Patent ID: 7198859

Claim:
A device comprising, an anode; a cathode; a first organic layer disposed between the anode and the cathode, wherein the first organic layer produces phosphorescent emission when a voltage is applied between the anode and the cathode; and an organic enhancement layer disposed between the first organic layer and the cathode, wherein the organic enhancement layer is in physical contact with the first organic layer, and wherein the organic enhancement layer comprises a material having the structure: wherein R 3 –R 10 are substituents, each independently selected from the group consisting of hydrogen, alkyl, alkenyl, alkynyl, alkylaryl, CN, perfluoroalkyl, trifluorovinyl, CO 2 R 1 , C(O)R 1 , NR 1 R 2 , NO 2 , OR 1 , halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl or a heterocyclic group, wherein each of R 1 and R 2 is independently selected from the group consisting of hydrogen, alkyl, alkylaryl and aryl; additionally or alternatively, any one or more of R 7 and R 8 , R 8 and R 9 , or R 9 and R 10 , together form independently a fused aromatic ring; each Z may be the same or different, and is an ancillary ligand; x is a value from 1 to the maximum number of ligands that may be attached to the metal; and x+y is less than or equal to the maximum number of ligands that may be attached to the metal.