Adipic acid, also called hexanedioic acid, is a dicarboxylic acid. It is used as a feedstock for nylon 6,6 resins and fibres and for polyester polyols in polyurethanes. It is also used in the manufacture of plasticisers, coating resins, lubricants and adhesives, and in leather tanning. Recorded grades are polymer, food, pharma and technical. Packaging formats include 25 kg bags, 1000 kg big bags and bulk. Food use as E 355 is subject to the applicable food-additive specification and permitted-use conditions.