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EP0074523A1 Expired / Lapsed EP ⏱️ 0.0 years remaining

Liquid crystal materials containing anthraquinone dyes, and anthraquinone dyes

Assignee: Bayer AG
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Filing: 1982-08-24
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Granted: —
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Expires: 2002-08-24
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Abstract

Abstract 1. Liquid-crystalline material containing at least one anthraquinone dyestuff of the formula see diagramm : EP0074523,P10,F4 in which X represents H or see diagramm : EP0074523,P10,F6 it being possible for the rings A, B, C and D to carry 1, 2, 3, 4, or 5, preferably 1, 2 or 3, substituents from the series comprising alkyl which is optionally interrupted by -O-, -S- and/or -NR-, R denoting alkyl or aryl, cycloalkyl, aralkyl, alkoxy which is optionally interrupted by -O-, -S- or -NR-, R denoting alkyl or aryl, halogen, trifluoromethyl, nitro, optionally substituted amino, carboxylic acid derivative, sulphonic acid derivative or optionally substituted sulphonamide groups, wherein, in the case where X represents see diagramm : EP0074523,P10,F7 the four alpha-substituents on the anthraquinone ring are identical, and with the exception of 1,4,5,8-tetra(phenylthio)-anthraquinone and 1,4,5,8-tetra-(p-tert.-butylphenylthio)-anthraquinone.

Inventors

  • 👤 Rütger Dr. Neeff
  • 👤 Uwe Dr. Claussen

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-08 12:40
CPC Classifications
C; C09; C09B; C09B1/00; C09B1/56; C09B1/58; C09B1/585; C09K; C09K19/00; C09K19/52; C09K19/60; C09K19/603

Claims Analysis

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References Cited (Backward Citations)

DE2259970A1 Cited
FR2438112A1 Cited
GB2081736A Cited
GB2082196A Cited
EP0059095A1 Cited
EP0059036A1 Cited

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