Abstract: An OLED device comprises an anode and a cathode and having therebetween a light emitting layer containing an emissive material, wherein a layer between the anode and cathode contains a phosphineoxide compound bearing two or more tri(hetero)arylphosphineoxide groups, provided these groups are selected to give a compound with a Et?2.65 eV.

Abstract: Disclosed is an electroluminescent device comprising a light-emitting layer containing a light emitting phosphorescent material that contains an organometallic complex comprising a metal selected from the group consisting of Mo, W, Re, Ru, and Os that is coordinated to a neutral or negatively-charged ligand group through the ? electrons of the ligand with a hapticity greater than 2. The device provides useful light emissions.

Abstract: Disclosed is a useful electroluminescent device comprising a cathode, an anode, and therebetween a light emitting layer containing a host material and a phosphorescent light-emitting material wherein the host material is represented by formula (1): X?-A-X? ??(1) wherein: A is selected from the group consisting of an unsubstituted phenylene ring, a biphenylene group, a terphenylene group, a naphthylene group, and a fluorene group; and each of X? and X? is an independently selected aromatic group bearing an ortho aromatic substituent.

Abstract: Disclosed is an electroluminescent device comprising a light-emitting layer containing a light emitting phosphorescent material that contains an organometallic complex comprising a metal selected from the group consisting of Mo, W, Re, Ru, and Os that is coordinated to a neutral or negatively-charged ligand group through the ? electrons of the ligand with a hapticity greater than 2. The device provides useful light emissions.

Abstract: Disclosed is an electroluminescent device comprising a cathode, an anode, and located therebetween a light emitting layer (LEL) containing (1) a host material that comprises a N,N,N?,N?-tetra-aromatic benzidine group substituted in at least one position ortho to the biphenyl linkage between the phenyl groups of the benzidine nucleus and (2) a phosphorescent light emitting material, wherein the triplet state energy of the benzidine nucleus is higher than the triplet state energy of the phosphorescent emitting material.

Abstract: Disclosed is an electroluminescent device comprising a light-emitting layer containing a light emitting phosphorescent material that contains an organometallic complex comprising iridium and an indole compound with an unsubstituted phenyl ring or comprising Ir, Rh, Os, Ru, Pt, and Pd and an isoindole compound. The invention further comprises compositions of certain such complexes as well as a display or area lighting devices and a process for emitting light. The organometallic materials function as useful phosphorescent light emitting materials in electroluminescent devices.

Abstract: Disclosed is an electroluminescent device comprising a light-emitting layer including a light emitting material that contains an organometallic complex comprising (1) a metal selected from the group consisting of Ir, Rh, Os, Pt, and Pd and (2) a diazole group ligand wherein the ligand has a fused aromatic ring group including a nitrogen of the diazole as a bridgehead nitrogen. The device provides useful light emission.

Abstract: Disclosed is an electroluminescent device comprising a light-emitting layer containing a phosphorescent light emitting material that contains an organometallic complex comprising a metal selected from the group consisting of Ir, Rh, Os, Pt, and Pd and a pyrazole compound fused with at least one aromatic ring. The device provides useful light emissions.

Abstract: Disclosed is an OLED device comprising a light-emitting layer (LEL) containing a host and a dopant located between a cathode and an anode wherein the emitter is an orange-red light emitting rubrene derivative represented by formula (I): wherein: a) there are identical oxy, aza or thio groups at the 2- and 8-positions; b) the phenyl rings in the 5- and 11-positions contain only para-substituents identical to the oxy, aza or thio groups in paragraph a); c) the phenyl rings in the 6- and 12-positions are substituted; and provided that when a single substituent on both phenyl rings in paragraph c) are present, said substituent is not a methoxy group located at the para-position.

Abstract: Disclosed is an OLED device comprising a light-emitting layer (LEL) containing a host and a dopant located between a cathode and an anode wherein the emitter is an orange-red light emitting rubrene derivative represented by formula (I): wherein: a) there are identical aromatic groups at the 2- and 8-positions; b) the phenyl rings in the 5- and 11-positions contain only para-substituents identical to the aromatic groups in paragraph a); and c) the phenyl rings in the 6- and 12-positions are substituted or not.

Abstract: Disclosed is an OLED device comprising a light-emitting layer (LEL) containing a host and a dopant located between a cathode and an anode wherein the emitter is an orange-red light emitting rubrene derivative represented by formula (II): wherein: a) there are identical branched alkyl or non-aromatic carbocyclic groups at the 2- and 8-positions; b) the phenyl rings in the 5- and 11-positions contain only para-substituents identical to the branched alkyl or non-aromatic carbocyclic groups in paragraph a); and c) the phenyl rings in the 6- and 12-positions are substituted.