Reliable Pretreatment of Polyamide (PA) Substrates. Optimal plating on plastics requires carefully matching all pretreatment steps to specific type of PA used.

The process described herein provides a reliable method for the metal plating of polyamides with an adhesively strong and decorative coating. In addition to extending the scope of production possibilities for the aforementioned plastics, the modified pretreatment of polyamides provides additional advantages. The intentional omission of the chromic/sulphuric acid solution used in conventional processes not only produces better coating results, but also brings environmental benefits with regard to concerns about the use of Cr-VI. The production sequence has been based on the traditional process to ensure that all existing processing equipment can be easily converted to this type of PA process. The coordination of the individual chemical steps also means that there is only a very small tendency toward plating of the racks. © 2008 Elsevier Inc.