Effect of Ink Viscosity on Print Density in Gravure Package Printing

Pages:216-219
Pankaj Kumar and Rinkee (Department of Printing Technology, GJUS&T, Hisar,)

In this case study I analyse that a small difference in ink viscosity can produce major variations in print quality. Variation in ink viscosity affects the print quality i.e. print density decreases when low viscosity of ink and the print density increases with increase in ink viscosity but after a saturation point it starts to decrease, clogging problem comes here so dot percentage decreases i.e. density decreases. So we can say that ink viscosity and density are closely related to each other.Also the variation in ink viscosity effects on dot sharpness and dot size etc. If the ink have low viscosity then dot gain problem is created, dot sharpness decreases, mottling defect also comes. In case of high viscosity, dot sharpness increases and high viscosity sometimes causes the ink to dry inside the cell, resulting in cell clogging. This reduces the efficiency of cells to carry ink and transfer to substrates. Keeping viscosity unchanged helps to maintain print quality to great extent. Controlling the ink viscosity is very important from both quality and economical point of view.