Possible applications of metallised textiles in high frequency and EMC.

Possible applications of metallised textiles in high frequency and EMC.

Metallised textiles have been used in a wide range of technical applications for more than 50 years. Innovative applications can be found not only in high-frequency technology and sensor technology, but also in Electromagnetic compatibility (EMC) and in various market segments such as the automotive industry, medicine, and care and even aerospace.

?1 Metallised yarns and fabrics

In a wet-chemical process, the polymers nylon (PA6.6) and perlon (PA6) are coated with 99.9% pure silver as technical textiles. The individual yarns as monofilaments, multifilament and flat goods thus become electrically conductive components. The physical anchoring and the ductility of the silver lead to a unique hybrid structure, which can be used as a robust and flexible conductor. The fabrics can be coated in various textile constructions. To achieve a higher electrical surface conductivity, they can then be further refined with the help of electroplating.

Picture: Metallised Fabrics (a) in knitted and (b) woven and (c) non-woven form

2 Application of metallised textiles in RF technology and EMC

Textile-based antenna structures [1], [2] can be sewn, embroidered, or woven from the yarns mentioned in the field of high-frequency technology from 0.3 - 3 GHz. The aforementioned structures are also successfully worked out of metallised flat goods [3]. In the field of electromobility, the refined flat goods can be used for electromagnetic cable shielding with weight savings [4]. Whether electromagnetic shielding in architectural spaces or mobile, large volume shielding solutions in the form of textile shielding cabins (shielding tents), metallised textiles offer the highest flexibility in material as well as application in the measurement and test field. In the field of pre-compliance testing, these tents offer a flexible and budget-oriented solution for numerous industries. As shown in Figure 2 (a), the respective technical requirements could be successfully fulfilled with the metallised textiles in the Galileo project (ESA) as well as in Figure 2 (b) of the Mars Rover program (NASA) [5]. For investigations on the influence of the electromagnetic boundary conditions on the radiation behavior of vehicle antennas, as shown in Figure 2 (c), a light, artificial ground plane could be flexibly stretched under the vehicle with the help of the metallised flat fabric [6].

Picture: Shieldex? Shielding Enclosure - Galileo project (ESA)

Picture.: Shieldex? Shielding Enclosure - Mars rover program (NASA).

Realized by Shieldex US.

Picture: Textile ground plane for measuring vehicle antennas.

In the application field of logistics, textile shielding curtains with the RFID frequencies 13.56 as well as 900 MHz for mobile warehouse management offer electromagnetic shielding in order to be able to guarantee a secure and error-free reading and writing process to the individual transponders. In the field of law enforcement and the military, as well as for protection against espionage and hacker attacks, textile solutions in the form of shielding bags meet the high technical security requirements. In this way, unwanted external access to mobile end devices can be prevented and protected by the metallised textiles as part of forensic evidence preservation.

Welcome to Shieldex, the leading manufacturer of metallized textiles

Shieldex is the worldwide market leader in the metallized fabrics industry. Founded in 1978, its family run headquarter and production site is located in Bremen, Germany. The metallisation of polyamide yarns, textiles, fabrics, nonwovens, and PA-components is our core business. We exclusively use silver with a purity of at least 99% to ensure the best standard of quality, which is represented by our various certificates. Our combination of polyamide and noble metals such as silver, copper, tin, and nickel offer the possibility of a multifunctional application in various fields. Our development department supports customer specific ideas our products for individual solutions. Feel free to contact us! We are eager to find intelligent, efficient, and future-oriented solutions with you and for your applications.

Company profile:

Shieldex - Statex Produktions- und Vertriebs GmbH

Kleiner Ort 9-11

28357 Bremen

Germany

Tel. +49 421 275047

Website: www.shieldex.de/en

List of references

[1] Z. Wang, J.L. Volakis, A. Kiourti, 10 - Embroidered antennas for communication systems, Editor(s): Tilak Dias, Electronic Textiles, Woodhead Publishing, 2015, Pages 201-237, ISBN 9780081002018, doi.org/10.1016/B978-0-08-100201-8.00011-4

[2] J. Zhong, A. Kiourti, T. Sebastian, Y. Bayram and J. L. Volakis, "Conformal Load-Bearing Spiral Antenna on Conductive Textile Threads," in IEEE Antennas and Wireless Propagation Letters, vol. 16, pp. 230-233, 2017, doi: 10.1109/LAWP.2016.2570807

[3] B. Hu, G. Gao, L. He, X. Cong and J. Zhao, "Bending and On-Arm Effects on a Wearable Antenna for 2.45 GHz Body Area Network," in IEEE Antennas and Wireless Propagation Letters, vol. 15, 2016, pp. 378-381, doi: 10.1109/LAWP.2015.2446512

[4] M. Neruda, L. Vojtech, M. Rohlik, J. Hajek, R. Holy and M. Kalika, "Application of shielding textile materials in electric vehicles," 2015 24th Wireless and Optical Communication Conference (WOCC), 2015, pp. 113-117, doi: 10.1109/WOCC.2015.7346188.

[5] Abschirmtextilien aus Bremen weltweit im Einsatz, Oktober 2014, p. 24, https://www.innovationsintelligenz.de/abschirmtextilien-aus-bremen-weltweit-im-einsatz-1126588.html

[6] Thüringer Innovationszentrum Mobilit?t/ ThIMo, Funk-und Informationstechnik 2. Mess-und Analysesysteme, 2021, p. 48, https://www.mobilitaet-thueringen.de/fileadmin/ThIMo/Ausstattung/PDF_ThIMo_Ausstattung_2021.pd