This work demonstrates the single-step, in situ chemical polymerization
process for the direct synthesis of aqueous, conducting
polyaniline based ink and its spectroscopic characterization. The
developed ink was then successfully utilized for printing an IDT
pattern using an inkjet printer on a flexible, untreated polymeric
substrate and used as a sensor for humidity. The advantage of using
inkjet print technology is the high speed and low cost of fabrication
as well as the possibility of printing onto flexible substrates. This
conducting polyaniline based aqueous ink will also have potential
applications in low cost RFID tags, polymer photovoltaic cells
and in printed, low cost flexible electronics devices like thin film
transistors (TFTs) and organic light emitting diodes (OLEDs).