Process for the preparation of solutions of cationic azo dyestuffs
Abstract
Abstract Concentrated stable solutions of cationic azo dyestuffs of the formula ##STR1## wherein A denotes the radical of an aromatic-carbocyclic or aromatic-heterocyclic diazo component, R denotes alkylene, R 1 denotes hydrogen or alkyl, R 2 denotes alkyl, alkenyl or aralkyl, R 3 denotes alkyl, R 4 denotes hydroxyalkyl with 2 or more C atoms, R 5 denotes halogen, alkyl, alkoxy, aryloxy, acyl or acylamino, m denotes 0, 1, 2, 3 or 4 and An .sup.(-) denotes a carboxylate ion, and wherein the cyclic and acyclic substituents can carry further non-ionic substituents, which solutions have a low salt content, are prepared by simultaneously reacting amines of the formula A--NH.sub.2 (II) coupling components of the formula ##STR2## and alkali metal nitrites or alkaline earth metal nitrites in aqueous carboxylic acids and, if appropriate, organic water-soluble solvents, and then separating off the alkali metal sulphates or alkaline earth metal sulphates which thereby crystallize out.
Inventors
- 👤 Karl Linhart
- 👤 Harald Gleinig
- 👤 Gunther Boehmke
- 👤 Kurt Breig
Bibliographic Details
Claims Analysis
Total Claims: 7References Cited (Backward Citations)
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