| 摘要 |
The present invention discloses a process for the preparation of lean salt liquid dyeing compound, characterized in that they are obtained by a) diazotation of an aromatic amine, b) double coupling of diazo components, which are obtained according to a) over I-acid-urea, in the presence of an inorganic base and in the absence of an organic base, c) elimination of salts and, if required, a pressure-permeation concentration of the reaction mixture obtained according to b), in such a way so that an inorganic salts content lower than 1 percent by weight is reached, relative to the liquid dyeing compound.
|
