A method of preparing concentrated solutions of lithium salts of 1:2 complex metal azo dyestuffs

摘要

1. Process for the preparation of concentrated solutions of the lithium salts of symmetrical and asymmetrical 1:2 chromium and cobalt complex azo dyestuffs in optionally water-containing organic water-miscible solvents by neutral to alkaline coupling and metallisation without intermediate isolation in optionally water-containing organic water-miscible solvents, characterised in that the pH adjustment for the coupling reaction is carried out using lithium compounds which have an alkaline reaction in water.