PREPARATION OF TRISAZO DIRECT DYES

The direct dye of formula (I) is prepared by (1) tetrazolating a benzidine-based compound, (2) primary coupling the tetrazolated with 1-amino-8-naphtol-3,6-disulfonic acid, (3) secondary coupling the primary coupling solution with the diazolated product of aniline compound, (4) finally coupling the secondary coupling solution with benzene-based compound, (5) mixing active carbon or a mixture of active carbon and siliceous earth into the solution (4), and (6) salting out the residual solution (5). In formula, R1 and R2 are H, CH3 or OCH3, R3 is H, SO3H, NO2 or OH, X and Y are H, OH, NH2 or CH3.