POLYCYCLIC COMPOUND, LIQUID-CRYSTAL MATERIAL COMPOSED OF THE COMPOUND, AND LIQUID-CRYSTAL COMPOSITION AND LIQUID-CRYSTAL DEVICE CONTAINING THE MATERIAL

摘要

Disclosed is a polycyclic compound represented by the following formula (I): R<1>-X<1>-ÄA<1>-X<2>Ü-ÄA<2>-X<3>Ü-R<2> wherein R<1> is a (halogenated) alkyl group of 6 to 16 carbon atoms, X<1> is -O- group or a single bond, A<1> is a biphenylene group, a phenylene group or the like, A<2> is 1-fluoro-3,4-dihydronaphthalene or the like, X<2> and X<3> are each -COO-, a single bond or the like, and R<2> is an optically active group of 4 to 20 carbon atoms which has at least one asymmetric carbon atom. Also disclosed are a liquid crystal material consisting of the polycyclic compound, a liquid crystal composition comprising the liquid crystal material, and a liquid crystal element. This novel polycyclic compound is optically active and capable of being in a smectic phase in a wide temperature range including room temperature. The polycyclic compound can be used as a ferroelectric liquid crystal material or an antiferroelectric liquid crystal material. By the use of the liquid crystal material of the invention, a liquid crystal element having a quick response speed in a wide temperature range can be obtained.