Plastic - Page 9

Victrex and the Holst Centre presented progress in flexible substrate development based on Victrex's APTIV PEEK polymer film. The results are promising and Victrex decided to step into a full partnership with the Holst Centre. Victrex's material can withstand high processing temperatures in comparison with other thermoplastic materials, and can be used as a substrate for flexible and printed electronics such as OLED.

Specifically, enhancements were applied during the manufacturing process of APTIV PEEK film in order to fulfill the dimensional stability requirements of flexible substrates used in plastic electronics applications. In the study, the performance of the APTIV flexible electronics grade was compared to that of the standard extruded APTIV film along with other competing candidate films. Critical performance parameters were measured, such as the coefficient of thermal expansion, thermo mechanical properties and dimensional stability, mostly at up to 230ºC.

Plastic Logic announced a major investment from Russia's RUSNANO. The $700 million (!) investment will be used to build a mass-production factory for thin, light and flexible plastic-based e-paper displays. Those displays will be used in Plastic Logic’s first commercial consumer electronics product, a next-generation electronic reader for business that is currently under development.

The new factory will be built in Zelenograd, Russia, and is scheduled to begin production in 2013/2014 - and will be able to produce hundreds of thousands displays monthly. This will be Plastic Logic's second factory (the first one was opened in 2008 in Dresden, Germany). Russia hopes that this move will establish a commercial plastic electronics industry.

The Flexible Display Center (FDC) at Arizona State University and AU-Optronics will co-develop mixed oxide thin film transistors (TFTs) for flexible AMOLED displays. AUO and the FDC will work in active partnership with dedicated engineering teams to advance mixed oxide transistor technology and the handling capabilities of conventional flat panel display (FPD) manufacturing processes to accommodate the thin, plastic substrates used for AMOLED flexible displays. Mixed oxide TFTs offer a better ability to drive currents and improve the lifetime and stability of transistors used for OLED displays.

Flexible AMOLED by ITRI

AUO is also working towards flexible displays together with Taiwan's ITRI. AUO plans to start mass producing AMOLED displays in Q2 2011 (but these will not be flexible...).

Samsung plans to launch new AMOLEDs on a plastic substrate within two years. They say that these new AMOLEDs will be 'unbreakable'. They will also be lighter, safer and thinner. These qualities can be useful in mobile phone displays, which will allow Samsung to keep their AMOLED price premium in these years. Samsung plans to place a TFT on the plastic panel and to replace the existing vinyl protection sheet with PI (polyimide) film to avoid residue upon light emission.

Samsung revealed flexible, unbreakable AMOLED prototypes back in 2009, see video above.

The Printable Electronics Technology Centre (PETEC) has announced plans for a new prototyping line to support the lighting and Organic Photovoltaic sectors. The new line is targeted at industries needing large area coating capability alongside the need for reproducible uniform and low defectivity thin film coating onto glass and plastic substrates.

It is designed to be an automated batch tool based on cassette handling of samples to minimise manual intervention. The specification has been aligned with the needs of the SSL and PV industry. It will produce up to 20 samples per day with a panel size from 100mm to 200mm square. The line will have slot-die and spin coating modules, metal and organic evaporation and encapsulation.  It will enable the deposition of solution and small molecule OLED material technologies. It will target fine coating active layers of 10-200nm thinness with uniformity of +-5% across the full panel width.

Last week we reported that PolyPhotonix plans to launch a 8" 60lm/W OLED Lighting panel. They will be using this line at PETEC.

The Flexible Display Center (FDC) at Arizona State University announced that Sunic System has become an industry partner in the center. The FDC, together with Sunic, will develop flexible OLED displays. The FDC has purchased a Gen-II OLED SUNICEL Plus 400 vacuum evaporation and encapsulation process tool from Sunic for its Tempe development facility.The tool will be installed in the fall (2010), with first devices anticipated in 1Q 2011.

The SUNICEL Plus system is designed to simplify OLED technology development and manufacturing, and is equipped to handle plastic substrates without interrupting the vacuum process. The system enables full color AMOLED and mono-color panel production with high electro luminescence (EL) performance and long lifetime.

InnoPhysics has performed successful feasibility studies at the Holst Centre, and now is ready to go to market with its proprietary Digital-on-Demand PlasmaPrint hardware solution. They say that their technology enables software patterned surface functionalization, etching and deposition of functional coatings on thin (plastic) substrates.

Plasma-printed OLED lighting test structures

The proprietary InnoPhysics technology solution operates on a large variety of plastic substrates in ambient conditions, at room temperature and it provides flexibility in patterning, i.e. mask-less. As part of the go-to-market strategy, InnoPhysics is developing a PlasmaPrint toolkit integratable with existing table-top R&D print platforms.

The Holst Centre and NeoDec will partner on metallic inks for flexible electronics. NeoDec's conductive ink technology is a complementary technology to the competences of Holst Centre and its industrial
partners and opens new routes to enable roll-to-roll manufacturing of flexible electronic devices such as OLED lighting foils. The partnership will initially run for 2 years, and NeoDec's technology will be further developed within the Holst Centre.

Printed structures from the Holst Centre

The Holst Centre has released a new proprietary roll-to-roll (R2R) sintering platform for fast and low-temperature curing of printed conductive structures. The center is progressing towards a complete tool set for R2R manufacturing and can be used for plastic electronics such as flexible OLEDs, organic PV solar cells and more. Holst' line now includes printing, coating, drying and lamination stages in addition to the new sintering unit. A vacuum deposition stage is currently in development.

Screen printed structures on foil photo

High web speeds and low temperatures are key elements for R2R manufacturing of plastic electronics. The sintering platform uses a new photonic sintering process, developed by Holst Centre, which heats only the printed target material rather than the whole carrier substrate. The tool can sinter printed conductive structures in less than a second, which is already enabling a fast throughput speed of over 5 meters/minute. It also works at significantly lower temperatures than traditional sintering techniques, preventing distortion of the carrier substrates and reducing energy costs.

Researchers at Stanford University have successfully developed a brand new concept of OLEDs with a few nanometer of graphene as transparent conductor. This paved the way for inexpensive mass production of OLEDs on large-area low-cost flexible plastic substrate, which could be rolled up like wallpaper and virtually applied to anywhere you want. The researchers say that Graphene has the potential to be transparent, high-performance, highly conductive and cheaper by several orders of magnitude than current ITO based solutions. Interestingly just a few weeks ago we reported that Graphene can be used to make organic lighting devices, too.

Graphene OLED

Traditionally, indium tin oxide (ITO) is used in OLEDs, but indium is rare, expensive and difficult to recycle. Scientists have been actively searching for an alternative candidate.

The next generation of optoelectronic devices requires transparent conductive electrodes to be lightweight, flexible, cheap, environmental attractive, and compatible with large-scale manufacturing methods. Graphene (a single layer of graphite) is becoming a very promising candidate due to its unique electrical and optical properties. Very recently, Junbo Wu et al., researchers at Stanford University, successfully demonstrated the application of graphene in OLEDs for the first time.