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We have previously reported that the surface of a substrate fabricated using the stripped film method gives a uniform orientation of both the nematic director and pretilt angle. However, this alignment layer generates only a low pretilt angle of about 1.5°. The stripped film surface fabricated using the substrate constructed with three kinds of organic film, polyvinyl alcohol base film (Vinylon film, KURARAY Co.), polyvinyl alcohol (PVA) adhesive agent and polyimide film (AL-3046, Japan Synthetic Rubber Co.), generated unique characteristics of the pretilt angle of nematic liquid crystals. We propose under certain process conditions, the stripped film surface is capable of generating a high pretilt angle of about 10° which is much higher than the pretilt angles of the polyimide and PVA alignment layers fabricated by the conventional rubbing method.

We investigate a new rubbing-free process for nematic liquid crystal (LC) alignment using the stripped film method. It was found that the direction of the nematic director, the pretilt angle and the tilt-up direction are determined by the peeling direction. The nematic director was aligned parallel to the peeling direction, and the pretilt angle increased in the direction opposite to the peeling direction. The value of the pretilt angle, 1.5°, was independent of the peeling speed. Device-quality alignment was realized on the surface of a stripped substrate.