摘要 |
The present invention is directed to improved methods for increasing the effective contact area of electrodes during the electrocoating process. One preferred embodiment of such methods comprises the first step of coating a non-conductive workpiece with a conductive primer. Next, the areas surrounding the respective contact areas for the electrocoat electrodes are coated with a contact area coating composition having greater electroconductivity then that of the conductive primer. Next, the coating electrodes are fixed on the contact areas for electrocoating. The workpiece is then submerged into an electrocoating bath, and finally sufficient electrical change is applied to the prepared workpiece to electrocoat the workpiece. Compositions having such greater electroconductivity and which are suitable for use in the improved methods of the present invention comprise a substantially uniform dispersion of approximately 5% to 10% by weight of a polymeric binder, approximately 40% to 50% by weight of a metallic powder, approximately 38.5% to 54.5% by weight of a compatible solvent, and approximately 0.5 percent to 1.5 percent by weight of modifying agents.
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