Professor Taek Seung Lee and Jongho Kim (Chungnam National University’s Department of Advanced Organic Materials and Textile System Engineering), and Professor Jin Sung-Ho and Park Juhyeon (Pusan National University’s Graduate Department of Chemical Materials, and Institute for Plastic Information and Energy Materials) authored a paper titled ‘Synthesis of conjugated, hyperbranched copolymers for tunable multicolor emissions in light-emitting diodes’. For 2015 June issue, Polymer Chemistry, published by the Royal Society of Chemistry, selected it as its back cover.
The paper discusses research of polymer material applied to solution process and explains that through polymer structure in the form of hyperbranched red, green, and blue monomers, diverse colors, including white, can be actualized depending on the amount of each monomer. Existing OLED lighting used R/G/B or YG/B stacking structure to produce white OLED, complicating the process. Although a method of producing white by combining R/G/B together is being developed, energy displacement between R/G/B can cause unwanted colors. However, if the R/G/B monomers can be introduced to polymer structure as hyperbranched forms as the paper suggests, the energy displacement can be minimized when the polymer solidifies which makes it easier for the colors to be realized.
Professor Lee revealed that hyperbranched polymer materials were used in the research and that as white can be produced from just one polymer material, simple process can be used for the production.
The patent for this technology has been applied (application number 10-2012-0091350) in Korea. It is anticipated that this will become a key technology for reducing the next generation OLED lighting production cost.