Patent ID: 9179518
Filing Date: 2015-11-03
Classification: C09K,H01L,H05B,Y02B

Abstract:
1. An organic light emissive device, which comprises: an anode; a cathode; and an organic light emissive region between the anode and the cathode, which region comprises: a layer of blue light electroluminescent organic material which emits light having first CIE co-ordinates by exciton radiative decay, wherein the blue light electroluminescent material comprises a polymer and is not doped with an emissive dopant; and a further layer of longer wavelength electroluminescent organic material which intrinsically emits light having second CIE co-ordinates by exciton radiative decay, wherein the layer of longer wavelength electroluminescent organic material comprises a polymer; and wherein the layers of blue light and longer wavelength materials are selected so that the organic light emissive region emits white light falling within a region having a CIE x coordinate equivalent to that emitted by a black body at 3000-9000K and CIE y coordinate within 0.05 of the CIE y co-ordinate of said light emitted by a black body and wherein each of the electroluminescent materials comprises a solution processible polymer.