Display device

1 . A display device comprising:

an anode;

an organic EL element layer including a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer and an electron injection layer; and

a cathode, wherein

ΔE 2 _LUMO is defined as a potential barrier between the light-emitting layer and a first mixed layer of the electron transport layer and the hole blocking layer,

ΔE 2 _HOMO is defined as a potential barrier between the light-emitting layer and a second mixed layer of the hole transport layer and the electron blocking layer,

each of the ΔE 2 _LUMO and the ΔE 2 _HOMO is 0.1 eV or higher and 0.5 eV or less,

ΔE 1 _LUMO is defined as a potential barrier between the electron injection layer and the first mixed layer of the electron transport layer and the hole blocking layer,

ΔE 1 _HOMO is defined as a potential barrier between the hole injection layer and the second mixed layer of the hole transport layer and the electron blocking layer, and

each of the ΔE 1 _LUMO and the ΔE 1 _HOMO is 0.5 eV or less (ΔE 1 <0.5 eV).

2 . The display device according to claim 1 , wherein

each of the ΔE 1 _LUMO and the ΔE 1 _HOMO is 0.35 eV or less.

3 . The display device according to claim 2 , wherein

the ΔE 1 _LUMO is 0.2 eV or less.

4 . The display device according to claim 1 , wherein

a thickness of the light-emitting layer is 30 nm or more and 40 nm or less.

5 . The display device according to claim 1 , wherein

a thickness of the light-emitting layer is 20 nm or more and 30 nm or less.

6 . The display device according to claim 1 , wherein

the light-emitting layer is formed by co-evaporation.