Manufacturing techniques and property evaluations of conductive elastic knits

Textiles can have valuable functions in terms of measurement, detection and communication when they are incorporated into functional electronic devices. However, the additional electric circuits limit the flexibility and extensibility, making the wearers uncomfortable and the manufacturing difficult. Therefore, in this study, conductive elastic knits are made of metallic yarns and expected to be used as wearable electronic textiles. In order to retain the flexibility of knits, a crochet machine with jacquard equipment is used to create knit patterns as electric circuits. Regardless of whether it is single-twisted yarn, double-twisted yarn, single-wrapped yarn, or double-wrapped yarn, the metallic wires can be completely covered in polyester filaments. Variations in twist numbers of conductive yarns or knit patterns are beneficial to the tensile strength with a maximum increment of 14%, and changing twist numbers of conductive yarns or knit patterns have a positive influence on the air permeability with a maximum increment of 24%. According to the results of the electric circuit stability test, using double-covered yarns ensures the knits a stabilized electric circuit regardless of the knit pattern.