Patent ID: 8883323

Claim:
An organic electroluminescence device, comprising in sequential order an anode, an emitting layer, a blocking layer, an electron injecting layer, and a cathode, wherein the emitting layer comprises a host and a dopant, the blocking layer comprises an aromatic heterocyclic derivative, a triplet energy E T b (eV) of the aromatic heterocyclic derivative is larger than a triplet energy E T h (eV) of the host, the triplet energy E T h (eV) of the host and a triplet energy E T d (eV) of the dopant satisfy E T h <E T d , and an affinity A b (eV) of the blocking layer and an affinity A e (eV) of the electron injecting layer satisfy a relationship of A e −A b <0.2, wherein the aromatic heterocyclic derivative is represented by formula (BL-6) wherein F 1 to F 5 each independently represent a cyclic structure and a F 1 -F 5 ring represents a fused ring provided by F 1 to F 5 , optionally cross-coupled by another fused ring, at least one of F 1 to F 5 comprises a hetero atom, R is independently selected from the group consisting of a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, and a combination thereof, when a plurality of F 1 -F 5 rings and R groups are present, the plurality of F 1 -F 5 rings and the R groups each may be the same or different, m is an integer of 0 to 13, n is an integer of 1 to 6, when n is 1, R′ is independently selected from the group consisting of a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, and a combination thereof, when n is 2 to 6, R′ is a linking group independently selected from the group consisting of a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, a substituted or unsubstituted heteroarylene group, and a combination thereof, or R′ is a single bond that directly bonds two F 1 -F 5 rings.