This paper investigates a textile material of low surface mass for its protection against electromagnetic radiation (EMR), which is suitable for composite structures of garments, and for technical and interior applications. The shielding effectiveness against EMR of fabric knitted from polyamide threads coated with silver, measured in the frequency range of 0.9 GHz to 2.4 GHz, indicated a high degree of protection. The key contribution of the paper is the evaluation of the stability of the shielding properties against EM radiation after applying apolar and polar solvents, in synergy with the cyclic process parameters of wet and dry cleaning. The results of the study confirmed the decline in the shielding effectiveness after successive cycles of material treatment with dry and wet cleaning. The effect of wet cleaning in relation to dry cleaning is more apparent, which is due to the damage of the silver coating on the polyamide threads in the knitted fabric.

Electromagnetic interference (EMI) have become very serious in a variety of different electronic equipments, such as personal computers (frequency at several GHz), mobile devices (0.9 – 2.4 GHz) and similar. This imposes the need for setting boundaries for EM emission of electric and electronic devices in order to minimize the possibility of interference with radio and wireless communications. Functional textiles can offer protective properties against EM radiation. The aim of this study is to investigate the degree of protection against EM radiation provided by polyamide copper-coated interlining fabric before and after dry cleaning treatment. EM protection efficiency of the interlining functional fabric is explored on both sides at the frequencies of 0.9; 1.8; 2.1 and 2.4 GHz. The results obtained have shown that the interlining fabric has good protective properties against EM radiation, but after dry cleaning, treatment reduction is observed. Scanning electron microscopy micrographs of the interlining surface confirms shield effect decline due to degradation and firing of the copper layers during the process of dry cleaning.

The paper investigates the shielding effectiveness of a newly developed cotton and polyester fabric into which conductive stainless-steel threads were incorporated in the warp and weft directions at frequencies 0.9 GHz, 1.8 GHz, 2.1 GHz, and 2.4 GHz. As resistance to external influences and degradation is an additional critical factor for protective textiles, the newly developed protective fabric was exposed to cumulative wash cycles with liquid and powder detergents, which were targeted to preserve the shielding effectiveness (SE). In addition to the SE shielding effectiveness, the influence of 10 washing cycles on the change in thickness as a structural parameter was analyzed. Micro-images of fabric surfaces before and after the first, third, fifth, seventh, and tenth washing cycles were also observed. The obtained results showed that powder and liquid detergents were well formulated to preserve the electromagnetic shielding effectiveness (EMSE) at higher frequencies. However, their impact on the appearance of the surface was not fully consistent with the shielding effectiveness.

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The electromagnetic (EM) protection factor is defined as a ratio of EM field intensity measured without the shielding material and field intensity with the shielding material placed between EM radiation source and receiver. This research is focused on SE durability of the composite cloth structure, where the functional interlining polyamide fabric coated with copper IF was integrated, after exposure to heat and moisture in steam-setting, ironing and double compressing. The cloth composite structure was also exposed to solvent in dry cleaning. It was proved that a synergy of thermal and mechanical actions in ironing and pressing caused a drop of SE in the frequency range from 0.9 to 2.4 GHz. Increased number of dry cleaning cycles resulted in further reduction of protective properties. Cross section and chemical analysis of IF before and after 10 dry cleaning cycles are not harmonized with low durability of SE properties in dry cleaning.