11.2: Novel Fluorene‐Based Blue Emitters for High Performance OLEDs

Abstract

High performance new blue‐emitting host‐dopant systems, which consist of pyrene‐substituted fluorene hosts such as DPYFL01 and diarylamino‐substituted origo(fluorenylene)s represented by BDT3FL as dopants, have been developed. The new host material,DPYFL01 showed high electron‐mobility with 1×10−3 cm2/Vs. A device using DPYFL01 demonstrated blue emission (CIE: x, y = 0.15–0.16, 0.20–0.21) with high power efficiency of 4.5 lm/W at 200 cd/m2. The use of 20%BDT3FL inDPYFL01 resulted in deep‐blue emission (CIE: 0.15, 0.15) while keeping high power efficiency of 4.6 lm/W at 3.1 V. The device‐structure optimization together with the use of an additional host,C‐H01 afforded deep‐blue emission (CIE: 0.15, 0.14) and higher power efficiency of 4.9 lm/W and external quantum efficiency of 3.9 % at 4.3 mA/cm2 with 200 cd/m2. Lifetime of the optimized device using 10 %BDT3FL was estimated to be over 10,000 hour at an initial luminance of 200 cd/m2.

Recent Development of Blue Fluorescent OLED Materials and Devices

“…There are a number of stable blue host materials that have been disclosed in the literature which can be roughly categorized into several major classes of compounds, namely, diarylanthracene [10], di(styryl)arylene (DSA) [11], fluorene [12], and pyrene [13] whose representative structures and corresponding acronyms are shown in Fig. 1.…”

Synthesis, electroluminescence, and photovoltaic cells of new vinylene‐copolymers with 4‐(anthracene‐10‐yl)‐2,6‐diphenylpyridine segments

“…6 Fluorene and/or anthracene-based compounds, in particular, are often used as emitting materials in electroluminescent (EL) devices. [7][8][9][10][11][12][13][14][15][16] On the basis of the previous reports, promising low molecular weight emitter for use in LEDs should have an appropriate HOMO/ LUMO band gap as compared with those of the electron-and hole-transporting materials, high PL quantum yield (U f ), good film-forming properties, and durability to heat during the vacuum deposition. [17][18][19] The U f is a major interest associated with the improvement of EL device efficiency, since the two properties are generally related.…”

Synthesis and Luminescence Property of 4,4′‐Bis(2,2‐di(4‐fluorophenyl)vinyl)biphenyl for Organic Blue‐Light‐Emitting Diodes

“…5,6 Blue fluorescent materials have been widely studied for a long time. There are a number of stable blue-lightemitting materials, which can be roughly categorized into several major classes of compounds, namely, metal complexes, 7,8 diarylanthracene, [9][10][11] distyrylarylene (DSA), [12][13][14] fluorene, [15][16][17] and pyrene. 18,19 One of the blue light emitter DPVBi (4,4'-bis(2,2-diphenylvinyl)-biphenyl) has received much attention since disclosed by Idemitsu in 1995.…”