| abstract |
(57) [Summary] An optically active liquid crystal compound having a large helical twisting power and a liquid crystal composition which does not greatly extend the helical pitch by adsorption treatment. SOLUTION: An optically active compound represented by the following general formula I. Wherein R 1 and R 2 are H or C 1-18 alkyl, R 3 represents C 1-5 alkyl; A 1 -A 6 independently represents 1,4-phenylene, trans-1,4-cyclohexylene, cyclohexenylene or dioxane-2,5-diyl; 1 is a covalent bond or —CH 2 —, X 2 is a covalent bond or C 1-6 X 3 -X 6 is a covalent bond, -C 2 H 4 -, - indicating each - C 4 H 8. R 1 -R 3 and X 1 -X In 6 -CH 2 CH 2 - group -CH = CH- or -C≡C - it may be substituted with, -CH 2 not adjacent to each - is a group - It may be substituted by O-. P, Q, S, and T indicate 0 or 1, but P + Q + S + T ≦ 3. However, R 1 is an alkyl group having 1 to 3 carbon atoms, R 2 is a methyl group, A 1 and A 2 are both 1,4-phenylene, X 1 is a covalent bond, and X 2 is —CH (CH 3 ) − and P + Q + S + T = 0 are excluded. Embedded image |