Concentrating substances

摘要

The present disclosure relates to a method for concentrating a substance, which may be an electrostatic printing ink. An apparatus for concentrating a substance is also described.

主权项

1. A method for concentrating a substance, wherein the method comprises the steps of:
(a) providing the substance, the substance comprising chargeable particles in a liquid carrier; (b) passing the substance between a conveyor and a first electrode, wherein a potential is applied between the conveyor and the first electrode such that the substance becomes adhered to the conveyor, and wherein some liquid carrier may be removed from the substance on the conveyor; (c) passing the substance on the conveyor past a moving surface, wherein the substance contacts the moving surface and a potential is applied between the conveyor and the moving surface, such that the chargeable particles are disposed to move toward the conveyor and some of the liquid carrier is removed to increase the concentration of the chargeable particles in the liquid carrier on the conveyor to form a concentrated substance on the conveyor, the conveyor and the moving surface then diverging from one another; (d) removing at least some of the concentrated substance from the conveyor; and (e) wherein at least some of the liquid carrier removed from the conveyor in step (b) or step (c) is passed between a second electrode and the conveyor without being returned to a source of the substance, and a potential is applied between the conveyor and the second electrode such that the chargeable particles are disposed to move toward the conveyor, and some liquid carrier is removed.