Much effort is being directed at developing wearable devices because they offer the potential combination of real-time personal communication and convenient portability. In this sense, communicative textiles that can sense and respond to changes in their environment, that is, smart textiles, are attracting attention because they are easy to integrate into the human body. In particular, light-emitting textiles are preferred for high-visibility outfits for personal safety and attractive signaling that enable mutual recognition or new forms of communication. However, most light-emitting textiles, including weavable optical fibers and fiber-shaped electroluminescent devices, require electric power supply. This paper presents a mechanoluminescent fiber that is capable of emitting light and can potentially be powered just by human motions, such as body movement and muscle stretching, instead of a battery. This is achieved by utilizing a robust mechanoluminescent (ML) fiber developed by improving the binding of mechanoluminescent ZnS-embedded-polydimethylsiloxane with a primer-treated cross-shaped fiber frame and employing an adhesive layer. A novel ML fabric, created by weaving ML fibers, is also presented, which is applicable to wearable light-emitting fabrics. Battery-free, human motion-powered ML fiber is expected to make environmentally friendly and sustainable light, and further paves the way for new wearable devices that reduce energy waste.
