New liquid crystal chemical compound, the nematic liquid crystal constituent and the Liquid Crystal Display null general expression which

摘要

PROBLEM TO BE SOLVED: To obtain a novel liquid crystal compound which is excellent in responsiveness and viscoelasticity, large in optical birefringence, of a wide driving temperature range and is useful as a liquid crystal material, for example, an electrooptical display material. ;SOLUTION: This liquid crystal compound is represented by formula I (R¹⁰ is a 1-10C alkyl), typically 4-(3-butenyl)-4'-alkylbiphenyl. The compound of formula I is prepared by subjecting a benzaldehyde derivative as a starting substance to the Wittig's reaction and treating the product with an acid. The nematic liquid crystal composition preferably contains 20-40wt.% of a compound of formula II (R¹¹ is a 1-5C alkyl) and 20-90wt.% of a liquid crystal composition containing a compound with Δε of ≥+2, and the composition has a Δε of ≥3, a TN_-1 of ≥70°C and the crystalline phase or T→N of ≤10°C.;COPYRIGHT: (C)1997,JPO