Kyoto University and JNC Develop Next-Generation Deep Blue OLED via “Double Borylation” Technique

A joint research team led by Professor Takuji Hatakeyama from the Department of Chemistry at Kyoto University, in collaboration with JNC Co., Ltd., has developed a novel ‘Double Borylation’ synthetic strategy and successfully realized a world-leading pure Deep Blue OLED emitting material. This achievement was published in the international journal Nature Communications (October 2025, DOI: 10.1038/s41467-025-63908-y) and is anticipated to be a core technology for next-generation displays such as high-resolution micro-OLEDs.

Among the three primary colors (RGB) for OLEDs, the ‘Deep Blue’ region is known to be the most challenging to achieve. This is because producing a deeper blue color leads to increasingly unstable charge recombination, resulting in reduced efficiency and shortened lifetime. To address this issue, Professor Hatakeyama’s research team proposed a novel ‘Double Borylation’ strategy. This involves selectively introducing two boron atoms into the multi-resonance (MR)-TADF luminescent skeleton, which is composed of boron (B) and nitrogen (N).

Schematic illustration of the double borylation reaction introducing two boron atoms into the ν-DABNA structure for OLED emitter design (Source: Nature Communications, 2025)

Double Borylation Reaction of ν-DABNA for OLED Emitters (Source: Nature Communications, 2025)

This process expands the molecule’s π (pi) resonance structure, increasing the electronic transition energy, strengthening the transition dipole moment, and reducing the singlet-triplet energy gap (ΔE_ST). As a result, it improved efficiency, color purity, and stability. The newly synthesized material ‘ν-DABNA-M-B-Mes’ exhibits a deep blue wavelength of 463 nm, surpassing the previously reported deep blue material ν-DABNA, and achieved the following performance:

Photoluminescence Quantum Efficiency (PLQY): 93%.
Emission half-width at half-maximum (FWHM): 16 nm (world’s smallest)
External Quantum Efficiency (EQE): 32% or better
Color coordinates (CIE y): 0.09 – close to NTSC standard blue (0.08)
Lifetime (based on LT80, 100 cd/m²): More than 1,000 hours

In addition, the Phosphor-Sensitized Fluorescence (PSF) structure, which is attracting attention as a fourth-generation hyperfluorescent material, achieved a low drive voltage (2.5 V), maintained efficiency (minimized roll-off), and a lifetime of LT₈₀ > 1,000 hours at a luminance of 100 cd/m².

Prof. Hatakeyama said that Double Borylation is not just a synthesis technique, but a strategic approach that changes the fundamental concept of OLED material design, and succeeds in improving color purity, efficiency, and lifetime, and is expected to be used in a variety of next-generation applications, including microOLEDs (OLEDoS) for AR-VR, ultra-high color purity smartphone and TV displays, automotive heads-up displays (HUDs), wearables, and transparent displays.