JP2595068B2 - LCD rubbing device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a rubbing device for an alignment film used in a liquid crystal display device.

[Prior Art] FIG. 3 is a cross-sectional view showing a conventional rubbing device for a liquid crystal display element, and FIG. 4 is a partially enlarged view for explaining the problem. There is a manual rubbing machine.

In the figure, 1 is a transparent insulating substrate, 2 and 3 are electrodes and an alignment film adhered on the transparent insulating substrate 1,
Denotes a stage for fixing the transparent insulating substrate 1;
Is a rubbing cloth for performing a rubbing treatment, 6 is a roller around which the rubbing cloth 5 is wound, and 9 is air.

 Next, a rubbing method will be described.

First, the height of the roller 6 is adjusted so that the rubbing cloth 5 comes into contact with the alignment film 3 with an appropriate pressure. Next, roller 6
Is rotated, the stage 4 on which the transparent insulating substrate 1 is fixed is moved in the horizontal direction. When the stage 4 moves, a rubbing process is performed by rubbing the alignment film 3 with the rubbing cloth 5. During the rubbing treatment, the surfaces of the rubbing cloth 6 and the alignment film 3 are positively and negatively charged due to frictional charging at a moment when they are separated by a minute distance, and a and b
A potential difference Vab occurs between them. For example, the size of this Vab is 3KV
It is about. Further, a capacitance is formed between the alignment film 3 and the electrode 2 (between b and c), and eventually a potential difference Vac is also generated between the rubbing cloth 5 and the electrode 2 (between a and c) due to capacitive coupling. a,
Vac is almost equal to Vab because the capacitance formed between b (air is dielectric) is much smaller than the capacitance formed between b and c.
be equivalent to.

[Problems to be solved by the invention]

In the conventional method of performing rubbing treatment in air, the potential difference Vab generated between a and b due to frictional charging becomes larger than the dielectric strength of the air existing between a and ab.
Discharge occurs between the electrode and the electrode 2 (between a and c). When this discharge occurs, a large current flows, so that the alignment film 3 and the electrode 2 are damaged, which is one of the important factors for lowering the yield of the liquid crystal display device.

The present invention has been made to solve the above problems, and has as its object to provide a liquid crystal display element rubbing device capable of performing a rubbing treatment without preventing electrostatic discharge and causing damage to an alignment film and electrodes. And

[Means for solving the problem]

The rubbing device for a liquid crystal display device according to the present invention is provided with a means for generating an atmosphere of an electrically negative gas containing halogen in the vicinity of a contact portion between the alignment film and the rubbing cloth.

[Action]

In the present invention, since the electric negative gas containing halogen has a higher dielectric strength than air, the discharge between the rubbing cloth and the electrode is suppressed, and therefore, the rubbing treatment is performed without damaging the alignment film and the electrode. Can be.

〔Example〕

 Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing a rubbing device for a liquid crystal display device according to one embodiment of the present invention. In the figure, 1 is a transparent insulating substrate, 2 and 3 are electrodes and an alignment film adhered thereon, 4 is a stage for fixing the transparent insulating substrate 1,
Reference numeral 5 denotes a rubbing cloth for performing a rubbing treatment, 6 denotes a stage around which the rubbing cloth 5 is wound, and 7 denotes a generator for generating an electric negative gas atmosphere. In this embodiment, the generator is hermetically sealed. Container is used. Reference numeral 8 denotes an electrically negative gas filled with the generator 7 (a gas containing a halogen element and easily attaching electrons to become negative ions).
In this embodiment, SF6 is used.

In the present invention, during the rubbing treatment, a high voltage is generated between the rubbing cloth 5 and the alignment film 3 due to frictional charging, that is, between the rubbing cloth 5 and the electrode. It is much smaller than the dielectric strength of SF6. Therefore, the rubbing treatment can be performed without causing a discharge between the rubbing cloth 5 and the electrode 2, that is, without damaging the alignment film 3 and the electrode 2.

As an example of the SF6 gas pressure in the above embodiment, 3 atm is appropriate, and the dielectric strength at this time is about 2.7 times that of air.

In the above embodiment, the generator 7 in an electrically negative gas atmosphere is used.
Although a closed container surrounding the whole was used as the above, a nozzle as shown in FIG. 2 may be used instead of this container, and in this case, it is difficult to set an appropriate gas flow rate,
The same effect can be obtained by injecting the electric negative gas 8 toward the vicinity of the contact portion between the rubbing cloth 5 and the alignment film 3.

In the above embodiment, SF6 was used as the electrically negative gas 8, but the same electrically negative gas, C6, was used instead of SF6.
A freon gas such as FC12 (F-12) may be used, and the same effect can be obtained.

〔The invention's effect〕

As described above, according to the present invention, the rubbing treatment is performed in a state where the vicinity of the contact portion between the rubbing cloth and the alignment film is in an electrically negative gas atmosphere containing halogen. Discharge caused by frictional charging with the alignment film can be suppressed, and it has a remarkable effect on improving the yield of the liquid crystal display device.

[Brief description of the drawings]

FIG. 1 is a sectional view of a liquid crystal display device rubbing device according to one embodiment of the present invention, FIG. 2 is a sectional view of a liquid crystal display device rubbing device according to another embodiment of the present invention, and FIG. 3 is a conventional liquid crystal display device. FIG. 4 is a sectional view showing a rubbing device, and FIG. 4 is a partially enlarged view for explaining a problem of the conventional device. In the figure, 1 is a transparent insulating substrate, 2 and 3 are electrodes and alignment films adhered on the transparent insulating substrate 1, 4 is a stage for fixing the transparent insulating substrate 1, and 5 is a rubbing process. , A roller for wrapping the rubbing cloth 5, a generator 7 for generating an electric negative gas atmosphere, an electric negative gas 8,
9 is air. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

(57) [Claims] 1. A stage for fixing a transparent insulating substrate having at least one or more electrodes and an alignment film for aligning a liquid crystal on a surface thereof, and a rubbing cloth for rubbing around the periphery. A rubbing device for a liquid crystal display device, comprising: a roller; and a gas atmosphere generating means for generating an electrically negative gas atmosphere containing halogen in the vicinity of a contact portion between the alignment film and the rubbing cloth.