| abstract |
The application relates to an organic electroluminescent device which contains 2,5 diaminoterephthalic acid derivatives of formula 1 a 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 R 4′ and R 8′ 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 R 10 is a nitrile radical —CN or a radical C(═X 1 )—X 2 R 1 ; R 11 is a nitrile radical —CN or a radical —C(═X 3 )—X 4 R 5 , X 1 and X 3 are oxygen, sulphur or imino, X 2 and X 4 are oxygen, sulphur or optionally substituted amino, R 1 to R 8 , R 4′ and R 8′ are H, C1–C20-alkyl, aryl, heteroaryl, R 4 and R 8 can also be halogen, nitro, cyanogen or amino, R 2 to R 4 , R 6 –R 8 , R 4′ and R 8′ can also be trifluoromethyl or pentafluorophenyl, wherein certain radicals can form a saturated or unsaturated ring. The novel devices are characterized by narrow emission bands, low driver voltages, high photometric efficiency and high thermal stability within a broad spectral range. |