12‐1: Invited Paper: Recent Advances in Blue OLED Materials toward High Efficiency and Long Lifetime Devices

Since 1985, Idemitsu Kosan Co., Ltd. (Idemitsu) has continuously developed OLED materials with a primary focus on fluorescent blue emitters. Along with material development, performance enhancement through device structure optimization has also been actively explored. This paper reviews our progress in fluorescent blue technology and introduces recent advancements, including the Dual EML (a stacked emitting layer consisting of high‐T₁ and low T₁ blue hosts), the Dual HTL (a stacked hole transport layer combining high n and low n HTLs).