A compound comprising a ligand L.sub.A coordinated to a metal M ##STR00001## wherein ring A, ring T, and ring W are independently selected from a 5-membered or 6-membered heterocyclic or carbocyclic ring, and the ring W is fused to the ring T. The metal compounds having a ligand L.sub.A can be found in an OLED that includes an organic layer positioned between an anode and a cathode where the organic layer comprises a metal compound above having a ligand L.sub.A disclosed herein. We also describe a consumer product comprising the OLED.

A red light thermally activated delayed fluorescence material, a method for preparing the same, and an organic light emitting diode (OLED) device are provided. The OLED device has a luminescent material layer containing the red light thermally activated delayed fluorescence material. The red light thermally activated delayed fluorescence material has a specific molecular structure. The OLED device has a maximum brightness ranging from 1300 to 1800 cd/m.sup.2 and a maximum current efficiency ranging from 25 to 35 cd/A.

The present invention relates to a polycyclic aromatic derivative compound that can be used in a variety of organic material layers in an organic light-emitting element, and an organic light-emitting element comprising the polycyclic aromatic derivative compound, the highly efficient and long-life organic light-emitting element having significantly improved light-emitting efficiency by employing the polycyclic aromatic compound as a dopant compound in a light-emitting layer, and an anthracene derivative having a particular structure as a host compound.

The present invention relates to metal complexes and to electronic devices, in particular organic electroluminescent devices, comprising these metal complexes.

Fluorene derivatives that are connected in one or more of the 1-, 1′-, 4-, or 4′-positions in any combination to a carbon atom of a diaryl substituted triazinyl or pyrimidinyl derivative. The fluorene derivatives are not spirobifluorene derivatives. The compounds are suitable for use in electronic devices, in particular organic electroluminescent devices, comprising these compounds. In some embodiments, the compounds are used as matrix materials for phosphorescent or fluorescent emitters as well as a hole-blocking or an electron-transport layer.

This invention relates to compounds containing heterocycles or azaheterocycles and phenylene or azaphenylene wherein at least one ring is a five-membered ring. These novel compounds are useful as host materials for phosphorescent electroluminescent devices.

A phosphorescent emitter or delayed fluorescent and phosphorescent emitters represented by Formula I or Formula II, where M is platinum or palladium.

##STR00001##

Compounds comprising phosphorescent metal complexes comprising cyclometallated ligands having a structure of ##STR00001##
In the vgs3, each of the E.sup.1 atoms is selected from C and N, except that E.sup.1g is selected from C, N, and S. The E.sup.1 atoms collectively comprise an 18 pi-electron system, provided that E.sup.1a and E.sup.1p are different. The R.sup.1 substituents are each, independently, H, hydrocarbyl, heteroatom substituted hydrocarbyl, cyano, fluoro, OR.sup.2a, SR.sup.2a, NR.sup.2aR.sup.2b, BR.sup.2aR.sup.2b, or SiR.sup.2aR.sup.2bR.sup.2c, where the R.sup.2 substituents are each, independently, hydrocarbyl or heteroatom substituted hydrocarbyl. Any of the R.sup.1 or R.sup.2 substituents can be linked to form a saturated or unsaturated, aromatic or non-aromatic ring, provided that the R.sup.1 substituents are not present when the corresponding one of E atoms is N or S. Organic light emitting diode devices comprising these compounds are also described.

An organometallic compound represented by Formula 1:

M(L.sub.1).sub.n1(L.sub.2).sub.n2   Formula 1 wherein, Formula 1, M is a transition metal, L.sub.1 is a ligand represented by Formula 2 as provided herein, L.sub.2 is a ligand represented by Formula 3 as provided herein, and n1 and n2 are each independently 1 or 2.

A phosphorescent emitter or delayed fluorescent and phosphorescent emitters represented by Formula I or Formula II, where M is platinum or palladium. ##STR00001##