Organic electroluminescent element, display device and illuminating device

1. An organic electroluminescent element comprising a substrate having thereon an electrode and at least one organic layer, wherein at least one of the organic layers is a light-emitting layer containing a phosphorescent compound and a host compound, wherein the host compound is represented by Formula (1):

wherein R 1a represents a dibenzothienyl group; R 1 and R 2 each represent a hydrogen atom or a substituent; n1 is 0 and n2 is an integer of 0 to 4, and the phosphorescent compound is represented by Formula (A),

wherein R 1 represents a substituent; Z represents a group of non-metal elements necessary to form a five- to seven-membered ring; n1 is an integer of 0 to 5; B 1 -B 5 each represent a carbon atom, a nitrogen atom, an oxygen atom or a sulfur atom and at least one of them represents a nitrogen atom; M 1 is an metal of 8-10 group in the periodic table; X 1 and X 2 each represent a carbon atom, a nitrogen atom or an oxygen atom; L 1 is a group of elements forming ligands having coordination number 2 with X 1 and X 2 ; m1 is an integer of 1 to 3; m2 is an integer of 0 to 2; and m1+m2 is 2 or 3 and has a HOMO of from −5.15 to −3.50 eV and a LUMO of from −1.25 to +1.00 eV, and the host compound has a 0-0 band of 460 nm or less in a phosphorescence spectrum and the host compound has a glass transition temperature of 90° C. or more.

2. The organic electroluminescent element of claim 1 , wherein the phosphorescent compound has the HOMO of from −4.80 to −3.50 eV and the LUMO of from −0.80 to +1.00 eV.

3. The organic electroluminescent element of claim 1 , wherein m2 is 0 in the phosphorescent compound represented by Formula(A).

4. The organic electroluminescent element of claim 1 , wherein a nitrogen containing heterocyclic ring formed by B 1 to B 5 is an imidazole ring in the phosphorescent compound represented by Formula (A).

5. The organic electroluminescent element of claim 1 , wherein Formula (A) is further represented by Formula (B),

wherein R 1 , R 2 and R 3 each represent a substituent; Z represents a group of non-metal elements necessary to form a five- to seven-membered ring; n1 is an integer of 0 to 5; M 1 is an metal of 8-10 group in the periodic series; X 1 and X 2 each are a carbon atom, a nitrogen atom or an oxygen atom; L 1 is a group of elements forming ligands having coordination number 2 with X 1 and X 2 ; m1 is an integer of 1 to 3; m2 is an integer of 0 to 2; and m1+m2 is 2 or 3.

6. The organic electroluminescent element of claim 5 , wherein the substituent R 2 in Formula (B) is further represented by Formula (C),

wherein R 4 represents a substituent having a steric parameter (Es value) of −0.5 or less; R 5 represents a substituent; n5 is an integer of 0 to 4; and (*) in Formula represents a bonding position.

7. The organic electroluminescent element of claim 1 , wherein a glass transition temperature of the host compound is 130° C. or more.

8. The organic electroluminescent element of claim 1 , wherein a glass transition point of the host compound is 160° C. or more.

9. The organic electroluminescent element of claim 1 , further comprising an electron inhibition layer.

10. The organic electroluminescent element of claim 1 , emitting white light.

11. A display device comprising the organic electroluminescent element of claim 1 .

12. An illuminating device comprising the organic electroluminescent element of claim 1 .

13. A display device comprising the illuminating device of claim 12 and a liquid crystal element as an indicating means.