Modeling and Validating Analytic Relations for Electromagnetic Shielding Effectiveness of Fabrics with Conductive Yarns

Electromagnetic (EM) radiation may be harmful for human’s health and for functioning of electronic equipment. The field of Electromagnetic Compatibility approaches various solutions to tackle this problem, while shielding of the radiation is one of the main solutions. Since the development of spinning technology for producing conductive yarns for fabrics, textile electromagnetic shields have become a valuable alternative to metallic shields. Their main advantages are given by the flexibility, the low weight and the good mechanical resistance, as well as by the possibility to precisely design the shield. The scientific literature includes several analytic relations for estimating the electromagnetic shielding effectiveness (EMSE), in case of woven fabrics with conductive yarns, which may be modeled as a grid of electric conductors. This book chapter tackles three different analytic models for estimating EMSE, which are useful to predict this functionality in the design phase of fabrics. The analytic relations are subsequently comparatively validated by EMSE measurements via TEM cell equipment of two woven fabrics with conductive yarns out of stainless steel and silver with a grid of 4 mm. Results of validated analytic relations are used for the approach of designing textile shields with regard to final application requirements

Life Cycle Assessment of Flexible Electromagnetic Shields

Nowadays, fiber based flexible electromagnetic shields have widespread applications in ensuring Electromagnetic Compatibility (EMC). Shielding is a solution of EMC, and the main methods to estimate shielding effectiveness are represented by the circuit method and the impedance method. Magnetron sputtering of metallic layers represents a novel technique to impart electric conductive properties to fabrics. Coating of fabrics represents a second main option to manufacture textile shields beside the insertion of conductive yarns in the fabric structure. Life Cycle Assessment (LCA) is often used to assess a comparatively modern with a classical manufacturing process in order to prove its eco-friendly character. This chapter comparatively assesses flexible EM shields manufactured of fabrics with inserted conductive yarns with and without magnetron plasma coating. The copper plasma coating of cotton fabrics with inserted silver yarns increases shielding effectiveness (EMSE) by 8–10 dB. In order to keep for the LCA study the same functional unit of 50 dB at 100 MHz for one sqm of fabric, the fabric structure is modeled with a reduced distance between the inserted conductive yarns. Results of the LCA study show a substantial impact on the environment for the plasma coated fabric upon using a laboratory scale deposition set-up

Smart textiles to promote multidisciplinary stem training

Smart textiles consist of multi-disciplinary knowledge. Disciplines such as physics, mathematics, material science or electrics is needed in order to be able to design and manufacture a smart textiles product. This is why knowledge in smart textiles may be used to showcase high school and university students in basic years of preparation some applications of technical disciplines they are learning. The Erasmus+ project “Smart textiles for STEM training – Skills4Smartex” is a strategic partnership project for Vocational Education and Training aiming to promote additional knowledge and skills for trainees in technical fields, for a broader understanding of interconnections and application of STEM, via smart textiles. Skills4Smartex is an ongoing project within the period Oct. 2018-Sept. 2020, with a partnership of six research providers in textiles www.skills4smartex.eu. The project has three intellectual outputs: the Guide for smart practices (O1), the Course in smart textiles (O2) and the Dedicated e-learning Instrument (O3). The Guide for smart practices consists in the analysis of a survey with 63 textile companies on partnership level and interviews with 18 companies. Main aim of O1 is to transfer from source site to target sites technical and smart textile best practices and the profile of workforce needed for the future textile industry. The needs analysis achieved within O1will serve to conceive the Course for smart textiles with 42 modules (O2), to be accessed via the Dedicated e-learning Instrument (O3). All outputs are available with free access on the e-learning platform: www.adva2tex.eu/portal

The Improvement of the Resistance to Candida albicans

This paper presents the improvement of the antimicrobial character of woven fabrics based on cotton. The woven fabrics were cleaned in oxygen plasma and treated by padding with silver chloride and titanium dioxide particles. The existence of silver and titanium on woven fabrics was evidenced by electronic microscope images (SEM, EDAX) and by flame atomic absorption spectrophotometry. The antimicrobial tests were performed with two fungi: Candida albicans and Trichophyton interdigitale. The obtained antimicrobial effect was considerably higher compared to the raw fabrics. Treatment of dyed fabrics with a colloidal solution based on silver chloride and titanium dioxide particles does not considerably influence colour resistance of dyes

Modelling the Woven Structures with Inserted Conductive Yarns Coated with Magnetron Plasma and Testing Their Shielding Effectiveness

The paper proposes the analytic modelling of flexible textile shields made of fabrics with inserted conductive yarns and metallic plasma coating in order to calculate their electromagnetic shielding effectiveness (EMSE). This manufacturing process is highly innovative, since copper plasma coating improves EMSE on the fabrics with inserted conductive yarns of stainless steel and silver with 10–15 dB in the frequency range of 0.1–1000 MHz, as shown by the measured EMSE values determined according to the standard ASTM ES-07 via the Transverse Electromagnetic (TEM) cell. On the other hand, modelling of EMSE for such conductive flexible shields gives an insight on estimating EMSE in the design phase of manufacturing the shield, based on its geometric and electrical parameters. An analytic model was proposed based on the sum of EMSE of the fabric with inserted conductive yarns and EMSE of the copper coating. The measurement results show close values to the proposed analytic model, especially in case of fabric with conductive yarns having stainless steel content

Improving the textile\u27s enterprises knowledge matrix

The textile enterprises need adequate solutions to face the competition on the global market. Innovation leverages the enterprises competitiveness: however, improving innovation is a task of research providers in the field. The Knowledge Matrix for Innovation (KMI) represents an instrument for quantifying the intangible assets of a textile enterprise. Examples of intangible assets are: innovation strategy / culture, informational resources, training methodology, relationships portfolio, IP rights etc. By improving such factors of the KMI, the textile enterprises are going to improve their competitiveness. This main aim is tackled by the Erasmus Plus – VET Project “Matrix of knowledge for innovation and competitiveness in textile enterprises - TexMatrix” (2016-2018). The red line of the project follows the definition of the KMI, the adaptation of the Benchmarking questionnaire and its implementation on the e-learning Tool, the Benchmarking study by consulting of 50 textile enterprises at consortium level, supporting the Guide with new research and innovation management solutions for the enterprises and Blended courses for 95 young trainees, based on the Guide in e-learning format. The project also aims to counsel 100 decision-factors from textile enterprises on the new solutions comprised in the Guide, within 5 Workshops. The e-learning Tool has the URL address: www.advan2tex.eu/portal/