A Mohr
Elastic conductive tape with non-elastic zones for PCB connection

25.04.2019 Anyone who wants to combine elastic textile conductor strips with electronic components to form smart textiles knows the problems of mass production: 1) most of the fabrication is handmade and therefore expensive; 2) the elastic textile conductor strips have a high failure rate because of tensile stress at the contact points.

© Picture: A Mohr
A Mohr Technische Textilien GmbH, Wuppertal/Germany, and the DITF, Denkendorf/Germany, have developed a solution in the AiF ZIM project Fast-E-Textiles.
The elastic conductor strips are made with inelastic zones at certain points specified by the customer. The conductors are integrated in the interior of the strip. In the inelastic zones, they are exposed to the strip surface and are guided in straight, parallel lines. This creates the prerequisite for an automated roll-to-roll application for the desired electronic components.  A color code indicates the location of the inelastic zones. Using the color codes, a laser strips of the conductor’s insulating coating after which an automated soldering process solders on standardized printed circuit boards (PCB). Because this connection is made in the inelastic zone of the tape, no tensile stress appears on the soldering points, meaning a long-lasting connection in usage is secured.
The application-specific electronic component such as an RGB LED, a distance sensor, RFID sensor, gesture sensor, temperature sensor or similar are clipped onto this base PCB.
If required, the electronic component is subsequently encapsulated so that it is protected from environmental influences.
Thereby, the consumer receives a smart textile that can be offered ready to use and at a reasonable price due to its serial mass production and can thus open up additional markets for smart textiles.