News Article | June 1, 2015
DuPont Displays (DuPont) and leading inkjet equipment manufacturer Kateeva announced today that they will join forces to develop optimized inks, equipment, and processes to further advance inkjet printing technology for Organic Light Emitting Diode (OLED) display devices. The companies will work closely to leverage DuPont technical leadership in solution materials for printed OLED devices with Kateeva’s exclusive YIELDjet™ inkjet printing platform. The aim of this cooperation is to establish a proven, cohesive offering for OLED device manufacturers that enables a simpler yet highly effective process for manufacturing OLED TV displays using inkjet technology. “DuPont is focused on providing best-in-class OLED materials and technology to help large format OLED TVs achieve mass commercialization,” said Avi Avula, global business director, DuPont Displays. “We expect that our collaboration with Kateeva will streamline the decision making process for device and display makers and enable them to successfully manufacture printed OLED devices, at scale, sooner.” The DuPont and Kateeva cooperation is non-exclusive and manufacturers will not be restricted in their choice of equipment or materials through this effort; it will only aim to increase viable, manufacturing-ready options. The companies expect to provide cross-referenced data for DuPont materials with Kateeva printing equipment. The OLED industry is collectively working towards mass production of OLED TVs using soluble OLED materials to economically produce high-performance displays while dramatically reducing the material waste associated with current evaporative processes. Historically, device performance using soluble production has lagged. “With Kateeva and DuPont combining their considerable expertise in inkjet printing and OLED materials, the industry is poised to take a significant step forward in achieving low cost mass production of OLED TV,” said Steven Van Slyke, chief technology officer at Kateeva. Kateeva’s YIELDjet platform offers OLED manufacturers a mass-production equipment solution with dramatically lower cost-of-ownership advantages than the vacuum evaporation technologies currently used to pattern red, green and blue (RGB) OLED pixels. This vacuum-based RGB patterning process is one of the critical barriers to the realization of low-cost OLED TV mass production. Thanks to a novel architecture and unique technologies, the YIELDjet platform helps manufacturers maximize OLED device lifetime and quality, while also offering ultra-low particle performance, consistent process reliability, and high uptime. Kateeva makes breakthrough production equipment for manufacturers of advanced electronics technologies. The company has pioneered a precision deposition technology platform that uses innovative inkjet printing to deposit coatings on complex applications with blinding speed and superb accuracy. Technology leaders use Kateeva’s solution to enable cost-effective mass-production of flexible and large-size OLED displays, among other products. Kateeva is headquartered in Newark, Calif., maintains operations in Korea, China and Taiwan, and is backed by leading venture capital firms and other investors. For more information, please visit http://www.kateeva.com. DuPont Displays brings more than 15 years of experience in enabling evaporative and solution-based OLED technologies through advanced materials that deliver the color, efficiency, and lifetime performance that display manufacturers and consumers demand. DuPont offers highly engineered, next-generation OLED materials as well as solution process know-how that is making the promise of lower cost OLED technology commercially feasible for TVs and other large-format displays. DuPont (NYSE: DD) has been bringing world-class science and engineering to the global marketplace in the form of innovative products, materials, and services since 1802. The company believes that by collaborating with customers, governments, NGOs, and thought leaders we can help find solutions to such global challenges as providing enough healthy food for people everywhere, decreasing dependence on fossil fuels, and protecting life and the environment. For additional information about DuPont and its commitment to inclusive innovation, please visit http://www.dupont.com. The DuPont Oval Logo and DuPont™ are registered trademarks or trademarks of DuPont or its affiliates.
Kim S.-Y.,Organic Light Emitting Diode |
Kim J.-J.,Organic Light Emitting Diode
Organic Electronics: physics, materials, applications
Outcoupling efficiencies (OCEs) of green phosphorescent organic light emitting diodes (OLEDs) with graphene anodes are theoretically analyzed using the classical electromagnetic model and are compared with the OLEDs with ITO anodes. The OCEs of the OLEDs with anodes of 3 or 4 graphene monolayers are comparable to an ITO based device with a 150 nm thick ITO, where both electrodes have a similar sheet resistance of about 24Ω/□. However, the OCEs of graphene based OLEDs are lower than that for ITO based devices with a same sheet resistance in most cases. This limitation can be overcome by using a graphene/transparent conducting oxide (ITO or IZO) composite electrode, which can achieve high outcoupling efficiency, low sheet resistance and high transmittance at the same time. In addition to that, the light extraction techniques are expected to be much more effective in graphene based OLEDs than ITO based OLEDs, which is important for lighting application of OLEDs. © 2012 Elsevier B.V. All rights reserved. Source
News Article | October 28, 2015
Workrite Ergonomics this week announced the launch of a new task light, the Natural, featuring OLED technology from LG Chem. OLED is an Organic Light Emitting Diode in which the electroluminescent layer is a film of organic compound that emits light in response to an electric current. OLED panels are slim, lightweight & glare free, making them the perfect choice for unique and innovative office lighting. As a global leader in OLED lighting, LG Chem’s diverse panel portfolio, superior performance and strong supply chain made them a clear choice for Workrite when selecting an OLED panel partner. “Natural provides rich, evenly diffused light across the work surface and renders color with amazing accuracy.” said Darren S. Hulsey, Product Manager at Workrite Ergonomics. “The OLED panel in Natural produces a neutral white light that creates no glare, is completely free of UV, and emits no blue light risk that can negatively affect the circadian rhythm of user’s bodies.” The use of OLED in task lighting can help eliminate a variety of health risks currently associated with artificial lighting and enables people in reading intensive environments to work in complete comfort for long periods of time. OLED panels also produce very little heat (<35°C/95°F) resulting in products that have little impact on ambient temperatures in the work environment and are safe to touch, even after hours of operation. “Natural not only features leading edge OLED technology, it has a very distinct, modern design that is unlike anything else on the market.” said Charlie Lawrence, President of Workrite. “Our partnership with LG Chem and the introduction of Natural are perfect examples of why progressive companies around the world continue to look to Workrite for innovative office solutions.” Workrite will begin shipping Natural in November and expects it to be extremely popular with the design community and end-users alike. Workrite Ergonomics was founded in 1991 and is an internationally recognized industry leader in design, manufacturing and distribution of height-adjustable workcenters and ergonomic office accessories, including adjustable keyboard platform systems, flat panel monitor support systems, and task lighting. The company is based in Petaluma, California and is represented across the United States and Canada by a broad network of highly professional sales associates. For more information on Workrite Ergonomics’ products, please visit Workrite Ergonomics. LG Chem, located in Seoul, South Korea, is an OLED light panel manufacturer which provides OLED light panels in a variety of shapes and sizes. Ten different models are available with two different color temperatures, which deliver high color rendering levels as well as achieving high luminance, high efficacy and long lifespan. For more information, please visit LG Chem.
Lee S.,Organic Light Emitting Diode |
Lee S.,Samsung |
Kim K.-H.,Organic Light Emitting Diode |
Limbach D.,University Mainz |
And 2 more authors.
Advanced Functional Materials
An exciplex forming co-host is introduced in order to fabricate orange organic light-emitting diodes (OLEDs) with high efficiency, low driving voltage and an extremely low efficiency roll-off, by the co-doping of green and red emitting phosphorescence dyes in the host. The orange OLEDs achieves a low turn-on voltage of 2.4 V, which is equivalent to the triplet energy gap of the phosphorescent-green emitting dopant, and a very high external quantum efficiency (EQE) of 25.0%. Moreover, the OLEDs show low efficiency roll-off with an EQE of over 21% at 10 000 cdm-2. The device displays a very good orange color (CIE of (0.501, 0.478) at 1000 cdm-2) with very little color shift with increasing luminance. The transient electroluminescence of the OLEDs indicate that both energy transfer and direct charge trapping takes place in the devices. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
Lee S.,Organic Light Emitting Diode |
Lee J.-H.,Organic Light Emitting Diode |
Kim J.-J.,Organic Light Emitting Diode |
Advanced Functional Materials
The rate-limiting step of charge generation in charge-generation units (CGUs) composed of a p-doped hole-transporting layer (p-HTL), 1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile (HATCN) and n-doped electron-transporting layer (n-ETL), where 1,1-bis-(4-bis(4-methyl-phenyl)- amino-phenyl)-cyclohexane (TAPC) was used as the HTL is reported. Energy level alignment determined by the capacitance-voltage (C-V) measurements and the current density-voltage characteristics of the structure clearly show that the electron injection at the HATCN/n-ETL junction limits the charge generation in the CGUs rather than charge generation itself at the p-HTL/HATCN junction. Consequently, the CGUs with 30 mol% Rb 2CO 3-doped 4,7-diphenyl-1,10-phenanthroline (BPhen) formed with the HATCN layer generates charges very efficiently and the excess voltage required to generate the current density of Â±10 mA cm -2 is around 0.17 V, which is extremely small compared with the literature values reported to date. The rate limiting step of charge generation in the charge-generation units (CGUs) composed of a p-doped hole-transporting layer (HTL)/1,4,5,8,9,11- hexaazatriphenylene hexacarbonitrile (HATCN)/n-doped electron-transporting layer (ETL) is reported. Energy level alignment and the current density-voltage characteristics of the structure show that the electron injection at the HATCN/n-ETL junction limits the charge generation in the CGUs. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source