Process for the preparation of low-salt, liquid dyestuff preparations

摘要

Process for the preparation of low-salt liquid dyestuff preparations, characterized in that they are obtained by: a) diazotization of an aromatic amine, b) 2-fold coupling of the diazo component obtained according to a) to I-acid-urea, in the presence of an inorganic base and in the absence of an organic base, c) desalination and, if appropriate, concentration by means of a pressure permeation of the reaction mixture obtained according to b), so that an inorganic salt content of less than 1% by weight is achieved.