A light emitting device includes a first electrode, a second electrode facing the first electrode, and organic layers disposed between the first electrode and the second electrode, wherein the organic layers include at least one organic layer that includes an amine compound represented by Formula 1. The light emitting device may exhibit improved luminous efficiency characteristics.

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A light-emitting device including a first electrode, a hole transport region disposed on the first electrode, a first light-emitting layer disposed on the hole transport region and emitting light of a first wavelength, a second light-emitting layer disposed on the hole transport region and emitting light of a second wavelength different from the first wavelength, an electron transport region disposed on the first light-emitting layer and the second light-emitting layer, and a second electrode disposed on the electron transport region, wherein the second light-emitting layer includes a first sub light-emitting layer including a first host and a first dopant and emitting the light of the second wavelength, and a second sub light-emitting layer including a second host different from the first host and a second dopant and emitting the light of the second wavelength. Accordingly, a luminous efficiency and device lifetime of the light-emitting device may be improved.

An organic electroluminescence device including a cathode, an anode, and an emitting layer disposed between the cathode and the anode, wherein the emitting layer includes a compound represented by the following formula (1) and one or more compounds selected from the group consisting of compounds represented by each of formulas (11), (21), (31), (41), (51), (61), (71) and (81). In the formula (1), at least one of R.sub.1 to R.sub.8 is a deuterium atom, and Ar.sub.2 is a monovalent group represented by following formula (2), (3) or (4).

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Provided is an organometallic compound including a first ligand L.sub.A selected from

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In ligand L.sub.A, each of Y.sup.1 to Y.sup.10 is carbon or nitrogen; moiety B is a monocyclic or polycyclic fused ring structure including 5-membered and/or 6-membered rings; any two R.sub.A and R.sub.B can be fused or joined to form a ring; X is selected from O, S, Se, or NR; each R.sub.A and R.sub.B is independently hydrogen or a substituent selected from the general substituent defined herein; at least one R, R.sub.A, or R.sub.B is deuterium or a linking group between L.sub.A and another ligand that includes a deuterium substituted aromatic ring; and L.sub.A is coordinated to a metal M, selected from Os, Pd, Pt, Ir, Cu, Ag, or Au; and the compound is capable of emitting light with a peak maximum wavelength (λ.sub.max)≥700 nm at room temperature.

A compound represented by the following formula (1) (In the formula (1), at least one of R.sub.1 to R.sub.8 is a deuterium atom; Ar.sub.2 is a monovalent group represented by the following formula (2), (3) or (4)).

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Provided are boron substituted organometallic compounds of Formula I:

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Also provided are formulations including these organometallic compounds. Further provided are OLEDs and related consumer products that utilize these organometallic compounds.

An organic light-emitting device having low-driving voltage, improved efficiency, and long lifespan includes: a first electrode; a second electrode facing the first electrode; a first layer between the first electrode and the second electrode, the first layer including a first compound; a second layer between the first layer and the second electrode, the second layer including a second compound; and a third layer between the second layer and the second electrode, the third layer including a third compound; wherein the first compound does not include a nitrogen-containing heterocyclic group comprising *═N—*′ as a ring forming moiety, and wherein the first compound, the second compound, and the third compound each independently include at least one group selected from groups represented by Formulae A to C:

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An organic light-emitting device including a first electrode, a second electrode facing the first electrode, and an organic layer disposed between the first electrode and the second electrode, wherein the organic layer includes an emission layer, wherein the emission layer includes an electron transport host, a hole transport host, and a dopant, wherein the dopant includes an organometallic compound, and wherein the organometallic compound does not comprise iridium, wherein the organic light-emitting device satisfies predetermined parameters described in the specification.

Provided is a light-emitting element including a fluorescence-emitting material with high emission efficiency. The light-emitting element includes a pair of electrodes and an EL layer between the pair of electrodes. The EL layer includes a first organic compound, a second organic compound, and a guest material. The first organic compound has a function of emitting a thermally activated delayed fluorescence at room temperature. The guest material has a function of emitting fluorescence. A HOMO level of the first organic compound higher than or equal to a HOMO level of the second organic compound. A LUMO level of the first organic compound is lower than or equal to a LUMO level of the second organic compound.

A printing formulation, an electronic device comprising a function layer prepared from the printing formulation and a preparation method for obtaining a functional material thin film by utilizing the printing formulation. The printing formulation comprises at least one functional material and at least one inorganic ester solvent, and the inorganic ester solvent can be selected from alkyl borate or alkyl phosphate.