摘要 |
Alkenyl-terminal liquid crystal compounds (I) are new. Liquid crystal compounds of formula (I) are new. R = 2-15C alkenyl optionally substituted with CN, CF3 or halo, in which one or more CH2 groups can be replaced with O, S, CH=CH, ethynylene, OCO or COO; A<1>, A<2> = optionally halogenated 1,4-cyclohexenylene or 1,4-cyclohexylene in which 1-2 CH2 groups can be replaced with O or S; optionally halogenated 1,4-phenylene in which 1-2 CH groups can be replaced with N; or piperidine-1,4-diyl, 1,4-bicyclo(2.2.2)octylene, phenanthrene-2,7-diyl, naphthalene-2,6-diyl, decalin-2,6-diyl, tetralin-2,6-diyl or fluorene-2,7-diyl, all optionally halogenated; X = F, Cl, CN, NCS, SF5 or optionally halogenated 1-5C alkyl, alkoxy, alkenyloxy or alkenyl; Z<1>, Z<2> = COO, OCO, CF2O, OCF2, CH2O, OCH2, CH2CH2, (CH2)4, C2F4, CH2CF2, CF2CH2, CF=CF, CH=CH, ethynylene or single bonds, at least one being CF2O or OCF2; a, b = 0-2; L<1>-L<3> = H, F or Cl. Independent claims are also included for: (1) a liquid crystal medium comprising at least two mesogenic compounds and containing at least one compound (I); (2) and electrooptic display comprising the liquid crystal medium of (1). |