Organic EL element and display device

1. An organic electroluminescent (EL) element, comprising:

a first electrode;

a second electrode;

an interlayer between the first electrode and the second electrode, the interlayer including at least one of a crosslinking group and an insolubilizing group and being formed via coating; and

an organic light-emitting layer between the interlayer and the second electrode, the organic light-emitting layer being a blue light-emitting layer and being formed via coating; wherein:

the organic light-emitting layer contains at least a host material and a dopant material, and a foundation of the organic light-emitting layer includes the interlayer;

the interlayer is formed of a material which has an energy gap larger than an energy gap of the dopant material and a highest occupied molecular orbital (HOMO) level deeper than a HOMO level of the dopant material; and

the interlayer includes arylamine, but does not include fluorene.

2. The organic EL element according to claim 1 ,

wherein the host material and the dopant material are low-molecular materials.

3. The organic EL element according to claim 1 ,

wherein the energy gap of the material used to form the interlayer is larger than an energy gap of the host material.

4. The organic EL element according to claim 3 ,

wherein the energy gap of the material used to form the interlayer is 2.95 eV or more.

5. The organic EL element according to claim 3 ,

wherein the energy gap of the material used to form the interlayer is 3.10 eV or more.

6. The organic EL element according to claim 3 ,

wherein the HOMO level of the material used to form the interlayer is substantially equal to a HOMO level of the host material.

7. The organic EL element according to claim 1 ,

wherein a material of the interlayer has a structural unit which includes arylamine but does not include fluorene, the structural unit being represented by Chemical formula 1, and

in Chemical formula 1, Ar11 to Ar15 each independently represent a same or different substituted or unsubstituted aromatic group, and a represent an integer ranging from 0 to 3.

8. The organic EL element according to claim 1 ,

wherein a material of the interlayer has a structural unit which includes arylamine but does not include fluorene, the structural unit being represented by Chemical formula 2, and

in Chemical formula 2, Ar21 to Ar25 each independently represent a same or different substituted or unsubstituted aromatic group, and b represent an integer ranging from 0 to 3.

9. The organic EL element according to claim 1 ,

wherein a material of the interlayer has a structural unit which includes arylamine but does not include fluorene, the structural unit being represented by Chemical formula 3, and

in Chemical formula 3, Ar31 to Ar36 each independently represent a same or different substituted or unsubstituted aromatic group, and c represent an integer ranging from 0 to 3.

10. The organic EL element according to claim 7 ,

wherein the aromatic group includes a condensed polycyclic structure.

11. The organic EL element according to claim 7 ,

wherein the aromatic group includes a heterocyclic structure.

12. The organic EL element according to claim 7 ,

wherein the organic light-emitting layer is formed using a coating method.

13. A display device comprising the organic EL element according to claim 1 .

14. The organic EL element according to claim 1 , wherein the material of the interlayer is poly-TPD.