| 摘要 |
<p>Compounds of formula (I) are provided which may be used in a variety of devices including liquid crystal devices, piezoelectric devices, pyroelectric devices and in optical recording media, wherein X1 and X2 are independently selected from H, CN, COCH3, CO2CH3, m = at least 5; X3 and X4 are independently selected from formula (IA), wherein Y is selected from COO, OCO, O, S, CHOH, CHF, CH2; Q = (CH2)n wherein one or more non-adjacent methylenes may be replaced by O and n = 1-20; Z is selected from O, S, single covalent bond, COO, OCO; when Y is CH2 then n may also be 0; formula (A) represents any mesogenic group; X3 and X4 are also independently selected from H, OH, OCOR1, COOH, CO¿2?R?1, (CH¿2)pOH, (CH2)pCO2H, -(CH2)pOR1 or -(CH¿2?)pCO2R?1¿ and p = 1-20, R1 = H or C¿1-16?alkyl, when R?1¿ = C¿2-16?alkyl the terminal CH3 group may be replaced by Br or Cl; provided that at least one of X3 and X4 is selected from formula (IA).</p> |
