JPS62163018A - Manufacturing method of liquid crystal display device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method of manufacturing a liquid crystal display device, and particularly to a method of manufacturing a substrate surface treatment for orienting a liquid crystal layer.

[Conventional technology]

Conventional alignment treatment methods include inclined vapor deposition of Sin, Au, etc.
JP-A-49-17746) or PVA on the substrate surface.
A method has been proposed in which the resin or polyimide resin is applied in equal amounts and then rubbed in a certain direction with a cotton cloth or the like.

[Problems to be solved by the present invention]

However, although the above-mentioned tilted vapor deposition method is very advantageous in providing a predetermined pretilt angle to the liquid crystal, it has the drawback of requiring large-scale equipment and slowing down productivity. Furthermore, the rubbing method allows the pretilt angle of the liquid crystal to be set freely. In particular, it was difficult to increase the pretilt angle.

The present invention is intended to solve these problems.The purpose of the present invention is to combine only the advantages of conventional methods, and to create a manufacturing method for liquid crystal display devices that is highly productive while providing a free pretilt angle and uniform alignment2. This is what we provide.

[Means to solve the problem]

In the present invention, in the manufacturing process of a liquid crystal display device, a step of rubbing hard powder of a predetermined particle size on the surface of at least one substrate in contact with the liquid crystal from a predetermined angle with a sponge, cloth, etc. The method is characterized in that it includes a step of vertically aligning the substrate.

[Effect]

In other words, the present invention is capable of forming recesses on the surface of a substrate by honing, blasting, or the like, using powder as it is or mixing it with water, air, etc., setting the angle between the nozzle and the substrate at 50 degrees or less, and ejecting the powder at high pressure. Applied to the alignment treatment of liquid crystal display devices, it is possible to set the optimum conditions such as the conditions for the treatment film on the substrate surface, the particle size of the powder, the mixing ratio of powder, water, air, etc., firing pressure, and the angle between the nozzle and the substrate. , set the pre-tilt angle of the liquid crystal to 5
It is possible to obtain a uniform orientation 2 by rubbing the treated substrate. Furthermore, by performing vertical alignment treatment on the treated substrate, it was possible to obtain a pretilt angle of approximately 45° to 85° and uniform alignment.

[Example 1] The present invention will be described in detail below using Examples.

FIG. 1 is a diagram of the invention.

10,001 coats of saliimide resin 3 was applied to a substrate 2 of a liquid crystal display device, which was prepared by patterning a soda glass with a TO material. After this, a mixture of alumina powder with a particle size of 10 μm and water at a ratio of 1:100 (weight ratio) was poured into the nozzle 1 at 51 &
It was fired at a pressure of /cfI. The firing angle is 5° with respect to the board.
The substrate was moved at 30 crn/sec. When holding a liquid crystal with such a substrate and measuring the pretilt angle of the liquid crystal, it was approximately 1
It was 5°. When the above substrate was rubbed to form a twisted nematic liquid crystal display device, a display device having uniform alignment over the entire display surface was obtained.

[Example 2] A mixture of alumina powder with a particle size of 10 μm and water in a ratio of 1=1°O (weight ratio) was fired at a pressure of 5 KP/j onto the soda glass substrate 2 coated with the PVA resin 3. did. The firing angle was 5° relative to the substrate, and the substrate was moving at 3 ocb/sec. When a liquid crystal was held between such substrates and the pretilt angle of the liquid crystal was measured, it was approximately 20'. Further, when rubbing was performed in the same manner as in Example 1 and a liquid crystal display device was constructed, the same results as in Example 1 were obtained.

[Example 3] A mixture of alumina powder with a particle size of 10 μm and water at a ratio of 1=1°O (weight ratio) was 51j/, -,! At a pressure of
．． 3 onto a soda glass substrate 2 sputtered onto ITO. Launch angle is 10' to the substrate, and the substrate is 30 cm.
It moved in 7 seconds. The pretilt angle of the liquid crystal was measured by holding the liquid crystal between the bending substrates and found it to be approximately 15°. Further, rubbing was carried out in the same manner as in Example 1 to construct a liquid crystal display device. [Example 4] Ingropilt soisostearoyl titanate (a titanate coupling agent ), the liquid crystal was sandwiched, and the pretilt angle of the liquid crystal was measured, and it was found to be approximately 75
It was °. When a liquid crystal display device was constructed, a display device with uniform alignment was obtained as in Example 1.

[Example 5] SiO□ powder with a particle size of 5 μm and water were mixed at a ratio of 2:100 (weight ratio), and the body ratio of air to the mixed water was set to be 1:1. The spray was fired at a pressure of 101φ/°- onto a soda glass substrate coated with Nozzle No. 3. The angle between the nozzle and the substrate was 10°, and the substrate moved at a rate of 15tM1/sec.

This substrate was subjected to vertical alignment treatment using the same titanate coupling agent as in Example 4, a liquid crystal was sandwiched therebetween, and the pretilt angle of the liquid crystal was measured and found to be approximately 60°. In addition, when the liquid crystal display device was constructed, the orientation was the same as in Example 1 [effect of the invention]. can be given a high pretilt angle.

It has been found that providing a high pretilt angle to a liquid crystal is very advantageous for display using the birefringence mode of liquid crystals, which has been attracting attention in recent years. Conventionally, in liquid crystal display devices using this birefringence mode, the above-mentioned oblique evaporation method has often been used to obtain a high tilt angle. Liquid crystal display devices using birefringence mode have superior contrast compared to conventional liquid crystal display devices using TN mode, and their mass production is expected from various quarters. This poor quality led to increased costs.

In particular, the present invention is an epoch-making method that dramatically increases the productivity of liquid crystal display devices using the birefringence mode described above, but a new manufacturing method can also be created by applying it to the TN mode as in the embodiment. Ii! of the liquid crystal display device obtained. ! ! This is a very useful method for construction.

[Brief explanation of drawings]

Figure @1 shows a diagram of the present invention. 11-・1・・Nozzle 2... Soda glass substrate 3...Polyimide resin, PVA resin, Sin. Equal surface treatment film that's all Applicant: Seiko Epson Corporation ＜−′

Claims (2)

[Claims] (1) In the manufacturing process of a liquid crystal display device in which a liquid crystal is sandwiched between a pair of substrates, hard powder of a predetermined particle size is applied from a predetermined angle to the surface of at least one of the substrates in contact with the liquid crystal in a certain direction. 1. A method for manufacturing a liquid crystal display device, comprising the step of rubbing. (2) A step of applying a hard powder having a predetermined particle size from a predetermined angle to a surface of at least one of the substrates, which is in contact with the liquid crystal, is subjected to a vertical alignment treatment. A method of manufacturing the liquid crystal display device described above.