Polyethylene Coating: A Thin layer of polyethylene on both sides gives durability. The outer layer guards the design and printing, although the interior layer acts to be a sealant, generating the carton completely leakproof. The initial patents for food paperboard containers day back to the beginning of the last century. https://oilrecyclablepackaging.blogspot.com/2025/09/eco-friendly-packaging-for-water.html