JPH021819A - Production of dot matrix type liquid crystal display element - Google Patents

Abstract

PURPOSE:To prevent the destruction of oriented films at the time of rubbing and to improve yield by subjecting substrates to an inspection of the pattern defects of the electrode patterns, then subjecting only the non-defective substrates to formation of the same potential patterns, rubbing treatment, cell assembly, etc. CONSTITUTION:After plural pieces of the electrodes 2 are simultaneously formed on a sheet of the glass substrate 1, the substrate is inspected for the pattern defects by passing large current to the electrode patterns 2 or by other methods. The same potential patterns 3 which short-circuit the terminals 2a of the respective electrodes 2 from each other are formed on the substrate judged to be non-defective. The oriented film 4 is then formed on the patterns 2 exclusive of the terminal parts 2a and the surface thereof is rubbed in a specific direction. The two substrates which are subjected to the rubbing treatment and are integrated by orthogonally disposing the respective electrode patterns so as to face each other are cut t produce multiple pieces of the empty cells and to disconnect the same potential patterns 3. Liquid crystals are sealed into the cells in the final. Since the terminal parts 2a are short-circuited by the same potential patterns 3 prior to the rubbing treatment, the destruction of the oriented films is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a dot matrix liquid crystal display element in which alignment treatment is performed by a rubbing method.

[Conventional technology]

When manufacturing a dot matrix type liquid crystal display element (hereinafter referred to as LCD), first, a mixed oxide of indium and tin is deposited on a glass substrate using methods such as vapor deposition, sputtering, and dip methods. ITO is formed into a film, and this transparent ITO film is formed.
The TO film is etched to form a plurality of electrode patterns extending parallel to each other at a predetermined pitch. Next, an alignment film made of a dielectric thin film is formed by printing on the electrode pattern of the electrode substrate, and the surface of this alignment film is rubbed in a specific direction. After that, this electrode substrate and another electrode substrate on which an electrode pattern and an alignment film have been similarly formed and subjected to a rubbing treatment are made to face each other so that the electrode patterns are perpendicular to each other, and both electrodes are bonded through a sealing material. Attach the boards. Then, cut this to take out many empty cells,
A dot matrix type LC is created by filling the empty cell with liquid crystal.
Complete D.

Incidentally, the upper and lower electrode substrates of the dot matrix type LCD manufactured as described above have external dimensions of, for example, 250 mm.
400 or 640 elongated electrode patterns are formed within a range of mm x 180 mm, but adjacent electrode patterns of such fine patterns create a potential difference due to static electricity during rubbing, causing discharge, and the There was a risk that the alignment film would be partially destroyed due to heat generation.

Therefore, as disclosed in Japanese Patent Publication No. 57-56044, when forming an electrode pattern, a pattern with the same potential that short-circuits each electrode pattern is formed, and after the rubbing alignment process, the pattern with the same potential is separated and each A method has been proposed in which the electrode patterns are made independent. According to such conventional proposals, multiple electrode patterns formed on a glass substrate are short-circuited in advance, so even if static electricity accumulates during rubbing, no discharge occurs between adjacent electrode patterns, thereby preventing alignment film breakdown. can be prevented.

[Problem to be Solved by the Invention] By the way, since the electrode patterns of dot matrix type LCDs are minute, it is better to inspect the patterns for short circuits and disconnections before the rubbing process, and to perform similar inspections after the rubbing process or after cell assembly. It is more efficient than doing However, the conventional proposal described above forms an electrode pattern that is short-circuited to the same potential pattern in advance, so it is not possible to inspect whether the electrode pattern is good or bad until the same potential pattern is removed. Also, the yield was poor because rubbing treatment and cell assembly were required.

The present invention was made in view of these circumstances, and
The purpose is to create a dot matrix type LCD that can prevent alignment film damage during rubbing and improve yield.
The purpose of this invention is to provide a method for manufacturing the same.

[Means to solve the problem]

In order to achieve the above object, the present invention forms a plurality of electrode patterns, performs an inspection to detect pattern defects, and then creates an ITO pattern with the same potential that shorts the ends of each electrode pattern. It was formed using a conductive paste, and after the two electrode substrates were bonded together by a rubbing process, the same potential pattern was separated.

[Effect]

According to the above means, after inspecting for pattern defects, it is only necessary to perform the same potential pattern formation, rubbing treatment, cell assembly, etc. on non-defective products, so that the yield can be greatly improved.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

First, as shown in FIG. 1A, a plurality of elongated electrode patterns 2 are formed on a glass substrate 1 by a method such as vapor deposition or etching. These electrode patterns 2 are made of ITO, and the electrode patterns 2 for one cell extend parallel to each other at regular intervals. form.

Next, by passing a large current through the electrode pattern 2, inspect for pattern defects, that is, short circuits and disconnections between patterns.
For the products judged to be good in this inspection, Fig. 1 (B)
As shown in FIG. 2, a same potential pattern 3 is formed that short-circuits the terminal portions 2a of each electrode pattern 2. This potential pattern 3 is an ITO film with a film thickness of 500 to 600 people,
The method for forming it is to apply a conductive paste having the composition shown in Table 1 below by screen printing or the like, and then to bake it.

After forming the first layer, as shown in FIG. 1(C), an alignment film 4 made of a thin dielectric film is formed on the electrode pattern 2 except for the terminal portion 2a. The alignment film 4 is formed by applying ink by offset printing or the like and then baking it.

After the alignment film 4 is formed on one electrode substrate in this way, the surface of this alignment film 4 is rubbed in a specific direction, and the alignment film on the other electrode substrate (not shown) is also subjected to a rubbing treatment in the same manner.

Note that the same potential pattern 3 is formed on both electrode substrates.

Now, the two electrode substrates that have been subjected to the rubbing treatment are placed facing each other so that their electrode patterns are perpendicular to each other, and are placed in a sealing material (not shown) that has been applied to a position corresponding to the periphery of each cell. Paste together.

Once the two electrode substrates are integrated in this way, they are cut to obtain a large number of empty cells, and at the time of cutting, the same potential pattern 3 of both electrode substrates is 2 as shown in Fig. 1 (C).
Since each electrode pattern 2 is separated along the dotted chain line, each electrode pattern 2 becomes electrically independent.

Finally, a liquid crystal is sealed in the empty cell to complete a dot matrix type LCD.

As described above, in the above embodiment, since the terminal portions 2a of each electrode pattern 2 are short-circuited by the same potential pattern 3 before the rubbing process, there is a risk that discharge will occur between the adjacent electrode patterns 2 during the rubbing process. Therefore, destruction of the alignment film due to static electricity is prevented. Moreover, since the same potential pattern 3 is formed after forming the electrode pattern 2 and inspecting the pattern for defects, if the inspection result is determined to be defective, the same potential pattern 3 is formed in the subsequent process, that is, the formation of the same potential pattern. There is no need to carry out processes such as rubbing, cell assembly, etc., and therefore yields are greatly improved.

In the above embodiment, the alignment film 4 is formed after forming the same potential pattern 3, but the same potential pattern 3 may be formed after forming the alignment film 4 on the electrode pattern 2.

It is also possible to form the same potential pattern with silver paste, but the thickness of the silver paste is at least 6 to 7 μm.
This is relatively large, and also causes unevenness on the film surface, resulting in a film thickness of 7 μm or more in some parts, making it unsuitable for modern LCDs that require a minute cell gap of about 7 μm. In other words, if the same potential pattern is formed using a paste, the same potential pattern must be cut out before the two electrode substrates are bonded together, making it impossible to create a large number of empty cells. In other words, by forming the same potential pattern using ITO conductive paste,
A large number of cells can be produced while maintaining a small cell gap.

〔Effect of the invention〕

As explained above, according to the present invention, after inspecting the electrode pattern for pattern defects, it is only necessary to perform the same potential pattern formation, rubbing treatment, cell assembly, etc. on non-defective products, so the product yield can be greatly improved. Furthermore, since the same potential pattern is formed before the rubbing process, damage to the alignment film due to static electricity during rubbing can be prevented.Furthermore, since this same potential pattern is formed using an ITO conductive paste, microscopic Dot matrix type L with cell gap
It has remarkable effects, such as being suitable for manufacturing CDs.

[Brief explanation of the drawing]

FIGS. 1(A) to 1(C) are for explaining one embodiment of the present invention. FIG. 1(A) is a process diagram showing a state in which an electrode pattern is formed, and FIG. A process diagram showing a state in which a pattern is formed, and (C) of the same figure is a process diagram showing a state in which an alignment film is formed. ■... Glass substrate, 2... Electrode pattern, 2a... Terminal section, 3... Same potential pattern, 4... Alignment film . Agent Patent Attorney Kenji Department

Claims (1)

[Claims] Two electrode substrates each having a plurality of electrode patterns extending in parallel and an alignment film covering these electrode patterns are subjected to a rubbing treatment on the alignment film, and then the electrode patterns are orthogonal to each other. In a dot matrix type liquid crystal display element manufactured by bonding the two electrode substrates facing each other and then sealing liquid crystal between the two electrode substrates, the above method is used to form the plurality of electrode patterns and detect pattern defects. After the inspection, a same potential pattern that short-circuits the ends of each electrode pattern is formed using an ITO conductive paste, and after the above rubbing process is performed and the two electrode substrates are bonded together, the same potential pattern is formed. A method for manufacturing a dot matrix type liquid crystal display element characterized by separating it.