White light emitting internal junction organic electroluminescent device

Abstract

An internal junction organic electroluminescent device comprises, in sequence, an anode, an organic electroluminescent medium, and a cathode, the organic electroluminescent medium further comprising a hole injecting and transporting zone contiguous with the anode and an electron injecting and transporting zone contiguous with the cathode, the electron injecting and transporting zone further comprising an electron injecting layer in contact with the cathode, characterized in that the portion of the organic electroluminescent medium that is interposed between the electron injecting layer and the hole injecting and transporting zone is capable of emitting white light in response to hole-electron recombination and comprises a fluorescent material and a mixed ligand aluminum chelate of the formula (R.sup.s --Q).sub.2 --Al--O--L where Q in each occurrence represents a substituted 8-quinolinolato ligand, R.sup.s represents an 8-quinolinolato ring substituent chosen to block sterically the attachment of more than two substituted 8-quinolinolato ligands to the aluminum atoms, O--L is a phenolato ligand, and L is a hydrocarbon group that includes a phenyl moiety.

Dependencies are inferred from the claim text.