Concept of heat-induced inkless eco-printing

► Heat-induced, inkless eco-printing (HIEP) does not require ink or toner. ► The mechanism and its feasibility of HIEP are discussed. ► Printing text is formed on a paper via yellowing/blacking due to thermal energy. ► The innovative concept of HIEP is proposed for the first time. ► This research provides for the development of related interdisciplinary research.