NEW MATERIAL:A compound expressed by formula I (R1 is 1W8C alkyl or alkoxy; R2 is 1W8C alkyl; X is one covalent bond or ethane bond).

EXAMPLE: p-Hexyloxybenzoic acid-p'-[β-(2,3-dicyano-4-pentyl-phenyl)-ethyl]- phenylester.

USE: A liquid crystal display element material having very large minus dielectric anisotropy and excellent compatibility with other liquid crystal or non-liquid crystal, chemically stable and useful for display of clock, electronic calculator, instrument panel of vehicles, computer terminal, etc.

PREPARATION: A compound expressed by formula II is converted to acid chloride thereof using thionyl chloride and then the acid chloride is reacted with phenol in the presence of pyridine to provide a compound expressed by formula I.