Patent ID: 9698365
Date: 2017-07-04
CPC Classifications: C07F,C09K,H01L

Claim:
1. A light-emitting device comprising: a first light-emitting layer over an anode, the first light-emitting layer comprising a first phosphorescent compound, a first organic compound having an electron transport property, and a second organic compound having a hole-transport property; a second light-emitting layer over the first light-emitting layer, the second light-emitting layer comprising a second phosphorescent compound and the first organic compound; and a cathode over the second light-emitting layer, wherein the first phosphorescent compound is not the same compound as the second phosphorescent compound, and wherein an emission spectrum of an exciplex of the first organic compound and the second organic compound overlaps with an absorption spectrum of the first phosphorescent compound.