JPH04113320A - Orientation treatment of substrate for liquid crystal display element - Google Patents

Abstract

PURPOSE:To obtain an optimum rubbing pressure in spite of the presence of some fluctuations in the amt. of pushing the piles to an oriented film and to eliminate the need for the strict control of the amt. of pushing piles by installing a heating means to a roller wound with a rubbing cloth. CONSTITUTION:The heater 6 is built-in the roller 5 wound with the rubbing cloth 4 and the outside surface of the roller 5 is uniformly heated to uniformly heat the cloth 4. The temp. of the piles 4a is set at 50 to 100 deg.C. The rigidity of the piles 4a is weaker than at the time of ordinary temp. and, therefore, if the surface of the oriented film 3 on a glass substrate 1 is rubbed in the state of heating the cloth 4 in such a manner, the amt. of pushing the piles 4a necessary for attaining a desired rubbing pressure increases. Then, the drastic change in the rubbing pressure is prevented in spite of the presence of some fluctuations in the amt. of pushing the piles 4a to the oriented film 3.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides a method of rubbing an alignment film on a substrate with a rubbing cloth wrapped around a roller when manufacturing a liquid crystal display element (hereinafter abbreviated as LCD). The present invention relates to an alignment treatment method for an LCD substrate.

[Conventional technology]

A rubbing method is one method for aligning liquid crystal molecules in an LCD cell in a predetermined direction. This rubbing method is applied to LCD
An alignment processing method in which the surface of an alignment film applied to cover transparent electrodes on a glass substrate is rubbed in a specific direction with a pile of rubbing cloth wrapped around a roller during the production of It is.

That is, as shown in FIG. 2, a transparent electrode 2 is patterned on a glass substrate 1, and an alignment film 3 is formed on this transparent electrode 2.
After coating and forming, the glass substrate 1 is placed on a rubbing table (not shown), and while rotating the roller 5 wrapped with rubbing cloth 4 such as rayon or nylon in the direction of the arrow A, the glass substrate 1 is placed in the direction of the arrow B.
By moving the pile 4 of the rubbing cloth 4 in the direction
a rubs the surface of the alignment film 3, and the alignment film 3 is stretched along the direction of arrow B (rubbing direction), so that the long axis direction of the liquid crystal molecules becomes oriented in a direction parallel to the rubbing direction. .

[Problem to be solved by the invention]

By the way, in such a rubbing arrangement process, the tilt angle of the liquid crystal molecules changes depending on the contact pressure of the rubbing cloth 4 against the alignment film 3, so-called rubbing pressure. Management is required to set and maintain the pressure. Especially STN type LC
In D, if the pushing amount of the pile 4a of the rubbing cloth 4 against the alignment film 3 changes slightly, the rubbing pressure changes significantly, so in order to achieve the optimum rubbing pressure, the pushing amount of the pile 4a must be strictly controlled. The complexity of having to manage the system was a factor in reducing productivity.

Therefore, an object of the present invention is to provide a method for aligning an LCD substrate, which solves the problems of the prior art described above and allows easy management of rubbing pressure.

[Means to solve the problem]

The object of the present invention described above is to provide a method for aligning an LCD substrate, in which an alignment film on a substrate is rubbed in a specific direction with a rubbing cloth while rotating a roller wrapped with a rubbing cloth. This is achieved by adding .

[For production]

According to the above means, since the rubbing cloth is heated and the stiffness of the pile is weakened, the rubbing pressure hardly changes even if there is slight variation in the amount of pushing of the pile into the alignment film, and therefore the amount of pushing of the pile must be strictly controlled. No need to manage.

〔Example〕

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

FIG. 1 is an explanatory diagram showing a rubbing orientation processing method according to an embodiment of the present invention, and parts corresponding to those in FIG. 2 are given the same reference numerals.

In FIG. 1, the roller 5 wrapped with the rubbing cloth 4 has a built-in heater 6, and by uniformly heating the outer surface of the roller 5 with the heater 6, the rubbing cloth 4 is heated uniformly. The temperature of the pile 4a can be set at 50 to 100°C. When the surface of the alignment film 3 on the glass substrate 1 is rubbed with the rubbing cloth 4 heated in this way, it is difficult to achieve the desired rubbing pressure because the stiffness of the pile 4a is weaker than at room temperature. The amount of push-in of the pile 4a required for this is larger than in the prior art. Therefore, even if there is slight variation in the amount of pushing of the pile 4a into the alignment film 3, the rubbing pressure will not change significantly, and the desired rubbing can be achieved by simply setting the amount of pushing of the pile 4a relatively roughly. pressure is now possible.

In this way, in the above embodiment, the rubbing cloth 4 is heated by the heater 6 to weaken the stiffness of the pile 4a.
The rubbing pressure required to obtain the desired tilt angle can be easily controlled, and productivity can be expected to improve. Further, since the diameter of the roller 5 is about 50 to 100 mm, it is easy to uniformly heat the rubbing cloth 4 with the heater 6, and variations in rubbing pressure due to temperature unevenness are also avoided.

It should be noted that the shape and mounting position of the heater 6 are not limited to those in the above embodiments, as long as the rubbing cloth 4 can be heated uniformly.

〔Effect of the invention〕

As explained above, according to the present invention, the heating means attached to the roller uniformly heats the rubbing cloth and weakens the stiffness of the pile, so there is some variation in the amount of pushing of the pile into the alignment film. However, the rubbing pressure hardly changes, and therefore, the rubbing pressure necessary to obtain the desired tilt angle can be easily managed, which has an excellent effect of improving productivity.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a rubbing orientation processing method according to an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing a rubbing orientation processing method according to a conventional diagram. 1...Glass substrate, 3...
・Alignment film, 4...Rubbing cloth, 4a...
・・・・・・Pyle, 5・・・・・・・・・Laura,
6...... Heater.

Claims (1)

[Claims] A method for aligning a substrate for a liquid crystal display element, in which an alignment film on a substrate is rubbed in a specific direction with the rubbing cloth while rotating a roller wrapped with a rubbing cloth, characterized in that a heating means is attached to the roller. A method for aligning a substrate for a liquid crystal display element.