Textile electrochemistry—from the conducting yarn via sensoric and interactive structures to robust and flexible textile micro systems and technical applications

The number of application fields of micro systems and microelectronic components is increasing continuously. International fairs clearly show smaller and compact circuits on foil substrates. Especially, the sensoric and actuatoric sensor systems become more flexible. However, nonrigid and extremely loadable and bendable systems may only be manufactured from textiles. The galvanic and electrochemical finishing of textiles is one way to build textile-based micro systems. A concept for the production of electrically highly conductive, functionalized, and interactive yarns is proposed. The first step of the concept, the highly conducting yarns, are already transferred into an industrialized production and are commercially available. Silver-coated polyamide yarns are already on the market since the end of the 1970s. Till now, the applications have been limited on the use of their anti-electrostatic and antimicrobic properties. The drawbacks of the yarns can be overcome by an electrochemical treatment to increase the metal layer and to create multilayer systems or functional top layers by anodization and other electrochemical techniques like the electro-polymerization and electro-deposition of paint. The treated yarns can be processed by any textile technology. Especially, the metal oxide layers of valve metals and the redox polymer layers are highly interesting due to their semiconducting properties. The surface treatment can be understood as a novel kind of textile finishing. In this way, high conductivity, nano-functionalized surfaces by electro-grafting and special redox-properties for an interactive release of drugs are available. First applications (electroluminescenting fabrics, woven electronic circuits, microelectronic devices as for example textile antennas, capacitors, solar cells and even interactive textiles for the controlled release of drugs) will be demonstrated in this contribution.