Organic electroluminescence device

An organic electroluminescence device, comprising in sequential order an anode, an emitting layer, a blocking layer, and a cathode, wherein

• the emitting layer comprises a host and a fluorescent dopant,
• the blocking layer comprises an aromatic heterocyclic derivative,
• a triplet energy ETb (eV) of the aromatic heterocyclic derivative is larger than a triplet energy ETh (eV) of the host,
• the aromatic heterocyclic derivative is represented by formula (BL-4), formula (BL-5) or formula (BL-6);
• wherein in formula (BL-4), D1 to D4 each represent a cyclic structure being fused to form a D1 to D4 ring, at least one of D1 to D4 are structured to have a hetero atom, another fused ring optionally being formed in such a manner as to cross-couple the adjacent Ds in the D1 to D4 ring;
• R represents a group selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heteroaryl group, or residues of combination of two or more thereof;
• when n is 1, R′ represents the same as R,
• when n is 2 to 6, R′ represents a linking group selected from a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, and a substituted or unsubstituted heteroarylene group, and residues of combination of two or more thereof, or
• R′ directly bonds two D1 to D4 rings in a single bond;
• m is an integer of 0 to 11;
• n is an integer of 1 to 5;
• and
• when a plurality of D1 to D4 rings and Rs are present, the plurality of D1 to D4 rings and Rs are each the same or different,
• wherein in the formula (BL-5), E1 to E4 each represent a cyclic structure being fused to form a E1 to E4 ring, at least one of E1 to E4 being structured to have a hetero atom, another fused ring optionally being formed in such a manner as to cross-couple the adjacent substituents on each of E1 to E4 in the E1 to E4 ring;
• R represents a group selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heteroaryl group, or residues of combination of two or more thereof;
• R′ represents the same as R when n is 1,
• R′ represents a linking group selected from a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, a substituted or unsubstituted heteroarylene group, and residues of combination of two or more thereof when n is 2 to 6, or
• R′ directly bonds two E1 to E4 rings in a single bond;
• (m+1) is an integer of 0 to 11;
• n is an integer of 1 to 5;
• and
• when a plurality of E1 to E4 rings and Rs are present, the plurality of E1 to E4 rings and Rs each are the same or different,
• wherein in the formula (BL-6) F1 to F5 each represent a cyclic structure being fused to form a F1 to F5 ring, at least one of F1 to F5 being structured to have a hetero atom, another fused ring optionally being formed in such a manner as to cross-couple adjacent substituents on each of F1 to F5 in the F1 to F5 ring;
• R represents a group selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heteroaryl group, or residues of combination of two or more thereof;
• R′ represents the same as R when n is 1,
• R′ represents a linking group selected from a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, and a substituted or unsubstituted heteroarylene group, and residues of combination of two or more thereof when n is 2 to 6, or
• R′ directly bonds two F1 to F5 rings in a single bond;
• m is an integer of 0 to 13;
• n is an integer of 1 to 5;
• when a plurality of F1 to F5 rings and Rs are present, the plurality of F1 to F5 rings and Rs each are the same or different.