Compounds containing a fluorobiphenylyl group

Abstract

Novel terphenyls having a relatively high clearing point and which are suitable for use in liquid crystal materials or in the preparation of compounds for use in such material are characterised by a formula: ##STR1## wherein: R.sub.1 is selected from H, alkyl, alkoxy, alkylcarbonyl, alkylcarbonyloxy and alkoxycarbonyloxy; R.sub.2 is selected from H, alkyl, alkoxy; X.sub.1 is selected from H and fluorine; X.sub.2 is selected from H and fluorine; and ##STR2## is selected from ##STR3## and ##STR4## provided that one of X.sub.1 and X.sub.2 is fluroine. Compounds wherein ##STR5## is ##STR6## or ##STR7## are generally useful as liquid crystal compounds.

Dependencies are inferred from the claim text.