Barrier coating
Also: barrier coating, grease barrier, moisture barrier
A thin functional coating that gives paper resistance to grease, moisture, or oxygen. A key enabler of paper-for-plastic replacement.
Barrier coatings make paper competitive with plastic for food and flexible packaging. They can be aqueous dispersions (bio-based acrylics, modified starch, modified latex), extrusion coatings (polyethylene, polylactic acid), or fluorochemicals (now being phased out due to PFAS regulation).
The 2020s shift toward PFAS-free and biodegradable barrier coatings is driving rapid innovation in the specialty paper industry. Recyclability of the coated paper has become a key purchasing criterion.