JPH07261179A - Apparatus for production of liquid crystal display element - Google Patents

Abstract

PURPOSE:To produce a liquid crystal display element having a good display grade free from the defects of oriented film by preventing the destruction of the oriented film by static electricity during a rubbing treatment stage. CONSTITUTION:A rubber mat 4 formed by finely cutting anticharge dielectric fibers and mixing these fibers with a rubber member is directly wound around the cylindrical part of a metallic revolving drum 2, and a rubbing cloth is wound thereon. This revolving drum 2 is rotated at a prescribed speed in the arrow B direction by revolving shafts 3a, 3b and a glass subsrate 7 to be subjected to a rubbing treatment is placed on a moving stage 6 and is horizontally moved in this state in the arrow A direction, by there the oriented film is rubbed while rubbing cloth 5 rubs the oriented film in the specified direction. The rubbing cloth 5 in rubbing is positively electrostatically charged by friction of the oriented film of the glass substrate 7 and the rubbing cloth 5. The negative charges of the opposite polarity are generated in an equal quantity in the rubber mat 4 mixed with the anticharge dielectric fibers under the rubbing cloth 5 to neutralize the charges of the rubbing cloth 5.

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 element manufacturing apparatus, and more particularly to a liquid crystal display element manufacturing apparatus for rubbing an alignment film provided in a liquid crystal cell.

[0002]

2. Description of the Related Art Liquid crystal display devices (LCD: Liquid Crystal)
There is a rubbing device for rubbing an alignment film formed on the surface of a transparent substrate of a liquid crystal cell as a liquid crystal display device manufacturing device for manufacturing a display.

When the alignment film of the liquid crystal display device is subjected to the alignment treatment, the horizontal alignment treatment, the vertical alignment treatment and the tilt alignment treatment are appropriately selected or two or more treatment methods are selected depending on the liquid crystal material and the display mode. Are combined.

In the horizontal alignment treatment of the above-mentioned treatment methods, the liquid crystal molecules are aligned in a predetermined direction only by aligning the liquid crystal molecules with the substrate simply by coating the substrate with the aligning agent. I can't. Therefore, a rubbing treatment step is required in which the surface of the alignment film is rubbed in a certain direction so that the liquid crystal molecules are aligned so that the major axis direction of the liquid crystal molecules is along the rubbing direction.

This rubbing treatment is performed with gauze, felt,
A rubbing cloth such as rubber or brush is used to rub the surface of the alignment film such as polyimide resin in a certain direction. After such a rubbing process, for example, a nematic liquid crystal is injected into the liquid crystal cell so that liquid crystal molecules near the alignment film are aligned along the rubbing direction.

[0006]

In the conventional liquid crystal display device manufacturing apparatus as described above, when rubbing treatment is performed, the glass which is placed on the moving table in a state in which the rubbing cloth is directly wound around the metallic rotary drum is used. The surface of the alignment film on the substrate was rubbed. As a result, normally, the alignment film on the substrate is negatively charged, and the rubbing cloth is positively charged. The electric charge is about several Kv to several tens of Kv, though it varies depending on the rubbing strength and the type of rubbing cloth. For this reason, the charged rubbing cloth may cause an air discharge (spark) and strike a lightning strike on the alignment film when the rotating drum makes one revolution and approaches the alignment film again. A lightning strike generated on the alignment film may destroy the alignment film to form pores of several μm. And in the part where this alignment film is destroyed,
There is a problem that alignment defects of liquid crystal molecules occur and display defects such as display unevenness occur.

Further, in the rubbing process, since the moving table on which the substrate is placed and conveyed is sequentially moved and the rubbing process is performed from the end face, a potential difference is generated between the rubbed portion and the unrubbed portion. As a result, discharge may occur between the transparent electrodes having low electric resistance. In the case of this discharge, the alignment film on the electrodes is also modified in the same manner as described above, resulting in poor alignment of the liquid crystal.

The present invention has been made in view of the above problems, and prevents the alignment film from being destroyed by static electricity during the rubbing process in the manufacturing process of a liquid crystal display element, and thus has no defective alignment film of the liquid crystal and has a good display quality. An object of the present invention is to provide a liquid crystal display element manufacturing apparatus capable of manufacturing a good liquid crystal display element.

[0009]

The invention according to claim 1 is
What is claimed is: 1. A liquid crystal display device manufacturing apparatus for rubbing an alignment film, which regulates the alignment direction of liquid crystal molecules filled in a liquid crystal cell, by rubbing a rubbing cloth, wherein an anti-charge dielectric fiber is present in or near the rubbing cloth. By the provision of, the above-mentioned object is achieved.

According to a second aspect of the present invention, the anti-charge dielectric fibers are mixed in a mat-like rubber member and laid under the rubbing cloth to achieve the above object.

According to a third aspect of the present invention, the anti-charge dielectric fiber is woven into the base cloth portion of the rubbing cloth to achieve the above object.

According to a fourth aspect of the present invention, the rubbing cloth is provided on a peripheral surface of a metallic rotating drum, and the rotating drum is rotated to rub the alignment film in a predetermined direction.
To achieve the above objectives.

[0013]

According to the first aspect of the invention, the anti-charge dielectric fiber is provided in or near the rubbing cloth which is rubbed by rubbing the alignment film.

The anti-charge dielectric fiber has a characteristic that an electric charge having a polarity opposite to that of the electric charge is induced by an electric charge existing in the vicinity. Therefore, the charge on the rubbing cloth is
Since the charge is opposite to that of the rubbing cloth generated in the anti-charge dielectric fiber and is neutralized by an equal amount of electric charge, the potential difference between the rubbing cloth and the alignment film on the substrate does not become large, so the discharge does not occur. It does not occur, and the alignment film can be prevented from discharge breakdown.

According to the second aspect of the invention, the anti-charge dielectric fiber is mixed in the mat-shaped rubber member, and the rubber member is laid under the rubbing cloth.

Therefore, the electric charge charged on the rubbing cloth causes the anti-charge dielectric fibers in the mat-like rubber member laid under the rubbing cloth to generate an equal amount of electric charges of opposite polarity, thereby electrically. Since it is neutralized, it is possible to prevent the alignment film from being destroyed by discharge.

According to the third aspect of the invention, the anti-charge dielectric fiber is woven into the base cloth portion of the rubbing cloth.

Therefore, the electric charge charged on the rubbing cloth causes the anti-charge dielectric fibers woven in the base cloth portion of the rubbing cloth to generate an equal amount of electric charges with opposite polarities, and thereby electrically neutralize. The alignment film can be prevented from being destroyed by discharge.

In the invention according to claim 4, the inventions according to claims 1 to 3
The rubbing cloth described in any one of 1 to 3 above is attached to a metallic rotating drum, and while the rotating drum is rotated, the alignment film coated on the substrate is rubbed in a certain direction to perform the alignment treatment.

Therefore, the rubbing process can be efficiently performed by simply rubbing the alignment film while rotating the rotary drum to which the rubbing cloth is attached in the alignment direction, and the charged portion of the rubbing cloth makes one rotation to form the alignment film again. Since the rubbing cloth charged by the charge induced in the anti-charge dielectric fiber is electrically neutralized during the contact, the alignment film can be protected from discharge breakdown.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 3 are views for explaining the construction of an embodiment of a rubbing apparatus which is a liquid crystal display element manufacturing apparatus of the present invention.

First, the structure will be described.

FIG. 1 is a plan view of the rubbing apparatus 1.

In FIG. 1, the rubbing device 1 comprises a rotary drum 2, rotary shafts 3a and 3b, a rubber mat 4, a rubbing cloth 5, and a moving stage 6.

In the rubbing device 1, a special rubber mat 4 is wound around the peripheral surface of the metallic rotating drum 2, and a rubbing cloth 5 for rubbing treatment is wound around the special rubber mat 4.

The rubber mat 4 is obtained by finely cutting the anti-charge dielectric fiber, mixing it with rubber, and molding it into a mat. The anti-charge dielectric fiber used in this example produces an equal amount of electric charge having the opposite polarity to the electric charge of the charged object by bringing the anti-charge dielectric fiber close to or in contact with the surface of the object charged by friction or the like. It is a thing. The charge generated on the anti-charge dielectric fiber neutralizes the charge of the charged object. As the anti-charge dielectric fiber, for example, SOLDION (manufactured by Toray Group Shiga Shusan Co., Ltd.), which is a static electricity removing fiber, was used, but the anti-charge dielectric fiber is not limited to this and may be any one having the above physical properties. .

As the rubbing cloth 5 attached to the rubber mat 4 described above, generally used raised gauze, felt, rubber, brush or the like can be preferably used.

The moving stage 6 is a substrate carrier that moves in a horizontal direction (in the direction of arrow A in FIG. 1) with the glass substrate 7 placed thereon.

The glass substrate 7 is a substrate that constitutes a liquid crystal cell of a liquid crystal display panel, and ITO (Indium) is formed on the surface of the substrate.
Tin Oxide: Indium tin oxide) or the like is formed with a transparent electrode in a predetermined pattern, and an alignment film is applied and formed thereon by a spin coating method or the like. The rubbing cloth is placed on the moving stage 6 and rotates. 5 is conveyed below so as to rub against it and subjected to a rubbing process.

Next, a rubbing process operation by the rubbing device will be described.

As shown in FIG. 1, a rubber mat 4 obtained by finely cutting anti-charge dielectric fibers and mixing them with a rubber member is directly wound around a cylindrical portion of a metal rotary drum 2, and a rubbing cloth is rubbed on the rubber mat 4. 5 is wrapped around.

When the rubbing process is performed, the rotary drum 2 is rotated at a predetermined speed in the arrow B direction by the rotary shafts 3a and 3b. Glass substrate 7 to be rubbed
Is placed on the moving stage 6, horizontally moved in the direction of arrow A, and rubbed against the rubbing cloth 5 to perform rubbing. That is, the alignment film on the glass substrate 7 is rubbed by rubbing the rubbing cloth 5 rotating in the direction of the arrow B sequentially from the front end surface of the glass substrate 7 in the traveling direction A.

The rubbing cloth 5 that has been rubbed as described above is, for example, positively charged by the friction between the alignment film of the glass substrate 7 and the rubbing cloth 5. However, in the rubbing apparatus of this embodiment, the rubber mat 4 in which the anti-charge dielectric fiber is mixed is laid under the rubbing cloth 5, so that the contact surface between the rubbing cloth 5 and the rubber mat 4 is immediately opposite in polarity. An equal amount of negative charge is generated, and the charge on the rubbing cloth 5 is neutralized. As a result, even if the rubbing cloth 5 makes one rotation and approaches the alignment film again, the electric potential difference between the rubbing cloth 5 and the alignment film is small, so that no discharge occurs between the rubbing cloth and the alignment film. Further, since the accumulation of charges on the rubbing cloth is suppressed, the charge of the alignment film can be suppressed to a low level.

As described above, the rubbing cloth 5 of this embodiment is
Even if the rubbing treatment is performed by rubbing the alignment film, the charge is neutralized by the anti-charge dielectric fiber provided under the rubbing cloth 5, and the charging of both the rubbing cloth 5 and the alignment film can be suppressed to a low level. Therefore, the possibility of discharge not only between the rubbing cloth 5 and the alignment film but also between the transparent electrodes is eliminated, and the discharge breakdown of the alignment film due to the discharge can be prevented.
Therefore, it is possible to manufacture a liquid crystal display element having good display quality without alignment film defects.

In addition to the above embodiment, the rubbing treatment may be performed by a rubbing device using a rubbing cloth formed by directly weaving the anti-charge dielectric fiber into the mother fiber.

FIG. 2 is a sectional view showing the structure of the rubbing cloth 5 of the liquid crystal display device manufacturing apparatus according to another embodiment.
[Fig. 3] is an enlarged view of a portion C in Fig. 2.

As shown in FIG. 2, the rubbing cloth 5 is composed of a base cloth portion 21 in which fibers are woven, and fiber bristles 22 raised from the base cloth portion 21.

Then, as shown in FIG. 3 which is an enlarged view of the portion C shown in FIG. 2, the base cloth portion 21 of the rubbing cloth 5 is a warp yarn of an anti-charge dielectric fiber using the above-mentioned Soldion (trade name) or the like. The weft yarn is used as the weft yarn 31, and the weft yarn 32 is woven with normal fibers.

This embodiment is characterized in that the fibers themselves of the rubbing cloth 5 are woven with anti-charge dielectric fibers. Therefore, when the rubbing cloth 5 is positively charged by the rubbing treatment, the warp yarns 31 of the anti-charge dielectric fiber woven in the fibers are immediately negatively charged and the electric charges are neutralized in the rubbing cloth 5. It

Therefore, even in the liquid crystal display device manufacturing apparatus in which the anti-charge dielectric fiber is woven in the rubbing cloth, no discharge occurs between the rubbing cloth and the alignment film and between the transparent electrodes during the rubbing processing, and the rubbing processing is performed. It is possible to prevent the alignment film from being destroyed by electric discharge, and it is possible to manufacture a liquid crystal display element having good display quality.

[0042]

According to the first aspect of the present invention, since the anti-charge dielectric fiber is provided in or near the rubbing cloth to be subjected to the rubbing treatment, the charge charged on the rubbing cloth is the anti-charge dielectric fiber. It is neutralized by the induced charge of the liquid crystal, the discharge does not occur between the rubbing cloth and the alignment film on the substrate and between the transparent electrodes, and the alignment film is prevented from being destroyed by the discharge, and the display quality of the liquid crystal display element is kept good. You can

According to the second aspect of the present invention, since the rubber mat in which the anti-charge dielectric fiber is mixed in the rubber member is laid under the rubbing cloth, the charge opposite to the electric charge of the rubbing cloth is the anti-charge of the rubber mat. Equal amounts of the dielectric fibers are produced and electrically neutralized, preventing the alignment film from being damaged by discharge,
The display quality can be improved.

According to the third aspect of the present invention, since the anti-charge dielectric fiber is woven in the base cloth portion of the rubbing cloth, the charge charged in the rubbing cloth is woven in the base cloth portion of the rubbing cloth. In addition to being electrically neutralized by the induced charges of the organic fibers, it also neutralizes the charges generated in the alignment film on the substrate, preventing the alignment film from being destroyed by discharge and improving the display quality of the liquid crystal display element. Can be kept.

According to the fourth aspect of the present invention, the rubbing cloth is attached to the metallic rotating drum, and while the rotating drum is rotated, the alignment film coated on the substrate is rubbed in a certain direction to align the liquid crystal molecules. Since the direction is controlled, the rubbing process can be performed efficiently and accurately, and the rubbing cloth electrically charged by the rubbing process is electrically neutralized by the anti-charge dielectric fiber during one rotation. Is prevented.

[Brief description of drawings]

FIG. 1 is a plan view of a rubbing device.

FIG. 2 is a cross-sectional view showing a structure of a rubbing cloth of a liquid crystal display element manufacturing apparatus according to another embodiment.

FIG. 3 is an enlarged view of a portion C in FIG.

[Explanation of symbols]

 1 Rubbing Device 2 Rotating Drums 3a, 3b Rotating Shaft 4 Rubber Mat 5 Rubbing Cloth 6 Moving Stage 7 Glass Substrate 21 Base Cloth 22 Fiber Wrists 31 Warp 32 Warp

Claims (4)

[Claims] 1. A liquid crystal display device manufacturing apparatus for rubbing an alignment film, which regulates the alignment direction of liquid crystal molecules filled in a liquid crystal cell, with a rubbing cloth, wherein the rubbing treatment is carried out in or near the rubbing cloth. An apparatus for manufacturing a liquid crystal display element, characterized in that an anti-charge dielectric fiber is provided. 2. The liquid crystal display element manufacturing apparatus according to claim 1, wherein the anti-charge dielectric fiber is mixed in a mat-shaped rubber member and laid under the rubbing cloth. 3. The liquid crystal display element manufacturing apparatus according to claim 1, wherein the anti-charge dielectric fiber is woven into a base cloth portion of the rubbing cloth. 4. The rubbing cloth is provided on a peripheral surface of a metallic rotary drum, and the rotary drum is rotated to rub the alignment film in a predetermined direction, according to any one of claims 1 to 3. The liquid crystal display device manufacturing apparatus according to.