KR20060057481A - Cleaning method and apparatus of pattern printing mask - Google Patents

Abstract

The present invention relates to a method and apparatus for cleaning a screen mask that can improve the degree of cleaning and the life of the screen mask.

The cleaning method of a pattern printing mask for printing a thin film paste according to the present invention on a substrate at least once includes removing foreign substances adhered to the pattern printing mask by contacting the front and rear surfaces of the pattern printing mask and the cleaning part. do.

Description

Cleaning method and apparatus for pattern printing mask {Cleaning Method And Apparatus Of Pattern Printing Mask}             

1A and 1B are cross-sectional views illustrating a method of manufacturing an electrode or a partition of a conventional plasma display panel.

FIG. 2 is a view for explaining a cleaning method of the screen mask shown in FIG. 1.

FIG. 3A is a view showing a change in tension of the screen mask shown in FIG. 2, and FIG. 3B is a view showing foreign matter adsorbed on the side and the front of the screen mask by the cleaning roller shown in FIG. 2.

4A and 4B are views for explaining a cleaning method of a screen mask according to the present invention.

FIG. 5 is a view showing a second cleaning unit used in place of the support member shown in FIG. 4B.

FIG. 6 is a cross-sectional view illustrating a plasma display panel having electrodes and partition walls formed using a screen mask cleaned by the cleaning method illustrated in FIG. 4.

<Description of Symbols for Main Parts of Drawings>                 

1,42 substrate 48,52 dielectric layer

50: shield 54: bulkhead

56 phosphor layer X: address electrode

Y: scan electrode Z: sustain electrode

32: opening 34: screen mask

38: foreign matter 40, 50: cleaning roller

42, 52: cleaning tape 46: support member

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for cleaning a mask for pattern printing, and more particularly, to a method and apparatus for cleaning mask for pattern printing which can improve the degree of cleaning and improve the life of the mask for pattern printing.

Plasma Display Panel (hereinafter referred to as "PDP") is a display device using visible light generated from a phosphor when ultraviolet light generated by gas discharge excites the phosphor. PDP is thinner and lighter than Cathode Ray Tube (CRT), which has been the mainstay of display means, and has the advantage of being able to realize high definition large screen. PDP is composed of a plurality of discharge cells arranged in a matrix form, one discharge cell constitutes a pixel of the screen.                         

A discharge cell of a conventional three-electrode AC surface discharge type PDP includes a top plate including scan electrodes and a sustain electrode of a sustain electrode pair formed on an upper substrate, and a bottom plate including an address electrode formed to cross the sustain electrode pair on a lower substrate. And a partition wall that provides a discharge space between the upper plate and the lower plate.

The PDP of this structure is selected by opposing discharge between the address electrode and the sustain electrode, and then maintains the discharge by the surface discharge between the pair of sustain electrodes. As the phosphor emits light by ultraviolet rays generated during the sustain discharge, visible light is emitted outside the cell. As a result, the discharge cells adjust the period during which the discharge is maintained to implement gray scale, and the PDP in which the discharge cells are arranged in a matrix form displays an image.

Meanwhile, any one of an address electrode, a sustain electrode pair, a phosphor layer, and a partition wall of the PDP is formed by the screen printing process shown in FIGS. 1A and 1B.

As shown in FIG. 1A, the screen mask 4 with the opening 2 on the substrate 1 is aligned. By placing an electrode paste, phosphor paste or barrier paste on the screen mask 4 and pressing with a squeegee, the electrode paste, phosphor paste or barrier paste is printed on the substrate 1 as shown in FIG. 1B. By repeating this, the thin film 6 including the electrode, the phosphor layer, or the partition wall of a desired height is formed.

The screen mask 4 used in such a screen printing process is cleaned through a cleaning process after printing an electrode paste, a phosphor paste or a partition paste about 1 to 10 times. As shown in FIG. 2, only the rear surface of the screen mask 4 that faces the substrate 1 is cleaned by the cleaning roller 10 in which the cleaning tape 12 is wound, and then the screen mask 4 is put into the screen printing process again.

In this case, as the number of times the screen mask 4 is printed increases, the degree of cleaning for cleaning the screen mask 4 using the cleaning tape 12 is lowered. In addition, the tension of the screen mask 4 is lowered as shown in FIG. 3A by the pressure in the cleaning roller 10 in which the screen mask 4 is wound around the cleaning tape 12 during cleaning. There is a problem that 4) is deformed. In addition, foreign matter adsorbed on the rear surface of the screen mask 4 when the rear surface of the screen mask 4 is cleaned is partially formed on the side and the front surface of the screen mask 4 by the pressure of the cleaning roller 10 as shown in FIG. 3B. Is adsorbed. When the screen mask 4 is re-inserted into the printing process, there is a problem that the thin film formed by the screen mask 4 is contaminated.

Accordingly, an object of the present invention relates to a cleaning method and apparatus for a pattern printing mask which can improve the degree of cleaning and also improve the life of the pattern printing mask.

In order to achieve the above object, the cleaning method of the pattern printing mask for printing the thin film paste according to the present invention on the substrate at least once is attached to the mask for pattern printing in contact with the front and back and the cleaning portion of the pattern printing mask. Characterized in that it comprises the step of removing the foreign matter.

The removing of the foreign matter adhered to the pattern printing mask by contacting the front and rear surfaces of the pattern printing mask and the cleaning part may include cleaning the back surface of the pattern printing mask through a first cleaning part; And cleaning the entire surface of the pattern printing mask through the second cleaning unit simultaneously with the cleaning process through the first cleaning unit.

Each of the first and second cleaning parts may include applying the same pressure to the pattern printing mask.

Each of the first and second cleaning units is characterized in that the cleaning tape is wound around the cleaning roller.

The first and second cleaning unit is characterized in that it comprises a step of removing the foreign matter by rotating while contacting the mask for pattern printing.

The pattern printing mask may be a screen mask having an opening so that the thin film paste is printed on the substrate.

The pattern printing mask may be used when manufacturing at least one of an electrode, a phosphor layer, and a partition of the plasma display panel.

In order to achieve the above object, the cleaning apparatus of the pattern printing mask for printing the thin film paste according to the present invention on the substrate at least once and the first cleaning unit for cleaning the pattern printing mask in contact with the back surface of the pattern printing mask; ; And a second cleaning unit which rotates simultaneously with the first cleaning unit and contacts the entire surface of the pattern printing mask to clean the pattern printing mask.

Each of the first and second cleaning units is characterized in that the cleaning tape is wound around the cleaning roller.

The pattern printing mask may be a screen mask having an opening so that the thin film paste is printed on the substrate.

The pattern printing mask may be used when manufacturing at least one of an electrode, a phosphor layer, and a partition of the plasma display panel.

Other objects and features of the present invention in addition to the above objects will become apparent from the description of the embodiments with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 4A to 6.

4A and 4B illustrate a method of cleaning a screen mask according to the present invention.

First, when the electrode paste or the barrier paste is printed at least once on the substrate, the foreign substance 38, which is the residue of the electrode face, the phosphor paste or the barrier paste, is adsorbed on the rear surface of the screen mask 34 as shown in FIG. 4A. In order to remove the foreign matter 38, the first cleaning roller 40 wound with the first cleaning tape 42 is rotated while being in contact with the back surface of the screen mask 34 as shown in FIG. 4B. Remove the foreign matter 38 attached to the back of the. At the same time, a second cleaning roller having the second cleaning tape 52 wound around the second cleaning tape 52 has foreign substances moved / adsorbed from the back surface of the screen mask 34 to the front and side surfaces of the screen mask 34 by the pressure of the first cleaning roller 40. It is removed by 50.

Instead of the second cleaning roller 50 on which the second cleaning tape 52 is wound, as shown in FIG. 5, the pressure equal to the pressure applied to the rear surface of the screen mask 34 is supported using the support member 46. It is applied to the front surface of the mask 34 to prevent the tension change of the screen mask 34.

As such, the cleaning method of the screen mask according to the present invention removes foreign substances adhering to the screen mask while applying the same pressure to the front and rear surfaces of the screen mask. Accordingly, the tension change of the screen mask can be prevented, and the contact area between the screen mask and the cleaning tape is improved, thereby improving the cleaning degree. In addition, it is possible to prevent the tension of the screen mask from being lowered, thereby improving the life of the screen mask.

FIG. 6 is a cross-sectional view illustrating a plasma display panel having electrodes and partition walls formed using a screen mask cleaned by the cleaning method illustrated in FIG. 4.

Referring to FIG. 6, the discharge cells of the PDP according to the present invention include the scan electrode Y and the sustain electrode Z formed on the upper substrate 40, and the address electrode X formed on the lower substrate 42. ).

Each of the scan electrodes Y and the sustain electrodes Z has a line width smaller than that of the transparent electrodes 44Y and 44Z and the transparent electrodes 44Y and 44Z, and is formed at one edge of the transparent electrodes 44Y and 44Z. Electrodes 46Y and 46Z. The transparent electrodes 44Y and 44Z are usually formed on the upper substrate 40 by indium tin oxide (ITO). The bus electrodes 46Y and 46Z are formed of a metal having high conductivity on the transparent electrodes 44Y and 44Z, thereby reducing the voltage drop caused by the transparent electrodes 44Y and 44Z having high resistance.

The upper dielectric layer 48 and the passivation layer 50 are stacked on the upper substrate 40 having the scan electrode Y and the sustain electrode Z side by side. Wall charges generated during plasma discharge are accumulated in the upper dielectric layer 48. The passivation layer 50 prevents damage to the upper dielectric layer 48 due to sputtering generated during plasma discharge and increases emission efficiency of secondary electrons. As the protective film 50, magnesium oxide (MgO) is usually used.

The lower dielectric layer 52 and the partition wall 54 are formed on the lower substrate 42 on which the address electrode X is formed, and the phosphor 56 is coated on the surfaces of the lower dielectric layer 52 and the partition wall 54. The address electrode X is formed in a direction crossing the scan electrode Y and the sustain electrode Z. The partition wall 54 is formed in parallel with the address electrode X to prevent ultraviolet rays and visible light generated by the discharge from leaking to the adjacent discharge cells. The phosphor 56 is excited by ultraviolet rays generated during plasma discharge to generate visible light of any one of red, green, and blue. Inert gas for gas discharge is injected into the discharge space provided between the upper and lower substrates 40 and 42 and the partition wall 54.

As described above, the method and apparatus for cleaning a screen mask according to the present invention removes foreign substances adhering to the screen mask while applying the same pressure to the front and rear surfaces of the screen mask. Accordingly, the tension change of the screen mask can be prevented, and the contact area between the screen mask and the cleaning tape is improved, thereby improving the cleaning degree. In addition, it is possible to prevent the tension of the screen mask from being lowered, thereby improving the life of the screen mask.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (11)

In the cleaning method of the pattern printing mask which prints a thin film paste on a board | substrate at least once, And removing the foreign matter adhering to the pattern printing mask by contacting the front and rear surfaces of the pattern printing mask and the cleaning part. The method of claim 1, Removing the foreign matter attached to the pattern printing mask by contacting the front and back and the cleaning unit of the pattern printing mask is Cleaning the back surface of the pattern printing mask through a first cleaning unit; And cleaning the entire surface of the pattern printing mask through the second cleaning unit simultaneously with the cleaning process through the first cleaning unit. The method of claim 2, And the first and second cleaning parts each apply the same pressure to the pattern printing mask. The method of claim 2, Each of the first and second cleaning parts is a cleaning method for a mask for pattern printing, characterized in that the cleaning tape is wound around the cleaning roller. The method of claim 2, And the first and second cleaning parts rotate to contact the pattern printing mask to remove the foreign matter. The method of claim 1, And the pattern printing mask is a screen mask having an opening so that the thin film paste is printed on the substrate. The method of claim 1, The pattern printing mask is a cleaning method for a pattern printing mask, characterized in that used in the production of at least one of the electrode, the phosphor layer and the partition wall of the plasma display panel. In the cleaning apparatus of the pattern printing mask which prints a thin film paste on a board | substrate at least once, A first cleaning unit which contacts the rear surface of the pattern printing mask to clean the pattern printing mask; And a second cleaning unit rotating at the same time as the first cleaning unit and in contact with the entire surface of the pattern printing mask to clean the mask for pattern printing. The method of claim 8, Each of the first and second cleaning parts is a cleaning device for a pattern printing mask, characterized in that the cleaning tape is wound around the cleaning roller. The method of claim 8, And the pattern printing mask is a screen mask having an opening so that the thin film paste is printed on the substrate. The method of claim 8, The pattern printing mask is a cleaning device for a pattern printing mask, characterized in that used in the production of at least one of the electrode, the phosphor layer and the partition wall of the plasma display panel.

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