Disclosed is a light emitting device that is capable of reducing lateral leakage current and a driving voltage by improving a structure for connecting a plurality of stacks to one another in a structure using the plurality of stacks, and a light emitting display device including the same. The light emitting device includes a first electrode and a second electrode facing each other, a plurality of stacks provided between the first electrode and the second electrode, and a charge generation layer including an electron generation layer and a hole generation layer stacked between the stacks, wherein the electron generation layer contains a first host of Formula 1 and a metal dopant, and the hole generation layer contains a second host and an organic dopant.

A light emitting element includes a first electrode, a second electrode, and an emission layer between the first electrode and the second electrode and includes a compound represented by Formula 1 below, thereby exhibiting a long service life characteristic.

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A polyimide luminescent material, a preparation method, and a used thereof are disclosed; the polyimide luminescent material includes a polyimide resin and a rare earth complex distributed in the polyimide resin, wherein the polyimide resin is a condensation polymer of an aromatic diamine containing a bidentate chelate ligand and an aromatic dianhydride, and the rare earth complex and the bidentate chelate ligand are connected by a chemical bond. The luminescent material has enhanced fluorescence intensity, thermal stability, and mechanical properties. The preparation method is simple and easy, and is suitable for industrial production.

Embodiments provide an organometallic compound, a light-emitting device including the organometallic compound, and an electronic apparatus including the light-emitting device. The light-emitting device includes a first electrode, a second electrode facing the first electrode, an interlayer between the first electrode and the second electrode and including an emission layer, and the organometallic compound, which is represented by Formula 1.

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The description of Formula 1 is provided in the specification.

Provided are a heterocyclic compound represented by Formula 1, a light-emitting device including the heterocyclic compound, and an electronic apparatus including the light-emitting device:

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wherein the detailed description of Formula 1 is the same as described in the specification.

The present disclosure relates to a plurality of host materials comprising at least one first host compound represented by the following formula 1 and at least one second host compound represented by the following formula 2, and an organic electroluminescent device comprising the same. By comprising the specific combination of the compound according to the present disclosure as host materials, an organic electroluminescent device having high luminous efficiency and/or long lifespan characteristics can be provided.

Provided is an organic electroluminescent device. The organic electroluminescent device is a blue delayed fluorescent device including an anode, a cathode, an emissive layer disposed between the anode and the cathode and a hole blocking layer disposed between the emissive layer and the cathode, where the hole blocking layer comprises a hole blocking material having a structure of Formula 1, and the emissive layer comprises a first host material, a second host material and a blue delayed fluorescent material having a structure of Formula 3. The blue delayed fluorescent device exhibits excellent overall device performance, such as higher efficiency and longer lifetime. Further provided are a light-emitting device comprising a blue delayed fluorescent unit, a green phosphorescent unit and a red phosphorescent unit and a display assembly comprising the blue delayed fluorescent device and the light-emitting device.

The present disclosure relates to a plurality of host materials comprising a first host material having a compound represented by formula 1, and a second host material having a compound represented by formula 2, and an organic electroluminescent device comprising the same. By comprising a specific combination of compounds of the present disclosure as host materials, it is possible to provide an organic electroluminescent device having long lifetime properties while having an equivalent or improved level of power efficiency compared to conventional organic electroluminescent devices.

Provided are organometallic compounds having a structure of

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

The present invention relates to heteroleptic carbene complexes comprising at least two different carbene ligands, to a process for preparing the heteroleptic carbene complexes, to the use of the heteroleptic carbene complexes in organic light-emitting diodes, to organic light-emitting diodes comprising at least one inventive heteroleptic carbene complex, to a light-emitting layer comprising at least one inventive heteroleptic carbene complex, to organic light-emitting diodes comprising at least one inventive light-emitting layer, and to devices which comprise at least one inventive organic light-emitting diode.