Orientation Patterning of Liquid Crystals by UV-Irradiated Polysilane Oriented Films

ABSTRACT

We prepared a highly oriented thin film of the simplest polysilane, poly(dimethylsilylene) (PDMS) by friction transfer method. It had an ability of aligning liquid crystals. A liquid crystal, 4-cyano-4′-n-pentylbiphenyl (5CB) sandwiched between oriented PDMS layers was uniformly oriented. The molecular axis of 5CB lay in parallel to the direction of PDMS chains. PDMS films could be easily photooxidized by UV light irradiation. 5CB between UV-irradiated PDMS oriented in the different manner from that between non-irradiated PDMS. The PDMS orienting films could be patterned by irradiation with a shadow mask and the orientation of 5CB induced by them was patterned.

Keywords:

• friction transfer
• liquid crystals
• orientation
• patterning
• polysilanes
• UV-irradiation

Acknowledgments

The authors wish to thank to Dr. Keiko Tawa (AIST) for kind cooperation with the IR measurements.