Blue Emitting Materials Based on Naphthylanthracene Derivatives Containing Electron-Withdrawing Fluorobenzenes.

We have designed and synthesized three blue emitters based on 9-naphthylanthracene derivatives connected with various electron-withdrawing group such as 4-fluorobenzene, 2,4-difluorobenzene and 2,3,4,5,6-pentafluorobenzene (1-3). Multilayered OLEDs with the structure of ITO (180 nm)/NPB (50 nm)/Blue materials 1-3 (30 nm)/TPBi (15 nm)/Liq (2 nm)/AI (100 nm) have been fabricated to investigate their electroluminescent properties. In particular, the device using 3 showed efficient blue electroluminescent properties with a luminous, power, external quantum efficiency and CIE coordinates of 0.71 cd/A, 1.98 Im/W, 1.34% at 20 mA/cm2 and (x = 0.16, y = 0.20) at 10.0 V, respectively. In addition, a deep blue OLED using 1 with CIE coordinates (x = 0.15, y = 0.11) at 10.0 V exhibited a luminous, power, external quantum efficiency of 2.12 cd/A, 3.04 Im/W and 1.17% at 20 mA/cm2, respectively.