ORGANIC ELECTROLUMINESCENT ELEMENT

1 - 12 . (canceled)

13 . An organic electroluminescent device, comprising one or more light-emitting layers between an anode and a cathode opposite to each other, wherein: at least one of the light-emitting layers contains at least two kinds of host materials and at least one kind of light-emitting dopant; and at least one kind of the host materials comprises a host material (H1) selected from compounds each represented by any one of the following general formulae (1) and (2), and at least one kind of the host materials comprises a host material (H2) selected from compounds each represented by the following general formula (3):

wherein:

a ring a represents an aromatic ring or a heterocycle represented by the formula (a1) that is fused at arbitrary positions of two adjacent rings, X 1 represents C—R or N, a ring b represents a heterocycle represented by the formula (b1) that is fused at arbitrary positions of two adjacent rings, Ar 1 and Ar 2 each independently represent an aromatic hydrocarbon group having 6 to 24 carbon atoms, or an aromatic heterocyclic group having 3 to 16 carbon atoms, L 1 represents an aromatic hydrocarbon group having 6 to 24 carbon atoms, an aromatic heterocyclic group having 3 to 16 carbon atoms, or a linked aromatic group obtained by linking 2 to 10 aromatic rings of the groups, and the aromatic hydrocarbon group, the aromatic heterocyclic group, or the linked aromatic group in Ar 1 , Ar 2 , and L 1 may have a substituent;

p represents an integer of from 0 to 7, provided that when p represents 2 or more, L 1 's may be identical to or different from each other; and

R and R 1 to R 3 each independently represent hydrogen, an alkyl group having 1 to 20 carbon atoms, an aralkyl group having 7 to 38 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, a dialkylamino group having 2 to 40 carbon atoms, a diarylamino group having 12 to 44 carbon atoms, a diaralkylamino group having 14 to 76 carbon atoms, an acyl group having 2 to 20 carbon atoms, an acyloxy group having 2 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkoxycarbonyl group having 2 to 20 carbon atoms, an alkoxycarbonyloxy group having 2 to 20 carbon atoms, an alkylsulfonyl group having 1 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 24 carbon atoms, or an aromatic heterocyclic group having 3 to 16 carbon atoms, and may each have a substituent;

wherein:

a ring c and a ring c′ each represent an aromatic ring or a heterocycle represented by the formula (c1) that is fused at arbitrary positions of adjacent rings, a ring d and a ring d′ each represent a heterocycle represented by the formula (d1) that is fused at arbitrary positions of adjacent rings, and the ring c and the ring c′, or the ring d and the ring d′ may be identical to or different from each other;

X 2 represents C—R′ or N, Z represents an aromatic hydrocarbon group having 6 to 24 carbon atoms, an aromatic heterocyclic group having 3 to 16 carbon atoms, or a divalent linked aromatic group obtained by linking 2 to 10 aromatic rings of the groups, Ar 3 represents an aromatic hydrocarbon group having 6 to 24 carbon atoms, or a monocyclic aromatic heterocyclic group having 3 to 6 carbon atoms, L 2 represents an aromatic hydrocarbon group having 6 to 24 carbon atoms, an aromatic heterocyclic group having 3 to 18 carbon atoms, or a linked aromatic group obtained by linking 2 to 10 aromatic rings of the groups, and the aromatic hydrocarbon group, the aromatic heterocyclic group, or the linked aromatic group in Z, Ar 3 , and L 2 may have a substituent;

q represents an integer of from 0 to 7, provided that when q represents 2 or more, L 2 's may be identical to or different from each other; and

R′ and R 4 to R 8 each independently represent hydrogen, an alkyl group having 1 to 20 carbon atoms, an aralkyl group having 7 to 38 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, a dialkylamino group having 2 to 40 carbon atoms, a diarylamino group having 12 to 44 carbon atoms, a diaralkylamino group having 14 to 76 carbon atoms, an acyl group having 2 to 20 carbon atoms, an acyloxy group having 2 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkoxycarbonyl group having 2 to 20 carbon atoms, an alkoxycarbonyloxy group having 2 to 20 carbon atoms, an alkylsulfonyl group having 1 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 24 carbon atoms, or an aromatic heterocyclic group having 3 to 16 carbon atoms, and may each have a substituent;

wherein:

R 9 to R 12 each independently represent an aromatic hydrocarbon group having 6 to 18 carbon atoms or an aromatic heterocyclic group having 3 to 9 carbon atoms, and may each have a substituent;

Ar 4 's each independently represent hydrogen or an aromatic hydrocarbon group having 6 to 24 carbon atoms, and the aromatic hydrocarbon group may have a substituent, j represents an integer of from 1 to 6, and at least one Ar 4 does not represent hydrogen;

X 3 to X 5 each independently represent N, C—R″, or C—, and R″'s each independently represent hydrogen, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or a diarylamino group having 12 to 44 carbon atoms; and

k, l, m, and n represent integers satisfying 0≤k+1+m+n≤16,

provided that the following formula (III-7) is excluded from the general formula (3).

14 . An organic electroluminescent device according to claim 13 , wherein one of the two host materials comprises a host material selected from the compounds each represented by any one of the general formulae (1) and (2), another one of the two host materials comprises a host material selected from the compounds each represented by the general formula (3), and a difference in electron affinity (ΔEA) between the two host materials is more than 0.1 eV.

15 . An organic electroluminescent device according to claim 13 , wherein in the general formula (1), X 1 represents C—R.

16 . An organic electroluminescent device according to claim 13 , wherein in the general formula (2), X 2 represents C—R′.

17 . An organic electroluminescent device according to claim 13 , wherein in the general formula (1), at least one of Ar 1 or Ar 2 represents a substituted or unsubstituted aromatic heterocyclic group having 3 to 9 carbon atoms.

18 . An organic electroluminescent device according to claim 13 , wherein in the general formula (3), j represents an integer of 1.

19 . An organic electroluminescent device according to claim 13 , wherein in the general formula (3), X 3 to X 5 each represent C—H, N, or C—.

20 . An organic electroluminescent device according to claim 13 , wherein the organic electroluminescent device comprises a light-emitting layer produced by preliminarily mixing the host material (H1) and the host material (H2), and vapor-depositing the mixture from one vapor deposition source.

21 . An organic electroluminescent device according to claim 20 , wherein a presence ratio of each of the host material (H1) and the host material (H2) in the light-emitting layer changes by an amount within 5% relative to a preliminary mixing ratio of each of the host materials before the vapor deposition.

22 . An organic electroluminescent device according to claim 13 , wherein a difference in vaporization temperature between the host material (H1) and the host material (H2) is within 30° C.

23 . An organic electroluminescent device according to claim 22 , wherein the difference in vaporization temperature is within 10° C.

24 . An organic electroluminescent device according to claim 13 , wherein the light-emitting dopant comprises a phosphorescent light-emitting dopant comprising an organometallic complex containing at least one metal selected from ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum, and gold.