An organic electroluminescent device with improved long-term stability is
disclosed, comprising either a dual layer of a layer I and a layer II or
a mixture of the two layers between an EL multilayer and a second
electrode, the layer II being made of at least one alkali metal, alkaline
earth metal, or compound thereof, the layer I being formed of at least
one material selected from those having chemical formula I and chemical
formula II as shown below. ##STR00001##