Abstract

A new cyclic chiral azobenzene compound Azo-o-Bi was synthesized, which exhibits photochemically reversible cis-trans isomerization in both organic solvents and liquid crystal hosts. When doping into a nematic liquid crystal, it displays high helical twisting power (HTP, β) and a large change in HTP (Δβ) due to photoisomerization. Therefore, we are able to reversibly tune the reflection colors from near-IR to blue using irradiation with light. For weak UV light irradiation, a broadband reflection film with pitch gradients can be obtained with superior stability in the dark. This stability is associated with the cyclo-shape of the Azo-o-Bi and the high viscosity of the host liquid crystal. The latter reduces the diffusion contribution of isomers to a negligible level. The spatial and temporal control of the light irradiation can be used to photoaddress the CLC with RGB reflection colors and white-on-black reflective displays.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.