The present disclosure relates to a plurality of host materials and an organic electroluminescent device comprising the same. By comprising the specific combination of compounds according to the present disclosure as a plurality of host materials according to the present disclosure, it is possible to provide an organic electroluminescent device having improved driving voltage, luminous efficiency, and/or lifetime property compared to the conventional organic electroluminescent devices.

A display apparatus according to an embodiment includes light-emitting devices and an encapsulation member, wherein the encapsulation member includes a light absorber including a hexagonal heterocycle containing two or more nitrogen atoms as ring-forming atoms, and first to third substituents substituted at the hexagonal heterocycle, the first to third substituents being different from one another, and thus can effectively block external light, thereby exhibiting improved reliability.

A compound having structures represented by the following formulas (1) or (2): wherein in the formulas (1) and (2), at least one of R.sub.1 to R.sub.8 is a deuterium atom.

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The present application provides a nitrogen-containing compounds represented by formula I-A, electronic elements and electronic devices. The application relates to the field of organic material. The nitrogen-containing compounds can improve the performance of electronic elements.

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An organic electroluminescence device includes an anode, a cathode, an emitting layer between the anode and the cathode, and a first hole transporting layer between the anode and the emitting layer, in which the first hole transporting layer is directly adjacent to the emitting layer, the first hole transporting layer contains a first compound represented by formula (1) below, and the first compound has at least one group represented by formula (11) below.

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The present disclosure provides a blue organic electroluminescence device, a display panel, and a display apparatus. A blue organic electroluminescence device includes a light-emitting layer having a matrix material and a blue fluorescent doping material doped in the matrix material, where dipole moments of the matrix material and the blue fluorescent doping material are both 0 to 1 D, which can ensure higher energy transfer efficiency and charge balance, ensure that an emission spectrum is a narrow spectrum, and thus have better color purity and higher external quantum Efficiency (EQE) to obtain the blue organic electroluminescence devices with high color purity and high luminous efficiency.

The present invention addresses the problem of providing: a luminescent thin film, a luminescent multilayered film, and an organic electroluminescent element that have luminescence properties with excellent storage stability in atmospheric air; and a production method therefor. This luminescent thin film contains a luminescent compound A, and is characterized by containing 0.0001 mass % or more of an oxide B of luminescent compound A in terms of the luminescent compound A.

Provided are an organic electroluminescence device, which shows high luminous efficiency, is free of any pixel defect, and has a long lifetime, and a material for an organic electroluminescence device for realizing the device. The material for an organic electroluminescence device is a compound having a π-conjugated heteroacene skeleton crosslinked with a carbon atom, nitrogen atom, oxygen atom, or sulfur atom. The organic electroluminescence device has one or more organic thin film layers including a light emitting layer between a cathode and an anode, and at least one layer of the organic thin film layers contains the material for an organic electroluminescence device.

Provided is a compound of Formula I

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in which at least one moiety A, moiety B, moiety C, or moiety D is a 6-membered carbocyclic or heterocyclic ring, and at least one R.sup.A, R.sup.B, R.sup.C, or R.sup.D includes a group having Formula II

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where R.sup.X can be silyl, germyl, boryl, nitrile, F, CF.sub.3, cycloalkyl, heterocycloalkyl, or monocyclic heteroaryl. The compounds are useful as emitters in OLEDs providing improved efficiency.

An organic electroluminescence device includes an emitting region provided between an anode and a cathode, in which the emitting region includes a first emitting layer and a second emitting layer, a ratio D.sub.EM1/D.sub.EM2 of a film thickness of the first emitting layer D.sub.EM1 to a film thickness of the second emitting layer D.sub.EM2 is in a range from 2/3 to 3/2, the first emitting layer contains a first host material and a first emitting compound, the second emitting layer contains a second host material and a second emitting compound, and the first host material has a group represented by a formula (10) below and is a compound represented by a formula (1) below. ##STR00001##