EFFICIENT BLUE ELECTROLUMINESCENCE FROM A FLUORINATED POLYQUINOLINE

High efficiency blue electroluminescence is demonstrated from a polyqu inoline ether, a new class of soluble, electroluminescent, polyaromati c polymer. Multilayer devices (consisting of hole and electron transpo rt layers in addition to the emissive polyquinoline layer) show an int ernal quantum efficiency in excess of 4% at 450 nm. Light emitted from these devices is easily visible in room light with luminence levels o f 30 cd/m2 at 55 V with a current density of 9 mA/cm2. The transport l ayers are shown to serve a dual function-to modify the carrier injecti on properties and to block passage of carriers of the opposite polarit y thereby trapping carriers in the emissive layer.