Abstract: The application relates to an organic electroluminescent device which contains 2,5 diaminoterephthalic acid derivatives of formula 1a as emitter substances in one or several emitter layers in a pure or doped manner. The ring A is a triple unsaturated benzene ring wherein R4? and R8? are equal to zero or ring A is a double unsaturated ring respectively provided with a double bond in the 1,2 position and 4,5-position, and wherein R10 is a nitrile radical —CN or a radical C(?X1)—X2R1; R11 is a nitrile radical —CN or a radical —C(?X3)—X4R5, X1 and X3 are oxygen, sulphur or imino, X2 and X4 are oxygen, sulphur or optionally substituted amino, R1 to R8, R4? and R8? are H, C1–C20-alkyl, aryl, heteroaryl, R4 and R8 can also be halogen, nitro, cyanogen or amino, R2 to R4, R6–R8, R4? and R8? can also be trifluoromethyl or pentafluorophenyl, wherein certain radicals can form a saturated or unsaturated ring.