Light-emitting element and novel iridium complexes

Abstract

A light-emitting element comprising: a pair of electrodes; and at least one organic compound layer comprising a light-emitting layer provided between the electrodes, the light-emitting layer comprising at least one compound represented by the formula (1): 1 wherein R11 represents a substituent, R12 represents a hydrogen atom or a substituent, Y11 represents a substituted or unsubstituted nitrogen atom or a substituted or unsubstituted carbon atom, Z11 l represents a linking group, M11 represents a transition metal ion, L11 represents a ligand, X11 represents a counter ion, a bond between Y1 and a nitrogen atom is a single bond or a double bond, a bond between R11 and the nitrogen atom is a single bond or a double bond, n11 represents 0 or 1, n12 represents 0 or 1, providing that n12 is 0, Y11 and R11 may be linked together to form a nitrogen-containing hetero ring, m11 represents an integer of 1 to 3, m12 represents an integer of 0 to 8, and m13 represents an integer of 0 to 3, with at least one electron-withdrawing group being contained in the compound represented by the formula (1), wherein the light-emitting layer comprises a host compound and the compound represented by the formula (1), and the host compound has an energy level of a lowest triplet excited state (T1 level) of 62 kcal/mol (259 kJ/mol) to 85 kcal/mol (355 kJ/mol).

Dependencies are inferred from the claim text.