BLUE ORGANIC LIGHT-EMITTING DEVICE USING AROMATIC POLYIMIDE AND PROCESS OF PREPARATION THEREOF

摘要

PURPOSE: A blue colored organo electrical light emitting diode is provided for having good stability and long working time by assembling the diode together with positive electrode, light emitting layer and including aromatic polyimide compound within the light emitting layer. CONSTITUTION: The blue colored organo electrical light emitting diode(LED) having favorable stability and extended working time comprises a positive electrode, LED compound layer and negative electrode. The LED layer contains polyimide compound having the repeating unit of formula 1 (wherein R represents at least one of formulas). The LED layer is obtained by reacting di-anhydride and 9,9-bis(4-aminophenyl)fluorene (9,9-bis (4-aminophenyl)(fluorene, BAF) in organic solvent at a relative mole ratio of 1:1 and under nitrogen atmosphere to form polyamic acid; and coating the polyamic acid over surface of the substrate plate then heating it to form polyimide thin film having the repeating unit of formula 1.