초록 |
Photo-alignment methods have attracted increasing attention in recent year to replace rubbing method due to their potential abilities. However, photo-alignment methods are still limited to apply in industry due to low pretilt angle, low thermal stability. In this paper, we prepared polyimide (PI) blends with fluorinated PI to control pretilt angle. Photoreactive cinnamate was introduced by surface reaction. Atomic force microscopy images showed surface morphology change by addition of fluorinated PI with increasing alignment angle. Photo-reactive cinnamate moiety was introduced by interfacial reaction and photochemical reactivity was confirmed by contact angle and pretilt measurement. The pretilt angle of the LC cells was about 7.2° |