“Eco-friendly corrosion inhibitors” should not contain heavy metals, non reportable compounds or ingredients, and be green-label compliant and also zinc free.



Currently, the challenges faced by the coatings industry are not just to reduce costs and improve performance but also to fulfill strict legal requirements. The so-called “Eco-Friendly” anticorrosive coatings used to contain high or even 100% solids (like powder coatings), have low or zero VOCs. They do not contain reportable compounds, are green-label compliant (United States feature) and, in Europe, following the Directive 2004/73/CE, are non toxic for the aquatic media.

Therefore, to avoid any danger to the aquatic media, “eco-friendly corrosion inhibitors” should not contain heavy metals, non reportable compounds or ingredients, and be green-label compliant and also zinc free.

As a matter of fact, most of the current eco-friendly corrosion inhibitors are already heavy metal and zinc free. They are also green-label compliant and non toxic for the aquatic media. However, they show poor earlier corrosion protection and poor accelerated corrosion testing performance. Furthermore, in order to show good real world performance they have to be modified to enhance corrosion resistance. Besides, most of them are not always user friendly and the majority are not cost effective.

A New Corrosion Inhibitor

Thanks to the coordinated efforts of the Nubiola Anticorrosion Technical Centers of Barcelona, Spain, and Atlanta, GA, a new eco-friendly corrosion inhibitor has been recently launched into the market. Its name is Nubirox 301.

From a chemical point of view, Nubirox 301 is a metal phosphate complex on a silicate core. As it has no reportable compounds, it is green-label compliant. It also fulfils the aforementioned European Directive. Thus, it is non-toxic for the aquatic media.

With an average particle size of just 1.0 microns, Nubirox 301 is a direct anodic inhibitor and has multi-substrate performance. Due to its unique morphology, overall anticorrosion performance is second to none. It is suitable for water- and solvent-based systems and improves early corrosion resistance. Another key feature is the excellent package stability. Nubirox 301 also offers price stability, as it shows improved cost-effective performance on multi-substrates.

To conclude, let me suggest using our recommendations for the inhibitor selection and formulation. Generally speaking, you should evaluate inhibitors on an equal cost basis, not on equal weight or equal volume basis. And above all, use accurate and realistic test methods.

Some other eco-friendly corrosion inhibitors are already in the pipeline and will be available shortly. Joint projects involving formulators´ technical staff and our Barcelona and/or Atlanta labs colleagues may lead you towards success.

For more information, visit www.nubiola.com.