A fused polycyclic heteroaromatic compound represented by Chemical Formula 1, and an organic thin film, an organic thin film transistor, and an electronic device including the fused polycyclic heteroaromatic compound are provided. The fused polycyclic heteroaromatic compound may have a conjugation structure but reinforce planarity among adjacent rings and have further dense packing and thus much increase charge mobility.

An organic electroluminescence device having a layer of an organic light emitting medium which comprises (A) a specific arylamine compound and (B) at least one compound selected from specific anthracene derivatives, spirofluorene derivatives, compounds having condensed rings and metal complex compounds and is disposed between a pair of electrodes and an organic light emitting medium comprising the above components (A) and (B) are provided. The organic electroluminescence device exhibits a high purity of color, has excellent heat resistance and a long life and efficiently emits bluish to yellowish light. The organic light emitting medium can be advantageously used for the organic electroluminescence device.

The present disclosure provides an organic compound that has a mother skeleton with a fused-ring structure, an electron-withdrawing group bonded to the mother skeleton, and an electron-donating group bonded to the mother skeleton, wherein the electron-withdrawing group is bonded at a position satisfying the following relationship in the mother skeleton.

Σ|C.sub.H|>Σ|C.sub.L|  (1)

(C.sub.H: 2PZ atomic orbital coefficient of a carbon at a substitution site in the HOMO of the mother skeleton)

(C.sub.L: 2PZ atomic orbital coefficient of the carbon at the substitution site in the LUMO of the mother skeleton)

The present invention relates to the use of a square planar transition metal complex as dopant, charge injection layer, electrode material or storage material.

A light emitting device includes 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 includes a metal-assisted delayed fluorescent (MADF) emitter, a fluorescent emitter, and a host, and the MADF emitter harvests electrogenerated excitons and transfers energy to the fluorescent emitter.

The present invention relates to compounds of the formula (1), to the use thereof in electroluminescent devices, and particularly organic electroluminescence devices, comprising said compounds according to the invention.

##STR00001##

The present invention relates to organic light emitting elements, comprising thermally activated delayed fluorescence (TADF) emitters and/or hosts on basis of phthalimide and naphthalimide materials, which have a sufficiently small energy gap between S.sub.1 and T.sub.1 (ΔE.sub.ST) to enable up-conversion of the triplet exciton from T.sub.1 to S.sub.1. The organic light emitting elements show high electroluminescent efficiency.

A composition which is useful for producing a light emitting device having excellent external quantum efficiency and a light emitting device containing the composition are described. The light emitting device contains an anode, a cathode, and an organic layer disposed between the anode and the cathode and contains a composition containing at least two compounds (A) selected from the group consisting of a compound represented by the formula (FH) and a polymer compound containing a constitutional unit having a group obtained by removing from a compound represented by the formula (FH) one or more hydrogen atoms, and a compound (B) having a condensed hetero ring skeleton (b) containing a boron atom and a nitrogen atom in the ring.

##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.

The present disclosure relates to a plurality of host materials and an organic electroluminescent device comprising the same. The organic electroluminescent device of the present disclosure can exhibit excellent lifespan characteristics while maintaining high luminous efficiency by including a specific combination of a plurality of host compounds.