Liquid-crystal mixture with a pleochroic anthraquinone dye, and method for producing such a dye

US4491532A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Gunther Scherowsky · Berlin, DE
• Alexander Moller · Gelnhausen, DE
• Gerd Heppke · Berlin, DE
• Burkhard Knippenberg · Berlin, DE

Key dates

• Filing date: Sep 10, 1981
• Grant date: Jan 1, 1985
• Expiry date: Sep 10, 2001

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09K19/603
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

Liquid-crystal mixture with a pleochroic anthraquinone dye of the general formula ##STR1## with R.sup.1, R.sup.3, R.sup.4, R.sup.6 =H, OH, OCH.sub.3, NH.sub.2, NHCH.sub.3, NO.sub.2, characterized by the feature that ##STR2## (R.sup.7 =H, alkyl, cycloalkyl, alkoxy, alkylmercapto, amino, alkylamino, dialkylamino, nitro, cyano, halogen), ##STR3## COOR.sup.9, CH.sub.2 --OR.sup.9 (R.sup.8 =H, alkyl, cycloalkyl, alkoxy, alkylmercapto, amino, alkylamino, dialkylamino, nitro, cyano, halogen); R.sup.9 =H, alkyl and either R.sup.1, R.sup.4 =H, OH, NH.sub.2, NHCH.sub.3, NO.sub.2, NHCH.sub.3, NO.sub.2, OCH.sub.3, where at least one of the two radical is an NH.sub.2 or an NHCH.sub.3, R.sup.3 =R.sup.6 =H, or R.sup.3, R.sup.6 =H, OH, NH.sub.2, NHCH.sub.3, NO.sub.2, OCH.sub.3, where at least one of the two radicals is an NH.sub.2 or an NHCH.sub.3, R.sup.1 =R.sup.4 =H.