The group is composed of a planar, three-membered ring comprising two carbon atoms and one oxygen atom.
Epoxy resins containing Bisphenol-A or BPA are used as the inside coating of almost all food and beverage cans. The function of epoxy resins are to provide a protective lining on the interior surface of food and beverage cans to prevent the cans’ contents from contacting and reacting with the metal walls, ensuring sterility.
Many types of internal enamel coatings are available for food containers including epoxy-phenolic, epoxy-amino, epoxy-acrylate, epoxy-anhydrite, vinyl organosol, thermoset polyester, thermoset polymer coated, phenolic, and oleoresinous.
The original can coatings were based on oleoresinous products that include all those materials made by fusing material gums and rosins and blending them with drying oils such as linseed or tung (Chinese wood oil).
Epoxy-phenolic are the commonly used lacquer. They are epoxy resins based on epichlorohydrin and bisphenol.
They are combined with phenolic resins, which re produced by the reaction of phenol with formaldehyde.
This combination gives a gold lacquer with good flexibility, adhesion and chemical resistance.
Epoxy in food packaging
