Plurality of host materials and organic electroluminescent device comprising the same

A plurality of host materials comprising at least one first host compound and at least one second host compound, wherein the first host compound is represented by the following formula 1, and the second host compound is represented by the following formula 2:

• in formula 1,
• ring A represents
• R1 to R11, each independently, represent hydrogen, deuterium, a halogen, a cyano, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C3-C30)cycloalkyl, a substituted or unsubstituted (3- to 7-membered)heterocycloalkyl, a substituted or unsubstituted fused ring group of a (C3-C30) aliphatic ring(s) and a (C6-C30) aromatic ring(s), a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, 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)arylsilyl, or -L1-N—(Ar1)(Ar2);
• with the proviso that at least one of R1 to R11 represents -L1-N—(Ar1)(Ar2);
• T represents O, S, or Se;
• L1, each independently, represents a single bond, a substituted or unsubstituted (C6-C30)arylene, or a substituted or unsubstituted (3- to 30-membered)heteroarylene;
• Ar1 and Ar2, each independently, represent a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C2-C30)alkenyl, a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (3- to 30-membered)heteroaryl;
• and
• a′ to e′, each independently, represent an integer of 1 to 4, where if a′ to e′ are each an integer of 2 or more, each of R7 to each of R11 may be the same as or different from each other;
• in formula 2,
• Y1 represents O or S;
• R′1 to R′3, 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 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)arylsilyl, 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;
• L4, each independently, represents a single bond, a substituted or unsubstituted (C6-C30)arylene, or a substituted or unsubstituted (3- to 30-membered)heteroarylene;
• Ar4 represents a substituted or unsubstituted (3- to 30-membered)heteroaryl containing a nitrogen(s);
• a and d, each independently, represent an integer of 1 to 3, b represents an integer of 1 or 2, and c represents an integer of 1 to 4;
• where if a to d are each an integer of 2 or more, each of R′1, each of R′2, each of R′3, and each of L4 may be the same as or different from each other;
• with the proviso that when the first host compound comprises a compound in which ring A represents
• and the second host compound comprises a compound represented by the following formula 2′, at least one of R3 to R6, and R9 is -L1-N—(Ar1)(Ar2);
• and
• in formula 2′, Y1, R′1 to R′3, L4, Ar4, and a to d are as defined in claim 2.