JPS58149022A - Production of liquid crystal display substrate - Google Patents

Abstract

PURPOSE:To eliminate washing of substrates by peforming rubbing of orientation control films while said films are exposed to washing atmospheres of liquid or gas during the work thereby removing the contaminating sources, such as fibers, stripped from rubbing rolls successively and preventing the sticking of the contaminants. CONSTITUTION:Plural pieces of rubbing rolls 3, 3... are disposed in a rubbing section A according to need in the moving diretion of electrode substrates 1. The fibers tufted on the surfaces of the rolls 3 rub the surfaces of orientation control films as the rolls revolve and the substrates 1 are fed forcibly. Nozzles 4 are installed on the same side as the rolls 3 in the passage for the substrates 1 in the section A, and at least one nozzle 4' is installed in the outlet part in the section A where the rubbing ends. The nozzles 4, 4' are disposed in proximity to the rolls 3, and water or liquid or gas of an org. solvent 5 or the like is injected from the nozzles 4, 4' toward the substrates 1, whereby the substrate surfaces are washed in the showering atmospheres. The substrates 1 rubbed in the atmospheres injected with the liquid are fed into a drying section B.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a liquid crystal display substrate, and more particularly to a rubbing treatment of an alignment control film that provides an initial alignment state of liquid crystal molecules.

A liquid crystal display device f, particularly a device constructed using a TN-FEM liquid crystal composition, is equipped with means for directing the initial alignment of liquid crystal molecules filled between opposing electrode substrates. That is, an insulating film made of an organic polymer material such as polyimide or an inorganic material such as 5i02 is uniformly coated as an orientation control film on the surface of an electrode substrate made of a glass plate, plastic film, etc. on which a transparent electrode is formed, and the orientation control film is By flocking the surface and rubbing it with an a-ra etc., the direction in which the liquid crystal molecules are arranged is determined.

The roller conventionally used for the above-mentioned rubbing process has a cylindrical surface VC11 made of fine fibers such as nylon or cotton.
Therefore, during the rubbing process, the fibers not only peel off from the rollers and remain on the electrode substrate, but also the peeled fibers float in the air and adhere to the surface of the electrode substrate being transported. , which was a major cause of pollution.

The present invention provides a method for manufacturing a liquid crystal display substrate, which eliminates the drawbacks of the conventional manufacturing methods described above and allows efficient production of electrode substrates.

Generally, after the rubbing treatment, the glass substrate is washed with water, an organic solvent, etc. to remove contaminants such as fibers. When rubbing the alignment control film, the present invention prevents the adhesion of fibers that have fallen off from the rubbing roller and contamination due to other deposits by working in a cleaning atmosphere, and at the same time eliminates or reduces the need for subsequent cleaning. do.

FIG. 1 shows an outline of a rubbing apparatus for carrying out the present invention, and an electrode substrate 1 coated with an alignment control film is
It is placed on the conveyor 2 and sent to the rubbing section A and the drying section B in sequence. The rubbing part A includes a plurality of rubbing rollers 3, 3, . . . as required in the contacting direction of the electrode substrate 1.
is located.

The fibers flocked on the surface of the rubbing roller 30 rub against the orientation control film surface by rotation of the roller and forced feeding of the electrode substrate 1. In the rubbing part A, a nozzle 4 is installed on the same side as the rubbing roller 3 with respect to the path of the electrode substrate l,
At least one nozzle 4' is installed at the exit of the rubbing section A after the rubbing process. The nozzles 4.4' are arranged close to the rubbing roller 1, and a liquid or gas such as water or an organic solvent 5 is injected from each nozzle 4.4' toward the electrode substrate 1 in a Java atmosphere. The substrate surface is dried and used for assembling a liquid crystal display cell.

FIG. 2 shows another embodiment according to the invention, in which the rubbing process is carried out in a liquid immersion atmosphere. In the figure, an electrode substrate I coated with an alignment control film is placed on a conveyor 12 and forcibly conveyed as in the previous embodiment. A portion of the passage of the conveyor 12 is arranged so as to pass through a tank 15 into which a cleaning liquid such as water or an organic solvent is poured.

A rubbing operation is performed inside the cleaning liquid tank I5 at a position where the orientation control film surface of the electrode substrate 1, which is moved by the conveyor 12, can be rubbed in an atmosphere exposed to the cleaning liquid. It is desirable to stir the cleaning liquid in order to increase its effectiveness, and for example, an ultrasonic generating vibrator 16 is attached.

The electrode substrate 1 that has been rubbed and cleaned by moving through the cleaning liquid tank 15 is pulled up from the tank, sent to the drying section i and dried, and becomes a final electrode substrate constituting a liquid crystal cell.

As described above, according to the present invention, since the rubbing work is performed with the alignment control film exposed to a cleaning atmosphere of liquid or gas during the work, contamination sources such as fibers that have fallen off from the rubbing roller are successively removed, and the contaminants that have broken off are removed. Furthermore, the cleaning of the substrate, which was conventionally performed after the rubbing treatment, can be omitted, and the manufacturing of the electrode substrate becomes extremely efficient.

[Brief explanation of the drawing]

FIG. 1 is a side view of an apparatus used in one embodiment of the invention, and FIG. 2 is a side view of an apparatus used in another embodiment of the invention. Electrode substrate, 8.18 Nilapin roller, 4.4':
nozzle, 5. +5: Cleaning liquid, 13. &: Drying section, 16
: Ultrasonic generation transducer.

Claims (1)

[Claims] l Coating an alignment control film made of an organic polymer material or no material on the substrate on which the electrode conductor is formed, and rubbing the surface of the alignment control film to provide orientation for regulating the alignment of liquid crystal molecules. A method for manufacturing a liquid crystal display substrate, characterized in that a rubbing treatment is performed while the surface of the alignment control film is exposed to a cleaning atmosphere.