KR20080022670A - Dielectric composition for plasma display panel and plasma display panel using the same - Google Patents

Abstract

A dielectric composition for plasma display panels is provided to ensure low firing temperature sufficient to prevent thermal deformation of a soda-lime glass substrate during a manufacturing step of a plasma display panel. A dielectric composition for plasma display panels comprises 50-75wt% of PbO and 5-30wt% of B2O3. The dielectric composition further comprises 25wt% or less of SiO2. A plasma display panel includes a soda-lime glass substrate(110) on which electrodes(120,130) are formed; and a dielectric layer(140) which is formed on the substrate to cover the electrodes, wherein the dielectric layer is formed of the dielectric composition.

Description

Dielectric Composition for Plasma Display Panel and Plasma Display Panel using The Same}

1 is a structural diagram showing a unit cell of a plasma display panel of the present invention

2 is a process flowchart showing a process for forming a dielectric layer for a plasma display panel using the printing method of the present invention.

<Description of Symbols in Drawings>

110: front substrate 120, 130: display electrode

120a, 130a: transparent electrode 120b, 130b: bus electrode

140: dielectric layer 150: protective layer

210: back substrate 220: address electrode

230: white dielectric layer 240: partition wall

250: phosphor layer

TECHNICAL FIELD The present invention relates to a plasma display panel, and more particularly, to a plasma display panel dielectric composition and a plasma display panel using such a dielectric composition.

Plasma Display Panel (Plasma Display Panel) is an electronic device that displays an image by using plasma discharge. Plasma display panel applies a predetermined voltage to an electrode disposed in the discharge space of the PDP so that plasma discharge occurs between them. An image is formed by exciting a phosphor layer formed in a predetermined pattern by vacuum ultraviolet (VUV) generated at the time.

The plasma display panel is a high distortion glass of the PD-200 is used as the front substrate and back substrate. However, the high distortion glass of the PD-200 has a high price, which is a significant limitation in reducing manufacturing costs in the manufacture of plasma display panels, which are becoming more competitive.

In order to overcome such disadvantages of the high-distortion glass of PD-200, the use of soda-lime glass is actively being considered. This is because soda-lime glass is only about 1/6 of the PD-200, which is advantageous in terms of unit cost. Therefore, studies on the use of soda-lime glass substrates have been actively conducted to improve the price competitiveness of the overall plasma display panel.

However, due to the low thermal characteristics of the soda-lime glass substrate, it has emerged as an important task to keep the soda-lime glass substrate in a stable glass state without causing thermal deformation during the manufacturing process of the plasma display panel.

That is, the soda-lime glass, which is mainly used as the substrate for the plasma display panel, is advantageous in terms of unit cost, and thus heat deformation occurs when heated to about 540 ° C. or higher. However, the existing dielectric composition used in the manufacture of the plasma display panel has a temperature required for its firing (hereinafter referred to as "baking temperature") of more than 540 ℃, the temperature necessary for the firing process is essential to the dielectric layer formation That is, the firing temperature was required to be higher than 540 ℃, there was a problem that the thermal deformation of the soda-lime glass is inevitable during the firing process due to such a high firing temperature.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a plasma display panel which can ensure a sufficiently low firing temperature so that thermal deformation of a soda-lime glass substrate does not occur during the manufacturing of the plasma display panel. It is to provide a dielectric composition for.

Another object of the present invention is to provide a dielectric composition for a plasma display panel that can not only ensure a sufficiently low firing temperature so that thermal deformation of a soda-lime glass substrate does not occur during the manufacturing of the plasma display panel, but also has excellent light transmittance characteristics. It is.

Another object of the present invention is to provide a plasma display including a dielectric layer made of a dielectric composition for plasma display panel capable of ensuring a sufficiently low firing temperature so that thermal deformation of a soda-lime glass substrate does not occur during the manufacture of a plasma display panel. To provide a panel.

Still another object of the present invention is to provide a plasma including a partition wall formed by using a dielectric composition for plasma display panel as a mother glass, which can ensure a sufficiently low firing temperature so that thermal deformation of the substrate does not occur in the manufacturing process of the plasma display panel. It is to provide a display panel.

It is still another object of the present invention to include a white dielectric layer formed by using a dielectric composition for a plasma display panel that can ensure a sufficiently low firing temperature in order to prevent thermal deformation of a substrate in a plasma display panel manufacturing process. It is to provide a plasma display panel.

As an aspect of the present invention for achieving the above object, 50 to 75% by weight of PbO; And 5 to 30% by weight of B ₂ O ₃ is provided.

Preferably, the dielectric composition for plasma display panel further includes 25 wt% or less of SiO ₂ and / or 5 wt% or less of Al ₂ O ₃ in order to improve light transmittance.

As another aspect of the present invention for achieving the above object, a soda-lime glass substrate with an electrode formed; And a dielectric layer formed on the substrate to cover the electrode, wherein the dielectric layer includes 50 to 75 wt% PbO and 5 to 30 wt% B ₂ O ₃ .

As another aspect of the present invention for achieving the above object, a substrate; And a partition wall formed on the substrate, wherein the partition wall has 50 to 75 wt% of PbO; And 5 to 30% by weight of a composition comprising B ₂ O ₃ is provided as a plasma glass panel.

As another aspect of the present invention for achieving the above object, a substrate; And a white dielectric layer formed on the substrate, wherein the white dielectric layer comprises 50 to 75 weight percent of PbO; And 5 to 30% by weight of a composition comprising B ₂ O ₃ is provided as a plasma glass panel.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

In the accompanying drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. On the other hand, when a part such as a layer, film, region, plate, etc. is formed or positioned on another part, it is formed directly on the other part and not only in direct contact but also when another part exists in the middle thereof. It should also be understood to include.

As shown in FIG. 1, the plasma display panel of the present invention has a pair of transparent electrodes 120a and 130a made of indium tin oxide (ITO) in one direction on a front substrate 110 formed of soda-lime glass. And display electrodes 120 and 130 formed of bus electrodes 120b and 130b made of a conventional metal material, covering the display electrodes 120 and 130, and covering the dielectric layer 140 and MgO on the entire surface of the front substrate 110. The passivation layer 150 is sequentially formed.

Looking at the formation process of the dielectric layer 140 in more detail with reference to Figure 2, first, 50 to 75% by weight of PbO and 5 to 30% by weight of B ₂ O ₃ is mixed (S100).

PbO should be added at least 50% by weight because it is effective in lowering the vitrification temperature (Tg) of the dielectric composition while maintaining the electrical properties of the dielectric composition, but when excessively added to more than 75% by weight causes a decrease in light transmittance. It is preferably contained in 50 to 75% by weight.

B ₂ O _{3, which} is effective as a tree planting agent, is for improving the glass forming ability and preferably has a content of 5 to 30% by weight, which exceeds 30% by weight because B ₂ O ₃ increases the vitrification temperature of the dielectric composition. In this case, it is difficult to lower the vitrification temperature of the dielectric composition to a desired range, the water resistance of the composition is lowered, and when it is less than 5% by weight, glass formation of the dielectric composition becomes difficult.

In addition, it is preferable to further add up to 25% by weight of SiO ₂ and / or up to 5% by weight of Al ₂ O ₃ as an additive for preventing crystallization of the dielectric composition and consequently improving the light transmittance characteristics of the dielectric composition.

The mixed dielectric composition was melted in a crucible (S200), and the glass of the molten dielectric composition was cooled to form a thin plate-shaped frit, which was pulverized and then d ₅₀ = 2-5 μm using an aliquot. To obtain a glass powder (S300). The glass powder thus obtained is mixed with a vehicle and / or a binder to form a paste (S400), and the dielectric layer 140 is formed on the front substrate 110 by a conventional printing method using the paste. ) Is formed (S500). Meanwhile, the dielectric layer 140 may be formed on the front substrate 110 by manufacturing a dry film based on the paste and laminating it. When the dielectric layer 140 is formed as described above, the dielectric layer 140 is finished by firing (S600).

When using the dielectric composition according to the present invention, the temperature required for the firing process, that is, the firing temperature can be adjusted to less than 540 ° C. Therefore, by using the dielectric composition of the present invention by lowering the firing temperature to less than 540 ℃ side effects that may occur in the front substrate 110 during the firing process, that is, the thermal deformation of the soda-lime glass substrate that may occur at 540 ℃ or more It will be avoided.

The protective layer 150 is formed on the dielectric layer 140 formed using MgO.

Meanwhile, an address electrode 220 is formed on one surface of the back substrate 210 formed of soda-lime glass in a direction crossing the display electrodes 120 and 130, and covers the address electrode 220. The white dielectric layer 230 is formed on the entire surface of 210. The white dielectric layer 230 formed on the front surface of the back substrate 210 is made of a glass having a composition and composition ratio of the dielectric composition of the present invention for the dielectric layer 140 formed on the front substrate 110. desirable. The white dielectric layer 230 formed on the front surface of the back substrate 210 is also formed by a printing method or a film laminating method, followed by a firing process, in which a soda-lime glass substrate that may occur at 540 ° C. or higher. This is because the thermal deformation should be prevented.

The partition wall 240 is formed to be disposed between the address electrodes 220 above the white dielectric layer 230. The partition wall 240 is also formed on the front substrate 110 of the present invention for the same reason as the white dielectric layer 230. It is preferable that the composition having the composition and the composition ratio of the dielectric composition for the dielectric layer 140 to be formed is made of matrix glass. Although the stripe-type partition wall 240 is illustrated in FIG. 1, the stripe-type partition wall 240 may be well-typed or delta-typed.

A phosphor layer 250 of red (R), green (G), and blue (B) is formed between each partition wall 240.

The points where the address electrodes 220 on the back substrate 210 and the display electrodes 120 and 130 on the front substrate 110 cross each other constitute a part of the discharge cell.

An address voltage is applied between the address electrode 220 and one display electrode 120 or 130 to perform an address discharge, thereby forming a wall voltage in the cell where the discharge has occurred, and again between the pair of display electrodes 120 and 130. By applying the sustain voltage, sustain discharge is generated in the cells in which the wall voltage is formed. As the vacuum ultraviolet rays generated by the sustain discharge excite and emit the corresponding phosphors, visible light is emitted through the transparent front substrate 110 to realize the screen of the plasma display panel.

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

Example  One

PbO, B ₂ O ₃ , SiO ₂ , and Al ₂ O ₃ were mixed to prepare a dielectric composition, with the weight percent of each composition being 63 wt%, 27 wt%, 8 wt%, and 2 wt%, respectively.

Example  2

Dielectric composition under the same conditions as in Example 1 except that the wt% of PbO, B ₂ O ₃ , SiO ₂ , and Al ₂ O ₃ are 65 wt%, 25 wt%, 8 wt%, and 2 wt%, respectively. Was prepared.

Example  3

Dielectric composition under the same conditions as in Example 1 except that the wt% of PbO, B ₂ O ₃ , SiO ₂ , and Al ₂ O ₃ were 67 wt%, 23 wt%, 8 wt%, and 2 wt%, respectively. Was prepared.

Example  4

Dielectric composition under the same conditions as in Example 1 except that the weight percentages of PbO, B ₂ O ₃ , SiO ₂ , and Al ₂ O ₃ were 69%, 21%, 8%, and 2% by weight, respectively. Was prepared.

Example  5

Dielectric composition under the same conditions as in Example 1 except that the wt% of PbO, B ₂ O ₃ , SiO ₂ , and Al ₂ O ₃ were 71 wt%, 19 wt%, 8 wt%, and 2 wt%, respectively. Was prepared.

The results of measuring the firing temperature, dielectric constant, and light transmittance of each of the samples of Examples 1 to 5 thus prepared are shown in Table 1 below.

PbO (wt%) B ₂ O ₃ (wt%) SiO ₂ (wt%) Al ₂ O ₃ (wt%) Firing temperature (℃) permittivity Light transmittance (%) (thickness: 40㎛) Example 1 63 27 8 2 <540 11.3 ＞ 65 Example 2 65 25 8 2 <530 12.1 ＞ 65 Example 3 67 23 8 2 <520 12.5 ＞ 65 Example 4 69 21 8 2 <510 12.9 ＞ 65 Example 5 71 19 8 2 <510 13.6 ＞ 65

As can be seen in Table 1, the dielectric composition of Examples 1 to 5 can be seen that the firing temperature is lowered in proportion to the amount of PbO added. That is, for the samples according to the embodiment of the present invention, all of the required firing temperatures were 540 ° C. or lower, and particularly in Examples 4 and 5, only the firing temperature of 510 ° C. or lower was required. It hardly generates deformation. Furthermore, in Examples 4 and 5, the coefficient of thermal expansion of the composition was increased to approximate the coefficient of thermal expansion of the soda-lime glass substrate, thus preventing distortions that may be caused by the difference in coefficient of thermal expansion between the dielectric layer and the soda-lime glass substrate. To prevent it.

As can be seen from the above experiment, by adding PbO, the vitrification temperature or firing temperature of the dielectric composition can be lowered in proportion to the content thereof, and in particular, when 8.0 wt% or more of PbO is added, the soda-lime substrate can be Not only do little thermal deformation occur, but also the coefficient of thermal expansion of the dielectric composition is increased.

On the other hand, when Li ₂ O was used instead of PbO, even when the content was 5.7 wt%, crystallization of the dielectric composition was caused. On the other hand, in the case of using Na ₂ O, even if the content is 9.9% by weight, the firing temperature can be lowered without causing crystallization, whereas in the case of Li ₂ O, the crystallization is caused even when the content is only 5.7% by weight. It can be seen that the maximum content that can be added to Na ₂ O is much higher than Li ₂ O. Although not described in the above examples, the maximum content of Na ₂ O that can lower the firing temperature without crystallization was about 12.0 wt%.

As described above, according to the present invention, by adding an appropriate amount of PbO to a Zn-based dielectric composition requiring a high firing temperature, the firing temperature can be lowered without occurrence of crystallization, and thus, a soda-lime glass substrate during the firing process It is possible to prevent thermal deformation from occurring.

In addition, the dielectric composition according to the present invention may have a thermal expansion coefficient that matches the thermal expansion coefficient of the soda-lime glass substrate, thereby preventing warpage due to a difference in the thermal expansion coefficient.

As a result, inexpensive soda-lime glass substrate and Zn-based dielectric composition can be used together, thereby improving the price competitiveness of the plasma display panel as a whole.

Claims (10)

50 to 75 weight percent PbO; And A dielectric composition for plasma display panel comprising 5 to 30% by weight of B ₂ O ₃ . The dielectric composition of claim 1, further comprising SiO ₂ but not more than 25 wt%. The dielectric composition of claim 1, further comprising Al ₂ O ₃ , but not more than 5 wt%. 4. The dielectric composition of claim 3, further comprising SiO ₂ , wherein the composition further comprises 25 wt% or less. A soda-lime glass substrate having electrodes formed thereon; And And a dielectric layer formed on the substrate to cover the electrode, wherein the dielectric layer comprises 50 to 75 wt% PbO and 5 to 30 wt% B ₂ O ₃ . The plasma display panel of claim 5, wherein the dielectric layer further comprises SiO ₂ but is 25 wt% or less. The plasma display panel of claim 5, wherein the dielectric layer further comprises Al ₂ O ₃ , but not more than 5 wt%. The plasma display panel of claim 7, wherein the dielectric layer further comprises SiO ₂ , but further includes 25 wt% or less. Board; And A plasma display panel comprising a partition wall formed on the substrate, wherein the partition wall is manufactured using the composition glass according to any one of claims 1 to 4 as a mother glass. Board; And A plasma display panel comprising a white dielectric layer formed on the substrate, wherein the white dielectric layer is manufactured using the composition of any one of claims 1 to 4 as a mother glass.

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