Disclosed is an organic electroluminescent device (organic EL device) which is improved in luminous efficiency, fully secured of high driving stability, and of a simple structure. The organic EL device is constituted of an anode, organic layers containing a phosphorescent light-emitting layer, and a cathode piled one upon another on a substrate and a phosphine oxide derivative represented by general formula (1) is contained in a phosphorescent light-emitting layer, an electron-transporting layer, a hole-blocking layer, or an exciton-blocking layer. In general formula (1), L1 is a direct bond or an aromatic group with a valence of 1-3 and Ar1 is an aromatic group. The two Ar1 groups linked to the same nitrogen atom may form a nitrogen heterocycle and may further form a fused ring together with the said nitrogen heterocycle.
本发明公开了一种有机电致发光器件(有机 EL 器件),它的发光效率更高,完全确保了高驱动稳定性,而且结构简单。该有机电致发光器件由堆叠在基板上的阳极、含有
磷光发光层的有机层和阴极构成,在
磷光发光层、电子传输层、空穴阻挡层或激子阻挡层中含有通式(1)表示的氧化膦衍
生物。在通式(1)中,L1 是直接键或价数为 1-3 的芳香基团,Ar1 是芳香基团。与同一氮原子相连的两个 Ar1 基团可形成一个氮杂环,并可进一步与所述氮杂环一起形成一个融合环。