Red electroluminescent devices utilizing dye-dispersed soluble polyimide thin film as an emission layer

The dye-dispersed polymer electroluminescent device using the soluble poly(ether imide) (PEI) of relatively high glass transition temperature was successfully prepared. 4-(Dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran(DCM) was used as a lumophore. The device was turned on at around 12 V. and the brightness at 20 V was very strong. The color of the emitted light was red, which is almost the color of the dispersed dye alone. The stability of the device was also found to be good, even after packaging the cathode side with a polymeric glue at 110 °C.