Synthesis of polymer with bisstyrylanthracene chromophore on polymer skeleton and application to electroluminescent devices

Novel EL polymer, in which 9,10-bis[4-(N,N-diphenylamino)styryl]anthracene chromophore (polymer-BSA) was synthesized. Two kinds of EL devices were fabricated: One is a single-layer device, ITO/polymer-BSA/MgAg, and the other is a double-layer device, ITO/polymer-BSA/OXD-7/MgAg, in which a vacuum-sublimed 1,3-bis(4-tert-butylphenyl-1,3,4-oxadiazolyl)phenylene (OXD-7) layer plays the roles of electron transport and hole blocking. The quantum efficiency of the double-layer device was observed about 60 times higher than that of the single-layer device. In the double-layer device, the maximum current density of 40 mA/cm(2) was observed at the applied voltage of 23 V and the maximum luminance was about 60 cd/m(2). EL spectra of the single-layer and double-layer devices have peaks at about 595 nm, which coincided with a photoluminescence spectrum of a polymer-BSA film.