what is etching primer

Etching primer is a type of primer used on metal surfaces to improve adhesion of the topcoat. It contains a mild acid that etches into the metal surface, creating a stronger bond between the surface and the primer. Some etch primers contain low levels of phosphoric acid, while others contain acetone, toluene, and LPG. The acid in the etching primer improves adhesion, durability, and color holdout of the topcoat. Etch primers are intended for use as primers on new or relatively sound ferrous and non-ferrous metal surfaces. They are perfect for the priming of all types of metal work that require a quick turnaround. Etch primers only require a very thin coat in order to etch the metal surface and create a tenacious bond. They are compatible with most standard decorative paint systems for metals. It is important to note that etch primers have a restrictive recoat window of 24 hours, and it may be difficult to use them on larger jobs. It is always best to speak to a specialist who will be able to advise on the best primer for the job being carried out.