High performance polymer-based organic light emitting diodes (OLED) consisting of covalently bonded layers

Polymer-based multi-layered organic light emitting diodes (OLED) were prepared though surface-initiated living radical polymerization. Hole-transport, luminescence, and electron-transport layers were fabricated on an ITO substrate by block copolymerization from the ITO substrate. Since the roles of hole-transportation, luminescence, and electron-transportation are separated in the three layers, the multi-layered OLED exhibited more effective luminescence than a single-layered OLED consisting only of the luminescence layer. This clearly demonstrates the importance of the multi-layered structure for polymer-based OLED, and hence the usefulness of the present concept enabling the preparation of multi-layered polymer-based OLED.