Patent number: 6596446
Abstract: The invention relates to pigment preparations comprising a metal complex of a mono-, di-, tri-, or tetraanion of an azo compound that in its free acid form conforms to formula (I) or a tautomeric form thereof
wherein
R and R′ are independently OH, NH2, NH—CN, acylamino, or arylamino, and
R1 and R1′ are independently —OH or —NH2,
with a metal selected from the group consisting of Na, K, Ca, Sr, Ba, Zn, Fe, Ni, Cu, Mn, La, Li, Cs, Mg, Cd, Co, Al, Cr, Sn, and Pb,
wherein the metal complex hosts at least one guest compound.
Type:
Grant
Filed:
April 3, 2001
Date of Patent:
July 22, 2003
Assignee:
Bayer Aktiengesellschaft
Inventors:
Mickey Wolf, Rolf Richter, Kent Faubion, Udo Herrmann, Josef Witt, Peter-Roger Nyssen
