Process for the preparation of bisazo pigments in halogen-free solvents

A process for the preparation of bisazo pigments of the formula ##STR22## in which R.sub.1 is hydrogen, chlorine or methyl and R.sub.2 and R.sub.3, independently of one another, are chlorine, methyl or nitro, by reaction (A) of 2 mol of an azocarbonyl chloride of the formula ##STR23## in which R.sub.2 and R.sub.3 are as defined above, with 1 mol of a diamine of the formula ##STR24## in which R.sub.1 is as defined above, or of the formula ##STR25## in which A is a group ##STR26## in which R'.sub.1 and R'.sub.2, independently of one another, are chlorine, methyl, trifluoromethyl, unsubstituted or chlorine-, methyl- or methoxy-substituted phenoxy, and R'.sub.3 and R'.sub.4, independently of one another, are chlorine or methyl, by reaction (b) of one mole of a bis(azocarbonyl chloride) of the formula of a bis(azocarbonyl chloride) of the formula ##STR27## in which A is as defined above, with 2 mol of an amine of the formula ##STR28## in which R'.sub.1 and R'.sub.2 are as defined above, which comprises carrying out the reactions (a) or (b) in the presence of 1,2,3-trimethylbenzene or anisole as the solvent.