Azomethine-Zinc Complexes for Emitting Materials in Organic Electroluminescent Devices

Abstract

Newly synthesized azomethine-zinc complexes were examined as an emitting material in organic electroluminescence (EL) cells. Metal complexes which sublime in vacuum can be used for organic EL cells. Only inner complex salts were found to satisfy this condition. The inner complex salts of the azomethine-zinc complex were prepared by the reaction of zinc ion and ligands such as N-salicylidenealkylamine or N, N'-disalicylidenealkanediamine. A cell structure of [ITO/hole transport layer/emitting layer/Mgln] was employed. The EL cell with (N,N'-disalicylidene-l,6-hexanediaminato)zinc(II) as an emitting layer showed a bright blue emission with an intensity of 1460 cd/m2 for the first time as a complex emitting material. The emission peak was 462 nm. © 1993, The Chemical Society of Japan. All rights reserved.