JPH04177324A - Liquid crystal panel and spacer for liquid crystal panel - Google Patents

Abstract

PURPOSE:To reduce bad orientation, in particular at the time of voltage application, in the vicinity of a spacer by using a spacer that has a characteristic of vertical orientation of the surface to a liquid crystal. CONSTITUTION:The orientation condition of a panel which is dispersed in vertical orientation on a spacer surface, is the orientation condition of a spacer 11, of the vicinity of a spacer 12, and of the other part 13, and when the process of vertical orientation is not provided, the orientation condition is for a spacer 61, for the vicinity of the spacer 62, and for the other part 63. A figure (a) indicates the orientation condition where no voltage is applied, and voltages of 2.2V is applied in a figure (b), and 3.0V in a figure (c). When the figure (a) is examined, no difference is shown concerning bad orientation region in the vicinity of the spacer. When the figures (b) and (c) are compared with each other, if the process of vertical orientation is provided, the liquid crystal particle in the vicinity of te spacer is orientated in the same way as the other particle, while if the surface process is not provided, the liquid crystal particle in the vicinity of the spacer is hard to respond to an electric field, and orientation is thus different. The difference in the orientation in the vicinity of spacer is thus reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to optical elements such as display elements and optical shutters, and particularly to liquid crystal panels and spacers for liquid crystal panels.

BACKGROUND ART Conventional techniques will be explained below with reference to the drawings. Liquid crystal panels are currently attracting the most attention for their flatness and light weight.

Currently, demand is increasing for large high-definition displays of about 10 inches in size for computer terminals and word processors as well as small panels for watches, calculators, etc. As the demand for such large-sized displays increases, there is a need for technology for producing liquid crystal panels with a large area and uniform display quality.

The structure of a conventional liquid crystal panel is shown in FIG. In FIG. 2, 21 is an upper and lower glass substrate, 22 is a transparent conductive film layer, 23 is an alignment film layer, 24 is a sealing resin for bonding the upper and lower substrates,
25 is a liquid crystal layer, and 26 is a spacer for adjusting the gap between the upper and lower substrates.

As shown in FIG. 2, a liquid crystal panel uses a gap adjusting material called a spacer to adjust the gap between the upper and lower substrates (cell gap). This spacer is made of inorganic material (
A variety of materials are used, including finely cut glass fibers or silica beads), organic polymer resins (finely cut polybar or silica beads), and organic polymer resins (polystyrene beads). It is being By uniformly distributing these spacers on the substrate, a precise cell gap can be formed. An example of the dispersion method is shown in Figure 3. Third
In the figure, 31 is a spacer, 32 is a spacer stand, 3
3 is a nitrogen jet pipe, 34 is a liquid crystal cell substrate, and 35 is a spacer dispersion box.

First, a predetermined amount of spacers is placed on a stand, and nitrogen is blown out to uniformly disperse the spacers onto the substrate. By bonding the sprayed substrate to the other substrate provided with the sealing resin, a uniform cell gap can be formed even over a large area. By injecting liquid crystal into the blank panel thus created, a uniform liquid crystal panel can be obtained.

Conventional examples of these include Patent Publication No. Sho and Patent Publication No. Sho.

Problems to be Solved by the Invention However, the above-mentioned spacers have the problem of causing alignment defects in liquid crystal panels.

In view of the above problems, an object of the present invention is to obtain a liquid crystal panel and a spacer for a liquid crystal panel.

Means to solve problems The following means were used to solve the above problem.

A space whose surface has the property of vertically aligning liquid crystal molecules.
The orientation disorder is reduced by using a glass plate.

Function: In the present invention, since the spacer surface has vertical alignment, interaction with the liquid crystal is weakened, and alignment disturbance in the vicinity of the spacer can be minimized.

, Example Hereinafter, a liquid crystal panel and a spacer for a liquid crystal panel according to an example of the present invention will be described with reference to the drawings.

A method for manufacturing a liquid crystal panel will be described below.

A glass substrate (1,1 cabinet) containing indium-tin oxide (hereinafter referred to as ITO) was immersed at 50°C for 110 minutes using a weakly alkaline liquid crystal substrate cleaning agent (trade name: Daybosch), and then soaked in pure water. Rinse with running water for about 10 minutes,
Dry in a clean oven at 110°C for 1 hour.

After drying, a 4wt% polyimide/N-methylpyrrolidone solution manufactured by Nichiryo Kagaku Co., Ltd. was coated on the ITO substrate using a spinner, and dried and cured at 200°C for 1 hour to form a film with a thickness of approximately 5.
A membrane of 00 people was set up. Thereafter, an orientation regulating force was applied by a normal rubbing method.

FIG. 4 shows a schematic diagram of the rubbing direction. The twist angle of the liquid crystal was set to 240 degrees. In FIG. 4, 41 is the upper substrate, 42 is the lower substrate, 43 is the rubbing direction of the upper substrate, 4
4 represents the rubbing direction of the lower substrate. A sealing resin was printed on one side of the liquid crystal panel substrate produced as described above by screen printing as shown in FIG. 5. Seal resin is EH
LCB200 manufactured by Company C was used. At this time, add 2 wt% of finely crushed glass fiber (6.0 μm, manufactured by Nippon Electric Glass Co., Ltd.) to the sealing resin (mix it in advance). Represents resin.

Next, a method of imparting vertical alignment to the spacer surface, which is an embodiment of the present invention, will be described. A 6.0 μm microbar manufactured by Tanezu Fine ■ used as a spacer was immersed in a 0.1 wt % ethanol solution of vertical alignment agent Z L 1-3124 manufactured by Merck, and after being taken out, it was air-dried. Other vertical alignment agents such as ZLI3334 manufactured by Merck, 0D manufactured by Chisso
S-E (octadecyltriethoxysilane), DMO
A similar method is used for long-chain alkylsilanes such as AP (N,N-dimethyl-N-octadecyl-3aminopropyl-trimethoxysilyl chloride), hexamethyldisiloxane, hexadecyltrimethoxychloride, and isopropyltrioctanoyl titanate. It was applied to the surface of the spacer.

On the other board, use the method described above to install ZLI31 manufactured by Merck.
Micropearls (diameter 6.0 μm) manufactured by Tanezu Fine ■, which had been surface-treated with 24, were sprayed using the method shown in Figure 3.
The density was set to about 150 pieces/an2. The above two liquid crystal substrates were bonded together and left in a constant temperature bath at 150° C. for 2 hours while applying a pressure of approximately 1 kg/C11l uniformly to effect curing and adhesion. Liquid crystal was injected into the empty panel for liquid crystal produced in this manner by a vacuum injection method. The liquid crystal used was ZLI2293 manufactured by Merck & Co., Ltd. Figure 1(a) shows the alignment state near the spacer of the created liquid crystal panel.
(b) Shown in (C). Figure 1 (a) shows the orientation state with no voltage applied, Figure 1 (b) shows 2.2■, and Figure 1 (C) shows 3
．． A voltage of 0■ is applied. (The pressure waveforms are all 60
A Hz sine wave is used. ) For comparison, the orientation state of the panel sprayed without vertical alignment treatment on the spacer surface is shown in the sixth column.
Shown in Figures (a), (b), and (C). The voltage application was the same as in FIG. Comparing FIG. 1(a) and FIG. 6(a), there is almost no difference in the misaligned region near the spacer. However, in FIG. 1(b) and FIG. 6(b) in which voltage is applied,
Comparing Figure 1 (C) and Figure 6 (C), it was found that in the vertically aligned spacer, the liquid crystal molecules near the spacer were oriented in almost the same way as other molecules, but no surface treatment was applied. In the spacer, the liquid crystal molecules near the spacer were difficult to respond to the electric field and were oriented differently. Although the above results were similar with other vertical alignment agents, the force/sampling agent series seemed to be superior in terms of reliability and reproducibility. In FIG. 1, 11 is a spacer, 1
2 shows the orientation state near the spacer, and 13 shows the orientation state of other parts. Similarly, in FIG. 6, 61 represents the spacer, 62 represents the orientation state near the spacer, and 63 represents the orientation state of other parts.

This result was similar for the 90 degree twist type liquid crystal panel. Similar results were obtained with other spacers, such as glass fibers, silica beads (true thread balls) made by Catalyst Kasei, or Eposter made by Nippon Shokubai Kagaku. Moreover, it is considered that instead of surface-treating the spacer, it is sufficient if the material of the spacer itself has such characteristics.

Further, it is thought that such an effect exists even in ferroelectric liquid crystal, although it is small (because the spacer diameter is small), so it has an effect.

Effects of the Invention The present invention has the effect of reducing alignment defects in the vicinity of the spacer (particularly when voltage is applied) by using a spacer whose surface has the property of aligning perpendicularly to the liquid crystal.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing the orientation of a liquid crystal panel according to an embodiment of the present invention, Fig. 2 is a configuration diagram of the liquid crystal panel, Fig. 3 is an explanatory diagram of the spacer dispersion method, and Fig. 4 is a diagram showing the rubbing direction. FIG. 5 is a schematic diagram showing the shape of the printed seal resin, and FIG. 6 is a schematic diagram showing the orientation of a liquid crystal panel as a comparative example. 11...Spacer, 12...Orientation state near the spacer, 13...Other alignment states. Name of agent: Patent attorney Shigetaka Awano 1 person 112 Figures 4 and 5

Claims (6)

[Claims] (1) A liquid crystal panel in which a pair of substrates are arranged facing each other with a predetermined gap between them by a spacer, and the surface of the spacer arranged inside the cell has a property of aligning perpendicularly to the liquid crystal. (2) The liquid crystal panel according to claim (1), wherein the spacer is surface-treated with a vertical alignment agent. (3) The liquid crystal panel according to claim (2), wherein the vertical alignment agent comprises a coupling agent. (4) A spacer for use in a liquid crystal panel comprising a pair of substrates facing each other, characterized in that the spacer has a property of vertically aligning the liquid crystal in contact with the spacer. (5) The spacer for a liquid crystal panel according to claim (4), wherein the surface is subjected to a vertical alignment treatment. (6) The spacer for a liquid crystal panel according to claim (4), wherein the vertical alignment agent is a coupling agent.