Water vapor transmission and electromagnetic shielding characteristics of stainless steel/viscose blended yarn woven fabrics

In this study, stainless steel/viscose blended yarn was prepared and different structured woven fabrics were prepared for studying the moisture transmission and electromagnetic shielding behaviour. By doubling viscose spun yarn with SS filament yarn, the SS/viscose blended yarn was prepared. The woven fabrics were made in a sample loom using viscose yarn and SS/viscose blended yarn. By changing the metal content, thread density and conductive fibre proportions at different levels, the developed fabrics were analyzed for maximum shielding effectiveness in the frequency of 300 kHz to 1.5 GHz. The fabric having conductive threads in warp and weft directions showed larger shielding effectiveness (SE) compared to fabric having conductive threads in one direction. The increase in weft density, proportions of conductive threads (in weft direction) and metal content increases the shielding level of fabric. The highest SE of 56 dB was observed for plain woven fabric compared to 3/1 twill, 2/2 twill and 2/2 basket fabrics in the frequency of 700 MHz. The influence of environmental factors such as relative humidity and pH on shielding behaviour of fabrics were also studied. As the relative humidity was increased, the SE was also increased. The fabric treated with acidic (or) basic condition exhibited better SE than the fabric in neutral condition. Similarly, air permeability and water vapour transmission characteristics of the developed conductive fabrics were also analyzed. The air permeability of the fabric was higher when the metal content in the fabric was low. The fabric having more floats showed higher air permeability compared to fabrics with less floats. Similarly, the water vapour transmission rate was also high for long float fabrics. The developed conductive fabrics could be used as wall covering and personal protective clothing in defense industry.