ELECTROLUMINESCENT ELEMENT AND LIGHT-EMITTING DEVICE

摘要

An electroluminescent element which can easily control the balance of color in white emission (white balance) is provided according to the present invention. The electroluminescent element comprises a first light-emitting layer containing one kind or two or more kinds of light-emitting materials, and a second light-emitting layer containing two kinds of light-emitting materials (a host material and a phosphorescent material) in which the phosphorescent material is doped at a concentration of from 10 to 40 wt %, preferably, from 12.5 to 20 wt %. Consequently, blue emission can be obtained from the first light-emitting layer and green and red (or orange) emission can be obtained from the second light-emitting layer. An electroluminescent element having such device configuration can easily control white balance since emission peak intensity changes at the same rate in case of increasing a current density.

主权项

1. An electroluminescent element comprising:
an electroluminescent layer formed between a pair of electrodes, wherein the electroluminescent layer comprises at least a first light-emitting layer and a second light-emitting layer, each of which has an emission peak in a wavelength region of 500 to 700 nm, and wherein the second light-emitting layer contains a phosphorescent material which forms excimer at a concentration of 10 to 40 wt %.