Sharp Kabushiki Kaisha Corporation

Fuji Electric Holdings Co., Ltd.

Yutaka Terao

Koji Kawaguchi

Naoyuki Kanai

Toshio Hama

A method of manufacturing an organic EL element, which may be a top-emitting or a transparent organic EL element, provides an organic EL element having a low driving voltage and a high efficiency. The organic EL element includes a substrate; an anode; an organic EL layer which includes at least an emissive layer, an electron transport layer and a damage-mitigating electron injection layer; and a transparent cathode composed of a transparent conductive oxide material, the damage-mitigating electron injection layer is in contact with the transparent cathode, and the damage-mitigating electron injection layer includes a crystalline oligothiophene compound.

Organic electroluminescent element and method of manufacturing the same

An organic light emitting element includes a pair of electrodes at least one of which has visible light transmittance; and an organic EL layer provided between the pair of electrodes. The organic EL layer includes at least an organic light emitting layer that emits light when a voltage is applied between the pair of electrodes. The organic light emitting layer includes an electron transport host material; and at least first and second guest materials. Each of the first and second guest materials has an emission peak in a blue to blue-green color region. The electron transport host material has an ionization potential (IPH) and an electron affinity (AFH), and the first guest material has an ionization potential (IPG1) and an electron affinity (AFG1) that satisfy Expression (1): IPH&#x2266;IPG1 and AFH&#x3c;AFG1 (1). The organic light emitting element has significantly improved efficiency without any influence on driving voltage.

Organic light emitting element

The object of the present invention is to provide an organic EL device having a structure that resolves a problem of trade-off between decrease in a drive voltage and increase in production yield. The organic EL device of the present invention includes a substrate, a pair of electrodes provided on the substrate, and an organic EL layer sandwiched by the pair of electrodes; the pair of electrodes includes a positive electrode and a negative electrode; the organic EL layer includes at least a light-emitting layer and a hole injection layer that is in contact with the positive electrode; the hole injection layer is formed of an n-type semiconductor host material and a p-type semiconductor guest material; a LUMO level Eof the host material and a HOMO level of the guest material or a valence band level Esatisfy:||+0.5 eV&#x2267;|&#x2212;0.6 eV.

Organic EL device

An organic EL device is provided with a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer and an electron injection layer between an anode and a cathode, wherein the hole injection layer is obtained by doping a hole transport material with an electron-accepting impurity, and the ionization potential Ip(HIL) of the material of the hole injection layer that composes the hole injection layer (also referred to as a hole injection material in the present description), the ionization potential Ip(HTL) of the hole transport material, and the ionization potential Ip(EML) of the material of the light-emitting layer (also referred to as a light-emitting layer material in the present description) respectively satisfy the relationship of Ip(EML)&#x3e;Ip(HTL)&#x2267;Ip(HIL)&#x2267;Ip(EML)&#x2212;0.4 eV.

Organic electroluminescent device

A resonant cavity color conversion EL element in which intensity of converted light from a color conversion layer is increased and an organic EL display device in which viewing angle dependence of the color tone is small and the manufacturing process is simple. The EL element includes at least a pair of electrodes; a functional layer includes a light-emitting layer and is sandwiched by the pair of electrodes; a color conversion layer that absorbs light emitted from the light-emitting layer and emits light with a different wavelength; and a pair of light reflective layers. Notably, the pair of light reflective layers are composed of a non-transparent reflective layer and a semi-transparent reflective layer that have a distance therebetween that is set at an optical distance to construct a microcavity that increases intensity of light with a specific wavelength emitted from the color conversion layer.

Growing community of inventors

Matsumoto, Japan

Yutaka Terao