Patent ID: 6805923
Filing Date: 2004-10-19
Classification: C09K

Abstract:
A liquid-crystalline medium comprising a mixture of polar compounds having positive dielectric anisotropy, wherein said medium comprises one or more compounds of formula I in whichR is H, an alkyl or alkenyl radical having up to 15 carbon atoms which is unsubstituted, monosubstituted by CN or CF3 or at least monosubstituted by halogen, where one or more CH2 groups in these radicals may also, in each case independently of one another, be replaced by â€”Oâ€”, â€”Sâ€”, â€ƒâ€”C&boxH;Câ€”, â€”COâ€”, â€”COâ€”Oâ€”, â€”Oâ€”COâ€” or â€”Oâ€”COâ€”Oâ€” in such a way that O atoms are not linked directly to one another, L1 and L2 are each, independently of one another, H or F, â€”Aâ€” is â€ƒand Y is F, Cl, halogenated alkyl, halogenated alkoxy, halogenated alkenyl, halogenated alkylalkoxy or halogenated alkenyloxy having up to 7 carbon atoms: and said medium further comprises one or more compounds selected from formulae II, III, IV, V, VI, VII, VIII or IX: wherein R0 is n-alkyl, oxaalkyl, fluoroalkyl or alkenyl, in each case having up to 7 carbon atoms, X0 is F, Cl, or halogenated alkyl, alkenyl or alkoxy in each case having 1 to 6 carbon atoms, Z0 is â€”C4H8â€”, â€”CF2Oâ€”, â€”OCF2â€”, â€”CF&boxH;CFâ€” or â€”C2F4â€”; Y1 and Y2 are each F, Y3 and Y4 are each, independently of one another, H or F, and r is 0 or 1, and comprises one or more compounds of formula IVa wherein R0 is n-alkyl, oxaalkyl, fluoroalkyl or alkenyl, in each case having up to 7 carbon atoms, and X0 is F, Cl, or halogenated alkyl, alkenyl or alkoxy in each case having 1 to 6 carbon atoms.