2-coat powder-coating breakthrough
Powder coatings are increasingly important for both decorative and protective functions. And usually, if aesthetics and protection both important, two coats must be applied to the substrate, with either a partial or a full curing following the first coat, then the application of a topcoat, and then a second bake at high temperature to cure the topcoat. The process results in a robust, terrific-looking finish, and there are no VOCs released. But curing each layer separately means fairly high energy consumption. Wouldn’t it be great if one of the baking steps could be eliminated to streamline the process?
That’s the idea behind Interpon® Align™, the new dry-on-dry two-coat, one-bake coating system developed by AkzoNobel. Previously, the main problem with what is called the “dry-on-dry” approach was that it was difficult to achieve good film uniformity and coverage when attempting to apply two distinct powder layers without the intermediate curing cycle. The result was a compromise that did not meet either the aesthetic or the performance requirements.
But researchers at AkzoNobel have now overcome the difficulties by using an approach call “charge aligning” during the application of the individual powder coating layers. The result is excellent uniformity for each layer, and outstanding appearance and film performance over a wide range of substrate thicknesses, even on objects of great geometric complexity.
The new technology can be tailored to meet exact color and performance requirements, resulting in a wide range of end-use products, including thick and heavy mass metal parts that meet the most demanding specifications for protection and appearance. And the coating processor achieves this with considerable savings in energy, operational costs and time.