US 4,921,632 A · Liquid crystal compounds and compositions

Abstract

Liquid Crystal compounds represented by the following formula are disclosed. ##STR1## wherein R and R' are independently selected from alkyl groups containing 1.about.20 carbon atoms; X is --O--, --O--CO--O-- or direct bond; A.sub.1 and A.sub.2 are independently cyclic groups (such as phenylene and biphenylene), said cyclic groups may be substituted with 1.about.4 fluorine, chlorine or bromine atoms, or 1 or 2 substituent groups selected from the group consisting of cyano, nitro and trifluoromethyl groups; Y is --CO--O--, --O--CO--, --C.tbd.C--, --CH.sub.2 O--, --OCH.sub.2 --, --CH.dbd.N--, --N.dbd.CH--, --N.dbd.N--, --CH.sub.2 S--, --SCH.sub.2 -- or direct bond; and * represents asymmetric atom providing optical activity.

Claims22

Dependent claims

A liquid crystal compound represented by the general formula (1):

##STR90## wherein R and R' are independently selected from alkyl groups containing 1.about.20 carbon atoms;
X is --O--, --O--CO--O-- or direct bond;
A.sub.1 and A.sub.2 are independently cyclic groups selected from the group consisting of ##STR91## said cyclic groups may be substituted with 1.about.4 fluorine, chlorine or bromine atoms, or 1 or 2 substituent groups selected from the group consisting of cyano, nitro and trifluoromethyl groups;
and Y is --CO--O--, --O--CO--, --C.tbd.C--, --CH.sub.2 O--, --OCH.sub.2 --, --CH.dbd.N--, --N.dbd.CH--, --N.dbd.N--, --CH.sub.2 S--, --SCH.sub.2 --;
and * represents asymmetric atom providing optical activity.

2 more elements

A liquid crystal composition, containing as components thereof a mixture of a plurality of liquid crystal compounds, said liquid compounds comprising at least one compound represented by the general formula (1):

##STR95## wherein R and R' are independently selected from alkyl groups containing 1.about.20 carbon atoms;
X is --O--, --O--CO--O-- or direct bond;
A.sub.1 and A.sub.2 are independently cyclic groups selected from the group consisting of ##STR96## said cyclic groups may be substituted with 1.about.4 fluorine, chlorine or bromine atoms, or 1 or 2 substituent groups selected from the group consisting of cyano, nitro and trifluoromethyl groups;
and Y is --CO--O--, --O--CO--, --C.tbd.C--, --CH.sub.2 O--, --OCH.sub.2 --, --CH.dbd.N--, --N.dbd.CH--, --N.dbd.N--, --CH.sub.2 S--, or --SCH.sub.2 -- and * represents asymmetric atom providing optical activity.

1 more element

Dependencies are inferred from the claim text.

Liquid crystal compounds and compositions

Life of this patent

Liquid crystal compounds and compositions

Life of this patent

Abstract

Claims22