In this paper we investigate a dye guest-host liquid crystal device based upon the bistable electro-optic effect in the smectic A phase. The dye used is a pentamethyldisiloxane-grafted disperse red 1 moiety; the liquid crystal host is an organosiloxane liquid crystal based upon cyanobiphenyl. It is shown that extremely high dye solubilities can be achieved e.g. greater than 38 % w/w, without dye separation or adverse effect on device electro-optic properties. The typical solubility limit in liquid crystals is of the order of several percent. It is proposed that the beneficial degree of dye accommodation is the result of microsegregation of constituent moieties into siloxane, alkyl chain and cyanobiphenyl core/chromophore regions.

Date Published: 9 May 2007
PDF: 6 pages
Proc. SPIE 6587, Liquid Crystals and Applications in Optics, 65871G (9 May 2007); doi: 10.1117/12.723041

Published in SPIE Proceedings Vol. 6587:
Liquid Crystals and Applications in Optics
Milada Glogarova; Peter Palffy-Muhoray; Martin Copic, Editor(s)