Bayer Aktiengesellschaft

Erich Kramer

Horst Nickel

Karl-Heinz Schundehutte

Hermann Henk

Karl H Schundehutte

Fritz Puchner

Hermann Goebel

Wolf-Eckhard Bleck

Wolf Eckhard Bleck

A metal free azo dyestuff of the formula ##STR1## in which K is the radical of a coupling component of pyridone, and

Reactive fluorotriazinylaminonaphthotriazolyphenylazopyridone or

Salts of acetoacetylamino-arylsulphonic acids, of the formula ##STR1## wherein R denotes an optionally substituted benzene or naphthalene nucleus,

Concentrated, aqueous solutions of salts of

Optionally metallized azo dyestuffs which in the form of the free acid correspond to the formula ##STR1## wherein K is the radical of a benzene, naphthalene, pyrazolone, pyridone, pyrimidone, acetoacetic acid arylide or aminopyrazole coupling component;

Azo reactive dyestuffs having an aryl-triazinyl-aryl diazo component

New disazo and polyazo dyestuffs which, in the form of the free acid, correspond to the general formula ##STR1## wherein K, R, m and n have the meaning indicated in the description, the use of these dyestuffs for dyeing and printing cellulose fibre materials and leather, and concentrated solutions containing azo dyestuffs according to formula (I).

Disazo and polyazo dyestuffs

The application relates to new azo dyestuffs which, in the form of the free acid, correspond to the general formula ##STR1## in which D, R, m and X have the meaning indicated in the description, their preparation and their use for dyeing and printing cellulose-containing materials, in particular paper and cotton.

Water-soluble azo dyestuffs

The compound which corresponds to the formula ##STR1## is suitable for the preparation of azo dyestuffs.

Benzotriazoles useful as azo dyestuff intermediates

The invention relates to the preparation of concentrated solutions of azo dyestuffs containing ionic groups, by precipitating during the diazotization and/or coupling reaction and/or after the coupling reaction the foreign ions which lower the solubility of the dyestuffs and separating off these ions as sparingly soluble salts. In this way dyestuff solutions which are stable to storage at room temperature and have a dyestuff content of 10 to 50 percent by weight are obtained.

Process for the preparation of concentrated dyestuff solutions

Para-coupled products of the 1-naphthol series can be destroyed in the presence of the ortho-coupled product by reduction with salts of dithionous acid or of hydroxymethanesulphinic acid or with hydrazine optionally in the presence of redox-catalysts.

Process for the selective destruction, by reduction, of p-coupled

Stable, concentrated solutions of anionic dyestuffs are prepared by reacting the alkali metal or ammonium salts of anionic dyestuffs and brighteners, which are usually obtained from the industrial preparation process, in water-soluble organic solvents, optionally in the presence of water, with salts of nitrogen bases which impart hydrophilic properties, in accordance with the reaction equation

Process for the preparation of concentrated solutions of anionic

The invention relates to polyazo dyestuffs of the formula ##STR1## in which R denotes hydrogen, methyl or chlorine,

Polyazo dyestuffs having a dianisidine component, a diaminophenyl

The invention relates to the preparation of storage-stable, concentrated solutions of urea compounds of the formula

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Bergisch-Gladbach, Germany

Erich Kramer