摘要:
An optically active compound represented by the following formula (I): ##STR1## wherein R.sub.1 denotes an alkyl or alkoxy group having 1-18 carbon atoms; R.sub.2 denotes an alkyl group having 1-12 carbon atoms; A denotes ##STR2## X denotes and C* denotes an optically active asymmetric carbon atom. The optically active compound, when included as a component, provides a ferroelectric liquid crystal composition or device showing an improved electro-field response characteristic.
摘要:
A mesomorphic compound represented by the following formula (I): ##STR1## wherein R.sub.1 denotes a linear or branched alkyl group having 1-18 carbon atoms capable of including one or non-neighboring two or more methylene groups which can be replaced with at least one species of ##STR2## with the proviso that X denotes O or S and Y denotes halogen; R.sub.2 denotes a linear or branched alkyl group having 1-18 carbon atoms; A, B and D independently denote ##STR3## wherein Z.sub.1 and Z.sub.2 independently denote hydrogen, halogen, --CH.sub.3, --CN or --CF.sub.3 ; E denotes --CH.sub.3, --CH.sub.2 F or --CF.sub.3 ; and f and g independently denote 0 or 1. The mesomorphic compound is effective for providing a ferroelectric liquid crystal composition showing an improved response speed and also effective for suppressing occurrence of reverse domain.
摘要:
An optically active compound represented by the following formula (I): ##STR1## wherein R.sub.1 denotes a linear or branched alkyl group having 1-18 carbon atoms optionally including one or non-neighboring two or more methylene groups which can be replaced with --X-- or ##STR2## with the proviso that X denotes O or S and Y denotes halogen; R.sub.2 denotes a linear alkyl group having 4-8 carbon atoms: and C* denotes an optically active asymmetric carbon atom. The mesomorphic compound is effective for providing a ferroelectric liquid crystal composition showing improved response characteristics and also effective for suppressing occurrence of reverse domain.
摘要:
There is provided a liquid crystal compound represented by the following general formula (I), a liquid crystal composite including at least one kind of above liquid crystal compound and a liquid crystal device in which the liquid crystal composite is disposed between a pair of electrode substrates. ##STR1## In the above formula (I), R.sub.1 is a straight chain alkyl having 1-12 carbon atoms. R.sub.2 is a straight chain or branched chain alkyl, which may have a substituted radical, having 1-18 carbon atoms and in which one or more than two methylene, which do not adjoin, may be substituted by --Y--, ##STR2## --CH.dbd.CH--, or --C.vertline.C--. Y is O or S. A is --A.sub.1 -- or --A.sub.1 --A.sub.2 --, and B is --B.sub.1 -- or --B.sub.1 --B.sub.2 --. A.sub.1, A.sub.2, B.sub.1, and B.sub.2 each is selected from ##STR3## and a single bond. Z is hydrogen, halogen, cyano or methyl. X.sub.1 is a single bond when A is a single bond and is --CH.sub.2 O--, ##STR4## in other cases. n is 0 or 1, ##STR5## --OCH.sub.2 -- or --CH.sub.2 O, and D is a single bond, ##STR6## and *designates an asymmetric carbon atom.
摘要:
A mesomorphic compound represented by the following formula (I): ##STR1## wherein R.sup.1 denotes analkyl group having 1-18 carbon atoms; R.sup.2 denotes an alkyl group having 1-12 carbon atoms; A and B respectively denote ##STR2## Z.sup.1 and Z.sup.2 respectively denote --H, 'CH.sub.3, --OCH.sub.3, --CN or halogen; m and n respectively denote 0, 1 or 2 and p denotes 1 or 2 with proviso that m+n+p =2 or 3; X denotes a single bond, ##STR3## denotes an asymmetric carbon atom.
摘要:
A liquid crystal composition, comprising: at least one optically active mesomorphic compound having an asymmetric carbon atom to which a fluorine atom is directly bonded.
摘要:
An optically active mesomorphic compound is represented by the following formula (I): ##STR1## wherein R.sub.1 and R.sub.2 are respectively an alkyl group having 1 to 16 carbon atoms, and C* denotes an asymmetric carbon atom. The mesomorphic compound has a fluorine atom directly connected to the asymmetric carbon atom and is effectively used as a liquid crystal component providing an increased spontaneous polarization and an improved responsiveness.
摘要:
An optically active, generally mesomorphic compound represented by the following formula (I): ##STR1## wherein R.sub.1 denotes an alkyl group having 1-18 carbon atoms, R.sub.2 denotes an alkyl group having 1-12 carbon atoms; X denotes a single bond, --O--, ##STR2## Y denotes a single bond, ##STR3## --CH.sub.2 O-- or --OCH.sub.2 --; Z denotes --OCH.sub.2 --, ##STR4## C* denotes an asymmetric carbon atom; k, m and n are respectively 0, 1 or 2 with proviso that k+m+n amounts to 2 or 3; and p is 1 or 2.
摘要:
A mesomorphic compound represented by the formula: ##STR1## wherein R.sub.1 denotes an alkyl group having 1-16 carbon atoms; R.sub.2 denotes an alkyl group having 2-10 carbon atoms; X denotes a single bond or --O--; Y denotes --OCH.sub.2 --, ##STR2## Z denotes a single bond, ##STR3## respectively and independently denote ##STR4## k, l and n are respectively 0, 1 or 2 satisfying the relation of k+l+n=2 or 3; C* denotes an asymmetric carbon atom. The mesomorphic compound, when added as a component, provides a liquid crystal composition showing an improved field respective characteristic or is effective in preventing occurrence of a reverse domain.
摘要:
An optically active 2-cyano-2-methyl-alkanoic acid represented by the formula: ##STR1## is produced by optical resolution of the corresponding racemic mixture thereof with an optically active amine and is reduced to provide an optically active 2-cyano-2-methyl-1-alkanol represented by the formula: ##STR2## wherein R.sub.1 denotes an alkyl groups having 3-10 carbon atoms, R.sub.2 denotes an alkyl group having 2-10 carbon atoms and C* denotes an asymmetric carbon atom. These compounds are characterized by having a CN group with a large dipole moment directly attached to an asymmetric carbon atom and are effective for controlling the liquid crystal state of a liquid crystal composition when added thereto.