Ferroelectric liquid-crystalline mixtures

US5378394A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Hans-Rolf Dubal · Königstein, DE
• Claus Escher · Mühltal, DE
• Takamasa Harada · Oberursel, DE
• Wolfgang Hemmerling · Pocking, DE
• Gerhard Illian · Frankfurt am Main, DE
• Ingrid Muller · Niedernhausen, DE
• Mikio Murakami · Kakegawa, JP
• Dieter Ohlendorf · Liederbach, DE
• Rainer Wingen · Hattersheim, DE

Key dates

• Filing date: Oct 28, 1991
• Grant date: Jan 3, 1995
• Expiry date: Oct 28, 2011

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09K19/588
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

The novel ferroelectric liquid-crystalline mixtures are based on at least two mixture components of the general formula (I) ##STR1## but additionally contain at least one optically active dope from one or more of the following groups PA0 a) optically active esters of tetrahydrofuran-2-carboxylic acid PA0 b) optically active aryl 2,3-epoxyalkyl ethers PA0 c) optically active 1,3-dioxolan-4-yl ethers. The ferroelectric LC mixtures have a high spontaneous polarization and facilitate substantial compensation of the pitch of the helix in a nematic phase.