Two different emitting compounds, 1-[1,1;3,1]Terphenyl-5-yl-6-(10-[1,1;3,1]terphenyl-5-ylanthracen-9-yl)-pyrene (TP-AP-TP) and Poly-phenylene vinylene derivative (PDY 132) were used to white OLED device. By incorporating adjacent blue and yellow emitting layers in a multi-layered structure, highly efficient white emission has been attained. The device was fabricated with a hybrid configuration structure: ITO/PEDOT (40 nm)/PDY-132 (8∼50 nm)/NPB (10 nm)/TP-AP-TP (30 nm)/Alq3 (20 nm)/LiF (1 nm)/Al (200 nm). After fixing TP-AP-TP thickness of 30 nm by evaporation, PDY-132 thickness varied with 8, 15, 35, and 50 nm by spin coating in device. The luminance efficiency of the white devices at 10 mA/cm2 were 2.93 cd/A∼6.55 cd/A. One of white devices showed 6.55 cd/A and white color of (0.290, 0.331).
Metachromatic properties of admixture of methylene blue(MB) and thionine in aqueous solution has been studied by fluorescence spectroscopy. In spite of nonfluorescence character has been MB itself, mixing MB to monomeric concentration of thionine, new coaggregation band has been formed in shorter wave length than fluorescence of thionine because of MB was redistributed to thionine aggregate. It suggested that coaggregate of MB and thionine were more tightly formed than the each dye aggregate.