JPS5943201B2 - How to collect liquid crystal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for manufacturing a liquid crystal cell, and more particularly to a method for recovering excess liquid crystal deposited around an injection hole of a cell during injection of liquid crystal.

Usually, a liquid crystal cell has a pair of electrode plates arranged facing each other at a predetermined distance, the periphery is sealed with a sealant, liquid crystal is injected through an injection hole provided at one or two places in the sealing part, and then the injection hole is sealed. created by stopping.

The method for injecting liquid crystal is to place the cell and liquid crystal in a container that can be vacuum degassed, and after vacuum degassing, bring the liquid crystal into contact with the injection hole of the cell, and then fill the container with inert gas at normal pressure. There is a method of injecting by purging, and a method of injecting by bringing liquid crystal into contact with one of two injection holes and suctioning from the other.

In either injection method, in order to prevent bubbles from entering during injection, it is necessary to contact excess liquid crystal, resulting in excess liquid crystal adhering to the vicinity of the injection hole. Conventionally, the excess liquid crystal that adhered around this injection hole was wiped off, but the amount of excess liquid crystal that adhered was 1 to 2 times the amount that was actually injected into the cell.
Not only was it twice as expensive, it was extremely wasteful, but it also had many drawbacks in terms of safety, health, and pollution.

The present invention has been made in view of the above problems, and provides a method for recovering excess liquid crystal that adheres around the cell injection hole when liquid crystal is injected.

That is, in the present invention, when injecting liquid crystal into a liquid crystal cell, excess liquid crystal attached around the injection hole of the cell is brought into contact with a holder,
Extracting the liquid crystal absorbed by the holder using an organic solvent,
The method is characterized in that the solvent and liquid crystal are then separated. In the present invention, when the holder is brought into contact with excess liquid crystal that has adhered around the injection hole when liquid crystal is injected, the liquid crystal is absorbed into the holder due to capillary action.

The liquid crystal absorbed by the carrier is extracted using a highly soluble organic solvent such as benzene, methanol, acetone, ethanol, toluene, and chlorofluorocarbon. The extracted liquid crystal is separated and recovered by vacuum degassing of the organic solvent, and is reused. In the present invention, the holder may be anything that has a capillary effect, such as quartz fiber,
Examples include fibers such as glass fibers, carbon fibers, metal fibers, asbestos fibers, slag fibers, and organic fibers, or yarns processed from these fibers, tape mats, cloths, sponges, etc., but in particular, any material that does not contaminate liquid crystals may be used. The shape is obtained,
A quartz fiber yarn with good capillary effect is preferred. EXAMPLE As shown in FIG. 1, the injection hole 2 of the cell 1 was brought into contact with the liquid crystal 3, and vacuum injection was carried out.

At this time, the excess liquid crystal 4 attached to the periphery of the injection hole 2 of the cell 1 is absorbed by the yarn 5 of the quartz fiber (Fig. 2), and the excess liquid crystal around the injection hole 2 is removed (Fig. 3). Injection hole 2
was sealed with sealant 6 to obtain a liquid crystal cell. In this manufacturing process, the amount of liquid crystal absorbed into the quartz fiber yarns 5 was approximately 70% of the excess liquid crystal.

The liquid crystals absorbed into the quartz fiber yarn were extracted using benzene, and then the benzene and liquid crystals were separated by degassing the benzene using a vacuum rotary evaporator, and approximately 60% of the excess liquid crystals were recovered. . As explained above, according to the present invention, excess liquid crystal attached around the injection hole of the cell can be recovered by absorbing it into the holder instead of wiping it off in the conventional method. ,
Liquid crystal waste has been significantly reduced.

Furthermore, if a fibrous holder is used, liquid crystal deposited in the recesses between the substrates can be completely absorbed.

[Brief explanation of the drawing]

1 to 4 are side views showing the manufacturing process. 1...Cell, 2...Injection hole, 3...
...LCD, 4...Extra liquid crystal, 5...
- Holding body, 6...Sealing agent.

Claims (1)

[Claims] 1. When injecting liquid crystal into a liquid crystal cell, excess liquid crystal attached around the injection hole of the cell is brought into contact with a holder, and the liquid crystal absorbed by the holder is extracted using an organic solvent. and then separating the solvent and the liquid crystal. 2. The liquid crystal recovery method according to claim 1, wherein the holding body is made of fiber or processed fiber. 3. The liquid crystal recovery method according to claim 2, wherein the holding body is a quartz fiber yarn.