With the increase of environmental regulations making solvent-based corrosion protection expensive and complicated to apply and dispose of, protective powder coatings such as zinc-rich primers offer premium corrosion protection without harming the environment. Zinc-rich primers are considered sacrificial coatings, a subset of protective powder coatings meant to dramatically slow down the process of corrosion if the top layer is damaged. This makes them the perfect coating for steel in highly corrosive environments. Zinc-rich primers are great for use in marine, tanker, or underground environments, all of which are considered immersive environments.
There are two types of zinc-rich primers: inorganic and organic. Organic zinc-rich primers are primers that use binders such as epoxy, polyurethane, or alkyd, etc. More commonly used for highly corrosive environments on oil rig platforms, chemical plants, and more, organic zinc-rich primers require a top-coat to be long-lasting.
Inorganic zinc-rich primers do not require top-coats in more mild atmospheric environments and provide better galvanic protection overall. Inorganic zinc-rich primers usually use only silicate as a binder and is applied as a powder using the blast method on “white” metal, metals that are light-colored alloys. This is the type of zinc-rich primer Houston Powder Coaters uses.