Provided is an organic light-emitting device including a first compound and a second compound that offers low driving voltage and high efficiency. The organic light-emitting device includes an emission layer between a first electrode and a second electrode, and an electron transport region between the second electrode and the emission layer. The electron transport region includes the first compound. A hole transport region between the first electrode and the emission layer includes the second compound.

The present invention includes novel compounds containing heterocycles or azaheterocycles and fused phenylene or aza and cyano substituted variants thereof. These compounds may be useful as host materials for phosphorescent electroluminescent devices. In some embodiments, the invention includes compounds of Formula I: ##STR00001##

Novel organic compounds comprising a bicarbazole core are provided. In particular, the compounds has a 3,3′-bicarbazole core substituted at the 9-position with a triazine or pyrimidine. The compounds may be used in organic light emitting devices to provide devices having improved efficiency and improved lifetime.

An organic light-emitting device and a flat panel display device, the organic-light emitting device including an anode; a cathode; and an organic layer therebetween including an emission layer, a hole transport region between the anode and the emission layer, the hole transport region including at least one of a hole injection layer, a hole transport layer, and an electron blocking layer, an electron transport region between the emission layer and the cathode, the electron transport region including at least one of a hole blocking layer, an electron transport layer, and an electron injection layer, and a buffer layer between the emission layer and the electron transport region, wherein the buffer layer includes a biscarbazole-based derivative and triphenylene-based derivative, and a triplet energy (E.sup.T1) of the biscarbazole-based derivative or the triphenylene-based derivative and a triplet energy (E.sup.T2) of a dopant of the emission layer satisfy the following relationship:
E.sup.T1>E.sup.T2.

Small organic molecule semi-conducting chromophores containing a halogen-substituted core structure are disclosed. Such compounds can be used in organic heterojunction devices, such as organic small molecule solar cells and transistors.

An organic EL device of the disclosure includes: a first electrode and a second electrode; and an organic layer provided between the first electrode and the second electrode. The organic layer includes a light-emitting layer. The organic layer includes, between the first electrode and the light-emitting layer, a first layer that contains a polycyclic aromatic hydrocarbon compound having orientation, and a second layer that contains a larger amount of nitrogen element than the first layer.

A compound having a formula M(L.sub.A)(L.sub.B)(L.sub.C) is described. In formula M(L.sub.A)(L.sub.B)(L.sub.C), ligands L.sub.A and L.sub.B are each a mono-anionic bidentate ligand coordinated to metal M forming a 5-member cyclometalated ring and ligands L.sub.A and L.sub.B are covalently linked by a linking group. There is at least one loop of M-L.sub.A-linking group-L.sub.B-M having only arylene or heteroarylene groups in the loop other than M. In the compound, each ring in the linking group is part of a backbone of the loop; and either (i) the loop comprises a specific DBX moiety and the linking group comprises two or more arylene or heteroarylene groups, or (ii) the linking group comprises three or more arylene or heteroarylene groups. Formulations, OLEDs, and consumer product containing the compound are also disclosed.

A compound having a formula M(L.sub.A)(L.sub.B)(L.sub.C) is disclosed. Each of ligands L.sub.A and L.sub.B are mono-anionic bidentate ligands coordinated to metal M forming a 5-member cyclometalated ring. Ligands L.sub.A and L.sub.B are covalently linked by a first linking group, where there is at least one loop of M-L.sub.A-first linking group-L.sub.B-M having only carbocyclic or heterocyclic groups in the loop other than M. Wherein the first linking group includes multiple aliphatic or aromatic rings that are separated by at least one single bond, where each ring in the first linking group is part of the backbone of the loop. Devices, such as organic light emitting diodes, including the compounds are also disclosed.

The present disclosure provides a packaging cover plate, a method for manufacturing the same and a light emitting diode display, the packaging cover plate includes a cover plate body and a groove structure disposed on a first surface of the cover plate body, wherein the cover plate body comprises a flexible ceramic material, and the groove structure is filled with an adhesive material and a thermally conductive material. The packaging cover plate provided by the present disclosure has a bending property while having a barrier to water and oxygen, and does not undergo a shape change due to thermal expansion and contraction under a change of the ambient temperature. In addition, the present disclosure can improve the adhesion between the package cover plate and the packaging adhesive and improve the heat dissipation effect.

The present disclosure provides an organic light emitting device having improved driving voltage, efficiency and life time.