New technology for improved OLEDs

The Bayerische Patentallianz GmbH is selling a number of patents of the University of Regensburg to cynora GmbH. Thanks to the new Singlet-Harvesting technique and the use of newly developed emitter materials it will be possible to improve future OLEDs (organic light emitting diodes) and, in addition, produce large area displays in a cost efficient manner.

In future, OLEDs will be increasingly staking out market shares in display and lighting technology alongside conventional LEDs: OLEDs generate more brilliant images, are easier to manufacture, save more energy and can be produced in ultra-flat formats. Before this all becomes reality, however, a few developments will have to be advanced. At present, among other factors, the light emission (emission duration) of the light emitting molecules (emitter molecules) is too long, which results in undesirable saturation effects and thereby in energy losses, and represents a problem in the realization of favorably priced OLED lighting systems. The patents that cynora has acquired comprise a new technique for the generation of light emission and the use of innovative organic metal compounds. The latter are capable of reducing the emission duration of the emitter molecules and thereby improving the effectiveness of the OLEDs.

The new technique is referred to as singlet-harvesting and was developed by Prof. Dr. Hartmut Yersin from the Institute for Physical and Theoretical Chemistry at the University of Regensburg. With the help of this method it is possible to expediently combine the advantages of the so-called triplet and singlet states - these are the important light emitting states, thereby achieving a high light yield with lower saturation and energy losses.

The technique is enabled by the use of new, innovative metal-organic compounds that are considerably more cost efficient than conventional materials such as iridium or platinum and are also easier to process. "To date, OLED emitter materials were usually vaporized and had to be processed by way of a complex and cost intensive vacuum technology. The new metal compounds can be applied to the substrates, for example to ultra thin (<100 nm) and flexible carrier foils, with the help of our liquid processing in a more cost efficient manner. In this way, the new metal-organic compounds created by the University of Regensburg form the basis for new OLED technologies. In future, this will enable the production of ultra-flat as well as flexible displays with excellent color quality and high contrast. And this includes large area displays in connection with favorable manufacturing costs," as Dr. Thomas Baumann, managing director of cynora GmbH explained.