Showa Denko K.K. (SDK) and the Science and Technical Research Laboratories of Japan Broadcasting Corporation have jointly developed a new type of phosphorescent polymer for use in flexible displays.
Until now,, only fluorescent-polymer-based devices, whose theoretical luminous efficiency is 5% maximum, have been used in display devices. However, organic electroluminescent devices that use the newly developed phosphorescent polymer will theoretically be able to attain a maximum luminous efficiency of 20% in the three primary colours.
Phosphorescence is usually observed at very low temperature (-196°C) and rarely seen at ordinary temperature. Nevertheless, the newly developed polymer can emit phosphorescence at ordinary temperature with high efficiency.
Better yet, ink jet printing methods can be used to produce large-screen, high-precision displays using the new material.
Development efforts will focus on improving the blue colour and achievement of the 20% luminous efficiency for the three colours.