Phosphate-free, low-temperature zirconium-based pretreatment in powder coating
New phosphate-free pretreatment chemistries are available to today’s finishers to replace iron phosphate in washer systems. This article answers the most common questions asked about these new chemistries with emphasis on a leading zirconium-based system. Because of the low temperatures at which these chemistries work, end users not only protect the environment, but also save considerable costs in energy use.
As a finishing expert, you realize more than anybody that your pretreatment system is unique, and the nuances associated with making it produce consistent parts daily are many. Variability in washer design including line speed, nozzle alignment, vestibule length, and the parts processed including configuration, soils, and metallurgy are just a few of the variables that make your process unique.
The challenge you face is optimizing the efficiency of your finishing system in a world of increasing energy, chemical, labor, and waste treatment costs. This is all in an environment of increasing environmental regulations and consistently doing less with more. Specialty chemical companies have addressed these needs by developing alternative pretreatment processes to conventional iron and zinc phosphate. Among the most widely used technologies are organosilanes and the salts and acids of the transition metals titanium, zirconium, and vanadium. These new technologies are enticing because of the significant potential for energy reduction and the elimination of phosphates. This article answers the most common questions about one of the leading processes, which uses zirconium.