Some experiments in powder charging and its significance to industrial processes

The electrostatic charge acquired by powders is frequently blamed for industrial problems in the production and use of powders. Both excessive cohesion and the opposite effect of poor packing have been blamed on electrostatic charging. Charged powders are produced intentionally and used in a number of industrial processes including electrostatic powder coating and reprographic systems. Even in these systems where much research has been carried out the mechanism of charge formation and decay, and the effects of the powder charge are not fully understood. In this paper a number of experiments concerning powder charging and its results are reported.