Patent ID: 7141312

Claim:
An organic electroluminescent device comprising at least one emitter layer which includes at least one 2,5-diaminoterephthalic acid derivative having formula 20a: wherein R 10 is —CN or —C(═X 1 )—X 2 R 1 ; R 11 is —CN or —C(═X 3 )—X 4 R 5 ; X 1 and X 3 , which are the same or different, are oxygen, sulphur or imino; X 2 and X 4 , which are the same or different, are oxygen, sulphur or substituted or unsubstituted amino; R 1 , R 4 , R 5 and R 8 are the same or different and are hydrogen, C1–C20 alkyl, aryl, heteroaryl, wherein aryl and heteroaryl can be substituted singly or multiply with the same or different radicals di-C1–C3-amino, C1–C10 alkoxy, C1–C4 alkyl, cyano, fluorine, chlorine and bromine as well as phenyl; R 4 and R 8 can also be halogen, nitro, cyano or amino and trifluoromethyl; R 2 and R 3 are members of a 5- or 6-membered ring, forming a saturated or unsaturated heterocycle; R 6 and R 7 are members of a 5- or 6-membered ring, forming a saturated or unsaturated heterocycle; and wherein the following radicals can form a saturated or unsaturated ring X 1 and X 2 , R 4 and X 3 , X 3 and X 4 , R 5 and X 4 , R 8 and X 1 , to which further rings can be fused.