Synthesis of silver nano particles and fabrication of aqueous Ag inks for inkjet printing

The main problem in preparing stable and printable inks containing nanoparticles for inkjet printing is to overcome the strong agglomeration of the particles in dispersion medium. In this study, the silver particles with diameter around 50 nm were produced by a simple wet chemistry method. Stable aqueous printable inks were formulated by using the combination of a triblock copolymer and high intensity focused ultrasound (HIFU). Various factors that affect the ink stability, such as, copolymer content and time of HIFU treatment, were investigated. The ink containing 5 wt% silver has a viscosity of about 2 mPa s and surface tension 30 mN m−1 at 25 °C, which meet inkjet printer requirements. Such inks have been successfully printed on Al2O3 ceramics and low-temperature co-fired ceramics (LTCC) and the printed films show low resistivity.

► This work deals with Ag inkjet printing. Long-term stable Ag inks have been prepared by dispersing Ag nanoparticles in water with the help of F127 and high intensity focused ultrasound.
► The fabrication of Ag nanoparticles uses a new approach that is in water medium, which is environmental friendly, and also Ag ink is prepared using water as dispersion medium.
► Printed Ag patterns show the resistivity as low as bulk Ag material, which shows the potential of using such a method to directly jetting Ag interconnections on the substrates.