Novel phosphorescent tetradentate platinum (II) compounds comprising a twisted aryl group are provided. Also provided are novel phosphorescent tetradentate platinum (II) compounds comprising an imidazo[1,2-f]phenanthridine moiety. The compounds may be used in organic light emitting devices to provide improved device efficiency, line shape and lifetime.

A monoamine compound characterized by being represented by the following general formula (1). ##STR00001##
[In general formula (1), R.sup.1 to R.sup.3 each independently represent a phenyl group which may have a substituent in at least one of o- and m-positions, in which the substituent may be bonded to each other to form a cyclic structure. R.sup.1 to R.sup.3 are a group different from each other.]

Organometallic compounds comprising an imidazole carbene ligand having a N-containing ring fused to the imidazole ring are provided. In particular, the N-containing ring fused to the imidazole ring may contain one nitrogen atom or more than one nitrogen atom. These compounds may demonstrate high photoluminescent (PL) efficiency, Gaussian emission spectra, and/or short excited state lifetimes. These materials may be especially useful as blue phosphorescent emitters.

The present invention provides a new compound and an organic electronic diode using the same. The compound according to the present invention may be used as hole injection, hole transport, electron injection and transport, and light emitting materials in an organic light emitting diode and an organic electronic diode, and the organic electronic diode according to the present invention exhibits excellent efficiency, driving voltage, and life-span properties.

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.

An electroluminescent element which can easily control the balance of color in white emission (white balance) is provided according to the present invention. The electroluminescent element comprises a first light-emitting layer containing one kind or two or more kinds of light-emitting materials, and a second light-emitting layer containing two kinds of light-emitting materials (a host material and a phosphorescent material) in which the phosphorescent material is doped at a concentration of from 10 to 40 wt %, preferably, from 12.5 to 20 wt %. Consequently, blue emission can be obtained from the first light-emitting layer and green and red (or orange) emission can be obtained from the second light-emitting layer. An electroluminescent element having such device configuration can easily control white balance since emission peak intensity changes at the same rate in case of increasing a current density.

Novel phosphorescent tetradentate platinum (II) compounds comprising a twisted aryl group are provided. Also provided are novel phosphorescent tetradentate platinum (II) compounds comprising an imidazo[1,2-f]phenanthridine moiety. The compounds may be used in organic light emitting devices to provide improved device efficiency, line shape and lifetime.

A triarylamine derivative represented by a general formula (G1) given below is provided. Note that in the formula, Ar represents either a substituted or unsubstituted phenyl group or a substituted or unsubstituted biphenyl group; represents a substituted or unsubstituted naphthyl group; represents either hydrogen or a substituted or unsubstituted naphthyl group; n and m each independently represent 1 or 2; and R.sup.1 to R.sup.8 each independently represent any of hydrogen, an alkyl group having 1 to 6 carbon atoms, or a phenyl group.

##STR00001##

An anthracene derivative represented by a general formula (1) and an organic compound represented by a general formula (8) are provided. Further, by use of the anthracene derivative represented by the general formula (1), a light-emitting element with high emission efficiency can be obtained. Furthermore, by use of the anthracene derivative represented by the general formula (1), a light-emitting element that emits blue light with high color purity can be obtained.

##STR00001##

An organic electroluminescent device, which has a pair of electrodes and at least one organic layer including a luminescent layer between the pair of electrodes, wherein at least one layer between the pair of electrodes comprises at least one metal complex having a tridentate- or higher polydentate-chain structure ligand.