Investigation of liquid crystal alignment on the photo-alignment material PM4Ch surfaces

We synthesized the new photo-alignment material, PM4Ch (poly (4-methacryloy loxy chalcone)). Good thermal stabilities of synthesized PM4Ch were obtaine d by TGA (Thermogravimetric Analysis) measurement. The electro-optical (EO) characteristics of the photo-aligned twisted nematic (TN)-LC display (LCD) , with linearly polarized UV exposure of normal direction on the PM4Ch surf ace were investigated, Monodomain alignments of the NLC by polarized UV exp osure of normal direction on the PM4Ch surface were observed. The excellent voltage- transmittance curves for the photo-aligned TN-LCD on the PM4Ch su rfaces were successfully obtained. Also, a fast response time for the photo -aligned TN-LCD on the PM4Ch surface can be achieved. Reduction of the DC v oltage for the photo-aligned TN-LCD decreases with increasing UV exposure t ime on the PM4Ch surfaces.