METHOD OF MAKING YELLOW PIGMENT FOR PRINTING INK

摘要

To prepare the yellow pigment of formula (I) where R denotes the phenyl or naphthyl radical, unsubstituted or substituted a number of times by alkyl, alkoxy or halogen, one mole of 4,4'-diamino-3,3'-dichlorodiphenyl is coupled in acidic medium with 2 moles of acetoacetarylide of formula (II> CH3-CO-CH2-CO-NH-R (II), where R has the meaning indicated above, in the presence of a water-soluble zirconium or aluminium salt. The pigment of formula (I) is employed in the preparation of printing inks.