Aromatic amine derivative and organic electroluminescence device utilizing the same

An organic electroluminescence device, comprising:

• a cathode;
• an anode;
• and
• an organic thin film layer comprising one or more layers,
• wherein
• the organic thin film layer comprises a light emitting layer,
• the organic thin film layer is interposed between the cathode and the anode,
• the organic thin film layer comprises a hole transporting layer between the anode and the light emitting layer, and
• the hole transporting layer comprises an aromatic amine compound represented by formula (2-a):
• wherein:
• each of Ar20 and Ar21 independently represents a substituted or unsubstituted aryl group having 5 to 40 ring carbon atoms or a substituted or unsubstituted heterocyclic group having 5 to 40 ring atoms, provided that each of Ar20 and Ar21 does not contain a vinyl group;
• each of R41 to R44 independently represents a hydrogen atom, an unsubstituted aryl group having 5 to 50 ring carbon atoms, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 50 carbon atoms, a substituted or unsubstituted aralkyl group having 6 to 50 ring carbon atoms, an unsubstituted aryloxy group having 5 to 50 ring carbon atoms, a substituted or unsubstituted arylthio group having 5 to 50 ring carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 1 to 50 carbon atoms, a substituted or unsubstituted silyl group, a halogen atom, a cyano group, a nitro group, a hydroxyl group, or a carboxyl group;
• a leftmost benzene ring is optionally substituted by 1 to 3 substituents selected from the group consisting of a substituted or unsubstituted aryl group having 5 to 50 ring carbon atoms, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 50 carbon atoms, a substituted or unsubstituted aralkyl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted aryloxy group having 5 to 50 ring carbon atoms, a substituted or unsubstituted arylthio group having 5 to 50 ring carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 1 to 50 carbon atoms, a substituted or unsubstituted silyl group, a halogen atom, a cyano group, a nitro group, a hydroxyl group, and a carboxyl group;
• and
• when the leftmost benzene ring is substituted by 2 or 3 substituents, the 2 or 3 substituents are different from each other.