Abstract: An organic light emitting device including, in sequence, a first electrode, a first charge transport layer, a second charge transport layer in contact with the first charge transport layer, a light emitting layer in contact with the second charge transport layer, and a second electrode, wherein the first charge transport layer includes a first material and a second material, the second charge transport layer includes the second material and a third material, and the light emitting layer includes the third material and a fourth material.

Abstract: An organic EL element characterized by including a first electrode, a second electrode, and a first light-emitting layer, a second light-emitting layer, and a third light-emitting layer that are disposed between the first electrode and the second electrode, the first light-emitting layer, the second light-emitting layer, and the third light-emitting layer each containing a host material and a light-emitting material, in which the first light-emitting layer is a light-emitting layer that emits red light and green light, the second light-emitting layer is a light-emitting layer that emits blue light, and the third light-emitting layer is a light-emitting layer that emits green light.

Abstract: The present disclosure provides an organic element including an anode, a first layer, a functional layer in contact with the first layer, and a cathode in this order. Energy levels of a first host material and a first dopant material that form the first layer and an organic material that forms the functional layer satisfy specific relations.

Abstract: An organic light-emitting device includes, in sequence, an anode, a first light-emitting layer, a second light-emitting layer, and a cathode, in which the first light-emitting layer contains at least a first host and a first guest that fluoresces, the second light-emitting layer contains at least a second host and a second guest that fluoresces, each of the first light-emitting layer and the second light-emitting layer contains no amine compound, and each of the first host and the second host is a hydrocarbon compound whose carbon atoms are SP2 carbon atoms only and has any of structures represented by formulae [1] to [6]: where A to C are each an anthracene residue, a pyrene residue, a benzanthracene residue, a benzpyrene residue, a phenanthrene residue, or a fluoranthene residue, and each of A to C optionally further contains a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group.

Abstract: A light-emitting device includes a plurality of organic EL elements. Each of the organic EL elements includes a reflection electrode, a hole transport region, an electron-trapping luminescent layer, and a light extraction electrode in this order. The hole transport region has a sheet resistance of 4.0×107 ?/sq.? or more at a current of 0.1 nA/pixel, and the total thickness of the hole transport region and the electron-trapping luminescent layer is equivalent to an optical path length enabling emission from the electron-trapping luminescent layer to be enhanced.

Abstract: An organic light emitting device including, in sequence, a first electrode, a first charge transport layer, a second charge transport layer in contact with the first charge transport layer, a light emitting layer in contact with the second charge transport layer, and a second electrode, wherein the first charge transport layer includes a first material and a second material, the second charge transport layer includes the second material and a third material, and the light emitting layer includes the third material and a fourth material.

Abstract: A layered type organic electroluminescence element including two organic electroluminescence layers disposed between a positive electrode and a negative electrode with an intermediate layer interposed therebetween, wherein the intermediate layer contains an alkali metal compound, a reduced form of the alkali metal compound, and a metal element of group II of the periodic table.

Abstract: An organic light emitting element includes, in sequence, an anode, a first light emitting layer, a second light emitting layer, and a cathode. The first light emitting layer includes a first compound and a first light emitting material. The second light emitting layer includes a second compound and a second light emitting material having an energy gap different from an energy gap of the first light emitting material. The organic light emitting element satisfies relations (a) to (c). LUMO(H1)>LUMO(D1)??(a) LUMO(H2)>LUMO(D2)??(b) LUMO(H2)?LUMO(D2)>LUMO(H1)?LUMO(D1)??(c) Where LUMO (H1), LUMO (D1), LUMO (H2), and LUMO (D2) represent a LUMO level of the first compound, a LUMO level of the first light emitting material, a LUMO level of the second compound, and a LUMO level of the second light emitting material, respectively.

Abstract: A white organic electroluminescent (EL) element including an anode, a cathode, and a light-emitting layer disposed between the anode and the cathode. The light-emitting layer includes a first light-emitting layer and a second light-emitting layer. The first light-emitting layer and the second light-emitting layer each contain a host material and a light-emitting dopant material. The first light-emitting layer contains, as the light-emitting dopant material, a green-light-emitting dopant material and a blue-light-emitting dopant material and is a dual-color light-emitting layer that emits green light and blue light. The second light-emitting layer contains, as the light-emitting dopant material, a red-light-emitting dopant material and a green-light-emitting dopant material and is a dual-color light-emitting layer that emits red light and green light.

Abstract: A light-emitting device includes a plurality of organic EL elements. Each of the organic EL elements includes a reflection electrode, a hole transport region, an electron-trapping luminescent layer, and a light extraction electrode in this order. The hole transport region has a sheet resistance of 4.0×107 ?/sq.? or more at a current of 0.1 nA/pixel, and the total thickness of the hole transport region and the electron-trapping luminescent layer is equivalent to an optical path length enabling emission from the electron-trapping luminescent layer to be enhanced.

Abstract: An organic EL device includes at least an anode, a first light-emitting layer, an intermediate layer, a second light-emitting layer, and a cathode in this order. The intermediate layer is adjacent to the first light-emitting layer and the second light-emitting layer. The first light-emitting layer and the second light-emitting layer can trap electrons. A material constituting the intermediate layer is a hydrocarbon that has a HOMO level equal to or lower than the HOMO level of a host of the first light-emitting layer and that has a high S1 level.

Abstract: A light-emitting device includes a plurality of organic EL elements. Each of the organic EL elements includes a reflection electrode, a hole transport region, an electron-trapping luminescent layer, and a light extraction electrode in this order. The hole transport region has a sheet resistance of 4.0×107 ?/sq. or more at a current of 0.1 nA/pixel, and the total thickness of the hole transport region and the electron-trapping luminescent layer is equivalent to an optical path length enabling emission from the electron-trapping luminescent layer to be enhanced.

Abstract: An organic EL element includes a first electrode, a first luminescent layer, a second luminescent layer, a third luminescent layer, and a second electrode, in this order. The second luminescent layer is in contact with the first luminescent layer and the third luminescent layer. The first luminescent layer contains a red dopant and a first host material. The second luminescent layer contains a blue dopant and a second host material, and the third luminescent layer contains a green dopant and the second host material. The second host material is different from the first host material.

Abstract: An organic EL element characterized by including a first electrode, a second electrode, and a first light-emitting layer, a second light-emitting layer, and a third light-emitting layer that are disposed between the first electrode and the second electrode, the first light-emitting layer, the second light-emitting layer, and the third light-emitting layer each containing a host material and a light-emitting material, in which the first light-emitting layer is a light-emitting layer that emits red light and green light, the second light-emitting layer is a light-emitting layer that emits blue light, and the third light-emitting layer is a light-emitting layer that emits green light.

Abstract: An organic light emitting element includes, in sequence, an anode, a first light emitting layer, a second light emitting layer, and a cathode. The first light emitting layer includes a first compound and a first light emitting material. The second light emitting layer includes a second compound and a second light emitting material having an energy gap different from an energy gap of the first light emitting material. The organic light emitting element satisfies relations (a) to (c). LUMO(H1)>LUMO(D1)??(a) LUMO(H2)>LUMO(D2)??(b) LUMO(H2)?LUMO(D2)>LUMO(H1)?LUMO(D1)??(c) Where LUMO (H1), LUMO (D1), LUMO (H2), and LUMO (D2) represent a LUMO level of the first compound, a LUMO level of the first light emitting material, a LUMO level of the second compound, and a LUMO level of the second light emitting material, respectively.

Abstract: An organic light emitting device including, in sequence, a first electrode, a first charge transport layer, a second charge transport layer in contact with the first charge transport layer, a light emitting layer in contact with the second charge transport layer, and a second electrode, wherein the first charge transport layer includes a first material and a second material, the second charge transport layer includes the second material and a third material, and the light emitting layer includes the third material and a fourth material.

Abstract: A white organic electroluminescent (EL) element includes, in sequence, an anode, a first light-emitting layer that is a blue-light-emitting layer, a hole-blocking layer, an electron transport layer, and a cathode. The hole-blocking layer is adjacent to the first light-emitting layer and the electron transport layer and formed of a hydrocarbon. The electron transport layer is formed of a nitrogen-containing heterocyclic compound. The first light-emitting layer contains a first host and a first dopant that emits blue fluorescent light. Relations (a), (b), and (c) are satisfied. LUMO(H1)>LUMO(D1)??(a) 0.1<d(ETL)/d(HBL)<0.7??(b) 90 nm?d(E)=d(HBL)+d(ETL)<150 nm??(c) LUMO (H1): lowest unoccupied molecular orbital (LUMO) energy of first host LUMO (D1): LUMO energy of first dopant d (HBL): thickness of hole-blocking layer d (ETL): thickness of electron transport layer.

Abstract: A white organic electroluminescent (EL) element including an anode, a cathode, and a light-emitting layer disposed between the anode and the cathode. The light-emitting layer includes a first light-emitting layer and a second light-emitting layer. The first light-emitting layer and the second light-emitting layer each contain a host material and a light-emitting dopant material. The first light-emitting layer contains, as the light-emitting dopant material, a green-light-emitting dopant material and a blue-light-emitting dopant material and is a dual-color light-emitting layer that emits green light and blue light. The second light-emitting layer contains, as the light-emitting dopant material, a red-light-emitting dopant material and a green-light-emitting dopant material and is a dual-color light-emitting layer that emits red light and green light.

Abstract: A white organic electroluminescent (EL) element includes, in sequence, an anode, a first light-emitting layer that is a blue-light-emitting layer, a hole-blocking layer, an electron transport layer, and a cathode. The hole-blocking layer is adjacent to the first light-emitting layer and the electron transport layer and formed of a hydrocarbon. The electron transport layer is formed of a nitrogen-containing heterocyclic compound. The first light-emitting layer contains a first host and a first dopant that emits blue fluorescent light. Relations (a), (b), and (c) are satisfied. LUMO(H1)>LUMO(D1)??(a) 0.1<d(ETL)/d(HBL)<0.

Abstract: An organic EL element includes a first electrode, a first luminescent layer, a second luminescent layer, a third luminescent layer, and a second electrode, in this order. The second luminescent layer is in contact with the first luminescent layer and the third luminescent layer. The first luminescent layer contains a red dopant and a first host material. The second luminescent layer contains a blue dopant and a second host material, and the third luminescent layer contains a green dopant and the second host material. The second host material is different from the first host material.