To provide a composition which is useful for production of a light emitting device excellent in external quantum efficiency.
A composition comprising two or more compounds represented by the formula (C-1) and a phosphorescent compound, wherein at least one of the above-described two or more compounds represented by the formula (C-1) is a compound represented by the formula (C-1) in which RC is a group represented by the formula (C'-1) :
[wherein,
Ring R1C and Ring R2C represent an aromatic hydrocarbon ring or an aromatic hetero ring.
RC represents an oxygen atom, a sulfur atom or a group represented by the formula (C'-1).]
[wherein,
Ring R3C and Ring R4C represent an aromatic hydrocarbon ring or an aromatic hetero ring.
RC' represents a carbon atom, a silicon atom, a germanium atom, a tin atom or a lead atom.].
提供一种可用于生产外部量子效率极佳的发光器件的组合物。
一种由两种或两种以上由式(C-1)表示的化合物和一种
磷光化合物组成的组合物,其中上述两种或两种以上由式(C-1)表示的化合物中至少有一种是由式(C-1)表示的化合物,其中 RC 是由式(C'-1)表示的基团:
其中
环 R1C 和环 R2C 代表
芳香烃环或芳香杂环。
RC 代表氧原子、
硫原子或由式(C'-1)代表的基团]。
其中
环 R3C 和环 R4C 代表
芳香烃环或芳香杂环。
RC'代表碳原子、
硅原子、
锗原子、
锡原子或
铅原子]。