ORGANIC ELECTROLUMINESCENT ELEMENT, DISPLAY AND LIGHTING DEVICE

1 . An organic electroluminescent element comprising:

a luminescent layer sandwiched between an anode and a cathode, and

a plurality of organic layers including the luminescent layer, wherein

the luminescent layer contains a phosphorescent compound, and host compounds A and B both satisfying the following Equations and Requirement (11).

Host Compound A=X+nR 1

Host Compound B=X+mR 2

(in Equations, X has a structure formed via linking a plurality of aromatic cyclic groups, and represents a structure having the same linking positions; The aromatic cyclic group means an aromatic hydrocarbon cyclic group or an aromatic heterocyclic group;

X of the host compound A has a structure the same as of X of the host compound B;

R 1 represents a hydrogen atom, a phenyl group optionally having a substituent, or an alkyl group optionally having a substituent;

R 2 represents an electron withdrawing group, or a 5-membered or a 6-membered nitrogen-containing heterocyclic group;

“n” represents 0 or an integer of 1˜4, and when “n” is 0, R 1 represents a hydrogen atom; and

“m” represents an integer of 1˜4); and

[HOMO Energy Level of Host Compound A ]−[HOMO Energy Level of Host Compound B ]≥0.15 eV.  (11):

2 . The organic electroluminescent element described in claim 1 , wherein X includes a structures represented by the following General Formulae (2)˜(7).

(In General Formulae (2)˜(4), X 1 and X 2 independently represent any one of an oxygen atom, a sulfur atom and a nitrogen atom; When X 1 and/or X 2 represent a nitrogen atom, X 1 and/or X 2 representing a nitrogen atom have a substituent; and L 1 , L 2 and L 3 represent linkers, respectively);

(In General Formula (5), “Ring a” represents an aromatic ring or a heterocyclic ring both represented by Formula (a5) fused at optional positions of adjacent 2 rings; X 51 represents C—R or a nitrogen atom;

“Ring b” represents a heterocyclic ring represented by Formula (b5) fused at optional positions to adjacent 2 rings;

L 1 and L 2 independently represent a C6˜22 aromatic hydrocarbon cyclic group, a C3˜16 aromatic heterocyclic group or a group thus formed via linkage of the 2˜10 cyclic groups; The aromatic hydrocarbon cyclic group and aromatic heterocyclic group in L 1 and L 2 may have a substituent;

“p” represents an integer of 0˜7. When “p” is 2 or more, L 1 (s) may be the same or different respectively, and L 2 (s) may be the same or different each other; and

R, R 51 ˜R 53 independently represent a hydrogen atom, a C1˜20 alkyl group, a C7˜38 aralkyl group, a C2˜20 alkenyl group, a C2˜20 alkynyl group, a C2˜40 dialkylamino group, a C12˜44 diarylamino group, a C14˜76 diaralkylamino group, a C2˜20 acyl group, a C2˜20 acyloxy group, a C1˜20 alkoxy group, a C2˜20 alkoxycarbonyl group, a C2˜20 alkoxycarbonyloxy group, a C1˜20 alkylsulfonyl group, a C6˜22 aromatic hydrocarbon cyclic group, or a C3˜16 aromatic heterocyclic group, and each of those groups may have a substituent);

(In General Formula (6), A 61 ˜A 68 independently represent C—Rx or a nitrogen atom, and a plurality of Rx(s) may be the same or different each other; The plurality of Rx(s) independently represent a hydrogen atom or the same meaning as the substituent in General Formulae (2)˜(4); and R 61 and R 62 independently represent the same meaning as Rx); and

(In General Formula (7), X 71 , X 72 and X 73 independently represent C—R′ or a nitrogen atom, and at least one of X 71 , X 72 and X 73 is a nitrogen atom; R′, Ar 71 and Ar 72 independently represent a hydrogen atom, a substituted or non-substituted C1˜12 alkyl group, or a substituted or non-substituted C6˜30 aryl group where the number of ring forming carbon atoms is 6˜30, and there is no case that all of R′, Ar 71 and Ar 72 simultaneously represent a hydrogen atom).

3 . The organic electroluminescent element described in claim 1 , wherein R 2 represents an electron withdrawing group, a 5-membered or a 6-membered nitrogen-containing aromatic heterocyclic group.

4 . The organic electroluminescent element described in claim 1 , wherein the host compounds A and B satisfy the following Requirements (12) and (13).

Excited Triplet State Energies of Host Compounds A and B ( T 1 Energies)≥3.0 eV; and  (12):

[LUMO Energy Level of Host Compound A ]−[LUMO Energy Level of Host Compound B ]≥0.15 eV.  (13):

5 . The organic electroluminescent element described in claim 1 , comprising the phosphorescent compound and the host compounds A and B all of which satisfy the following Requirements (14)˜(16).

A luminescence maxim wavelength of luminescence spectrum in a solution of the phosphorescent compound is 470 nm or less;  (14):

[HOMO Energy Level of Phosphorescent Compound]−[HOMO Energy Level of Host Compound B ]≥0.35 eV; and  (15):

A ratio of the host compound A to the host compound B is in the range of 10:90˜90:10.  (16):

6 . A display provided with the organic electroluminescent element described in claim 1 .

7 . A lighting device provided with the organic electroluminescent element described in claim 1 .