Chromium(VI)-free pre-treatment processes for plating on plastics

Biconex develops chromium(VI)-free and manganese-free pre-treatment processes for polymers, especially for the plating on plastics industry. We offer research and development services, plating for various polymers in our fully automated small scale plating facility and licenses of our environmentally friendly processes. Our preconditioning technology for ABS based polymers uses less bath stations than the state of the art with chromium(VI) and therefore fits in every existent production line. All chemicals can be processed in existing standard wastewater systems. Low temperatures and short processing times reduce energy costs and avoid any deformation of ABS parts during the process.

Our chromium(VI)-free pre-conditioning process for ABS-based polymers is a unique patented technology to prepare the surface of parts for a subsequent metal plating process and ensures high adhesive strengths. Unlike the state of the art process with chromium and sulfuric acid and other alternative technologies using manganese it does not rely on selective etching to provide the required surface structure for the metal bonding but a physical foaming process. The surface of the polymer is temporarily softened and allows for oxidation agents to penetrate into a thickness of about one micron. Oxidation of butadien inside the material results in the production of gas bubbles, which generate an open porous structure at the surface.

The new process has been successfully tested in a 100 Liter small scale production facility for about one year under various conditions. It is ready for upscaling to a large production scale and provides customers with a fully chromium(VI)-free plating on plastics line together with the various commercially available chromium(VI)-free top coats.

Pre-conditioning of polymers with chromium and sulfuric acid.