5. Post-processing

Post-treatment of solid copper or copper cladding can be decorative (coloring, patinas) or technical (protection of the manufactured object).

• Until the last decade, the technical purpose of post-treatment of copper coatings was to provide temporary protection against part degradation, using passivates based on hexavalent chromium or copper corrosion inhibitors (benzotriazole). Today's functional post-treatments concern the industrial sector of printed circuit boards with, for example, the application of organometallic conversion coatings or coatings containing compounds with a cationic group - C = N ⁺ [US 005 85 8074A].

  One such process involves forming a copper(II)-based organometallic conversion on the copper coating of a printed circuit board, then converting said layer...