Abstract: A light-emitting element having high emission efficiency is provided. A light-emitting element having a low driving voltage is provided. A novel compound which can be used for a transport layer or as a host material or a light-emitting material of a light-emitting element is provided. A novel compound with a benzofuropyrimidine skeleton is provided. Also provided is a light-emitting element which includes the compound with the benzofuropyrimidine skeleton between a pair of electrodes.

Abstract: A novel light-emitting device is provided. A light-emitting device with high emission efficiency is provided. A light-emitting device with along lifetime is provided. A light-emitting device with low driving voltage is provided. The light-emitting device includes an anode, a cathode, and an EL layer between the anode and the cathode. The EL layer includes a hole-injection layer, a light-emitting layer, and an electron-transport layer. The hole-injection layer is positioned between the anode and the light-emitting layer. The electron-transport layer is positioned between the light-emitting layer and the cathode. The hole-injection layer contains a first substance and a second substance. The first substance is an organic compound which has a hole-transport property and a HOMO level higher than or equal to ?5.7 eV and lower than or equal to ?5.4 eV. The second substance exhibits an electron-accepting property with respect to the first substance.

Abstract: A multicolor light-emitting element using fluorescence and phosphorescence, which has a small number of manufacturing steps owing to a relatively small number of layers to be formed and is advantageous for practical application can be provided. In addition, a multicolor light-emitting element using fluorescence and phosphorescence, which has favorable emission efficiency is provided. A light-emitting element which includes a light-emitting layer having a stacked-layer structure of a first light-emitting layer exhibiting light emission from a first exciplex and a second light-emitting layer exhibiting phosphorescence is provided.

Abstract: A light-emitting layer, which is a stack of a first light-emitting layer and a second light-emitting layer, is provided between an anode and a cathode. The first light-emitting layer is formed on the anode side and contains a first light-emitting substance converting triplet excitation energy into light emission, a first organic compound having an electron-transport property, and a second organic compound having a hole-transport property. The second light-emitting layer contains a second light-emitting substance converting triplet excitation energy into light emission, the first organic compound, and a third organic compound having a hole-transport property. The second organic compound has a lower HOMO level than the third organic compound. The first light-emitting substance emits light with a wavelength shorter than that of light emitted from the second light-emitting substance. The first and the second organic compounds form an exciplex. The first and the third organic compounds form an exciplex.

Abstract: Provided is a light-emitting element with high emission efficiency. The light-emitting element including a first electrode, a second electrode, and a layer containing an organic compound between the first electrode and the second electrode. The layer containing the organic compound includes a light-emitting layer at least containing a first organic compound, a second organic compound, and a fluorescent substance. The first organic compound has an electron-transport property. The second organic compound has a hole-transport property. The second organic compound has a triarylamine skeleton. At least one of three aryl groups in the triarylamine skeleton is a group including a p-biphenyl skeleton.

Abstract: A light-emitting layer, which is a stack of a first light-emitting layer and a second light-emitting layer, is provided between an anode and a cathode. The first light-emitting layer is formed on the anode side and contains a first light-emitting substance converting triplet excitation energy into light emission, a first organic compound having an electron-transport property, and a second organic compound having a hole-transport property. The second light-emitting layer contains a second light-emitting substance converting triplet excitation energy into light emission, the first organic compound, and a third organic compound having a hole-transport property. The second organic compound has a lower HOMO level than the third organic compound. The first light-emitting substance emits light with a wavelength shorter than that of light emitted from the second light-emitting substance. The first and the second organic compounds form an exciplex. The first and the third organic compounds form an exciplex.

Abstract: A novel heterocyclic compound is provided. In particular, a novel heterocyclic compound which can improve the element characteristics of the light-emitting element is provided. The heterocyclic compound is represented by a general formula (G1) DBqAr1nAr2-A??(G1) in which a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group and a substituted or unsubstituted benzobisbenzofuranyl group are bonded to each other via a substituted or unsubstituted arylene group. In the general formula (G1), DBq represents a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group, Ar1 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, Ar2 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, and A represents a substituted or unsubstituted benzobisbenzofuranyl group. When the arylene group represented by Ar1 and Ar2 has substituents, the substituents may be bonded to each other to form a ring.

Abstract: As a novel substance having a novel skeleton, an organometallic complex with high emission efficiency which achieves improved color purity by a reduction of half width of an emission spectrum is provided. One embodiment of the present invention is an organometallic complex in which a ?-diketone and a six-membered heteroaromatic ring including two or more nitrogen atoms inclusive of a nitrogen atom that is a coordinating atom are ligands. In General Formula (G1), X represents a substituted or unsubstituted six-membered heteroaromatic ring including two or more nitrogen atoms inclusive of a nitrogen atom that is a coordinating atom. Further, R1 to R4 each represent a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms.

Abstract: Provided is a novel heterocyclic compound, a novel heterocyclic compound that can be used in a light-emitting element, or a highly reliable light-emitting device, electronic device, and lighting device in each of which the light-emitting element using the novel heterocyclic compound is used. One embodiment of the present invention is a heterocyclic compound represented by General Formula (G1). In General Formula (G1), each of A1 and A2 independently represents nitrogen or carbon bonded to hydrogen, and at least one of A1 and A2 represents nitrogen; Ar represents a substituted or unsubstituted arylene group having 6 to 18 carbon atoms; B represents a substituted or unsubstituted fluorenyl group; and R1 represents hydrogen, an alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 13 carbon atoms.

Abstract: To provide a light-emitting element which uses a fluorescent material as a light-emitting substance and has higher luminous efficiency. To provide a light-emitting element which includes a mixture of a thermally activated delayed fluorescent substance and a fluorescent material. By making the emission spectrum of the thermally activated delayed fluorescent substance overlap with an absorption band on the longest wavelength side in absorption by the fluorescent material in an S1 level of the fluorescent material, energy at an S1 level of the thermally activated delayed fluorescent substance can be transferred to the S1 of the fluorescent material. Alternatively, it is also possible that the S1 of the thermally activated delayed fluorescent substance is generated from part of the energy of a T1 level of the thermally activated delayed fluorescent substance, and is transferred to the S1 of the fluorescent material.

Abstract: A light-emitting element which has low driving voltage and high emission efficiency is provided. The light-emitting element includes, between a pair of electrodes, a hole-transport layer and a light-emitting layer over the hole-transport layer. The light-emitting layer contains a first organic compound having an electron-transport property, a second organic compound having a hole-transport property, and a light-emitting third organic compound converting triplet excitation energy into light emission. A combination of the first organic compound and the second organic compound forms an exciplex. The hole-transport layer contains at least a fourth organic compound whose HOMO level is lower than or equal to that of the second organic compound and a fifth organic compound whose HOMO level is higher than that of the second organic compound.

Abstract: A light-emitting element having high emission efficiency is provided. A light-emitting element having a low driving voltage is provided. A novel compound which can be used for a transport layer or as a host material or a light-emitting material of a light-emitting element is provided. A novel compound with a benzofuropyrimidine skeleton is provided. Also provided is a light-emitting element which includes the compound with the benzofuropyrimidine skeleton between a pair of electrodes.

Abstract: A light-emitting element with a light-emitting substance comprising an organometallic complex. The organometallic complex having a structure represented by General Formula (G0). In the formula, X represents a substituted or unsubstituted six-membered heteroaromatic ring including two or more nitrogen atoms inclusive of a nitrogen atom that is a coordinating atom. Further, R1 and R2 each represent an alkyl group having 1 to 6 carbon atoms.

Abstract: To provide a novel compound which can be used as a host material in which a light-emitting substance is dispersed. To provide a light-emitting element having a long lifetime. A compound represented by General Formula (G0). In the formula, A1 represents a dibenzo[f,h]quinoxalinyl group, A2 represents a benzo[b]naphtho[2,3-d]furanyl group, and Ar represents an arylene group having 6 to 25 carbon atoms. The dibenzo[f,h]quinoxalinyl group, the benzo[b]naphtho[2,3-d]furanyl group, and the arylene group are separately unsubstituted or substituted by any one of an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, and an aryl group having 6 to 13 carbon atoms.

Abstract: A light-emitting element that includes a fluorescent material and has a high emission efficiency is provided. A light-emitting element in which a delayed fluorescence component due to TTA accounts for a high proportion of emissive components is provided. A novel light-emitting device with a high emission efficiency and a low power consumption is provided. A light-emitting element includes an anode, a cathode, and an EL layer. The EL layer includes a light-emitting layer including a host material and an electron-transport layer including a first material in contact with the light-emitting layer. The LUMO level of the first material is lower than that of the host material. The proportion of a delayed fluorescence component due to TTA is greater than or equal to 10 percent of the light emission from the EL layer. The proportion of the delayed fluorescence component due to TTA may be greater than or equal to 15 percent of the light emission.

Abstract: A novel heterocyclic compound that can be used as a host material in which a light-emitting substance is dispersed. A light-emitting element having a long lifetime. A heterocyclic compound in which a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group is bonded to a substituted or unsubstituted arylene group having 6 to 25 carbon atoms which is bonded to any one of the 8-11 positions of a substituted or unsubstituted benzo[b]naphtho[1,2-d]furan skeleton.

Abstract: To provide a light-emitting element which uses a fluorescent material as a light-emitting substance and has higher luminous efficiency. To provide a light-emitting element which includes a mixture of a thermally activated delayed fluorescent substance and a fluorescent material. By making the emission spectrum of the thermally activated delayed fluorescent substance overlap with an absorption band on the longest wavelength side in absorption by the fluorescent material in an S1 level of the fluorescent material, energy at an S1 level of the thermally activated delayed fluorescent substance can be transferred to the S1 of the fluorescent material. Alternatively, it is also possible that the S1 of the thermally activated delayed fluorescent substance is generated from part of the energy of a T1 level of the thermally activated delayed fluorescent substance, and is transferred to the S1 of the fluorescent material.

Abstract: A novel organic compound that forms an exciplex emitting light with high efficiency is provided. An organic compound with a triarylamine skeleton in which the three aryl groups of the triarylamine skeleton are a p-biphenyl group, a fluoren-2-yl group, and a phenyl group to which a dibenzofuranyl group or a dibenzothiophenyl group is bonded. By the use of the organic compound and an organic compound with an electron-transport property, an exciplex that emits light with extremely high efficiency can be formed.

Abstract: A method for manufacturing a light-emitting element, in particular, a method for manufacturing a light-emitting element with high emission efficiency is provided. In the method for manufacturing a light-emitting element that includes a light-emitting layer containing a host material and a light-emitting material that is an organic compound or an organic metal complex, the light-emitting layer is formed by co-evaporation of the light-emitting material and the host material, and the light-emitting layer is deposited by co-evaporation while the percentage of the partial pressure of carbon dioxide with respect to the total pressure in an evaporation chamber for the co-evaporation is kept higher than that in the air.

Abstract: A light-emitting element which has low driving voltage and high emission efficiency, is provided. The light-emitting element includes, between a pair of electrodes, a hole-transport layer and a light-emitting layer over the hole-transport layer. The light-emitting layer contains a first organic compound having an electron-transport property, a second organic compound having a hole-transport property, and a light-emitting third organic compound converting triplet excitation energy into light emission. A combination of the first organic compound and the second organic compound forms an exciplex. The hole-transport layer contains at least a fourth organic compound whose HOMO level is lower than or equal to that of the second organic compound and a fifth organic compound whose HOMO level is higher than that of the second organic compound.