Plurality of host materials and organic electroluminescent device comprising the same

A plurality of host materials comprising a first host material comprising a compound represented by the following formula 1, and a second host material comprising a compound represented by the following formula 2:

• wherein
• X1 and Y1 each independently represent —N═, —NR15—, —O—, or —S—, with the proviso that one of X1 and Y1 is —N═, and the other of X1 and Y1 is —NR15—, —O—, or —S—;
• L1 represents a single bond, or a substituted or unsubstituted (C6-C30)arylene;
• Ar1 represents a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, a substituted or unsubstituted mono- or di-(C1-C30)alkylamino, a substituted or unsubstituted mono- or di-(C6-C30)arylamino, a substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamino, or a substituted or unsubstituted (C6-C30)aryl(3- to 30-membered)heteroarylamino;
• R11 represents a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (3- to 30-membered)heteroaryl;
• R12 to R15 each independently represent hydrogen, deuterium, a halogen, a cyano, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, a substituted or unsubstituted (C3-C30)cycloalkyl, a substituted or unsubstituted (C1-C30)alkoxy, a substituted or unsubstituted tri(C1-C30)alkylsilyl, a substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl, a substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl, a substituted or unsubstituted tri(C6-C30)arylsiyl, a substituted or unsubstituted mono- or di-(C1-C30)alkylamino, a substituted or unsubstituted mono- or di-(C6-C30)arylamino, or a substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamino:
• or may be linked to an adjacent substituent to form a ring(s);
• a and b each independently represent 1 or 2, and c is an integer of 1 to 3, where if a to c are an integer of 2 or more, each of R12 to each of R14 may be the same or different;
• wherein
• HAr represents a substituted or unsubstituted (3- to 30-membered)heteroaryl containing a nitrogen atom(s):
• L2 represents a single bond, or a substituted or unsubstituted (C6-C30)arylene;
• and
• R1 to Re each independently represent hydrogen, deuterium, or a (C6-C30)aryl unsubstituted or substituted with deuterium.