abstract |
The present invention relates to an organic electroluminescent device comprising a light-emitting layer B containing at least one host compound H of formula (I) wherein not more than two of the residues A 1 , A 2 , A 3 and A 4 are each N, X is O or S, and X′ is NR e , O or S. Further, the present invention refers to a method for generating light of a desired wavelength range by means of an organic electroluminescent device according to the present invention to which an electrical current is applied. |