Liquid-crystalline compounds

US5626793A · kind A · utility

Assignee

• Merck Patent GmbH · DE

Inventors

• Volker Reiffenrath · Roßdorf, DE
• Herbert Plach · Darmstadt, DE
• Detlef Pauluth · Ober-Ramstadt, DE
• Reinhard Hittich · Seeheim-Jugenheim, DE
• Eike Poetsch · Mühltal, DE
• Thomas Geelhaar · Mainz, DE
• Georg Weber · Langen (Hessen), DE
• Ekkehard Bartmann · Langen (Hessen), DE

Key dates

• Filing date: Jun 5, 1995
• Grant date: May 6, 1997
• Expiry date: Jun 5, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09K2019/0444
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A nematic liquid crystalline medium having at least two liquid crystalline components with at least one being of formula I ##STR1## wherein R is H, a straight-chain alkyl or alkenyl radical having 1 to 15 carbon atoms, it also being possible to replace one or more CH.sub.2 groups in these radicals, independently of one another, by --O--, --S--, ##STR2## --CO--, --CO--O--, --O--CO-- or --O--CO--O-- in such a way that oxygen atoms are not linked directly to one another, PA0 Z.sub.1 and Z are each, independently of one another, --CH.sub.2 --CH.sub.2 --, --CH.dbd.CH--, --C.tbd.C-- or a single bond, and one of the radicals Z.sup.1 and Z is alternatively --(CH.sub.2).sub.4 -- or --CH.dbd.CH--CH.sub.2 CH.sub.2 --, PA0 A and A.sup.1 are each, independently of one another, trans-1,4-cyclohexylene in which, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by --O--, or are 1,4-phenylene which is unsubstituted or monosubstituted or disubstituted by fluorine and/or Cl atoms and in which, in addition, one or two CH groups may be replaced by N, PA0 m is 0, 1, 2 or 3, PA0 o and s are 0, 1 or 2, where (s+o) is >2. These liquid crystalline media find use in electro-optical displa…