JPS63225223A - Production of liquid crystal element - Google Patents

Abstract

PURPOSE:To secure orientation condition of liquid crystals in good condition without causing adverse effect on the liquid crystals due to a sealing resin for sealing an injecting port of the liquid crystals by injecting pieces of inactive resin under pressure through the injecting port after injecting the liquid crystals through the injecting port of the liquid crystals, then sealing the liquid crystals with the sealing resin. CONSTITUTION:A sealing material 3 is provided to three edges of a square superposed surface of an upper 1, and lower 2 substrates. A space where this sealing material is absent is used as an injecting port 4 of liquid crystals. Then, liquid crystals such as ferroelectric liquid crystals having chiral smectic C phase are injected from the injecting port 4. Since, in this case, the injecting port 4 is so wide as corresponding to one edge of the superposed surface of the upper and lower substrates 1, 2, even such ferroelectric liquid crystals having high viscosity can be injected quickly. When the injection of the liquid crystals is finished, pieces of an inactive resin 5 are forced under pressure through the injecting port 4, then the injecting port 4 is closed. By this process, dissolution of the sealing resin into the liquid crystal is prevented almost completely, preventing also defective orientation near the injecting port, also.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a liquid crystal element using a liquid crystal of a ferroelectric liquid crystal shade.

[Conventional technology]

Liquid crystal devices using ferroelectric liquid crystal exhibiting a chiral smectic C phase have been widely used because this ferroelectric liquid crystal has a bistable state, has display memory properties, and has high-speed response. Capacitive display, memory type display, ai 'A Hikari 1! It is being applied to ivy and other plants.

However, the viscosity of ferroelectric liquid crystals is generally much higher than that of normal nematic liquid crystals, and the liquid crystal 1 inside the liquid crystal cell is
It takes a long time for one person to process the liquid crystal, and as a result, in a portion far from the liquid crystal (liquid crystal) 1 inlet, there is a problem in which the composition of the liquid crystal separates or its alignment state changes.

To solve this problem, the liquid crystal injection port should be made wider and the liquid crystal (liquid crystal)
[Making it easier to enter] - The idea is to reduce the time spent by one person.

(Problem to be solved by the invention) However, although it is possible to shorten the injection time with this method of widening the liquid crystal injection port to shorten the liquid crystal injection time, it is possible to shorten the injection time by expanding the liquid crystal injection port. Since the sealing resin is used for sealing, the contact area between the sealing resin and the liquid crystal becomes large, and the alignment of the liquid crystal near the liquid crystal temperature increases due to reasons such as the sealing resin melting into the liquid crystal. It was discovered that new problems occurred, such as defects occurring, and alignment defects progressing over time from the liquid crystal injection port to the inside of the cell, and the alignment defects could spread to the display area of the device. .

This invention was made in view of the above circumstances, and there is no adverse effect on the liquid crystal due to the sealing resin that seals the liquid crystal injection port.
The object of the present invention is to provide a method for manufacturing a liquid crystal device that can ensure a good alignment state of liquid crystal.

[Means for solving problems]

In this invention, after injecting the liquid crystal from the liquid crystal injection port, a piece of inert resin is press-fitted into the liquid crystal injection port, and then the liquid crystal is sealed with the resin.

Hereinafter, an example of a method for manufacturing a liquid crystal device according to the present invention will be explained with reference to FIGS. 1 and 2. Reference numeral 1 in the figure is a lower substrate. The descending plate 1 is made of a glass plate or the like, and a transparent electrode and an alignment film (not shown) are provided on its inner surface. A similar upper substrate 2 is superimposed on this lower substrate 1. The upper and lower substrates 1 and 2 are integrally formed with each other through spacers (not shown) made of photocurable acrylic resin or epoxy resin, which are provided in a band shape around the overlapping surfaces of the upper and lower substrates. In the manufacturing method of this example, the moon material 3 is provided on three sides of the rectangular overlapping surfaces of the upper and lower substrates 1.2, and the sealing material 3 is provided on the remaining one side.
is not provided, and the gap portion where the sealing material 3 does not exist is used as the liquid crystal injection port 4.

Next, the liquid crystal injection port 4 of the cell thus formed is
Inject a ferroelectric liquid crystal with a chiral smectic C phase from 12 to 12. At this time, since the liquid crystal injection port 4 is wide and corresponds to one side of the overlapping upper and lower substrates 1.2, even a strong LM liquid crystal having high viscosity can be quickly injected.

When the liquid crystal injection is completed, an inert resin piece 5 is press-fitted into the liquid crystal injection port 4 to close the injection port 4. The inert resin piece 5 may be a soft, plastic synthetic resin that is inactive against liquid crystals such as ferroelectric liquid crystals, such as polytetrafluoroethylene, polychlorotrifluoroethylene, or detrafluoroethylene hexafluoroethylene, which has low surface energy. It is made of fluororesin such as fluoropropylene copolymer, acetal resin, etc., and has a linear or short strip shape. That is, as shown in FIG. 2, 1! of the upper and lower substrates 1.2! The above-mentioned synthetic resin wire, the above-mentioned synthetic resin small piece, etc., which has a diameter and thickness larger than the plate spacing and is strong enough to block the injection port 4, is pressed against the injection port 4, and a part of it is plastically deformed to form the injection port 4. Press it further inside. As a result, most of the liquid crystal injection port 4 is sealed and obstructed by the inert resin piece 5. However, in this state, the substrates 1 and 2 and the inert resin piece 5 are only in mechanical contact, and the bonding surfaces are not chemically bonded, so the inert resin piece 5 may come off. There is sex. For this purpose, a sealing resin liquid 6 made of a photocurable acrylic resin, a silicone resin, or the like is further applied onto the resin piece 5 and cured to perform the resin N1. At this time, as shown in FIG. 2, it is necessary to apply the sealing resin liquid 6 so as to cover all the inert resin pieces 5 and come into contact with the lower substrate 1 and the upper substrate 2.

A polarizing plate and the like are then attached to the liquid crystal self produced in this manner by a conventional method to form a liquid crystal element.

According to the manufacturing method of such a liquid crystal element, since liquid crystal such as ferroelectric liquid crystal is injected through the wide liquid crystal injection port 4,
It can be completed in a short time, and there is no liquid crystal separation or alignment change during liquid crystal injection. Furthermore, since the wide injection port 4 is first sealed with the inert resin piece 5, there is almost no contact between the sealing resin 6 and the liquid crystal, resulting in inconveniences such as the tJJl resin 6 melting into the liquid crystal. This eliminates the problem of liquid crystal alignment near the injection port 4.

Although the above manufacturing method example describes a liquid crystal cell having a wide liquid crystal injection port 4, it is not necessarily applicable only to a liquid crystal cell having a wide liquid crystal injection port 4, but is applicable to a normal liquid crystal cell having a relatively narrow injection port. Of course, it is also possible to do so, and in short, the present invention can be applied to any combination in which there is a possibility that an undesirable reaction between the sealing resin and the liquid crystal may occur.

〔Example〕

A transparent electrode made of indium tin oxide and an alignment film made of polyimide were formed on the surfaces of two glass sheets [1], and the alignment film was subjected to a rubbing treatment.

Alumina powder (IIF (m1-[
(manufactured by Tsugo, rPPs-2, Oj) was sprinkled as a spacer, and as shown in Figure 1, a band of ultraviolet curing resin 10Tscutite 350J (manufactured by Nihon Loctite (■)) was applied to the three sides around the 1j board. and used as a sealant.

After stacking other substrates on this substrate, use an ultraviolet irradiator [
Ultraviolet rays were irradiated for 3 minutes using a mini-t1a UV450J (manufactured by Ushio Denki ■) to harden the sealing material, and the two substrates were joined to form a cell.

The distance between the substrates of the cell thus produced was measured with a Michelson interferometer fMI-flsJ (manufactured by Mizojiri Optical ■) and was found to be 2.2 μm.

Next, from the main entrance of the liquid crystal (liquid crystal without a sealing material in this cell), enter the ferroelectric liquid crystal RCS-1014J (manufactured by Jisso).
was injected. The injection of this liquid crystal was completed quickly. Next, a polytetrafluoroethylene wire (unfired product) with a diameter of 0.5 m was press-fitted into the injection port to close the injection port, and other resins [Lock Tie 1 to 352J] were applied using ultraviolet light from above.
(Nihon Loctite (manufactured by No. 1) was applied, irradiated with ultraviolet rays, and the resin was fixed while avoiding curing, and the liquid crystal cell was placed.

This liquid crystal cell was slowly cooled from the isotropic liquid phase to obtain uniform orientation throughout the cell.

In this liquid crystal cell, there is no alignment unevenness near injection 1-] that has been observed in the past, and no alignment unevenness occurs even after a heat resistance test at 60°C. It did not spread to any area.

〔Effect of the invention〕

As explained above, the method for manufacturing a liquid crystal element of the present invention includes two steps.
3. ! Liquid crystal is injected from the liquid crystal injection port into the gap formed by placing the plates facing each other, and a piece of inviscid resin is press-fitted into this injection [1], and then the resin is sealed. There is almost no direct contact between the resin and the liquid crystal, and there is no possibility of unfavorable interactions between the resin and the liquid crystal. For this reason, even if measures are taken to shorten the injection time of liquid crystals such as ferroelectric liquid crystals and prevent separation of liquid crystals, changes in alignment state, etc. by widening the number of liquid crystals), The contact area between the liquid crystal and the liquid crystal can be made small, and dissolution of the sealing resin into the liquid crystal can be almost completely prevented, thereby making it possible to prevent alignment defects near the liquid crystalline temperature.

[Brief explanation of drawings]

1 and 2 are drawings for explaining the manufacturing method of a liquid crystal element of the present invention, and the first leapfrog is a schematic plan view and the second leapfrog is a schematic plan view.
The figure is a schematic cross-sectional view. 1... F substrate, 2... Upper substrate, 3... Sealing material, 4... Liquid crystal injection port, 5... Inert Resin piece, 6...Resin liquid for sealing. Patent applicant Alps Electric Co., Ltd. Representative Kataoka Katsuabe a f; 171 Figure 1 Figure 2

Claims (2)

[Claims] (1) A liquid crystal element characterized by injecting liquid crystal from a liquid crystal injection port into a gap formed by opposing two substrates, then press-fitting an inert resin piece into the injection port, and then sealing with resin. manufacturing method. (2) The method for manufacturing a liquid crystal element according to claim 1, wherein the liquid crystal is a ferroelectric liquid crystal.