Stretchable Printed Circuits

Materials and processes for the realization of elastic and stretchable conductive tracks

Elastic and stretchable conductive tracks
© Fraunhofer ISC
Silicone rubber film with stretchable printed conductors

The Center Smart Materials and Adaptive Systems develops materials and processes with which not only flexible but also elastic and stretchable conductive tracks can be realized. Electrically conductive elastomers can be printed in almost any geometry on a stretchable substrate (silicone elastomer or thermoplastic urethane) using modern printing technologies such as flat or roll screen printing. The layer thickness can be adjusted both by material adjustments and by using different screens.

 

This process can be used to produce very thin conductive structures with a print resolution of a few 100 µm. The electrical conductivity can be adjusted between 0.6 S/cm and 6,000 S/cm depending on the filler used (carbon-based fillers, metal particles or silver nanowires). By designing the conductive path as a conductive elastomer composite, high conductivities under strain (up to 100%) can be achieved.

Dielectric elastomer with stretchable conductor
© Fraunhofer ISC
Preparation of a dielectric elastomer with stretchable conductor
Specific conductivity as a function of elongation of a conductive elastomer
© Fraunhofer ISC
Specific conductivity as a function of elongation of a conductive elastomer

Our competences

  • Understanding about the interaction of conductive particles in polymer matrices
  • Electrical connection and characterization of conductive elastomers
  • Know-how on printing conductive materials on different substrates

Our offer

  • Development of conductive elastomers with desired properties
  • Process adaptation for optimal printing of conductive elastomers
  • Development of tailored stretchable conductive tracks
  • Overcoatings for mechanically stable conductive tracks