JP2624088B2 - Liquid crystal display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display.
In particular, it relates to a liquid crystal display device using a ferroelectric liquid crystal.

[0002]

2. Description of the Related Art Ferroelectric liquid crystals have excellent high-speed responsiveness, have a memory property, and are extremely promising as materials for large-capacity display devices. However, while having these advantages, since the liquid crystal molecules have a layer structure, alignment defects caused by this are listed as one of the serious drawbacks that hinder the commercialization of ferroelectric liquid crystals.

[0003] A ferroelectric liquid crystal display device is provided with an injection hole used to confine liquid crystal in a cell. In particular, the above-mentioned defect of the liquid crystal layer structure is caused by the influence of the shape of the injection hole. This layer structure defect is generally described as being caused by a shift in the inclination of the layer in the cell thickness direction. If a defect occurs, an important monodomain is not formed in the liquid crystal display device. The generated layer structure defect is formed in a direction substantially parallel to the direction of the layer of the liquid crystal sealed in the cell, and the memory property is reduced centering on the defective portion. Therefore, when a layer structure defect in the layer direction penetrates into the display partition, particularly into the display pixel, the adverse effect on uniform appearance and visibility of the entire display device is very large.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to eliminate a layer structure defect in a layer direction due to the influence of an injection hole and to provide good appearance and uniformity. To provide a simple display device.

[0005]

A liquid crystal display device according to the present invention comprises a pair of substrates having electrodes on opposing inner surfaces and a sealing material.
Liquid crystal with memory properties is sandwiched between
Rubbing the surface of the substrate on which the electrodes are formed by rubbing
Orientation treatment is performed, and the injection for injecting the liquid crystal is performed.
In the liquid crystal display device hole is formed in the sealing material, distribution wherein the liquid crystal is layered structure on the inner surface direction of the substrate
And extending from the injection hole in the layer structure.
The layer to be lined is inside the substrate outside the side of the display parting area.
The rubbing direction is set so as to fit on a surface of the liquid crystal display device.

[0006]

FIG. 1 is a view showing one embodiment of a liquid crystal display device of the present invention. Although the layer transition process of the ferroelectric liquid crystal is various, the first embodiment has a cholesteric phase and a smectic A phase in the phase transition process from the isotropic region of the liquid crystal to the chiral smectic C phase where ferroelectricity appears. Using liquid crystal,
A rubbing treatment was performed on the substrate surface to orient the substrate. The cholesteric pitch in the cholesteric phase is 2 μm.
During the phase transition from the cholesteric phase to the smectic A phase, the direction of the liquid crystal layer does not become perpendicular to the rubbing direction and shifts about 10 degrees clockwise when the upper substrate is viewed from the paper side. Created a cell.

A transparent electrode for driving is patterned on the substrate 1 by photo-etching, and a polyimide film for orientation control is 500
Printed with thickness of Å and fired at high temperature to form. A rubbing process was performed on the polyimide film by shifting it 10 degrees counterclockwise as shown by an arrow 6 with respect to the substrate side so that the direction of the layer normal coincides with the parting side 5 of the display device. After patterning the transparent electrode on the lower substrate 2, a polyimide film is formed in the same manner as the substrate 1, but no rubbing treatment is performed.

Next, in order to keep the distance between the upper and lower substrates at 2 μm,
A 2 μm diameter space material is dispersed on the substrate 1 and
After forming a sealing material 3 having three liquid crystal injection holes for sealing liquid crystal between the upper and lower substrates by a printing method, the two substrates are bonded to each other. After the curing of the sealant was completed, the liquid crystal was injected into the vacuum container. After the injection was completed, the cell was sealed with the encapsulant 4.

FIG. 2 shows another embodiment of the present invention, which is a display device in which an injection hole 8 'is provided at a cell end. The liquid crystal is made of the same material as in the first embodiment, and the rubbing direction is not perpendicular to the liquid crystal layer direction. A rubbing process is performed in a direction parallel to the side 5 '(arrow 6') on the polyimide film formed on the upper substrate 1 ', and the lower substrate 2' is formed only with an indium oxide film as a transparent electrode. The space agent for maintaining the space between the upper and lower substrates was dispersed, the sealant 3 'was formed by printing, and after bonding the upper and lower substrates, the liquid crystal was sealed.

[0010]

As described above, according to the present invention, the rubbing direction is calculated from the following formula (1) from the relationship between the direction of the liquid crystal layer formed in the liquid crystal display device and the parting-off area, and the display device is formed. Structural defects caused by the injection holes do not enter the display parting area, and a display with uniform display performance in the parting and no defect can be obtained. It is a great place to contribute to.

Φ <tan ⁻¹ (X / Y) −θ φ: angle between parting side 5 and rubbing direction θ: angle between rubbing direction and layer normal direction X: injection hole and parting Distance from side 9 Y: distance between injection hole and parting side 5

[Brief description of the drawings]

FIG. 1 is a diagram showing one embodiment of a liquid crystal display device using a ferroelectric liquid crystal of the present invention.

FIG. 2 is a diagram showing another embodiment of the liquid crystal display device using the ferroelectric liquid crystal of the present invention.

FIG. 3 is a diagram showing a rubbing direction calculation direction.

[Explanation of symbols]

 1, 1 ': Upper substrate 2, 2': Lower substrate 3, 3 ': Sealing agent 4, 4': Sealing agent 5, 5 ': Display device 6, 6, '・ ・ ・ Rubbing direction 7 ・ ・ ・ Defect of liquid crystal layer structure 8 ・ ・ ・ Injection hole 9 ・ ・ ・ Partition of display device 10 ・ ・ ・ Direction of liquid crystal layer

Claims (1)

(57) [Claims] A pair of substrates having electrodes on inner surfaces facing each other;
Liquid crystal with memory properties is sandwiched between the sealing material
Rubbing on the surface of the substrate on which the electrodes are formed
And the liquid crystal is injected.
In the injection hole the liquid crystal display device in which are formed in the sealing material because the liquid crystal is arranged in a layer structure on the inner surface direction of the substrate
And extending from the injection hole in the layer structure.
Layer on the inner surface of the substrate outside the side of the display parting area
A liquid crystal display device , wherein the rubbing direction is set so as to fit .