Sub-project: Investigations on the use of conductive webs for textile adhesive bonding for the contacting of smart textiles and adaptation of conductivity by means of appropriate finishing
BMWi ZIM-ZF 4250108AG7
The research project developed conductive thermoplastic adhesive nonwovens based on different manufacturing processes and adapted to the requirements. This was done by: 1) introducing conductive particles during the manufacturing process of the adhesive fleece to realise low conductive surfaces; 2) additional highly conductive finishing of the already conductive adhesive nonwovens. The conductivity of the fleece can be specifically adjusted to cover different areas of application. With the developed conductive adhesive nonwoven, it is possible for the first time to carry out the contacting in the laminating process necessary for the production and not, as was previously the case, in an additional work step. Robust and reliable contacting is the result.
The large-area electrical contacting of textile surfaces for the production of smart textiles is still a challenge despite many years of research work in this field. In particular, the guarantee for reliability and long-term stability of such conductive connections has not yet been solved. The approach pursued in the project of using adhesive nonwovens with a conductive finish to realise large-area electrical contacts in smart textiles starts at this point and significantly increases the reliability and long-term stability of such connections. Corresponding materials were not yet available and have been developed and tested in the project. Ensuring reliable electrical contacting in smart textiles allows the realisation of diverse tasks in the fields of heating, lighting, energy generation, automotive and medical technology.
Taking the requirement profile into account, the project partners determined two applications and defined the respective specifications. From this, concepts for the development of the required end properties were worked out. The research work was carried out under the realisation of the following development focal points:
- Production of conductive adhesive non-woven materials from already conductive thermoplastics and using conductive additives.
- Investigation and testing of the application of the manufactured conductive adhesive nonwovens.
- For the adjustability of a desired conductivity - additional highly conductive finishing of adhesive nonwovens made of already conductive thermoplastics.
The conductivity of the adhesive nonwovens can be specifically adjusted in this way so that the following technical functionalities can be realised:
- Conductive and thermoplastic adhesive nonwovens for contacting (high conductivity)
- Antibacterial and/or antistatic surfaces (low conductivity).
Results and Applications
The conductive adhesive nonwovens developed can be freely cut to size and can be used both for contacting textile heaters and for antibacterial surfaces, e.g. medical plasters. The possible applications of the conductive adhesive fleece are mainly in the target markets of smart textiles, automotive textiles and medical textiles. Engineering development services are offered by the TITV Greiz in order to overcome the previously existing entry barriers for textile-based contacting. With the new product of a highly conductive adhesive nonwoven, it is possible for the first time to
- homogeneously feed electricity into large-area, highly flexible textile heating modules (such as seat heaters in vehicles, heated clothing, mobile plant heaters, electric blankets
- for horses and other animals),
- to reliably contact flexible and textile components in smart textiles, whereby the contacting is done in the laminating or lamination process necessary for production and not in an additional work step,
- to make the contacting and connection of solar cells, e.g. from solar films, to solar modules much more efficient,
- simplify the contacting and assembly of light-emitting textiles, such as large-area electroluminescent light-emitting textiles.
Fig. 1: Low conductive weave produced by extrusion process Fig. 2: Continuous highly conductive equipment
AB-Tec GmbH & Co. KG