Bright blue electroluminescence from hole transporting polycarbonate

Bright blue electroluminescence (EL) was observed for the EL cell with a nonconjugated polymer as an emitting layer. The emitting layer was composed of a hole transporting polycarbonate containing styrylamine as a functional repeating unit (SA-PC). SA-PC was soluble in many solvents. It was very easy to form a smooth and dense thin film at a thickness less than 100 nm without any recrystallization. For the EL cell with ITO/SA-PC/an oxadiazole derivative/Mg:Ag structure, we achieved bright luminance of 130 cd/m2 at a current of 80 mA/cm2 with an applied voltage of 11 V.