Bayer Aktiengesellschaft

Helmut Herzog

Hans-Samuel Bien

Walter Hohmann

Reinold Schmitz

Detlef-Ingo Schutze

Gunter Gehrke

Helmut Seidler

Jurgen Schneider

Process for the preparation of a 6,13-dihydroquinacridone of the general formula (I) ##STR1## in which R.sup.1, R.sup.2, R.sup.3 and R.sup.4 designate hydrogen or substituents customary for quinacridone, characterized in that an optionally substituted dialkyl 2,5-di-(phenylamino)-3,6-dihydroterephthalate is heated to temperatures of 240.degree.-320.degree. C. in an essentially oxygen-free atmosphere in the presence of a dimethyl-diphenyl ether isomer mixture of the formula ##STR2## as the solvent and/or diluent, and a process for the preparation of optionally substituted quinacridone, characterized in that the resulting 6,13-dihydroquinacridone is oxidized in the customary manner.

Process for the preparation of 6,13-dihydroquinacridones and

A process has been invented for the preparation of 1,5-dichloroanthraquinone which comprises reacting 1,5-dichloroanthraquinone with chlorine in the presence of at least 50% by weight of liquid phthalic anhydride, relative to the weight of 1,5-dinitroanthraquinone employed. The 1,5-dichloroanthraquinone is known to be a valuable starting material for the preparation of various dyestuffs.

Process for the preparation of 1,5-dichloroanthraquinone

Process for dyeing and printing synthetic fibre materials using compounds of the formula ##STR1## in which R represents an optionally substituted phenyl radical, as well as special new dyestuffs within the above formula.

Nitroanthraquinones

Compounds of the formula ##STR1## wherein R represents cycloalkyl or the ##STR2## group wherein R.sub.1 and R.sub.2 denote alkyl and Y denotes hydrogen, chlorine, bromine, amino, alkylamino, cycloalkylamino, aralkylamino, arylamino, acylamino or arylmercapto, with the proviso that the nitro group is in the 5- or 8-position of the anthraquinone nucleus if Y denotes hydrogen

Anthraquinone compounds

The invention relates to a process for the preparation of water-insoluble chlorine-containing diaminodihydroxyanthraquinone dyestuffs. The process consists in that 2,8-dichloro-1,5-dinitroanthraquinone and/or 2,5-dichloro-1,8-dinitroanthraquinone is warmed with sulphur in concentrated sulphuric acid having a maximum SO.sub.3 content of 20% - possibly in the presence of boric acid - the resulting compounds are, if appropriate, post-halogenated and/or alkylated, preferably in the same reaction batch. The main advantage of this process is that it starts from 1,6- and/or 1,7-dichloroanthraquinone, for which there was hitherto no industrial use, but which unavoidably also arise during the synthesis 1,5- and 1,8-dichloroanthraquinones.

Anthraquinone dyestuffs

The invention relates to the preparation of partially known anthraquinone compounds of the formula ##STR1## wherein Z.sub.1 represents an optionally substituted hydrocarbon radical, Z.sub.2 represents hydrogen or alkyl, one X represents a chlorine atom and the other X denotes a hydrogen atom, by subjecting technical chloroanthraquinone mixtures to a fractional vacuum distillation and reacting the 1,6(1,7)-dichloranthraquinone fraction thereby obtained with amines of the formula HNZ.sub.1 Z.sub.2. Moreover the invention relates to novel compounds of the above formula wherein Z.sub.2 is H and Z.sub.1 is alkyl, alkenyl, aralkyl or cycloalkyl. They are good dyestuffs for synthetic fibres or dyestuff intermediates.

Process for the preparation of anthraquinone compounds

Compounds of the formula ##SPC1## In which R represents an alkyl, alkenyl, cycloalkyl or aralkyl radical, one X represents a nitro group and the other X represents hydrogen and their mixtures. They are very suitable for the dyeing of synthetic fibres, such as fibres of polyesters.

Process for dyeing and printing synthetic fiber materials using compounds of the formula ##SPC1## In which

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Bergisch-Neukirchen, undefined

Helmut Herzog