Investigation of some phenomena occurring during continuous ink-jet printing of ceramics

A ceramic ink was prepared, characterised, and subjected to continuous ink-jet printing. The optimum modulation frequency for printing was estimated. The surface free energies of several substrates were determined and different patterns of the ink droplets were printed on these. Phenomena occurring during the process were investigated. The drop-by-drop resolution and ink spreading were found to be dependent on the dispersive/total surface free energy ratio of the substrates. Ink drying was accompanied by powder migration in the droplets deposited on substrates with a surface free energy lower than the surface tension of the ink. Printing of multiple layers was accompanied by the appearance of ridges, splattering, and non-vertical walls. The causes of these phenomena are discussed in this paper.