title: Microfluidic White Organic Light-Emitting Diode Based on Integrated Patterns of Greenish-Blue and Yellow Solvent-Free Liquid Emitters.
abstract: We demonstrated a novel microfluidic white organic light-emitting diode (microfluidic WOLED) based on integrated sub-100-μm-wide microchannels. Single-μm-thick SU-8-based microchannels, which were sandwiched between indium tin oxide (ITO) anode and cathode pairs, were fabricated by photolithography and heterogeneous bonding technologies. 1-Pyrenebutyric acid 2-ethylhexyl ester (PLQ) was used as a solvent-free greenish-blue liquid emitter, while 2,8-di-tert-butyl-5,11-bis(4-tert-butylphenyl)-6,12-diphenyltetracene (TBRb)-doped PLQ was applied as a yellow liquid emitter. In order to form the liquid white light-emitting layer, the greenish-blue and yellow liquid emitters were alternately injected into the integrated microchannels. The fabricated electro-microfluidic device successfully exhibited white electroluminescence (EL) emission via simultaneous greenish-blue and yellow emissions under an applied voltage of 100 V. A white emission with Commission Internationale de l'Declairage (CIE) color coordinates of (0.40, 0.42) was also obtained; the emission corresponds to warm-white light. The proposed device has potential applications in subpixels of liquid-based microdisplays and for lighting.
authors.affiliation: Faculty of Science and Engineering, Waseda University 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan.
authors.forename: Naofumi
authors.initials: N
authors.lastname: Kobayashi
authors.affiliation: Faculty of Science and Engineering, Waseda University 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kasahara
authors.affiliation: Development Department, Shutech Corporation, Ltd., 1-7-2 Aioicho, Sakata-shi, Yamagata 998-0032, Japan.
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Edura
authors.affiliation: Frontier Materials Research Department, Materials Research Laboratories, Nissan Chemical Industries, Ltd., 488-6 Suzumi-cho, Funabashi, Chiba 274-0052, Japan.
authors.forename: Juro
authors.initials: J
authors.lastname: Oshima
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395, Japan.
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Ishimatsu
authors.affiliation: Faculty of Science and Engineering, Waseda University 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan.
authors.forename: Miho
authors.initials: M
authors.lastname: Tsuwaki
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Imato
authors.affiliation: Faculty of Science and Engineering, Waseda University 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Shoji
authors.affiliation: Research Organization for Nano &Life Innovation, Waseda University, 513 Wasedatsurumakicho, Shinjuku, Tokyo 162-0041, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Mizuno