resin, a cellulose resin, an acrylic resin, or a mixture thereof may be used. As the cellulose resin, for example, methyl cellulose, ethyl cellulose, propyl cellulose, hydroxy methyl cellulose, hydroxy ethyl cellulose, hydroxy propyl cellulose, hydroxy ethyl propyl cellulose, or a mixture thereof may be used. As said acrylic resin, For example, poly methyl methacrylate, poly isopropyl methacrylate, poly isobutyl methacrylate, or methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, Hexyl methacrylate, 2-ethyl hexyl methacrylate, benzyl methacrylate, dimethyl amino ethyl methacrylate, hydroxy ethyl methacrylate, hydroxy propyl methacrylate, hydroxy butyl methacrylate, phenoxy 2- Hydroxy propyl methacrylate, glycidyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, hexyl acrylate, 2-ethyl hexyl acrylate, benzyl acrylate, dimethyl amino ethyl acrylate , With hydroxy Acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, phenoxy copolymer, or a mixture of acrylic monomers such as 2-hydroxypropyl acrylate, glycidyl acrylate can be used. In some cases, the composition may comprise a small amount of inorganic binder. Preferably, the content of the binder resin may be about 2 to about 8% by weight based on the phosphor composition.

Alcohol, ether, ester or a mixture thereof may be used as the solvent, more preferably butyl cellosolve (BC), butyl carbitol acetate (BCA), terpine Terpineol or mixtures thereof may be used. If the content of the solvent is too high or too low, the flow characteristics of the composition is not appropriate, the process of forming a green phosphor layer may not be easy. In consideration of this point, the content of the solvent may be about 25 to about 75 wt% based on the phosphor composition.

The phosphor composition may further include other additives to improve flow characteristics, process characteristics, and the like. As the additive, for example, various additives such as a photosensitizer, a dispersant, a silicone-based antifoaming agent, a leveling agent, a plasticizer, an antioxidant, etc. may be used alone or in combination, all of which are commonly used in the art. Available to those with knowledge of

In addition, although an example of a plasma display panel using the green phosphor of the present invention is shown in FIG. 1, the structure of the plasma display panel of the present invention is not limited to FIG. Is a matter of course.

1 is a partially exploded perspective view showing a plasma display panel according to a first embodiment of the present invention.

As shown in FIG. 1, the plasma display panel of the present invention includes a first substrate 1 (rear substrate) and a second substrate 11 (front substrate) disposed substantially parallel to each other at arbitrary intervals.

A plurality of address electrodes 3 are formed on the first substrate 1 (back substrate) along one direction (Y direction in the drawing), and cover the address electrodes 3 to the first substrate 1. The first dielectric layer 5 is formed. A plurality of barrier ribs 7 are formed on the first dielectric layer 5 between the address electrodes 3 at predetermined heights and form a discharge space. The barrier ribs 7 may be open or closed as necessary. Can be formed. Red, green, and blue (B) phosphor layers 9 are located between the partitions 7. This red phosphor layer contains the red phosphor of the present invention. The green phosphor layer may include Zn ₂ SiO ₄ : Mn, YBO ₃ : Tb, (Zn, A) ₂ SiO ₄ : Mn (A is an alkali metal) or a mixture thereof, and the phosphor and BaAl ₁₂ O ₁₉ : Mn, (Ba, Sr, Mg) O.αAl ₂ O ₃ : Mn (α is 1 to 23), MgAl _x O _y : Mn (x is 1 to 10, y is 1 to 30), LaMgAl _x O _y : Tb, Mn (x is 1 to 14, y is 8 to 47), ReBO ₃ : Tb (Re is a rare earth element selected from the group consisting of Sc, Y, La, Ce, Gd, and combinations thereof) and their It is also possible to use a mixture of phosphors selected from the group consisting of combinations. When the mixture is used in this way, the green phosphor selected from the group consisting of Zn ₂ SiO ₄ : Mn, YBO ₃ : Tb, (Zn, A) ₂ SiO ₄ : Mn (A is an alkali metal) and mixtures thereof is 10 to 10. Preference is given to using in an amount of 70% by weight.

In addition, the blue phosphor layer includes BaMgAl ₁₀ O ₁₇ : Eu, CaMgSi ₂ O ₆ : Eu, CaWO ₄ : Pb, Y ₂ SiO ₅ : Eu, or a combination thereof.

One surface of the second substrate 11 (front substrate) facing the first substrate 1 includes a pair of transparent electrodes 13a and bus electrodes 13b in a direction crossing the address electrodes 3. The display electrodes 13 are formed, and the dielectric layer 15 and the passivation layer 17 are disposed on the entirety of the second substrate 11 while covering the display electrodes 13.

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)

A red phosphor was prepared by mixing 90 wt% of Y (P, V) O ₄ : Eu first phosphor and 10 wt% of (Y, Gd) BO ₃ : Eu second phosphor.

Dissolve 5% by weight of ethylene cellulose resin in 95% by weight of a mixed organic solvent of butyl carbitol acetate and terpineol (mixing ratio of 50:50 by volume), and add 40% by weight of the red phosphor to 60% by weight of the mixture to stir and Phosphor paste was prepared. The phosphor paste was applied to a discharge cell and then fired to form a red phosphor layer, thereby manufacturing a plasma display panel in a conventional manner.

(Example 2)

Example 1 except that the red phosphor prepared by mixing 95% by weight of the Y (P, V) O ₄ : Eu first phosphor and 5% by weight of (Y, Gd) BO ₃ : Eu second phosphor It carried out similarly.

(Example 3)

Example 1 except that a red phosphor prepared by mixing 85% by weight of the Y (P, V) O ₄ : Eu first phosphor and 15% by weight of (Y, Gd) BO ₃ : Eu second phosphor was used. It carried out similarly.

(Comparative Example 1)

Example 1 except that the red phosphor prepared by mixing 80% by weight of the Y (P, V) O ₄ : Eu first phosphor and 20% by weight of (Y, Gd) BO ₃ : Eu second phosphor was used. It carried out similarly.

(Comparative Example 2)

Example 1 except that the red phosphor prepared by mixing 50% by weight of the Y (P, V) O ₄ : Eu first phosphor and 50% by weight of (Y, Gd) BO ₃ : Eu second phosphor It carried out similarly.

(Comparative Example 3)

Example 1 and the above except that the red phosphor prepared by mixing 40% by weight of the Y (P, V) O ₄ : Eu first phosphor and 60% by weight of (Y, Gd) BO ₃ : Eu second phosphor It carried out similarly.

(Comparative Example 4)

The same procedure as in Example 1 was carried out except that only the (Y, Gd) BO ₃ : Eu phosphor was used as the red phosphor.

Red color coordinates and luminance were measured in the plasma display panel manufactured according to Examples 1 to 3 and Comparative Examples 1 to 3, and the results are shown together in Table 1 below.

First phosphor (%) Color coordinate (x) Brightness (%) Example 1 90 0.654 68 Example 2 95 0.655 66 Example 3 85 0.653 70 Comparative Example 1 80 0.652 72 Comparative Example 2 50 0.647 83 Comparative Example 3 40 0.649 79

As shown in Table 1, the red phosphors of Examples 1 to 3 and the red phosphors of Comparative Examples 1 to 3 showed similar brightness, but the color coordinates of the red phosphors of Examples 1 to 3 were higher than those of Comparative Examples 1 to 3. It is moved to the red side, it can be seen that color purity is superior to Comparative Examples 1 to 3.

In addition, the life characteristics of Example 1 and Comparative Example 4 were measured and the results are shown in FIG. 2. As shown in Figure 2, it can be seen that the red phosphor of Example 1 exhibits almost the same level of life characteristics as in Comparative Example 4.

From the results of Table 1 and FIG. 2, it can be seen that the red phosphors of Examples 1 to 3 exhibited excellent color purity while exhibiting the same luminance and lifetime characteristics as those of Comparative Examples 1 to 4.

All simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

The red phosphor of the present invention does not need to use a filter that is very excellent in color purity and removes Ne light while maintaining the same level of brightness and lifetime characteristics.

Claims (9)

Greater than 80 wt% and less than 100 wt% Y (P, V) O ₄ : Eu first phosphor; And More than 0 wt% and less than 20 wt% (Y, Gd) BO ₃ : Eu Second Phosphor Red phosphor for a plasma display panel comprising a. The method of claim 1, The red phosphor includes the first phosphor in an amount of 85 to 90% by weight, and the second phosphor in an amount of 10 to 15% by weight. The method of claim 1, The color coordinates of the red phosphor x is 0.652 to 0.670 red phosphor for the plasma display panel. A phosphor layer comprising a red phosphor layer, a green phosphor layer, and a blue phosphor layer, The red phosphor layer is Greater than 80 wt% and less than 100 wt% Y (P, V) O ₄ : Eu first phosphor; And More than 0 wt% and less than 20 wt% (Y, Gd) BO ₃ : Eu Second Phosphor To include Plasma display panel. The method of claim 4, wherein The red phosphor may include 85 to 90 wt% of the first phosphor and 10 to 15 wt% of the second phosphor. The method of claim 4, wherein The color coordinate of the red phosphor x is 0.652 to 0.670 plasma display panel. The method of claim 4, wherein The green phosphor layer includes a green phosphor selected from the group consisting of Zn ₂ SiO ₄ : Mn, YBO ₃ : Tb, (Zn, A) ₂ SiO ₄ : Mn (A is an alkali metal) and mixtures thereof. Plasma display panel. The method of claim 7, wherein The green phosphor is BaAl ₁₂ O ₁₉ : Mn, (Ba, Sr, Mg) O.AlAl ₂ O ₃ : Mn (α is 1 to 23), MgAl _x O _y : Mn (x is 1 to 10, y is 1 To 30), LaMgAl _x O _y : Tb, Mn (x is 1 to 14, y is 8 to 47), ReBO ₃ : Tb (Re is Sc, Y, La, Ce, Gd and combinations thereof) And a phosphor selected from the group consisting of a rare earth element selected) and a combination thereof. The method of claim 4, wherein The blue phosphor layer further comprises a blue phosphor selected from the group consisting of BaMgAl ₁₀ O ₁₇ : Eu, CaMgSi ₂ O ₆ : Eu, CaWO ₄ : Pb, Y ₂ SiO ₅ : Eu and mixtures thereof. panel.

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