Protective barrier coating for selective paint stripping processes

The present invention relates generally to coatings and coatings removal and more specifically to a barrier coating applicable to aircraft and other structures where repetitive stripping and repainting is anticipated. Aircraft are generally painted with a primer, which can for example be based on an epoxy or urethane resin, and a topcoat, which is based on polyurethane. The subject coating system must resist water and certain organic solvents such as aviation fuel and hydraulic fluids based on phosphate esters such as tricresyl phosphate or tri-n-butyl phosphate. In addition, various coatings removal processes such as chemical, pressurized water and dry media blasting are utilized to remove the coating to the bare substrate. This involves a large amount of manpower, materials, and waste disposal and causes degradation to the substrate. The full coating removal and re-application process also represents a hazard to the environment and personnel. The concept of a barrier coating is applicable to any structure that requires repetitive paint removal. In principle, the coating is applied between a corrosion protective primer and protective topcoat for the purpose of encapsulating the corrosion resistant properties of the primer/surface treatment and allowing for a selective removal of the topcoat using acceptable mechanical coatings removal techniques. The 5-part coating system can be used on any type of structure that requires routine maintenance or repainting to preserve the integrity and/or appearance of the structure. Benefits associated with the concept of barrier coating include a significant reduction in the costs and manpower required to remove and reapply primer and topcoat systems from air- and land-based transportation vehicles, storage buildings, bridges and miscellaneous other structural applications. A second important benefit includes a reduction and/or elimination of the environmental hazards associated with (1) the treatment and disposal of primer and surface treatment residues (chromates, etc.), and (2) the release of toxic airborne pollutants during the precleaning, paint stripping, and painting operations conducted on large structures, thus limiting the exposure of workers.