54641-22-4Relevant academic research and scientific papers
Development of novel chiral dopants to be used in ferroelectric liquid crystal system
Kayani, Zohra N.,Lewis, Robert A.,Naseem, Shahzad
, p. 74 - 88 (2013/05/08)
The study of chiral dopant and its application in liquid crystal system is one of the largest area of research in fluids leading to technological application in the field of display devices. Chiral dopant when mixed with achiral host mixture forms ferroelectric liquid crystal to be used in surface stabilised liquid crystal devices. 4-(pentyl, heptyl, nonyl)-2, 3 difluoro terphenyl nitriles and (S)-(-)-1-cyno-2-methylbutyl-4-pentyl-difluoroterphenyl- 4′-carboxylate were synthesised and mixed with achiral host mixture HM1 with the percentage of 3 and 7. Ferroelectric properties of synthesised FLC 1 were studied.
Cyanoalkyl difluoro-terphenyl-carboxylate chiral dopants
Kayani, Zohra N.,Lewis, Robert A.,Naseem, Shahzad
scheme or table, p. 11 - 19 (2012/08/13)
A liquid crystal like difluoroterphenyl chiral dopant was synthesized to match the dimensions of a host chiral dopant mixture. The melting point of the chiral dopants was decreased by increasing the length of the alkyl chain. The melting point of the chiral dopants also decreased when fluorine was on the same ring as the ester i.e. at 2″, 3″ position. These dopants were formulated with terphenyl host mixture and liquid crystal properties were assessed. New dopants, when added to the host mixture, maintain SmA1 but the SmC2 phase was reduced markedly. There was a decrease in spontaneous polarisation when fluorine was on the same ring as the ester i.e. at 2″, 3″ position. As the molecular weight of the chiral dopant increased (pentyl ↑ heptyl ↑ nonyl), spontaneous polarisation decreased.
The Synthesis of Optically Active Cyanohydrin Esters and Their Use as High Ps Dopants for Ferroelectric Displays
Chan, L. K. M.,Gray, G. W.,Lacey, D.,Scrowston, R. M.,Shenouda, I. G.,Toyne, K. J.
, p. 125 - 146 (2007/10/02)
This paper describes the reasoning underlying the design and synthesis of a range of cyanohydrin esters, specifically as high Ps dopants of host SC materials, for use in fast switching ferroelectric displays.Full synthetic details are given for the preparation of optically pure cyanohydrin esters from naturally occuring L-amino-acids; examples derived from (a) a D-amino-acid, (b) lactic acid are also given.Such materials provide excellent dopants which in suitable SC hosts provide mixtures with wide S*C ranges, good Ps values and long pitches, which switch rapidly at room temperature and may be multiplexed at video frame rates. - Keywords: ferroelectric materials, high Ps dopants, chiral cyanohydrin esters.
