This paper reports low-voltage and high power efficiency blue fluorescent organic light-emitting diodes (FLOLEDs) using 4,4 -bis [4-(di-4-tolylamino)styryl]biphenyl (DPAVBi) as a fluorescent dye and 9,10-di(naphth-2-yl)anthracene (ADN) as a host. We studied the effect of using 1, 1-bis{4-[N,N-di(p-tolyl)amino]-phenyl}cyclohexane (TAPC) as an exciton blocking layer in the blue FLOLEDs, and found the formation of electromers in TAPC at high current density. Based on the efforts toward high power efficiency and stability, we fabricated the blue FLOLEDs exhibiting low driving voltages of 2.9 V for 100 cd m −2 and 3.6 V for 1000 cd m −2 , a maximum luminance of 43256 cd m −2 at 6.6 V, and a high power efficiency of 9.7 lm W −1 with reduced efficiency roll-off.Since Tang and Van Slyke reported the first electroluminescence from organic thin films, 1 organic light-emitting diodes (OLEDs) have been in the spotlight as the next-generation display and lighting devices. Both academic and industrial research for the advances in material science, device physics and fabrication process enabled OLEDs to be realized as the main display device in state-of-the-art mobile items and televisions. Despite this, there is room for improving the performance of OLEDs, particularly for blue-emitting devices. The performance of blue OLEDs is generally inferior to that of the other colors in terms of the efficiency and driving voltage, mainly due to the wide bandgap. Therefore, the development of low-voltage and efficient blue-emitting OLEDs is one of the most important issues for the development of OLEDs.Recent research on blue OLEDs has focused more on improving the performance of phosphorescent OLEDs (PHOLEDs) rather than fluorescent OLEDs (FLOLEDs). It is apparent that PHOLEDs have intrinsically higher internal quantum efficiency (IQE) compared to FLOLEDs through the radiative recombination of triplet excitons, but they generally have a short life-time and emit sky-blue colors, which limits the genuine blue color and wide color gamut in display devices. 2 In addition, for blue PHOLEDs, additional functional organic layers are essential to achieve a high efficiency such as an exciton-blocking layer (EBL) or a hole-blocking layer (HBL) with wide bandgap materials, resulting in a high driving voltage and a complicated device structure. For those reasons, commercial OLED panels typically use the fluorescence OLEDs for blue emission, combined with red and green PHOLEDs. Therefore, it is important to develop high-efficiency and low-voltage blue OLEDs based on fluorescent materials and examine their device physics.Over the past year, several research groups have reported high external quantum efficiencies (EQEs) over 10% in blue FLOLEDs based on novel materials. 3-5 Although new materials outperforming the conventional hosts and dopants have been synthesized continuously, only a few have been used widely for further research. Therefore, a study of blue FLOLEDs using commercially available materials is meaningful for generalizing the device phys...

Highly conductive, solution-processed silver thin-films were obtained at a low sintering temperature of 100 °C in a short sintering time of 10 min by introducing oximes as a potential reductant for silver complex. The thermal properties and reducibility of three kinds of oximes, acetone oxime, 2-butanone oxime, and one dimethylglyoxime, were investigated as a reducing agent, and we found that the thermal decomposition product of oximes (ketones) accelerated the conversion of silver complex into highly conductive silver at low sintering temperature in a short time. Using the acetone oxime, the silver thin-film exhibited the lowest surface resistance (0.91 Ω sq(-1)) compared to those sing other oximes. The silver thin-film also showed a high reflectance of 97.8%, which is comparable to evaporated silver films. We also demonstrated inkjet printed silver patterns with the oxime-added silver complex inks.