摘要:
Novel derivatives of cyclic and acyclic terpenoid alcohols, having general formula (I) X-(CO)n-O-T1, where n = O or 1, T1 is a terpenoid group and X is a combination of cyclic groups, eg phenyl, cyclohexyl and pyrimidyl. X preferably contains up to three cyclic groups. Preferred derivatives are esters of cyclic terpenoid alcohols, eg menthol, borneol and isopineocampheol, eg formula (II) (-)-menthol. Ferroelectric smectic liquid crystal mixtures and devices containing these derivatives as chiral dopants in a tilted smectic host are also described. The properties of various other derivatives of terpenoid alcohols of formula (I) are also described, eg those of neomenthol, isolongifolol, fenchol, carveol, myrthenol, nopol, citronellol, perilla alcohol and dihydrocitronellol.
摘要:
Ferroelectric smectic liquid crystal mixtures are provided consisting of two constituents; a smectic host and another containing a chiral compound in which rotation of the chiral centre relative to the molecular core is sterically hindered, so that the chiral compound induces a high Ps in the mixture. A preferred class of chiral compounds is those derived from naturally occurring compounds with chiral groups, especially alpha-hydroxycarboxylic acids, amino acids and terpenoids, e.g. with chiral groups (I), (II), (III). The chiral group is incorporated into a compound containing a mesogenic combination of groups, e.g. with chains of cyclic groups and some mesogenic combinations are described.
摘要:
Novel compounds suitable for use as components of a ferroelectric smectic liquid crystal composition, which contain two or more chiral centers derived from optically active alpha-hydroxy carboxylic acids, secondary alcohols, and terpenoid alcohols. These units are combined with a mesogenic combination of cyclic groups. Preferred compounds contain two or more lactate groups, lactate and 2-octyl groups, or lactate and terpenoid groups in combination with phenyl groups. Ferroelectric smectic liquid compositions containing these compounds, and a device using them are also described.
摘要:
Compounds which may be used as a dopant or host in a ferroelectric chiral smectic liquid crystal mixture. The compounds are characterised in that they are derivatives of an X-hydroxy carboxylic acid and contain the chiral unit (I), in which Ro may be alkyl, alkoxy, halogen, formula (II), where b may be 0 to 3 and the phenyl ring may be substituted, and a is 0 or 1. The chiral unit is combined with a range of mesogenic combinations of groups. Lactic acid derivatives are described in detail (i.e. Ro = methyl) together with various preparative routes, for example the compound formula (III), which has dopant properties in a range of hosts.
摘要:
Ferroelectric smectic liquid crystal mixtures are provided consisting of two constituents; a smectic host and another containing a chiral compound in which rotation of the chiral centre relative to the molecular core is sterically hindered, so that the chiral compound induces a high Ps in the mixture. A preferred class of chiral compounds is those derived from naturally occurring compounds with chiral groups, especially alpha-hydroxycarboxylic acids, amino acids and terpenoids, e.g. with chiral groups (I), (II), (III). The chiral group is incorporated into a compound containing a mesogenic combination of groups, e.g. with chains of cyclic groups and some mesogenic combinations are described.
摘要:
Fluorinated 4''-cyano substituted terphenyls of general formula (I), wherein R1 is selected from alkenyl, H, R, RO and RCO where R is alkyl or perfluoroalkyl containing up to 12 carbon atoms, n is 1, 2 or 3 and the lateral fluorosubstituent(s) may be in any of of the available substitution positions are provided. These have liquid crystalline properties and may be used as components of liquid crystal materials.
摘要:
A light modulating material is disclosed, comprising a solid, light transmissive, polymeric matrix having dispersed within said matrix droplets of a liquid crystalline composition, wherein said composition is a mixture of at least 2 compounds, at least one of said compounds having general formula (I), where n is 1 or 2, the fluorine substituent(s) may be in any of the available substitution positions and R1 is C¿1-12? alkynyl, hydrogen, R, RO or RCO where R is alkyl or perfluoroalkyl and at least one other of said compounds having general formula (II), where m is 0 or 1 and R?2¿ is hydrogen or C¿1-12? alkyl or alkoxy.
摘要:
Novel cyanohydrin derivatives of general formula (I) wherein R1 is hydrogen, alkyl, alkoxy, perfluoroalkyl or perfluoroalkoxy, R2 is alkyl, r is 1 to 10, n and m are 0 or 1, provided if both n and m are 0 then X is (II) or (III), where (F) indicates one or more optional fluorines, p is 0 or 1, Z is a single bond if p is 0 and COO if p is 1; and if one or both of n or m are 1 then X is (IV), where each ring A, B and C is phenyl, fluoro- or chloro-phenyl, cyclohexyl, pyrimidyl, pyridyl, or dioxanyl, A, B and C are single bonds or linking groups, and (a + b + c) is 2 or 3. Liquid crystal materials containing these compounds are also described.
摘要:
Nouveaux dérivés d'alcools de terpénoïdes cycliques et acycliques ayant la formule (I) X-(CO)nO-T1, où n = O ou 1, T1 est un groupe de terpénoïdes et X est une combinaison de groupes cycliques, par ex. phényle, cyclohexyle et pyrimidyle. X contient de préférence jusqu'à trois groupes cycliques. Des dérivés préférés sont des esters d'alcools de terpénoïdes cycliques, par ex. menthol, borneol et isopinéocampheol, par ex. formule (II) (-)-menthol. Des mélanges et dispositifs à cristaux liquides smectiques ferroélectriques contenant ces dérivés sous forme de dopants de chiralité dans un hôte smectique renversé sont également décrits. Les propriétés de divers autres dérivés d'alcools de terpénoïdes de formule (I) sont aussi écrites, par ex. celles de néomenthol, isolongifolol, fenchol, carvéol, myrthénol, nopol, citronellol, alcool de perilla et dihydrocitronellol.