Investigation of printing and curing micro-conductive ink tracks using syringe-based deposition system and oven on fabric

Abstract

Miniaturization of electronic structure for smart textile application has been seen dominated in recent years due to its low cost and light but it requires flexibility to resist stresses. Printing using conductive inks provides the flexibility but it remains a challenge since current printing techniques suffered from ink incompatibility especially on conformal substrates due to its rigidity and low flexibility. An alternative printing technique via syringe-based deposition system is proposed since it capable of printing various materials with different viscosity level. An investigation is required to evaluate its feasibility in printing micro-conductive ink tracks on fabric. The effect of printing and curing parameters including printing speed, deposition height, curing time and temperature to the morphology of the ink tracks and conductivity were investigated. Electrical tests were performed to determine the resistance level. It was found that 0.50 mm width of designated ink track was successfully printed and printing with higher speed reduced the track width while deposition heights affected the thickness of the ink track. Printing speed of 7.00 mm/s with deposition height of 0.59 mm were concluded as the optimum printing parameters. A longer curing time and higher temperature used resulted in lower resistance as expected. The lowest resistance achieved was 1.70 Ω cured at 160°C for 45 minutes. It was proven that a syringe-based deposition system able to print micro-conductive ink track and oven is suitable to cure the ink properly on fabric.