Development of Long Lifetime and High Performance Organic Light Emitting Diode Display with Wide Temperature Range

Abstract

A long lifetime organic light emitting diode (OLED) display at high temperature was developed with optimization of each layer organic materials. We clarified that charge-carrier balance between hole and electron inside the emission layer (EML) affects the lifetime of OLEDs, especially for blue-OLED. We also clarified that the lifetime becomes long with increasing the density of hole in the EML. The lifetimes of the blue-, green, and red-OLEDs developed in this study were achieved over 1,000 hours at 85 ℃ under a driving of 600 cd/m² white luminance. A prototype 12.3 inch flexible OLED display was fabricated with using the new electron-blocking layer, hole-blocking layer, and hole-transport layer materials. We believe that the OLED display that we developed would be useful for automotive application.