Patent ID: 7175922

Claim:
An organic light emitting device, comprising: a) a substrate; b) an anode and a cathode disposed over the substrate; c) a luminescent layer disposed between the anode and the cathode wherein the luminescent layer includes a host and at least one dopant; wherein the host of the luminescent layer includes a solid organic material comprising a mixture of at least two components wherein: i) the first component of the mixture is an organic compound containing at least one perylene carbocyclic ring structure or at least one mono-aza-perylene or poly-aza-perylene ring structure that transports either electrons or holes or both and forms both a monomer state and an aggregate state in said device, the aggregate state being either in a ground electronic state or in an excited electronic state, the ground electronic state and the excited electronic state having a different absorption or emission spectrum or both relative to the absorption or emission spectrum or both of the monomer state, respectively, or the first component of the mixture is an organic compound containing at least one perylene carbocyclic ring structure or at least one mono-aza-perylene or poly-aza-perylene ring structure that forms an aggregate state in said device the presence of which results in a quantum yield of luminescence of the monomer state that differs from the quantum yield of luminescence of the monomer state in the absence of the aggregate state, and wherein the first component is not a diarylamino-, arylalkylamino-, or dialkylamino-substituted perylene; and ii) the second component of the mixture is an organic compound that mixes with the first host component to form a continuous and substantially pin-hole-free layer; and wherein the host transfers electronic excitation energy to the dopant and the dopant emits light.