KR20030080143A - Fabrication Method for Backplate of Plasma Display Panel - Google Patents

Abstract

PURPOSE: A method is provided to reduce costs and procedures for manufacturing a phosphor screen, while achieving improved discharge efficiency and luminous efficiency. CONSTITUTION: A method comprises a first step of preparing a rear substrate; a second step of forming an inclined barrier rib on the rear substrate through a screen printing method; and a third step of forming a phosphor screen by depositing a phosphor on the inclined barrier rib by using an inkjet printer and sintering the resultant structure. The inkjet printer includes a nozzle plate(207) having a plurality of nozzle holes(203); a substrate arranged in the vicinity of the nozzle plate; a piezo-electric member(202); a piezo-actuator for driving the piezo-electric member in such a manner that the phosphor liquid is sprayed through the nozzle holes from an ink chamber(205); a diaphragm(208) for forming a passage of the phosphor liquid when a pressure is applied to the ink chamber by the piezo-electric member; and a power unit for applying a signal for driving the piezo-actuator.

Description

Fabrication Method for Backplate of Plasma Display Panel

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a plasma display panel for use in a display device, and more particularly to a method for forming partition walls and phosphor films in a back plate of a plasma display panel.

In recent years, while high expectations for high-quality and large-screen televisions, including digital TVs, have been increasing, the development of displays suitable for them in the fields of each display such as CRT, liquid crystal display (LCD) and plasma panel (hereinafter referred to as PDP). This is going on.

PDPs are not suitable for large screens larger than 40 inches in that depth and weight increase depending on the size of the screen. In addition, although LCD has excellent performance of low power consumption and low driving voltage, there is a technical difficulty in manufacturing a large screen and there is a limit in viewing angle.

On the other hand, the PDP can realize a large screen, and 63-inch products have already been developed.

Fig. 1 shows a cross-sectional view of one discharge cell unit of a typical AC driven PDP.

The PDP is generally arranged in parallel with the front cover plate 10 and the back plate 20 facing the electrodes on the surface, and the gap between the two plates is partitioned by the partition wall 30, and the partition wall ( The phosphor layer 40 of red, green, and blue is formed in the groove between the 30 and the partition wall 30, and the discharge gas is sealed.

The manufacture is performed by forming the phosphor layer 40 in the groove of the back plate 20 on which the partition wall 30 is disposed, and superimposing the front cover plate 10 thereon to seal the discharge gas.

These PDPs are roughly classified into a direct current type (DC type) and an alternating current type (AC type) by a driving method.

In the DC type, the electrode is exposed to the discharge space, whereas in the AC type, a dielectric glass layer is disposed on the electrode.

A discharge gas composed of He, Ne, and Xe is contained in a discharge cell of the PDP, and ultraviolet rays generated from Xe excite the phosphor through a discharge phenomenon to generate visible light.

In order to increase the discharge efficiency, the space inside the discharge cell should be wide, and the area to which the phosphor is coated should also be wide to increase the luminous efficiency of the phosphor.

On the other hand, a screen printing method is generally applied as a method for applying the phosphor.

In the case of the screen printing method, the phosphor paste is printed several times to fill the partition walls and dried at 120 to 150 ° C. three times for RGB, and then fired at 350 to 450 ° C.

The screen printing method is a simple process using a simple and inexpensive equipment, but the printing thickness is about 20㎛ thick, there is a problem that the discharge efficiency is worsened because the space in the discharge cell is narrowed.

Accordingly, the present invention has been made to solve the above problems, and the object of the present invention is to increase the discharge efficiency and the luminous efficiency of the PDP by widening the inner space of the discharge cell and the phosphor coating area.

Fig. 1 shows a cross-sectional view of one discharge cell unit of a typical AC driven PDP.

2 is a schematic flowchart of a backplane process of an AC type PDP according to the present invention.

3A to 3C illustrate a process of forming barrier ribs and phosphors in a backplane process of a PDP according to the present invention.

4A to 4C are cross-sectional views of a partition wall manufacturing process by the screen printing method.

5A and 5B show yet another form of PDP partition wall according to the present invention.

Fig. 6A is a sectional view in which a partition wall is formed by sand blasting and a phosphor film is formed by ink jet printing.

Fig. 6B is a cross sectional view of a barrier rib and a phosphor film formed by screen printing;

* Explanation of symbols for main parts of the drawings

100 glass 101 data electrode

102: dielectric 103: printing plate

104: squeegee 105: bulkhead paste

107: partition 201: phosphor droplets

202: piezoelectric 203: nozzle hole

204 phosphor film 205 ink chamber

207: nozzle plate

Features of the backplane manufacturing method of the PDP according to the present invention for achieving the above object is a plasma display panel backplane manufacturing method, comprising: a first step of preparing a backplane; A second step of forming an inclined partition wall on the back substrate by screen printing; And a third step of forming a phosphor film by applying and firing a phosphor by an inkjet printing apparatus on the inclined partition wall.

The inclined partition wall is characterized in that it has a narrow and flat surface from the rear plate to the front plate, for example, the inclined partition wall has a stepped, inverted T-shape, triangular structure having a flat surface.

The inkjet printing apparatus includes a nozzle plate composed of a plurality of nozzle holes; A substrate disposed to be adjacent to the nozzle plate so as to be adjacent to each other and to form an ink supply path and an ink chamber; Piezoelectric body; A piezoelectric driver for driving the piezoelectric body such that phosphor droplets in the ink chamber are injected through the nozzle hole; A diaphragm for forming a passage through the phosphor droplet when the pressure is applied to the ink chamber by the piezoelectric body; It comprises a power supply unit for applying a signal for driving the piezoelectric actuator.

The action according to the characteristics of the present invention is to make the partition wall narrower from the rear plate to the front plate of the PDP by using the screen printing method, thereby securing more discharge space than the non-inclined partition wall, By forming the photo bulkhead to have a flat surface such as a staircase, it is possible to increase the discharge efficiency and the phosphor emission efficiency by maximizing the phosphor coating area of the electrode side of the front panel of the PDP by utilizing the point that the phosphor is well formed on a flat surface. When the phosphor film is applied, the phosphor film can be thinly formed using an inkjet printing method, thereby further securing a space in the discharge cell, thereby further increasing discharge efficiency and phosphor emission efficiency.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings.

Referring to the accompanying drawings, a preferred embodiment of a method for manufacturing a backplane of a PDP according to the present invention will be described.

2 is a schematic flowchart of a backplane process of an AC type PDP according to the present invention.

First, the washed glass substrate is prepared (S100), and a data electrode is formed on the substrate (S200).

In addition, a dielectric is formed on the substrate to protect the data electrode and reflect light passing backward during discharge (S300), and a barrier rib is formed by screen printing on the dielectric, and then inkjet between the barrier ribs. The phosphor is coated by the printing apparatus (S500).

3A to 3C illustrate a process of forming barrier ribs and phosphors in a backplane process of a PDP according to the present invention.

As shown in Fig. 3A, the partition wall 107 is printed in multiple layers by the screen printing method.

At this time, when the next printing, the width of the partition 107 is narrower than the first printed layer to make the shape of the staircase. This is to maximize the space inside the discharge cell and to increase the phosphor coating area to be formed later.

The partition wall manufacturing process by the screen printing method is as shown in Figs. 4A to 4C.

That is, the data electrode 101 is formed on the glass 100, the dielectric 102 is formed thereon, and then, as shown in FIG. 4A, the printing plate 103 is placed on the printing plate. The printing partition wall paste 105 is pushed on the 103 with a squeegee 104 to pass through the opening of the printing plate 103 for screen printing.

Then, as shown in Figure 4b, after drying at a temperature of 50 ~ 200 ℃, the process of screen printing on the first formed partition wall is performed by the height of the desired partition wall 107.

Thereafter, as shown in FIG. 4C, the baking is performed at about 350 to 700 ° C. to complete the partition 107.

When the barrier rib manufacturing process is completed, as shown in FIG. 3B, the barrier rib 107 is formed by using an inkjet print head having a structure in which droplet drops are formed and discharged by piezoelectric compression. The phosphor droplet 201 is dropped in between to fill the space between the partition walls 107, and then fired as shown in Fig. 3C to obtain a thin phosphor film 204 of about 5 to 10 mu m.

As shown in Fig. 3B, the inkjet printer apparatus is provided such that the head of the inkjet printer is adjacently adjacent to the nozzle plate 207, which is composed of one or more nozzle holes 203, parallel to the nozzle plate 207. And a substrate (not shown) forming the ink supply path (not shown) and the ink chamber 205, the piezoelectric body 202, and a metal or ceramic, and pressurize the ink chamber 205 by the piezoelectric body 202. When this is applied, an inkjet printer head composed of a diaphragm 208, a manifold, or the like, which forms a passage for the phosphor droplet to pass therethrough, and the phosphor droplet 201 in the ink chamber 205 is injected through the nozzle hole 203. And a piezoelectric actuator (not shown) for driving the piezoelectric member 202 and a power supply unit (not shown) for applying a signal for driving the piezoelectric driver.

The power supply unit includes a signal generator, a voltage regulator, and a power supply.

As described above, in the inkjet printing method of the piezoelectric drive method, when power is applied to the piezoelectric drive unit, the piezoelectric member 202 is applied with pressure to the ink bumper 205 to form a phosphor (comprising a phosphor and an organic binder) near the nozzle hole 203. By ejecting and ejecting the droplet 201, the phosphor droplet 201 is scanned between the partition walls 107 to form the phosphor film 204 having a desired pattern.

Then, the solvent and organic components are volatilized and combusted in the phosphor droplet 201 through firing to leave only the phosphor component. At this time, the phosphor thickness remaining in the phosphor droplet 201 is adjusted to control the phosphor thickness remaining after the firing.

That is, in the inkjet printing method, by controlling the amount of phosphor in the phosphor droplet 201, the thickness of the phosphor after drying can be made as thin as about 5 to 10 [mu] m, and the space in the discharge cell can be increased to increase the discharge efficiency.

However, since the phosphor has a specific gravity and a very large particle size of about 2 to 3 μm, the phosphor may be precipitated to the bottom between the partition walls 107 during drying, so that the phosphor may not be evenly applied between the partition walls 107. As a result, the phosphor coating area may be reduced, which may lower luminous efficiency.

Therefore, since the present invention forms the partition wall 107 in a step shape as shown in FIG. 3C, since the phosphor precipitates on the step even when the phosphor is precipitated, the phosphor film 204 having a uniform thickness as a whole can be formed. By forming the partition wall, it is possible to secure the space of the discharge cell, expand the phosphor film coating area, and secondly form the phosphor film 204 thinly by the inkjet printing method. As a result, the phosphor coating area and the discharge cell space are secured widely. You can do it.

In addition, since the inkjet printing method sprays the RGB phosphor droplet 201 and forms the phosphor film 204 through firing, the process is very simple, and since it is possible to spray a predetermined amount only where desired by low-cost equipment, waste of material Very little economical.

The number of nozzles of the inkjet printer head may have 1-1200, and the size of the head nozzle has 10-300um.

The ink droplet containing the phosphor is composed of an inorganic pigment and an organic substance. As the blue ink material of the phosphor, an inorganic pigment containing BaMgAl ₁₀ O ₁₇ : Eu is used, and as a red ink material of the phosphor, (Y · Gd) BO ₃ : An inorganic pigment containing Eu is used, and an inorganic pigment containing BaAl ₁₂ O ₁₉ : Mn or ZnSiO ₄ : Mn is used as the green ink material of the phosphor.

5A and 5B illustrate another form of the PDP partition wall according to the present invention, and may have various forms such as an inverted T-shape and a triangle, in addition to the staircase.

6A is a cross-sectional view in which a partition wall is formed by sand blasting and a phosphor film is formed by ink jet printing.

6B is a cross-sectional view of the partition wall and the phosphor film formed by the screen printing method.

First, as shown in Fig. 6A, when the partition wall 107 is formed by sand blasting, it is difficult to form a step shape having a flat surface, and the partition wall 107 is formed to be inclined. When the phosphor film 204 is applied, it is difficult to form the phosphor film toward the partition wall 107 and the bottom side is relatively thick, so that not only the area of the phosphor film 204 is reduced but also the discharge cell space is narrowed, thereby decreasing efficiency. .

6B, even when the partition wall 107 is formed by the screen printing method, the phosphor film 204 is formed due to the high viscosity of the phosphor paste when the phosphor is formed through the screen printing method without using the inkjet printing method. Since the thickness of the thickened space in the discharge cell is the same as that obtained through the existing process, an improved effect cannot be expected.

As described above, the plasma display panel backplane manufacturing method according to the present invention has the following effects.

By applying the inkjet printing method to the PDP phosphor film manufacturing process, there is an effect of simplifying the phosphor film manufacturing process and reducing the cost.

In addition, it is possible to increase the discharge efficiency and the luminous efficiency by maximizing the discharge cell internal space and the phosphor coating area using the inkjet printing method.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

Claims (4)

In the plasma display panel back panel manufacturing method, A first step of preparing a rear substrate; A second step of forming an inclined partition wall on the back substrate by screen printing; And a third step of forming a phosphor film by applying and firing a phosphor by an inkjet printing apparatus on the inclined partition wall. The method of claim 1, wherein the inclined partition wall has a narrow and flat surface from the rear plate to the front plate. The inkjet printing apparatus of claim 1, wherein the inkjet printing apparatus A nozzle plate composed of a plurality of nozzle holes; A substrate disposed to be adjacent to the nozzle plate so as to be adjacent to each other and to form an ink supply path and an ink chamber; Piezoelectric body; A piezoelectric driver for driving the piezoelectric body such that phosphor droplets in the ink chamber are injected through the nozzle hole; A diaphragm which forms a passage so that the phosphor droplet passes through when the pressure is applied to the ink chamber by the piezoelectric body; And a power supply unit applying a signal for driving the piezoelectric actuator. The method of claim 1, wherein the third step Placing a printing plate on the rear substrate; Pushing a printing partition wall paste on the printing platen and passing the opening of the printing platen to screen-print; Drying to a temperature of 50 to 200 ° C., and performing a screen printing process on the formed partition walls by a desired partition wall height; A method of manufacturing a back panel of a plasma display panel, comprising the steps of completing a partition by firing at 350 to 700 ° C.