Gardobond® CU – Eco-friendly and energy-efficient application of barrier coatings

With the innovative Gardobond® CU 7600 and Gardobond® 7602 technologies developed by Chemetall top-quality copper layers are applied to materials such as iron, steel, zinc or diecast zinc in an electroless and environmentally friendly way. The process applied at ambient temperature generates an excellent substrate and thus enables further processing by galvanic coating for decorative and functional purposes. The new Gardobond® CU products replace the traditional and well-established technologies involving the electrodeposition of copper or nickel.

In the chemical and galvanic deposition of metals a barrier coating ensures that there is no direct contact between the material and the galvanic electrolyte. The most common methods used for the application of a barrier layer as the first step in galvanic coating are copper-plating or nickel-plating. These technologies are reliable, manageable and have therefore established themselves worldwide. However, they are environmentally harmful and very demanding in terms of energetic input.

With the innovation Gardobond CU 7600 and Gardobond CU 7602, Chemetall now offers an environmentally friendly alternative. The new technologies allow for a simple application of barrier layers made from copper on substrate materials like iron, zinc and their alloys. At the same time, these products meet evermore stringent market demands: simple and safe process, efficient and cost-optimized technology, conservation of resources as well as high quality.

For the development of these new processes particular emphasis was placed on environmental compatibility and uncomplicated effluent treatment. The processes do not contain any strong complexing agents such as cyanide, EDTA or HEDTA and, except for copper, also no heavy metals. Moreover, they are free from organic or inorganic stabilizing agents and do not require reducing agents such as formaldehyde, hydrazine or hypophosphite.

The new technologies operate at ambient temperature and do not need external power input. As the process operates on the basis of chemical reactions, it is also suited for providing hollow parts or components with recesses or bores with an even and largely constant barrier coating. 2/2

The use of Gardobond CU 7600 and Gardobond CU 7602 does not alter the process sequence in existing plating plants. As both processes are relatively insensitive to the carry-over of extraneous ions, DI water can generally be omitted in the upstream cleaning processes. Depending on the application, also the additional cleaning step for electrolytic degreasing upstream of coating is obsolete.

While Gardobond CU 7602 generates permanently glossy copper layers, Gardobond CU 7600 produces matte surfaces. Both technologies are successfully applied in the most diverse industrial sectors such as the automotive industry, production of welding rods, fittings, jewelry, and electrical and household appliances. The new processes are in addition also used in the production of connecting elements for windows, doors or furniture.