Anti-ferroelectric liquid crystal composition and liquid crystal display
AssigneeMitsubishi Gas Chemical Company, Inc.
InventorsMasahiro Johno, Tomoyuki Yui, Takahiro Matsumoto, Yoshihisa Arai
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Abstract
An anti-ferroelectric liquid crystal composition consisting essentially of an anti-ferroelectric liquid crystal (A) and a ferrielectric liquid crystal (B) shows a low threshold voltage so that the driving voltage can be decreased, and the composition can give a liquid crystal display device utilizing a fast response time or switching among tristabile states, a distinct threshold voltage characteristic and excellent memory performance.
Claims9
An anti-ferroelectric liquid crystal composition consisting essentially of an eutectic mixture of at least one of an anti-ferroelectric liquid crystal (A) compound and at least one of a ferroelectric liquid crystal (B) compound,
- wherein the anti-ferroelectric liquid crystal (A) has a smectic A phase and has a melting point equal to or lower than room temperature and a tilt angle of at least 25.degree., and has a phase sequence of isotropic phase--smectic A phase--anti-ferroelectric phase--crystal phase,
- the anti-ferroelectric liquid crystal (A) is at least one compound selected from the group consisting of
- C.sub.8 H.sub.17 --O--Ph--Ph--COO--Ph(3-F)--COO--C*H(CH.sub.3)(CH.sub.2).sub.5 OC.sub.2 H.sub.5
- C.sub.8 H.sub.17 --O--Ph--Ph--COO--Ph(3-F)--COO--C*H(CF.sub.3)(CH.sub.2).sub.5 OC.sub.2 H.sub.5
- C.sub.8 H.sub.17 --O--Ph--Ph--COO--Ph(3-F)--COO--C*H(CH.sub.3)C.sub.8 H.sub.17
- C.sub.8 H.sub.17 --O--Ph--Ph--COO--Ph--COO--C*H(CF.sub.3)(CH.sub.2).sub.5 Oc.sub.2 H.sub.5
- and
- C.sub.9 H.sub.19 --O--Ph--Ph--COO--Ph--(3-F)--COO--C*H(CF.sub.3)(CH.sub.2).sub.5 OC.sub.2 H.sub.5,
- the ferroelectric liquid crystal (B) is at least one compound selected from the group consisting of
- C.sub.8 H.sub.17 --O--Ph--COO--Ph--Ph--COO--C*H(CH.sub.3)C.sub.4 H.sub.9
- C.sub.10 H.sub.21 --O--Ph--Ph--COO--Ph--COO--C*H(CH.sub.3)C.sub.5 H.sub.11
- C.sub.12 H.sub.25 --O--Ph--Ph--COO--Ph--COO--C*H(CH.sub.3)C.sub.7 H.sub.15
- C.sub.8 H.sub.17 --O--Ph--CH.sub.2 O--Ph--Ph--COO--C*H(CF.sub.3)(CH.sub.2).sub.2 OC.sub.2 H.sub.5
- C.sub.9 C.sub.19 --O--Ph--CH.sub.2 O--Ph--Ph--COO--C*H(CF.sub.3)(CH.sub.2).sub.2 OC.sub.2 H.sub.5
- C.sub.10 H.sub.21 --Ph--Ph--COO--Ph--COO--C*H(CH.sub.3)C.sub.6 H.sub.13
- C.sub.9 H.sub.19 --O--Ph--CH.sub.2 O--Ph--Ph--COO--C*H(CF.sub.3)CH.sub.2 COOC.sub.2 H.sub.5
- C.sub.8 H.sub.17 --O--Ph--Ph--COO--Ph--COO--C*H(CF.sub.3)CH.sub.2 COOCH.sub.3
- C.sub.8 H.sub.17 --O--Ph--Ph--COO--Ph--COO--C*H(CH.sub.3)CH.sub.2 OC.sub.6 H.sub.13
- C.sub.9 H.sub.19 --O--Ph--Ph--COO--Ph--COO--C*H(CH.sub.3)CH.sub.5 H.sub.11
- C.sub.12 H.sub.25 --O--Ph--Ph--COO--Ph--COO--C*H(CH.sub.3)C.sub.5 H.sub.11
- C.sub.11 H.sub.23 --O--Ph--Ph--COO--Ph--COO--C*H(CH.sub.3)C.sub.7 H.sub.15
- C.sub.10 H.sub.21 --O--Ph--CH.sub.2 O--Ph--Ph--COO--C*H(CF.sub.3)(CH.sub.2).sub.2 OC.sub.2 H.sub.5
- and
- C.sub.8 H.sub.17 --O--Ph--CH.sub.2 O--Ph--Ph--COO--C*H(CF.sub.3)CH.sub.2 COOC.sub.2 H.sub.5
- in which --Ph-- represents a benzene ring bonding to a p-position and C* represents an optically active carbon atom, and the ferroelectric liquid crystal (B) is contained in an amount sufficient to decrease a voltage required for driving the anti-ferroelectric liquid crystal (A).
Dependencies are inferred from the claim text.