an electrodeposition method wherein a conductive substrate such as , for example , a metal fastener is first coated by means of an anodic electrodeposition process , then subjected to thermal curing , and then subjected to a cathodic electrodeposition process . the anodic electrodeposition process is carried out until the coating insulates the substrate at which point the coating process stops . the curing step lowers the dielectric strength of the anodically deposited coating , thereby allowing the substrate to accept a cathodically deposited top coat . the resultant coated substrate demonstrates superior corrosion resistance properties and improved cosmetic appeal .