Electroluminescent device with polymeric charge injection layer

摘要

An electroluminescent device comprises first and second electrodes, a layer of an electroluminescent polymer disposed between the electrodes; and a hole injection layer disposed between the first electrode and the layer of electro-luminescent polymer. The hole injection layer is formed from a polymer having a main chain and a plurality of sidechains each attached at one of its ends to the main chain, at least some of the sidechains containing an electron-donating substituent such that the oxidation potential of the polymer is less positive than about +1.6 V, and is desirably in the range of about +0.4 to about +0.8 V. Preferred electron-donating groups are di- and triphenylamino groups.