Polyethylene Coating: A Skinny layer of polyethylene on both sides provides toughness. The outer layer shields the design and printing, whilst the internal layer functions as a sealant, creating the carton fully leakproof. The 1st patents for foods paperboard containers date back again to the start of the last century. https://mineralwaterincarton.food.blog/2025/09/24/white-labeling-of-water-bottles-branding-meets-sustainability/