Inkjet material deposition is a promising approach to print multiple functional components for dielectric elastomer (DE) devices. The automatic fabrication process promotes reliable and repeatable results, and allows scaling to a few millimetres, which is advantageous in areas such as microfluidics and optics. We present here the printing and evaluation of novel ink formulae comprising silicone and a conductive filler. Carbon black, the conductive filler, is a popular electrode material. Although it has a relatively high resistance, it has been shown to produce compliant electrodes of good performance for dielectric elastomer actuators (DEA). Carbon black is added to liquid silicone rubber and solvents in order to obtain a solution that can be inkjet-printed. The silicone provides binding of the carbon particles into a soft matrix as well as bonding to the elastomer membrane on which it is printed. Each ink has unique electromechanical properties, e.g. sheet resistances ranging from a few kΩ/sq to MΩ/sq. We can apply different inks to provide conductive electrodes for DEA or piezoresistive components such as the dielectric elastomer switch (DES) - able to locally control charge over DEA - or simple resistor and electrode tracks. We discuss ink behaviours and printed sample components for networks of DEA and combined driving circuitry, all with soft, flexible materials.
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