Environmentally Compliant Green Solution for Paint Removal

Stripping of a coating is a routine requirement for most painted substrate surfaces of metals, composites and even wood. Removals of a coating from surfaces are usually a prelude to corrosion, tear and wear inspection, and subsequent repair of the components/parts used on military hardware and weapon systems. All land, air and sea going vessels require such periodic maintenance and repair every 3 – 7 years. For helicopter blades, coating stripping and replacement is much more frequent and depends on the frequency of forward deployment. Often they have to be stripped every six months during conflict.

Various paint stripping methods are in use today and can be grouped into: (a) air or water borne media blasting; (b) chemical or solvent based usually methylene chloride; (c) laser/optical or thermal based; and (d) mechanical scrubbing (hand sanding etc.). A combination of the above methods is also used, based on their needs and available facilities. Currently, all these processes are under severe scrutiny by the EPA owing to the generation of large quantities of hazardous waste, air and water borne pollutants and subsequent disposal problems. However, PhotoStrip^®, the topic of this talk is quite unique and different. It is a environment-friendly and uses photochemical process for stripping paint. This process works in conjunction with UV/IR light and water based (green chemistry) strip medium that facilitates the de-bonding of paint from the underlying substrate. Depending on the substrate material and the type of paint used, the stripped paint is generally obtained as a solid compact mass that simplifies the waste disposal. Further, the liquid effluent from the process is largely water, thus posing no disposal problems, and the gas evolved is mostly oxygen.