| 摘要 |
PROBLEM TO BE SOLVED: To provide a chiral dopant which gives a large twisting power (HTP) and shortens the pitch of an induced spiral with the rise of temperature. SOLUTION: This chiral additive comprises at least one of optically active compounds represented by formula (1) [X<1> and X<2> are each independently (A<1> n1 -(B<1> )n2 -(A<2> )n3 -B<2> -R<3> (A<1> and A<2> are each 1,4-phenylene, trans-1,4- cyclohexylene, or the like; B<1> and B<2> are each a single bond, COO, OOC, or the like; R<1> is a 1 to 12c alkyl; n1, n2 and n3 are each 0, 1 or 2)] and exhibiting a plus wavelength shift and at least one of optically active compounds represented by formula (2) R<1> is Cq H2q+1 or its ester, ether or the like [(q) is 1 to 5]; R<2> is COOC*H(CH3 )CH2 CH(C2 H5 )2 or COOC*(CH3 )Cs H2s+1 [(s) is 4 to 9; C* is an asymmetric carbon atom]; Y is 1,4-phenylene or trans1,4- cyclohexylene; Z is a single bond, COO, COO-Ph, Ph-COO, or the like} and exhibits a minus wavelength shift.
|
