Single-step process for the preparation of bis-(acetoacetylamino) benzene disazo pigments

A process for preparing printing inks comprising the step of preparing a disazo pigment of the formula (I) or a mixture of said disazo pigments ##STR5## where D.sup.1 and D.sup.2 are identical or different and each is unsubstituted phenyl or phenyl substituted by from 1 to 3 radicals selected from the group consisting of C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy, phenoxy, halophenoxy, carboxyl, carbalkoxy, acyl, acyloxy, acylamino, N-mono- or N,N-disubstituted carbamoyl, N-mono- or N,N-disubstituted sulfamoyl, sulfo, cyano, halogen, nitro and trifluoromethyl;

• or
• each is an anthraquinone radical which is linked by the 1- or 2-position to the nitrogen atom of the azo bridge and is unsubstituted or substituted by from 1 to 3 radicals selected from the group consisting of halogen, hydroxyl, nitro, C.sub.1 -C.sub.4 -alkyl, carboxyl, acyl, COO-C.sub.1 -C.sub.4 -alkyl, CONH.sub.2, acylamino, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.8 -alkylamino, benzylamino, anilino, C.sub.1 -C.sub.4 -alkylthio and C.sub.1 -C.sub.4 -alkylphenylsulfonylamino;
• or
• each is a radical of an aromatic heterocycle selected from the group consisting of benzimidazole, benzimidazolone, benzimidazolethione, benzoxazole, benzoxazolone, benzothiazole, 2-phenylbenzothiazole, benzothiazolone, indazole, phthalimide, naphthalimide, benzotriazole, quinonline, quinazoline, quinazolinone, phthalazine, phthalazinone, quinoxaline, benzo{c,d,}indolone, benzimidazo{1,2}-pyrimidone, benzo{e}{1,3}oxazinone, dibenzo{a,c}phenazine, quionxalinone, carbazole and indole, said heterocycles being unsubstituted or substituted by from 1 to 3 radicals selected from the group consisting of halogen, amino, (C.sub.1 -C.sub.4 -alkyl, acetamido, carbomethoxyamino, C.sub.1 -C.sub.4 -alkoxy, nitro, hydroxyphenyl, phenyl, sulfo and carboxyl,
• R.sup.1 and R.sup.2 are identical or different and each is hydrogen, halogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.5 -alkoxycarbonyl, nitro, cyano, phenoxy or trifluoromethyl, by azo coupling, which comprises am coupling in an aqueous medium and in the absence of an organic solvent and without a separate after treatment in an organic solvent and adding at the latest immediately prior to the isolation of the disazo pigment at least one nonionic surfactant which has a cloud point in aqueous solution;
• and incorporating said disazo pigment into a printing ink medium.