Facile and scalable fabrication process of electroluminescent filament with high luminescent efficiency

Electroluminescent (EL) filament has received much more attention on the application of smart and displayable textiles. In this work, the co-axial wet-spinning method was utilized to prepare a core/sheath filament with a copper wire as core electrode and thermal polyurethane (TPU) contained EL material of ZnS:Cu as sheath. The outside was wire-winded helically and then was coated with silver coating via magnetron sputtering, which was used as the other electrode. About 10 nm thickness silver coating was afforded after 90 s sputtering, which ensured Ag coating continuity. Finally, the filament was immersed into a waterborne polyurethane (WPU) emulsion to endow a transparent protective layer. When the ratio of Zn:S/TPU was 1:1, the as-obtained EL filament exhibited the highest luminescent efficiency. This strategy made almost all EL materials excited, which provided a promising and facilely scalable method to fabricate EL filament with high utilization rate of EL materials and luminescent efficiency.