| abstract |
In a first embodiment of the present invention, in order to increase the number of holes injected into the emissive layer, an intermixed layer is formed from the intermixing of the hole transport layer (“HTL”) and the emissive layer. The intermixed layer is between the HTL and the emissive layer of the OLED device. Alternatively, in a second embodiment of the present invention, in order to increase the number of holes injected into the emissive layer, a separate interlayer is incorporated within the OLED device. The interlayer is comprised of a hole transport material in which one of its components is at least partially replaced with one of the components of the emissive layer that is responsible for hole injection and transport. The separate interlayer is between the anode and the emissive layer of the OLED device. One or more intermediate layers may be present between the interlayer and the anode such as, for example, a HTL may be present between those two layers. |