This study uses metallic wires, stainless steel (SS) wires, and copper (Cu) wires as the core and 75 denier polyester (PET) fibers as the wrap material to form the metal/PET wrapped yarns. The optimal SS/PET and Cu/PET wrapped yarns are then made into different woven fabrics. The test results of the metallic wrapped yarns show that the optimal tenacity occurs with the wrapping count being 12 turns/cm, while the metal/ PET woven fabrics have a low surface resistivity due to the conductive metal/PET wrapped yarns along the weft direction. An increasing number of laminating layers increases the electromagnetic shielding effectiveness (EMSE) while decreasing the air permeability of the woven fabrics. The laminating angle is also proportional to the EMSE of the woven fabrics. In sum, the combination of metal wires and PET fibers provides the resulting woven fabrics with good EMSE.

Following technological advancements, there is a growing population of cellular phone and computer users. However, these electronic instruments cause electromagnetic waves, negatively influencing users’ health or precision instruments’ malfunction. Therefore, shielding electromagnetic wave becomes an important matter. In this study, stainless steel wires and bamboo charcoal roving are made into conductive yarn with 6 turns/cm by ring spinning machine. On a 14-gauge automatic horizontal knitting machine, the resulting yarn is then knitted into stainless steel/bamboo charcoal conductive fabrics and then evaluated for the electrical property and functions. According to experimental testing, electromagnetic shielding effectiveness (EMSE) of the fabrics increases with an increase in stainless steel content and number of lamination layers. In particular, when laminated at an angle of 0°/45°/90°/−45°/0°/45°, the fabrics have an EMSE of above 30 dB at an incident frequency between 2010 and 2445 MHz. The far infrared emissivity increases with bamboo charcoal content, reaching the maximum of 0.9 ɛ, when the fabric was made by one-cycle polyethylene terephthalate (PET)/stainless steel/bamboo charcoal plied yarn in the first feeder and four-cycle PET/bamboo charcoal plied yarn in the second feeder.

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In this study, bamboo charcoal/stainless steel (B/S) core-sheath yarns were made of stainless steel wires and bamboo charcoal polyester textured yarn using a rotor twister machine. The speed of rotor twister was from 7000 to 11000 rpm and the wrapped amount varied from 2 to 7 turns/cm. The tenacity of 3.08 g/d was obtained when the speed of rotor twister was 8000 rpm and wrapped amount was 4.0 turns/cm. The tensile strain of 24.9% was yielded when the speed of the rotor twister was 7000 rpm and the wrapped amount was 5.0 turns/cm. The laminated amount of the knitted fabrics varied from 1 to 6 layers. The far infrared ray emissivity of the knitted fabrics was 0.934 when the laminated amount was 2 layers and wrapped amount was 6 turns/cm. Finally, the optimum anion density of the knitted fabrics was 610 ions/cm3.

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