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Chemical Technology • May 2016
between 10 and 400 µm thick, the thickness fluctuating less
than 5 % over the entire width. The exceptionally uniform,
homogeneous films are made of addition-curing silicone
rubber compounds without the use of solvents. They are
manufactured under cleanroom conditions to eliminate
any impurities.
Coating the upper and lower surfaces of the silicone films
with a flexible, electrically conductive material produces
deformable capacitors. When a DC voltage is applied, the
electrodes are attracted to each other electrostatically and
compress the soft film material. The layer of elastomer
material becomes thinner, and spreads out in the plane.
The capacitor becomes flatter and wider overall. When the
capacitor is discharged, the elasticity of the film causes it
to return to its original shape. The entire process is silent
and can be repeated as often as desired.
Subtle nuances of such capacitance changes can be
measured and thus used for sensory purposes, for example
to display body movements. In actuators, they can control
small movements, for example. This enables the design of
very precise and efficient pumps, electric relays, artificial
muscles, gripping devices and sound systems. If several
hundred capacitors consisting of silicone film are placed on
top of each other – referred to as stacks by experts – it is,
with the aid of motion, even possible to generate electric-
ity. In a project publicly funded by the German government,
Bosch and WACKER have already successfully developed a
generator that can use the upward and downward motion
of ocean waves to generate electricity.
The Danish company, LEAP Technology, and WACKER
have been developing electronic components that can
be incorporated discreetly into textiles and have already
developed the first prototypes. LEAP Technology makes
these out of Elastosil
®
Film.
The pilot coater, which can coat solventless and emulsion coatings for most substrates, coats products under real conditions.
Coated with conductible
electrode layers, the
silicone film constitutes
a deformable capacitor
(dEAP), if energised.
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