A near-infrared organic light emitting device comprises a first electrode; a hole transporting layer in contact with the first electrode; a second electrode; an electron transporting layer in contact with the second electrode; and an emissive layer between the hole transporting layer and the electron transporting layer, the emissive layer comprising a near-infrared emitter and an emissive host. The emissive host transfers energy to the near-infrared emitter.

A novel light-emitting device is provided. A light-emitting device with high emission efficiency is provided. A light-emitting device with a favorable lifetime is provided. A light-emitting device with low driving voltage is provided. A light-emitting device with favorable display quality is provided. A light-emitting device that includes an anode, a cathode, and an EL layer positioned between the anode and the cathode, in which the EL layer includes a hole-injection layer, a light-emitting layer, and an electron-transport layer; in which the electron-transport layer contains an electron-transport material and an alkali metal, an alkaline earth metal, a compound of an alkali metal or an alkaline earth metal, or a complex thereof; and in which the resistivity of the hole-injection layer is within a certain range, is provided.

An electrochromic compound having a structure represented by the following general formula (1): where each of X.sub.1 to X.sub.3 independently represents a carbon atom or a silicon atom, and each of R.sub.1 to R.sub.15 independently represents a member selected from the group consisting of a hydrogen atom, a halogen atom, a monovalent organic group, and a polymerizable functional group. ##STR00001##

Provided is a blue light-emitting material for organic light-emitting diode (OLED) comprising a phosphinine derivative and the OLED including the same. The light-emitting material for OLED of the present invention comprises the phosphinine derivative having an electron-withdrawing substituent at its C4 position of a phosphorus-containing six-membered ring. The OLED of the present invention has a pair of electrodes and organic layers including light-emitting layers between the pair of the electrodes, wherein the at least one light-emitting layer comprises an anthracene compound and the phosphinine derivative.

High performance OLED that includes deuterated compounds in the emissive layer are disclosed. The OLED includes an anode; a cathode; and an emissive layer, disposed between the anode and the cathode. In the OLED, the emissive layer includes a first phosphorescent emitter and a first host; the first phosphorescent emitter is a metal complex; the first host is partially or fully deuterated; and at least one additional condition is true.

[Problems] Provided are a highly marketable reversibly thermochromic composition that provides a black color during color development by using a fluoran derivative having a specific structure as an electron-donating color-developing organic compound, turns colorless during decoloration, and is excellent in contrast between a colored state and a decolored state and a microcapsule pigment encapsulating the same.

[Solution] Disclosed are a reversibly thermochromic composition including: (a) a fluoran derivative having a specific structure as an electron-donating color-developing organic compound; (b) an electron-accepting compound; and (c) a reaction medium which reversibly induces an electron transfer reaction between the component (a) and the component (b) in a specific temperature range, and a reversibly thermochromic microcapsule pigment encapsulating the same.

The present application belongs to the technical field of organic materials and provides a nitrogen-containing compound, an electronic component, and an electronic device. The nitrogen-containing compound has a structure shown in Chemical formula 1:

##STR00001##

Provided are an organic EL device material capable of reducing the driving voltage of an organic EL device and increasing the lifetime of the device as compared with a conventional organic EL device material, specifically an aromatic amine derivative represented by N(Ar.sup.a) (Ar.sup.b) (Ar.sup.c), and an organic EL device using the material. [Ar.sup.a is represented by the formula (II). (In the formula (II): L.sup.a represents a single bond or an arylene group; R.sup.1 to R.sup.4 each represent an alkyl group, an aryl group, or the like, and R.sup.3's or R.sup.4's, or R.sup.3 and R.sup.4 may be bonded to each other to form a ring; and o represents 0 to 3 and p represents 0 to 4.) Ar.sup.b is represented by the formula (III). (in the formula (III), X represents NR.sup.a, O, or S, and R.sup.a and R.sup.5 to R.sup.7 each represent an alkyl group, an aryl group, or the like, and R.sup.5's, R.sup.6's, or R.sup.7's adjacent to each other, or R.sup.5 and R.sup.6 may be bonded to each other to form a ring; n represents 2 to 4 when X represents NR.sup.a, and represents 0 to 4 when X represents O or S; and q represents 0 to 3, r and s each independently represent 0 to 4.) Ar.sup.c represents an aryl group, or is represented by the formula (III).] ##STR00001##

An organic electroluminescence device according to 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, in which the emission layer includes a polycyclic compound represented by Formula 1, thereby achieving improved emission efficiency: ##STR00001##

The present invention relates to organic light-emitting devices comprising (a) an anode, (i) a cathode, and (e) an emitting layer between the anode and cathode, comprising 2 to 40% by weight of a triplet emitter X having a difference of the singlet energy (E.sub.S1(X)) and the triplet energy (E.sub.T1(X)) of less than or equal to 0.4 eV [Δ(E.sub.S1(X))−(E.sub.T1(X))≤0.4 eV], 0.05 to 5.0% by weight of a fluorescent emitter Y and 55 to 97.95% by weight of a host compound(s), wherein the amount of the triplet emitter X, the fluorescent emitter Y and the host compound(s) adds up to a total of 100% by weight and the singlet energy of the triplet emitter X (E.sub.S1(X)) is greater than the singlet energy of the fluorescent emitter Y (E.sub.S1(Y)) [(E.sub.S1(X))>E.sub.S1(Y)]. By doping, for example, an emitting layer containing a luminescent organometallic complex having a small S.sub.1-T.sub.1 splitting, with a fluorescent emitter the emission decay time can significantly be shortened without sacrificing external quantum efficiency (EQE) because of very efficient energy transfer.