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Structure-performance relation of liquid crystal photoalignment with in-situ formation of protection layers

Published online by Cambridge University Press:  16 June 2016

Kai-Han Chang  and
Liang-Chy Chien
Kai-Han Chang*
Affiliation:
Liquid Crystal Institute and Chemical Physics Interdisciplinary Program, Kent State University, Kent, OH 44242, U. S. A.
Liang-Chy Chien
Affiliation:
Liquid Crystal Institute and Chemical Physics Interdisciplinary Program, Kent State University, Kent, OH 44242, U. S. A.
*
*(Email: kchang1@kent.edu)
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Abstract

We demonstrate a stabilized liquid crystal photoalignment using a surface-localized polymer method. A protection layer is developed on a photoalignment layer (PAL) through phase separation of a mixture composed of reactive monomers (RMs) and liquid crystals (LCs). The RM is polymerized on the PAL which enhances its stability against heat and light with short wavelength. The effects of the concentration and molecular structure of RMs on the electro-optical response and surface anchoring of photoaligned LC device are studied. The concentration of RMs affects the effective cell gap of the LC device. The rigid core length of the RM structure modulates the surface anchoring strength of the alignment layer. Both effective cell gap and surface anchoring strength are key elements for the enhanced dynamic response of LC devices.

Keywords

liquid crystaldisplaypolymerization
Type
Articles
Information
MRS Advances , Volume 1 , Issue 52: Soft Materials and Biomaterials , 2016 , pp. 3517 - 3523
Copyright
Copyright © Materials Research Society 2016 

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References

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