Disclosed are a novel organic compound, and an organic electroluminescent element having improved characteristics, such as luminous efficiency, driving voltage, and lifespan, by containing the novel organic compound in one or more organic material layers.

The present disclosure relates to an organic compound having the following structure, and an organic light emitting diode (OLED) and an organic light emitting device including the organic compound. The organic compound is a bipolar compound having a p-type moiety and an n-type moiety and has high energy level and proper energy bandgap for an emissive layer of the OLED. As the organic compound is applied into the emissive layer, the OLED can maximize its luminous properties as holes and electrons are recombined uniformly over the whole area in an EML. ##STR00001##

A reliable light-emitting element with low driving voltage is provided. The light-emitting element includes an electron-injection layer between a cathode and a light-emitting layer. The electron-injection layer is a mixed film of a transition metal and an organic compound having an unshared electron pair. An atom of the transition metal and the organic compound form SOMO.

The present disclosure relates to an organic compound having the following structure of Chemical Formula 1, and an organic light emitting diode (OLED) and an organic light emitting device including the organic compound. The organic compound is a bipolar organic compound having a p-type moiety and an n-type moiety. The organic compound has a high excited triplet energy level, a wide energy bandgap and excellent thermal stability. When the organic compound is introduced into an emitting material layer (EML) of the OLED, holes and electrons are recombined in the whole area of the EML, thus the OLED can improve its luminous efficiency and luminous lifetime. ##STR00001##

A light-emitting element which uses a plurality of kinds of light-emitting dopants emitting light in a balanced manner and has high emission efficiency is provided. Further, a light-emitting device, a display device, an electronic device, and a lighting device each having reduced power consumption by using the above light-emitting element are provided. A light-emitting element which includes a plurality of light-emitting layers including different phosphorescent materials is provided. In the light-emitting element, the light-emitting layer which includes a light-emitting material emitting light with a long wavelength includes two kinds of carrier-transport compounds having properties of transporting carriers with different polarities. Further, in the light-emitting element, the triplet excitation energy of a host material included in the light-emitting layer emitting light with a short wavelength is higher than the triplet excitation energy of at least one of the carrier-transport compounds.

A novel light-emitting device is provided. Alternatively, a light-emitting device having a long driving lifetime at high temperature is provided. The light-emitting device includes an anode, a cathode, and an EL layer positioned between the anode and the cathode. The EL layer includes a first layer, a second layer, a third layer, and a light-emitting layer in this order from the anode side. The first layer includes a first organic compound and a second organic compound. The second layer includes a third organic compound. The third layer includes a fourth organic compound. The light-emitting layer includes a fifth organic compound and an emission center substance. The first organic compound exhibits an electron-accepting property with respect to the second organic compound. A difference between HOMO levels of the fourth organic compound and the fifth organic compound is less than or equal to 0.24 eV.

A copolymer including a structural unit represented by Chemical Formula 1 ##STR00001##
wherein the copolymer is capable of improving luminous efficiency and durability, particularly, an improvement in luminescence life-span, of an electroluminescence device, particularly a quantum dot electroluminescence device.

Organic luminescent material, includes: host material, TADF sensitizer, and fluorescent-luminescent material; wherein absolute value of difference between LUMO level of the host material and LUMO level of the TADF sensitizer is not more than 0.4 eV, and absolute-value of difference between HOMO level of the host material and HOMO level of the TADF sensitizer is not more than 0.4 eV; absolute-value of LUMO level of the fluorescent-luminescent material is not more than absolute-value of the LUMO level of the host material and the LUMO level of the TADF sensitizer, and/or absolute-value of HOMO level of the fluorescent-luminescent material is not less than an absolute-value of the HOMO level of the host material and absolute-value of the HOMO level of the TADF sensitizer; and emission-spectrum of the host material overlaps an absorption-spectrum of the TADF sensitizer, and emission-spectrum of the TADF sensitizer overlaps absorption-spectrum of the fluorescent-luminescent material.

Provided is a light-emitting device including an organic light-emitting element and a control unit that controls the organic light-emitting element. The organic light-emitting element includes a first electrode, a second electrode, and an organic light-emitting layer which is disposed between the first electrode and the second electrode and in which separation of charges occurs due to incidence of excited light. The control unit changes a potential difference between the first electrode and the second electrode so that recoupling of the charges occurs, in a second period after passage of a delay period from a first period in which the excited light is incident to the organic light-emitting layer.

A quantum dot light-emitting device including first electrode and a second electrode, a quantum dot layer between the first electrode and the second electrode, a first electron transport layer and a second electron layer disposed between the quantum dot layer and the second electrode. The second electron transport layer is disposed between the quantum dot layer and the first electron transport layer, wherein each of the first electron transport layer and the second electron transport layer includes an inorganic material. A lowest unoccupied molecular orbital energy level of the second electron transport layer is shallower than a lowest unoccupied molecular orbital energy level of the first electron transport layer, and a lowest unoccupied molecular orbital energy level of the quantum dot layer is shallower than a lowest unoccupied molecular orbital energy level of the second electron transport layer. An electronic device including the quantum dot light-emitting device.