Patent ID: 7701131

Claim:
An organic electroluminescent device, comprising: cathode; anode; at least two mutually delimited emission layers, said emission layers emitting different light wavelengths, wherein at least one emission layer further includes at least one phosphorescent emitter and a matrix material represented by the following formula wherein: X is 0; R 1 , R 2 is the same or different at each instance and is an aromatic or heteroaromatic system having from 1 to 40 carbon atoms, in which one or more hydrogen atoms may be replaced by F, CI, Br, I, and which may be substituted by one or more R radicals, and a plurality of substituents R 1 and/or R 1 , R 2 , either on the same ring or on the two different rings, may together in turn form a further mono- or polycyclic, aliphatic or aromatic ring system; with the proviso that R1=R2 and is not hydrogen; R is the same or different at each instance and is H, CN, a straight-chain, branched or cyclic alkyl, alkoxy or alkylamino group having from 1 to 40 carbon atoms, in which one or more nonadjacent CH 2 groups may be replaced by —R 4 C═CR 4 —, C═O, C═S, C═Se, C═NR 4 , —O—, —S—, —NR 5 — or —CONR 6 —, and in which one or more hydrogen atoms may be replaced by F, CI, Br, I; R 4 , R 5 , R 6 are the same or different at each instance and are H or an aliphatic or aromatic hydrocarbon radical having from 1 to 20 carbon atoms.