P-161: 89.3% Lifetime Elongation of Blue TTA-OLED with Assistant Host

Operation lifetime of a blue OLED exhibiting triplet-triplet annihilation increased by 89.3% with the incorporation of 10% assistant host in the emitting layer, which increased diffusion length of singlet exciton, reduced the quenching of triplet exciton, and blocked the triplet pair diffusion.