| abstract |
The present invention relates to novel ethane derivatives of the formula 1 <IMAGE> in which R<a> is straight-chain alkyl having 1 to 8 carbon atoms, <IMAGE> or (m = 1 or 2; n = 0 or 1) and R<b> is straight-chain alkyl having 1 to 8 carbon atoms in which, in addition, one or two non-adjacent and in each case non-terminal CH2 group(s) may be replaced by -O-, and to the preparation of the compounds of the formula 1, to liquid-crystalline phases containing compounds of the formula 1, and to their use as components of liquid-crystalline phases. The compounds of the formula 1 have high chemical stability and only low conductivity. They are colourless and readily miscible with all common liquid crystals. Their use in liquid-crystalline phases results in broader mesophase ranges and reduced viscosity. The compounds of the formula 1 according to the invention are thus highly suitable for liquid-crystalline phases for electrooptical display devices, such as, for example, TN cells or guest-host cells. |