JPH0750274B2 - Liquid crystal display element - Google Patents

Description

TECHNICAL FIELD The present invention relates to a liquid crystal display device used in word processors, portable personal computers, TVs, etc., and in particular, a gap between substrates is made uniform over the entire surface of the substrate, and The present invention relates to a liquid crystal display element that prevents the generation of bubbles when left at a low temperature, and is particularly suitable for a large liquid crystal display device.

[Conventional technology]

Generally, in a liquid crystal display device, a pair of substrates having electrodes are made to face each other with electrode surfaces facing each other, a spacer is provided between the substrates to form a predetermined gap, and a peripheral portion is held by a sealing material and liquid crystal is sealed in the gap. It will be done. In the liquid crystal display device, the thickness of the liquid crystal layer is usually about 5 to 15 μm, and if this gap is not uniformly maintained, color unevenness occurs on the display surface and display quality deteriorates. Therefore, the spacer plays an important role in determining the display quality. As the spacer, a fibrous rigid spacer or a particulate elastic spacer was used alone. However, the display area is 10 square
When a liquid crystal display element is manufactured in which a fibrous rigid spacer is placed in the liquid crystal using a large substrate of cm or larger, the gap between the substrates becomes almost uniform, but bubbles are generated when left at low temperature and display quality is extremely high. It was bad. Further, there is a liquid crystal display element using a particulate elastic spacer instead of the fibrous rigid spacer in order to solve the above-mentioned drawbacks, but no bubbles are generated when left at a low temperature, but the gap between the substrates is the rigid member. The unevenness was larger than the gap in the spacer, and the display quality was poor.

Further, JP-A-57-70520 discloses a spacer having a low softening point by mixing a rigid spacer and a spacer having a lower softening point than the rigid spacer and spraying the mixture on a substrate coated with an insulating film to heat the spacer. A configuration in which the gap is made uniform by melting and fixing the insulating film is disclosed.
That is, in the above-mentioned publication, as a spacer having a low softening point, a polymer spacer having a melting point of about 200 ° C., which has a melting point of 350 ° C. or lower of the glass that is a substrate material, is used, and after spraying on the substrate, a pair of The substrate is sealed. At this time, the polymer spacer is melted and the insulating film formed on the substrate and the polymer spacer are melted and fixed to each other so that the distance between the substrates is uniform.

[Problems to be solved by the invention]

However, in the above publication, the curing temperature of the sealing material is about 120 ° C.
On the other hand, there is a problem that the spacer melting temperature becomes too high, and it is difficult to control the melting temperature of the polymer spacer, so that the seal baking apparatus under pressure / heating cannot be simplified.

The object of the present invention is to solve the above-mentioned drawbacks, to provide a liquid crystal display device with a uniform gap and without generating bubbles, and by producing a liquid crystal display device without applying a temperature higher than the curing temperature of the sealing material, An object is to provide a liquid crystal display device with improved display quality.

[Means for solving problems]

The structure of the present invention for achieving the above object is as follows.

A liquid crystal display device in which a pair of substrates on which electrodes are formed face each other, a spacer is arranged between the substrates to form a predetermined gap, and the periphery is held by a sealing material, and liquid crystal is sealed in the gap. In the above, the spacer is a mixed spacer of finely divided fibrous rigid spacers and particulate elastic spacers.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of a liquid crystal display device according to the present invention in which two kinds of spacers having different diameters are inserted in a liquid crystal, and FIG. 2 is a sectional view of FIG. One substrate 1 with a pair of transparent electrode films
The glass fiber spacer 4 (diameter 7 μm ± 0.5 μm, length 20 μm to 200 μm as a fibrous rigid spacer
m) and, as a particulate elastic spacer, a particulate plastic bead spacer 5 (diameter 8 μm ± 0.5 μm) showing a value closer to the linear expansion coefficient of liquid crystal than the rigid spacer was sprayed at a ratio of about 1: 1. The epoxy-based sealant 3 is screen-printed on the other substrate 2, both substrates are overlaid, and the sealant 3 is heated and baked at an appropriate temperature of about 120 to 150 ° C. and a pressure of about 1 kg / square cm. Pressurize with. By injecting and sealing the liquid crystal 6 through the injection hole 3a formed in the substrate 2 by cutting out a part of the sealing material 3 in the gap between the substrate 1 and the substrate 2 of the liquid crystal display substrate thus obtained. In the produced liquid crystal display device, the gap between the substrates became almost uniform, and no bubbles were generated when left at a low temperature of -30 ° C for about 48 hours.

That is, in the liquid crystal display element according to the present invention, the spacer is used without being melted, the gap between the substrates is regulated by the rigid spacer, and the generation of bubbles is prevented by the elastic spacer having a diameter larger than that of the rigid spacer. , JP-A-57
-The rigid spacers disclosed by -70520 and the spacers with a low softening point are mixed and sprayed onto the substrate coated with an insulating film, and the spacers with a low softening point and the insulating film are melted and fixed to make the gap uniform. Has a different configuration from that obtained.

〔The invention's effect〕

As described above, according to the present invention, by inserting two kinds of irregular spacers in the gap between the substrates of the liquid crystal display device,
The gap between liquid crystal display elements can be made uniform, and the display area is especially 400
A large liquid crystal display element having a size of square cm or more can be made uniform, and bubbles can be prevented from being generated when left at a low temperature, and pixel dropout due to bubbles, which is a major factor that reduces the yield of the liquid crystal display element, can be prevented.

[Brief description of drawings]

FIG. 1 is a plan view of a liquid crystal display device of the present invention in which two types of odd-shaped spacers are inserted in a gap between substrates, and FIG.
It is sectional drawing of a figure. 1, 2 ... Substrate with electrodes 3 ... Sealing material 4 ... Glass fiber spacer 5 ... Plastic bead spacer 6 ... Liquid crystal

Claims (1)

[Claims] 1. A pair of substrate surfaces having electrodes are opposed to each other,
A spacer is arranged between the substrates to form a predetermined gap, and the inner periphery of the facing substrate is held by a sealing material,
In a liquid crystal display device having a liquid crystal sealed in the gap,
The spacer is a mixture of finely divided fibrous rigid body spacers and particulate elastic body spacers, and the central diameter of the fibrous rigid body spacers is smaller than the central diameter of the particulate elastic body spacers. Liquid crystal display device characterized by the above.