Bayer Aktiengesellschaft

Walter Hohmann

Klaus Wunderlich

Hans-Samuel Bien

Helmut Herzog

Werner Kuhnel

Helmut Seidler

Detlef-Ingo Schutze

Karl-Julius Reubke

Gunter Gehrke

Josef W Stawitz

Gerhard Berg

Vat dyestuffs containing at least 80% by weight of one or more of the compounds of the formula ##STR1## wherein A and B independently of one another represent --NHV, --NHW or --NHZ, in which

Vat dyestuffs of the trisanthraquinonylaminotriazine series

Nitrotrianthrimidecarbazoles of the formula ##STR1## in which the NO.sub.2 group is in the .alpha.- or .beta.-position and R.sub.1, r.sub.2 ; R.sub.3 and R.sub.4 designate hydrogen or halogen such as chlorine and bromine, their use as vat dyestuffs, a process for their preparation, and the use, as vat dyestuffs, of compounds which in the formula (I) have an NH.sub.2 group in place of the NO.sub.2 group.

Anthraquinone vat dyestuffs

A process has been developed for the preparation of mixtures of dinitroanthraquinones with a high content of 1,5- and 1,8- dinitroanthraquinone by nitration with nitric acid in the presence of sulphuric acid with heating wherein anthraquinone, 1-nitroanthraquinone or a mixture of them is treated with about 1.5 to about 2.5 times the amount by weight of nitric acid, relative to the feed material, in the presence of about 0.75 times to twice the amount by weight, relative to nitric acid, of sulphuric acid, the temperature first being kept in the range from room temperature to about 50.degree. C. until at least 50% of the starting material or materials has been dinitrated, then adjusting the temperature to about 50.degree. C. to about 70.degree. C. to complete the dinitration.

Process for the preparation of mixtures of dinitroanthraquinones with a

A process for the preparation of 1-amino-4-bromoanthraquinone-2-sulfonic acid or an alkali metal salt thereof by converting 1-aminoanthraquinone (which can be obtained by reduction of 1-nitroanthraquinone with sodium sulfide and/or sodium bisulfide or reaction of the 1-nitroanthraquinone with ammonia) by contacting the same with oleum at a temperature in the range of 90.degree. to 150.degree. C. optionally in the presence of an alkali metal sulfate and thereafter treating the so-sulfonated composition with bromine at a temperature in the range of from 60.degree. to 100.degree. C. 1-amino-4-bromoanthraquinone-2-sulfonic acid or an alkali metal salt thereof can be precipitated from the reaction mixture either by adjusting the sulfuric acid concentration thereof to 60 to 85 percent by weight or by stirring the reaction mixture into water, which optionally contains an alkali metal sulfate.

Process for the preparation of 1-amino-4-bromoanthraquinone-2-sulfonic

Fabrics of synthetic fibres, preferably polyester fibres, can be printed in clear blue shades in accordance with the transfer printing principle if dyestuffs of the formula ##STR1## wherein R represents an alkyl radical with 2-6 C-atoms, are used.

Transfer printing process

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

A process has been developed for the mononitration of anthraquinone to 1-nitroanthraquinone with nitric acid/sulphuric acid mixtures wherein anthraquinone is nitrated in a nitric acid/sulphuric acid mixture, in which the weight ratio of nitric acid to sulphuric acid is about 1:1 to about 2:1, in which the weight ratio of sulphuric acid to anthraquinone is about 0.5:1 to about 1:1 and in which the weight ratio of sulphuric acid to water is about 2.5:1 to about 5.5:1, the weight ratios relating to the sum of the materials employed, at temperatures in the range from about 45.degree. to 70.degree. C. until the anthraquinone content is less than 3% by weight, relative to the sum of the anthraquinone compounds.

Process for the mononitration of anthraquinone

Use of the dyestuffs of the formula ##STR1## wherein R, Y and X have the meaning given in the description, for the dyeing of synthetic textiles, especially those of aromatic polyesters, by the transfer printing process. Prints obtained are distinguished by good fastness in use properties.

Branched-chain alkyl amino anthraquinones

A process has been invented for the isolation of 1,6- and 1,7-dinitroanthraquinone by treating mixtures containing these isomers with nitrobenzene.

Process for the isolation of 1,6- and 1,7-dinitroanthraquinone

Anthraquinone dyestuffs of the general formula ##STR1## wherein IN EACH OF THE TWO ANTHRAQUINONE RADICALS SUBSTITUTED BY X, one X denotes chlorine and the other denotes hydrogen and

Process for dyeing textiles

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 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.

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Leverkusen, Germany

Walter Hohmann