Liquid-crystalline compounds and liquid-crystalline media
AssigneeMerck Patent Gesellschaft Mit Bescrankter Haftung
InventorsAxel JANSEN, Helmut Haensel, Malgorzata Rillich
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Abstract
The present invention relates to liquid-crystalline compounds having two fluorinated biphenyl units, a terminal trifluoromethyl or trifluoromethoxy group and a —CF2O— bridge between the two fluorinated biphenyl units. The invention also relates to liquid-crystalline media prepared therewith and to liquid-crystal display devices (LC displays) containing these media.
Claims11
A compound of formula I
- in which
- L1 denotes H or F,
- R1 denotes an unsubstituted alkyl radical having 1 to 15 C atoms, in which one or more CH2 groups are each optionally replaced, independently of one another, by —C≡C—, —CH═CH—, —CF═CF—, —CF═CH—, —CH═CF—, —(CO)O—, —O(CO)—, —(CO)— or —O— in such a way that O atoms are not linked directly to one another,
- and
- R2 denotes CF3 or OCF3.
A liquid-crystalline medium according to claim 8, further comprising one or more compounds of formula II and/or III:
- in which
- R1 denotes an unsubstituted alkyl radical having 1 to 15 C atoms, in which one or more CH2 groups are each optionally replaced, independently of one another, by —C≡C—, —CH═CH—, —CF═CF—, —CF═CH—, —CH═CF—, —(CO)O—, —O(CO)—, —(CO)— or —O— in such a way that O atoms are not linked directly to one another,
- A2, A3 independently of one another, denote
- Z2, Z3 independently of one another, denote a single bond, CF2O, CH2CH2, CF2CH2, CF2CF2, CFHCFH, CFHCH2, (CO)O, CH2O, C≡C, CH═CH, CF═CH, or CF═CF, where asymmetrical bonding units may be oriented in either of both possible directions,
- X1 denotes F, Cl, CN, or
- alkyl, alkenyl, alkenyloxy, alkoxyalkyl or alkoxy having 1 to 3 C atoms, which is mono- or polysubstituted by F, and
- L1 to L4 independently of one another, denote H or F.
A liquid-crystalline medium according to claim 8, wherein in the compound of formula II or III, R1 is a straight-chain alkyl radical having 2 to 7 carbon atoms.
An electro-optical display device containing a liquid-crystalline medium according to claim 8.
Dependencies are inferred from the claim text.