Substrates, especially those having plated metal surfaces, and subjected to passivation treatments in baths that incorporate one or more film-forming agents at least one of which does not require chromium and includes anions or cations of elements other than chromium. Typically, the anions or cations are introduced as bath-soluble salts which react with the plated surface of the substrate to form an adherent, coherent passivation surface film. Also present within these baths are a source of hydrogen ions and a bath-soluble carboxylic acid or derivative activator for enhancing the rate of the passivation reaction. Articles passivated in baths incorporating these film-forming agents have a hydrophobic surface that exhibits corrosion resistance and that typically has a bright finish.
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