Metal azo pigments

Metal azo pigments comprising:

• a) at least three metal azo compounds which differ at least in the type of metal and which each contain
• structural units of the formula (I), or the tautomeric forms thereof,
• in which
• R1 and R2 are each independently OH, NH2 or NHR5,
• R3 and R4 are each independently ═O or ═NR5,
• R5 is hydrogen or alkyl, and
• Ni2+ and Zn2+ ions and at least one further metal ion Me, where
• Me is a di- or trivalent metal ion selected from the group consisting of La3+, Ce3+, Pr3+, Nd2+, Nd3+, Sm2+, Sm3+, Eu2+, Eu3+, Gd3+, Tb3+, Dy3+, Ho3+, Er3+, Tm3+, Yb2+, Yb3+, Mg2+, Ca2+, Sr2+, Ba2+, Sc3+, Y3+, Ti2+, Ti3+, Zr2+, Zr3+, V2+, V3+, Nb3+, Cr3+, Mo2+, Mo3+, Mn2+, Cd2+and Pb2+,
• with the proviso that the amount of Zn2+ and Ni2+ ions together is 75 to 99.5 mol % and the amount of metal ions Me is 25 to 0.5 mol %, based in each case on one mole of all metal ions in the metal azo pigment, and
• where the molar ratio of Zn2+ to Ni2+ ions in the metal azo pigment is 90:3 to 3:90, and
• b) at least one compound of the formula (II)
• in which R6 is hydrogen or alkyl.