(英) |
Previously, slit coater method as an liquid crystal (LC) alignment method has been demonstrated. LC material doped with a reactive-mesogen reveals a dependence of UV intensity of irradiation on LC alignment when coating on a glass substrate. The cause of LC alignment change have not been clarified yet, however, it seems that the surface of the polymerized reactive mesogen which is segregated on a substrate by UV irradiation gives some influence on an LC alignment.
In this study, direct observation of the segregated polymer-LC interface by means of atomic force microscope (AFM) is demonstrated. It should be highlighted that, the boundary between the segregated polymer-LC can be observed without removing LC layer, as a result, much information such as the original shape of the segregation layer can be obtained. The effect of UV-polymerization on the LC alignment under some UV irradiation conditions will be discussed. The relationship between the resultant surface free energy and the pre-tilt angle will also be shown. |