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##
This application is a Divisional of application Ser. No. 09/848,282 filed May 4, 2001 now U.S. Pat. No. 6,663,985 which is further a Continuation of 09/178,515 filed Oct. 26, 1998 now U.S. Pat. No. 6,248,458 whose disclosure therein is incorporated herein by reference.
Priority Data
Nov 17, 1997 [KR] 97-60534 May 20, 1998 [KR] 98-18193 Sep 09, 1998 [KR] 98-37215
