An organic light emitting device having an anode, a cathode and an organic layer disposed between the anode and the cathode is provided. In one aspect, the organic layer comprises a carbene compound ##STR00001##

The present Invention relates to an organic light emitting device comprising: (i) an anode; (ii) a cathode; (iii) at least one light emitting layer arranged between the anode and the cathode; (iv) optionally a first hole injection layer comprising a first hole injection compound, the first hole injection layer being arranged between the anode and the light emitting layer and the hole injection layer being adjacent to the anode; (v) a first hole transport layer comprising a first hole transport matrix compound wherein the first hole transport layer is arranged a) between the first hole injection layer and the light emitting layer and adjacent to the first hole injection layer; or b) between the anode and the light emitting layer and adjacent to the anode; (vi) a second hole injection layer arranged between the first hole transport layer and the light emitting layer, wherein the second hole injection layer is adjacent to the first hole transport layer and wherein the second hole injection layer comprises a second hole injection compound; wherein the second hole injection compound is a halo-genated fullerene, a partially or fully halogenated metal complex or a mixture thereof.

Light emitting nanoparticles have improved photostability, thermal stability and emission properties, and a process of preparing the nanoparticles.

The present invention relates to formulations which comprise at least one organic semiconductor, at least one metal complex and at least one solvent and the use of these formulations in electronic devices, in particular organic electroluminescent devices.

A crosslinkable quantum dot (QD) and a preparing method thereof, an array substrate made by using the crosslinkable quantum dot (QD) and a preparing method thereof are provided. The surface of the crosslinkable quantum dot has a pair of groups R1 and R2 capable of reacting to form a cross-linked network, or a group R3 capable of being cross-linked by a crosslinking agent to form a cross-linked network.

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 S.sub.1 level of the fluorescent material, energy at an S.sub.1 level of the thermally activated delayed fluorescent substance can be transferred to the S.sub.1 of the fluorescent material. Alternatively, it is also possible that the S.sub.1 of the thermally activated delayed fluorescent substance is generated from part of the energy of a T.sub.1 level of the thermally activated delayed fluorescent substance, and is transferred to the S.sub.1 of the fluorescent material.

An organometallic compound represented by Formula 1, wherein the organometallic compound has a horizontal orientation ratio of a transition dipole moment in a range of about 85 percent to about 100 percent:

M(L.sub.1).sub.nFormula 1 wherein, in Formula 1, M is selected from a first-row transition metal of the Periodic Table of Elements, a second-row transition metal of the Periodic Table of Elements, and a third-row transition metal of the Periodic Table of Elements, n is 2 or 3, L.sub.1 is a bidentate organic ligand bound to M, wherein L.sub.1 does not comprise a fluoro group (F), and wherein L.sub.1 groups in the number of n are identical to each other.

An inorganic nanoparticles-based structure in accordance with the present disclosure includes inorganic nano-particles; and a novel ligand coordinated to a surface of each of the inorganic nano-particles, wherein the ligand has a urethane bond resulting from reaction with an isocyanate compound having a double bond, and, thus, has a double bond at terminals thereof. Further, the present disclosure provides an optical member, a light-emitting device, and a quantum dot display device including the inorganic nanoparticles-based structure.

A light-emitting structure in accordance with the present disclosure includes inorganic nano-particles; ligands coordinated to surfaces of the inorganic nano-particles, wherein each of the ligands contains an acrylic polymer. Further, the present disclosure provides an optical member, a light-emitting device, and a liquid crystal device including the light-emitting structure.

A novel light-emitting device is provided. A light-emitting device with high emission efficiency is provided. A light-emitting device with a long 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. The electron-transport layer contains a material whose resistance decreases with current flowing therethrough.