JPH05185582A - Screen printing process and screen printing apparatus - Google Patents

Abstract

PURPOSE:To eliminate defects in orientation occurring to printing to sealing resin by minimizing pressure applied to areas requiring no printing when executing the printing. CONSTITUTION:A squeegee 11 for a screen printing apparatus is made in a cylindrical shape and a cut-out part is provided to a part of such squeegee. When executing the printing, the cylindrical squeegee 11 having the cut-out part on a part thereof is detached from a screen plate 12 by turning the squeegee on areas requiring no printing of the screen plate, and thereby pressure applied to the areas requiring no printing of the screen plate 12 can be minimized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screen printing method and a screen printing apparatus. In particular, it relates to a screen printing method and a screen printing apparatus used for manufacturing a liquid crystal panel.

[0002]

2. Description of the Related Art Liquid crystal panels have been applied to word processors, liquid crystal televisions and the like, and have been greatly expected as various display devices.

Further, in the trend of improving display quality, there is a trend toward higher density and larger screen. This LCD panel has 2
The structure is such that a liquid crystal is sandwiched between a pair of glass substrates. At this time, it is necessary to hold the two glass substrates at regular intervals. For this reason, a method in which a thermosetting or photo-curing resin called a sealing resin is kneaded with beads or fibers having a constant diameter and formed on the peripheral portion of the panel by a screen printing method is generally used. Usually, the squeegee used at this time is a linear squeegee in the longitudinal direction.

[0004]

With the increase in screen size of liquid crystal panels, in the method of forming the above-mentioned seal resin by screen printing, the screen plate also becomes large in size. On the other hand, the necessary portion of the sealing resin is only the peripheral portion of the substrate as in the case of the small screen. For this reason, in reality, an extra pressure (printing pressure) is applied to the display portion unrelated to the seal resin. The pressing of the screen plate may cause deterioration of orientation due to a mesh mark on the screen, which causes a problem of deterioration of display quality.

As a method of improving this, a method of drawing a seal resin only on a necessary portion by using a dispenser can be considered, but this method has a problem that productivity is lowered.

According to the present invention, when the seal resin is printed, a pressure (printing pressure) is applied only to a necessary portion (peripheral portion), and the pressure applied to the display portion by the printing is reduced as much as possible, so that the orientation generated in the display portion. An object of the present invention is to provide a high-quality liquid crystal panel that suppresses deterioration and has no display defects.

[0007]

As a printing method, a squeegee having a notch in a part of a cylindrical squeegee is rotated in accordance with the pattern of a screen plate, so that the squeegee of the squeegee near the pattern and on the pattern is rotated. Apply pressure.
Further, the squeegee has a cylindrical shape, and a notch is provided in a part thereof.

[0008]

The squeegee used for screen printing has a cylindrical shape, and a notch is provided in a part of the squeegee, so that pressure is applied only to a necessary portion when printing the seal resin,
In the display section independent of the sealing resin, the pressing of the squeegee against the screen plate can be minimized. As a result, it is possible to prevent orientation deterioration or orientation failure that occurs during printing of the seal resin.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A screen printing method and a screen printing apparatus according to embodiments of the present invention will be described below with reference to the drawings.

The screen printing method and the screen printing apparatus of the present invention can be used, for example, for printing a seal resin on a liquid crystal panel. That is, two glass substrates each having an electrode formed in an arbitrary pattern and having an alignment film such as polyimide are bonded to each other, and a liquid crystal substance is injected into the gap,
A liquid crystal panel is manufactured. At this time, when the two substrates are bonded together, a thermosetting or photocurable resin called a sealing resin is formed only on the peripheral portion of the substrate on one side of the substrate by screen printing, and the two substrates are bonded together. To match.

Specific embodiments will be described below with reference to the drawings. (FIG. 1) is a perspective view showing an outline of a screen printing apparatus used in an embodiment of the present invention. 11 is a squeegee, 1
2 is a screen plate and 13 is ink. Further, (FIG. 2) is a front view of the screen plate 12. Reference numeral 21 is a printing portion, 22 is a non-printing portion, and 23 is an area where the screen plate is pressed by a squeegee.

First, the ink 13, that is, a one-component thermosetting epoxy resin in which glass beads of 5.0 μm are dispersed is placed on the screen plate 12, and the squeegee 11 is used for screen printing. At this time, while the printing portion 21 is present in almost the entire area of the screen squeegee 11 in the longitudinal direction of the squeegee 11, the notched portion of the squeegee 11 is brought into contact with the screen squeegee 12 without rotating the squeegee 11. Was translated in the direction of the arrow.

Next, the printing portion 21 is provided only in the peripheral portion of the screen plate 12 and the non-printing portion 22 is formed in the central portion, and the squeegee 11 is held until the cutout portion of the squeegee 11 is separated from the screen plate 12. Rotated. In this state, the squeegee 11 was continuously rotated in the arrow direction without rotating the squeegee 11. That is, in the area where the non-printing portion 22 is located at the center of the screen plate 12, only both end portions of the squeegee 11 are pressed against the screen plate 12.

Further, when the squeegee is moved in the moving direction 15, the printing portion 21 is present almost all over the longitudinal direction of the squeegee 11. From about 2 cm before this, the squeegee 11 is rotated to cut the squeegee 11. The seal plate was printed by pressing the screen plate 12 with the entire squeegee 11 such that the not-so-noted portion was brought into contact with the screen plate 12. That is, the shaded area in (Fig. 2)
An area 23 where the screen plate 12 is pressed by the squeegee 11.

In this way, when a liquid crystal panel was produced using the substrate on which the sealing resin had been printed, a good liquid crystal panel having no alignment defect in the display portion was obtained.

The comparative example (FIG. 3) is a perspective view showing the outline of the screen printing apparatus used in the comparative example. Reference numeral 31 is a squeegee, 32 is a screen plate, and 33 is ink.

In the same manner as in the embodiment, the ink 33, that is, the one-component thermosetting epoxy resin in which 5.0 μm glass beads are dispersed is placed on the screen plate 32, and the squeegee 31 is used to transfer to the glass substrate. At this time, from the beginning to the end of printing, the squeegee 31 was always brought into contact with the screen plate 32, and pressure was applied to complete printing of the sealing resin. In this way, when a liquid crystal panel was produced using the substrate on which the sealing resin had been printed, there were some cases where the display part had an alignment defect due to the mesh of the screen plate. In particular, when the squeegee is pressed with a high pressure, orientation defects may occur.

[0018]

As described above, according to the present invention, a squeegee having a notch in a part of a cylindrical squeegee is rotated in accordance with a pattern of a screen printing plate of a screen printing device, so that a sealing resin for manufacturing a liquid crystal panel is obtained. During printing, pressure can be applied only to the necessary parts. As a result, it is possible to minimize unnecessary pressure on the display portion unrelated to the seal resin printing, prevent alignment deterioration or alignment failure that occurs during seal resin printing, and provide a high-quality liquid crystal panel. Become.

[Brief description of drawings]

FIG. 1 is a perspective view showing an outline of a screen printing apparatus according to an embodiment of the present invention.

FIG. 2 is a front view showing a screen plate used in an example of the present invention.

FIG. 3 is a perspective view showing an outline of a screen printing apparatus of a comparative example of the present invention.

[Explanation of symbols]

 11 squeegee 12 screen plate 13 ink 14 squeegee moving direction 21 printing part 22 non-printing part 23 area where the screen plate is pressed by the squeegee 31 squeegee 32 screen plate 33 ink 34 squeegee moving direction

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Midori Tsukane 1006, Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (4)

[Claims] 1. A squeegee having a notch in a part of a cylindrical squeegee is rotated in accordance with a pattern of a screen plate to apply the pressing force of the squeegee in the vicinity of the pattern and on the pattern. Screen printing method. 2. A screen printing apparatus comprising an ink supply section, a screen plate having an arbitrary pattern formed thereon, and a squeegee, wherein the squeegee has a cylindrical shape, and a cutout is provided in a part thereof. And a screen printing device. 3. The screen printing apparatus according to claim 2, wherein the ink used for screen printing is a thermosetting resin. 4. The screen printing apparatus according to claim 2, wherein the ink used for screen printing is a photocurable resin.