US Patent 7396598 Light emitting material and organic light-emitting device

A polymer light emitting material, wherein the material has a light emitting mechanism based on transition from an excited triplet state to a ground state or transition through an excited triplet state to a ground state of an electron energy level, and the material comprises a nonionic light emitting part which constitutes a part of the polymer or is bound to the polymer. The polymer light emitting material exhibits high light emission efficiency above 5%, which is the limit of external quantum efficiency of fluorescence and can be designed so as to have a large area and hence are suitable for mass production of organic light emitting devices.