Patent ID: 6716491
Filing Date: 2004-04-06
Classification: C09K

Abstract:
A liquid-crystalline medium comprising polar compounds of positive dielectric anisotropy, said medium comprising one or more compounds of formula I whereinR1 is alkyl having 1 to 12 carbon atoms, alkoxy having 1 to 12 carbon atoms or an alkenyl group having 1 to 12 carbon atoms, in which, in addition, in each case one or two non-adjacent CH2 are each optionally replaced by â€”Oâ€”, â€”CH&boxH;CHâ€”, â€”COâ€”, â€”OCOâ€” or â€”COOâ€” in which O atoms are not linked directly to one another, Z1 and Z2 are each, independently of one another, â€”Oâ€”, â€”COOâ€”, â€”OCOâ€”, â€”CH2CH2â€”, â€”CH&boxH;CHâ€”, â€”CF2CF2â€”, CF2Oâ€”, â€”OCF2â€”, â€”CH2Oâ€”, â€”OCH2â€”, â€”CF&boxH;CFâ€” or a single bond, A1 and A2 are each, independently of one another, A2, if n is 1, can also be n is 0 or 1, and L1 and L2 are each, independently of one another, H or F. said medium further comprising one or more compounds of formulae II, III, IV, V and VI: â€ƒwherein, R0 is n-alkyl, oxaalkyl, fluoroalkyl or alkenyl, each having up to 7 carbon atoms, X0 is F, Cl, or halogenated alkyl, halogenated alkenyl or halogenated alkoxy, each having up to 6 carbon atoms, Y1 and Y2 are each, independently of one another, H or F, and r: is 0 or 1. wherein said medium has a clearing point of 85Â° C. or higher.