Alignment material rubbing cloth

Here, mi, a, and Y are the effective contact density between the alignment material and the rubbing cloth, the contact area, and the jneld stress of the alignment material. If we assume that the contacts of the fibres of the rubbing cloth and the alignment material are a series of point contacts by a single fibre as shown in Pig. 2.23,... 

The rubbing machine is covered with a hood, and an exhaust fan is used to prevent the diffusion of the dust from the rubbing cloth and alignment material. After the rubbing process, a cleaning process is used to wash away particles of the rubbing cloth and alignment material from the surface of the substrate. 

Since bits of the rubbing cloth and pieces of alignment material are embedded on the substrate by the rubbing process, a cleaning step is required after rubbing. The substrates are cleaned by using a normal process with purified water and ultrasonic vibration, and then dried. 

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