A light emitting device with excellent light emission efficiency is provided. The light emitting device has an anode, a cathode, a first layer disposed between the anode and the cathode, and a second layer disposed between the anode and the first layer. The second layer is a layer containing a crosslinked product of a compound having a crosslinkable group selected from Group A, and at least one of the first layer and the second layers contains a compound represented by the formula (T-1). The compound having a crosslinkable group is a polymer compound having a crosslinkable group selected from Group A:

##STR00001## ##STR00002##

A particle having an inorganic matrix material and a light-emitting polymer wherein the light-emitting polymer has a light-emitting group and a host repeat unit, wherein a bandgap of the host repeat unit is greater than that of the light-emitting group, wherein the light-emitting group makes up no more than 10 mol % of the groups of the light-emitting polymer and wherein the polymer has a solubility in water or a Ci-s alcohol at 20° C. of at least 0.1 mg/mL.

A perovskite light emitting diode having degradation of the characteristics of the light emitting device, caused by PEDOT:PSS can be improved by replacing PEDOT:PSS contained in a conventional hole transport layer with an anionic conjugated polymer having ammonium-based counter ions, and the light emission characteristics can be greatly improved by passivating defects of a perovskite light emitting layer with a hole transport layer containing a conjugated polymer and increasing crystal growth.

An electroluminescent device and including a first electrode and a second electrode facing each other; an emission layer disposed between the first electrode and the second electrode, wherein the emission layer includes a quantum dot and a first electron transporting material represented by Chemical Formula 1; a hole transport layer disposed between the emission layer and the first electrode; and an electron transport layer disposed between the emission layer and the second electrode: ##STR00001## wherein, the definitions of groups and variables in Chemical Formula 1 are the same as described in the specification.

The present disclosure provides a light emitting device having an anode and a cathode, and a first layer and a second layer disposed between the anode and the cathode.

It is an object of the present invention to provide a composition for light emitting diodes with which it is possible to obtain an organic EL element that includes an organic layer formed using a high molecular weight material and whose service life can be extended as compared with that of conventional organic EL elements. The present invention provides a composition for light emitting diodes containing a high molecular weight compound and a thermally crosslinkable low molecular weight compound, wherein the thermally crosslinkable low molecular weight compound includes a compound that has two or more thermally crosslinkable structures in a molecule. The thermally crosslinkable low molecular weight compound preferably includes a compound that contains two or more thermally crosslinkable structures selected from the group consisting of an acrylate structure, a methacrylate structure, and a maleimide structure in a molecule.

An organic light emitting device of an embodiment of the present disclosure includes a first electrode, a hole transport region, an emission layer, an electron transport region, and a second electrode, stacked one by one, wherein the hole transport region includes a hole transport material derived from a crosslinking agent compound represented by Formula 1. The organic light emitting device may be manufactured through a wet process, and the emission efficiency and driving voltage properties of the organic light emitting device may be improved. ##STR00001##

A quantum dot device includes: a first electrode and a second electrode facing each other; a quantum dot layer between the first electrode and the second electrode, and an electron auxiliary layer between the quantum dot layer and the second electrode, the electron auxiliary layer including a first nanoparticle and a second nanoparticle which is larger than the first nanoparticle, wherein a work function of the first electrode is greater than a work function of the second electrode, and wherein a difference between a lowest unoccupied molecular orbital energy level of the quantum dot layer and a lowest unoccupied molecular orbital energy level of the electron auxiliary layer is less than about 1.1 electronvolts.

The present invention is directed to an ink composition for forming an organic semiconductor layer, wherein the ink composition comprises: —at least one p-type dopant comprising electron withdrawing groups; —at least one first auxiliary compound, wherein the first auxiliary compound is an aromatic nitrile compound, wherein the aromatic nitrile compound has about ≥1 to about ≤3 nitrile groups and a melting point of about <100° C., wherein the first auxiliary compound is different from the p-type dopant; and wherein the electron withdrawing groups are fluorine, chlorine, bromine and/or nitrile.

The present disclosure discloses a quantum dot light emitting device, a preparation method therefor and a display apparatus. In the present disclosure, at least one of one or more layers of light emitting functional layers is disposed to include at least two sub-function layers, the sub-function layers comprise ligands, and surface energies of the ligands corresponding to sub-function layers change in gradient along a transmission direction of carriers in the sub-function layers, so that energy levels of the sub-function layers change in gradient. In this way, the energy levels of the sub-function layers can be matched with the energy levels of the adjacent light emitting function layers, so that carrier transmission and balance as well as device efficiency can be improved.