Reorientational Motion of Polymer-Stabilized Ferroelectric Liquid Crystals

Abstract

A polymer-stabilized ferroelectric liquid crystals (PSFLCs), in which photocurable mesogenic monomers are doped into an FLC and then a UV photocure is carried out in the SmC* phase under the application of a bipolar AC electric field, can exhibits monostable and V-shaped electrooptical characteristics. In this research, the time-resolved ellipsometry is applied to the PSFLCs, and we investigate the dependence of the molecular reorientational motion of the PSFLC on the photocuring condition such as the tilt angle which FLC molecules take in the photocure stage. The measurement results show that the dynamic behavior of PSFLC-molecular reorientation strongly depends on the photocuring condition of the tilt angle in addition to the concentration of polymer. Furthermore, the molecular reorientation of the PSFLC is 2-steps motion originated in the difference of the threshold voltage between near and far from polymer.

Keywords:

• ferroelectric liquid crystal
• photocure
• polymer stabilization
• reorientation
• tilt angle

Acknowledgments

The authors thank Mr. H. Fukuro and Mr. H. Endoh of Nissan Chem. Ind. for supplying polyimide materials. We also thank to Dr. H. Takatsu and Dr. H. Hasebe of Dainippon Ink and Chemicals for supplying photocurable mesogenic materials.