abstract |
An object of the present invention is to enable suppression of a leak current of an organic EL element while improving a conductivity of the organic EL element and suppressing an operation voltage thereof. An organic EL element is used which comprises at least a luminescent layer, a hole transport layer adjacent to a positive-electrode side of the luminescent layer, and an electron injection transport layer adjacent to a negative-electrode side of the luminescent layer, wherein a hole injection layer is provided between the hole transport layer and the positive electrode, and the conductivity of the hole injection layer continuously changes along a thickness direction of the hole injection layer. |