57 Dichroitisches Material, vorwiegend in Form flüssigkri- stalliner Phasen, enthaltend mindestens einen Anthrachinonfarbstoff der Formel
in der
Y1, Y2, Y3, Y4 die in der Beschreibung angegebenen Bedeutungen haben,
neue Anthrachinonfarbstoffe sowie ihre Verwendung zum Färben von synthetischen Polymeren.
Production of aminonitrodihydroxyanthraquinones by partial reduction
申请人:BASF Aktiengesellschaft
公开号:US04048199A1
公开(公告)日:1977-09-13
The production of aminonitrodihydroxyanthraquinones of the formula: ##STR1## in which one X is OH and the other X is NO.sub.2 by partial reduction of the corresponding dinitrodihydroxyanthraquinone or mixtures thereof by heating at 80.degree.-250.degree. C in the presence of 1/2 to 5 times the weight thereof of an unsubstituted or substituted phenol. The reduction is accelerated by being carried out in the presence of a small amount such as 0.5-20 mol percent of an alkaline-reacting agent. Pure aminonitrohydroxyanthraquinones are obtained which are free from diaminodihydroxyanthraquinones.