Electrostatic powder coating of plastic substrates with epoxy powder

摘要

Process for coating objects of various shaped made of insulating plastic and situated on holders on a moving conveyor that is connected electrically to earth, comprises (a) degreasing and rinsing the surface of the object to be coated; (b) rinsing the object with an aq. soln. contg. a surface active agent; (c) forming a coating of an epoxy resin powder on the object by electrostatic spraying from a nozzle; and (d) subjecting the deposited epoxy resin layer to a thermal shock treatment by heating the coated object to at least 150 deg C in less than 2 mins., and maintaining this temp. for at least 5 mins.