Organic electroluminescent material and device made therefrom

摘要

This invention relates to organic electroluminescent elemental devices (organic EL devices) of excellent durability and to organic EL materials useful for such organic EL devices. The organic EL material of this invention comprises a tertiary amine containing 2 to 4 nitrogen atoms each forming a triarylamine wherein the organic electroluminescent material comprises 1 wt.% or less of impurity compounds (A) possessing one less nitrogen atom forming a triarylamine group than said tertiary aryl amine compound and/or 2 wt.% or less of impurity compounds (B) possessing one more nitrogen atom forming a diarylamino group than said tertiary aryl amine compound. The organic electrominescent material can be used in an organic EL device. Some of such tertiary aryl amines are selected from compounds represented by (Ar1Ar2 N-)2-Ar3, (Ar1Ar2N- Ar3-)3-N, (Ar1Ar2N- Ar3-) 2-N-Ar4 and (Ar1Ar2 N-) 4-Ar5 (wherein Ar1, Ar2 and Ar4 are independently monovalent aryl groups, Ar3 is independently a divalent aryl group and Ar5 is a tetravalent aryl group). The organic EL materials of this invention are used, for example, as hole transporting layer in organic EL devices.