Review of Patented Electric Field Technology with Application to Non-Impact Printing

Abstract

Office waste papers with non-impact printing are difficult to deink. It contains dye, pigment, binders dispersed in solvent which was not responding to conventional flotation cell treatment very well. To focus on green and sustainability of printing industry, deinking of recycled paper containing these inks by using patented technology in a flotation cell with anode and cathode is described. The deinking of non-impact printed inks vs. traditional printed inks is reviewed. The deinking efficiency of non-impact printed inks can be improved substantially by introducing an electric field to the conventional flotation process. The electric field exerts a force on the charged ink particles and it also generates fine bubbles due to the electrolysis of water. Electric field could improve the efficiency of convention flotation deinking process in detaching ink from fiber surface and network. This is because physiochemical and hydrodynamic forces do not provide enough detachment force in the flotation process. Using a combined electrolytic and flotation cell has the advantage of removing the ink from both surface and network based on charge difference between ink and fiber.