HOLE TRANSPORT COMPOSITIONS AND RELATED DEVICES AND METHODS (II)
A composition comprising: at least one compound comprising a hole transporting core, wherein the core is covalently bonded to a first arylamine group and also covalently bonded to a second arylamine group different from the first, and wherein the compound is covalently bonded to at least one intractability group, wherein the intractability group is covalently bonded to the hole transporting core, the first arylamine group, the second arylamine group, or a combination thereof, and wherein the compound has a molecular weight of about 5,000 g/mole or less. Blended mixtures of arylamine compounds, including fluorene core compounds, can provide good film formation and stability when coated onto hole injection layers. Solution processing of OLEDs is a particularly important application.