KR19990010129A - Alignment film forming apparatus of liquid crystal display device - Google Patents

Abstract

The present invention relates to an alignment film forming apparatus of a liquid crystal display device, comprising: alignment film printing means for forming an alignment film; A glass substrate on which an alignment film is formed at a position set by the operation of the alignment film printing means; It moves along the set path, the glass substrate is placed and a heater capable of heating the glass substrate is built-in, as the alignment film is formed on the glass substrate by the alignment film printing means as it passes through the alignment film printing means, Including a table for evaporating moisture, the effect of improving the image quality of the liquid crystal display by suppressing the generation of micro pinholes by the leveling operation of the alignment film is generated.

Description

Alignment film forming apparatus of liquid crystal display device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alignment film forming apparatus of a liquid crystal display, and more particularly, to reducing the occurrence of micro pinholes in forming an alignment film using a polyimide liquid for manufacturing a liquid crystal display. It relates to an alignment film forming apparatus of a liquid crystal display device for.

As the size of the liquid crystal display increases, the screen becomes larger, and the precision increases, thereby realizing high quality images.

Therefore, since a large screen of high quality can be realized, the demand for a liquid crystal display device is rapidly increasing and the quality of the liquid crystal panel is important. Therefore, both aspects can be satisfied in consideration of the aspect of improving the quality of the liquid crystal panel and the mass production in the future. Development of manufacturing techniques is required.

However, in the liquid crystal alignment film application process in which the organic polymer film is applied to align the liquid crystal molecules on the transparent conductive film, a leveling operation of evaporating a certain amount of moisture contained in the coated alignment film to evenly coat the coated alignment film after polyimide coating. Depending on the state, small polyimide bubbles, that is, micro pinholes, are generated.

Referring to FIGS. 1A to 1D, a process of generating micro pinholes in forming a conventional alignment layer will be described.

As shown in Fig. 1A, a doctor roll 20 and anilox in which the polyimide liquid is rotating from the upper dispenser 10, which is the alignment film printing unit 100, are shown. The gap between the rolls 30 is held in the state of the thin film on the anilox roll 30.

As described above, in the state in which the polyimide liquid is maintained in the thin film state on the anilox roll 30, the plate copper 40 to which the APR plate (Asahikasei Photosensitive Resin plate), which is the resin plate 41 on which the plate making 42 is formed, is attached. When the rotation is performed, the polyimide liquid is transferred to the plate making 42 on the plate, and when the glass substrate 50 fixed on the table 60 passes under the judgment 40, the coating liquid is printed and the coating liquid of FIG. As shown in b), the alignment layer 70, which is a polyimide film, is formed on the glass substrate 50.

However, in FIG. 1B, when the coating liquid is transferred onto the glass substrate 50 to carry out the polyimide coating operation, small micro pinholes are generated, and the small micro pinholes grow as shown in FIG. 1C. do.

In the end, the micro pinholes are applied in a portion where micro pinholes are generated by bursting during the leveling operation for evaporating the moisture of the coated alignment layer 70 by a predetermined amount using the operation of a plurality of pre-bake devices. Differences occur so that the areas with different pretilts are scattered.

The reason why the micro pinholes are generated during the formation of the alignment layer as described above is that as the number of times of polyimide usage increases, the holes formed in the resin plate and the respective roll portions are not cleaned cleanly, and thus the residue of the polyimide This remains and micro pinholes are formed as described above by incomplete leveling that is not flat when the alignment layer is coated.

And another reason is that the polyimide material itself is used to generate micro pinholes uniquely in the characteristic when coating the alignment film.

Therefore, when the alignment layer is formed as described above, the micro pinholes generated due to the above-described reasons may be black in the areas where the micro pinholes are formed during the gross test for testing the electrical characteristics of the liquid crystal display. Black spots occur and appear gray on the white screen, resulting in poor display.

In order to suppress the occurrence of micro pinholes that increase the defective rate as described above, the delay time after polyimide printing, that is, in the wet zone containing a lot of moisture formed in the alignment film, should be reduced to about 5 seconds as much as possible. After coating, the leveling operation of evaporating the water contained in the alignment film by the set amount must be performed immediately.

However, in the conventional leveling operation, four pre-baking apparatuses for dividing the alignment layer coated on the glass substrate 50 into about four regions and then performing the leveling operation for each set region are mounted.

Therefore, when the four pre-baking apparatuses are sequentially passed, the infrared film and the hot plate are used to perform the evaporation of moisture at each set temperature and burn out the impurity ionic materials, so that the leveling operation of the alignment layer is performed sequentially. .

Therefore, since only the method of replacing or cleaning the resin plate is the only solution in the related art, it causes a huge economic loss due to the cost increase and the delay of the operation of the resin plate at any time.

In addition, since the pre-baking device requires as many separate areas for the leveling operation of each of the alignment layers, a complicated work structure is caused, and the contamination of the panel occurs due to the pre-baking operation, thereby degrading the quality of the liquid crystal panel. Occurred.

In addition, since the leveling operation is not performed at the same time but sequentially, the micro pinhole is formed until the leveling operation is performed, thereby deteriorating the image quality of the liquid crystal display.

Therefore, an object of the present invention is to solve the above-mentioned conventional problems, and relates to an alignment film forming apparatus of a liquid crystal display device for improving the quality of a liquid crystal panel by reducing the generation of micro pinholes when forming an alignment film on a glass substrate.

1A to 1D illustrate a process of forming an alignment layer of a conventional liquid crystal display device.

2 is a block diagram of an alignment film forming apparatus of a liquid crystal display according to an embodiment of the present invention.

The configuration of the present invention for achieving the above object,

Alignment film printing means for forming an alignment film;

A glass substrate on which an alignment film is formed at a position set by the operation of the alignment film printing means;

It moves along the set path, the glass substrate is placed and a heater capable of heating the glass substrate is built-in, as the alignment film is formed on the glass substrate by the alignment film printing means as it passes through the alignment film printing means, It includes a table to evaporate moisture.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Parts having similar configurations to the prior art and executing the same functions are given the same codes as the prior art.

2 is a block diagram of an alignment film forming apparatus of a liquid crystal display according to an embodiment of the present invention.

Referring to FIG. 2, the configuration of the present invention is described with the mounting portion 1 for mounting the glass substrate 50 for mounting the alignment layer on the table 600 and the mounting portion 1 on the table 600. The alignment unit 2 for aligning the position of the glass substrate 50 placed thereon, the alignment film printing unit 100 for forming an alignment layer on the glass substrate 50 placed on the table 600, and the glass substrate on which the alignment layer is formed ( It consists of a transfer part 3 for moving the 50 to the corresponding position on the table 600.

The table 600 is equipped with a heater consisting of a heating coil 601, it is possible to raise the temperature of the table 600 to a desired temperature.

The alignment layer printing unit 100 is engaged with the doctor roll 20 and the dispenser 10 for injecting the polyimide solution, the rotating doctor roll 20, and the doctor roll 20 to rotate in engagement with the doctor roll 20. The anilox roll 30 and the resin plate 41 in which the plate-making 42 is formed are attached, and it consists of the plate 40 which rotates in engagement with the said anilox roll 30. As shown in FIG.

The operation of the present invention consisting of the above configuration is as follows.

First, in order to align the liquid crystal on the glass substrate 50 by the operation of the mounting portion 1, the table 600 is sequentially moved along a designed rail or the like and passes through the mounting portion 1. The glass substrate 50 is positioned on the table 600 by the operation of the mounting portion 1 by the operation of (1).

The alignment layer may be formed at the correct position of the glass substrate 50 by aligning the position of the glass substrate 50 placed on the table 600 to the correct position while passing through the alignment unit 2. To help.

By the dispenser 10 of the alignment film printing unit 100 while passing the alignment film printing unit 100 while the glass substrate 50 is placed on the table 600 in which the heater is built by the operation of the mounting unit 1. As the polyimide solution is injected, the doctor roll 20 and the anilox roll 30 rotate, and the polyimide liquid is applied onto the glass substrate 50 in accordance with the rotation operation of the plate 40 to form an alignment layer.

At this time, the temperature of the table 600 can be adjusted by the operation of the control device not shown by the built-in heater using the heating coil 601.

Therefore, when the alignment film made of polyimide liquid is formed on the glass substrate 50 by the operation of the alignment film printing unit 100, the table 600 is already heated by the operation of the heater built in the table 600. Therefore, the moisture of the alignment layer is rapidly evaporated to perform a quick leveling operation.

At this time, since the temperature of the glass substrate 50 already placed on the table 600 from the alignment unit 2 is preheated to about 60 to 70 ° C. to prevent damage to the glass substrate 50 due to a sudden temperature difference. do.

As described above, as soon as the alignment layer is formed on the glass substrate 50 by the operation of the alignment layer printing unit 100, a leveling operation of evaporating moisture to bake the alignment layer is performed, thereby suppressing the generation of the bubble micro pinhole, and if the alignment layer Even when the micro pinhole is already formed at the time of formation, the growth operation of the micro pinhole is stopped, so that the image quality of the liquid crystal display may be significantly improved.

In addition, since the leveling operation is performed at one time without the need for a plurality of prebaking devices for leveling after forming the alignment layer, it is possible to reduce the cost or waste of space for mounting the prebaking device, and to quickly level the micro The occurrence of pinholes can be significantly suppressed.

When the alignment layer is formed to align the liquid crystal, micro pinholes are suppressed by the rapid leveling operation, and further micro pin growth is stopped, thereby improving the image quality of the liquid crystal display and reducing the defective rate.

In addition, since a separate device for the leveling operation of the alignment layer is not required, it is possible to realize efficient use of manufacturing cost, manufacturing time, and space, thereby achieving significant cost reduction.

Moreover, since it is not necessary to replace or wash the resin plate made manually in order to suppress the formation of the micro pinholes, it is possible to realize a lot of manpower consumption and cost reduction.

Claims (3)

Alignment film printing means for forming an alignment film; A glass substrate on which an alignment film is formed at a position set by the operation of the alignment film printing means; It moves along the set path, the glass substrate is placed and a heater capable of heating the glass substrate is built-in, as the alignment film is formed on the glass substrate by the alignment film printing means as it passes through the alignment film printing means, An alignment film forming apparatus for a liquid crystal display device, comprising a table for evaporating moisture. The method of claim 1, The glass substrate is already preheated to a set temperature before passing through the alignment film printing means, wherein the alignment film forming apparatus of the liquid crystal display device. The method of claim 1, The heater uses a heating coil, the alignment film forming apparatus of the liquid crystal display device.