| abstract |
The present invention discloses a phenanthroline derivative is represented by the following formula(I), the organic EL device employing the phenanthroline derivative as hole blocking electron transport material, electron transport material can display good performance like as lower driving voltage and power consumption, increasing efficiency and half-life time. n n n n n n n n n n wherein Ar, m, n, p and R 1 to R 4 are the same definition as described in the present invention. |