Integral skin foam
Integral skin foams are a type of polyurethane foam used to make many automotive parts, exercise equipment, and furniture. The key feature of these foams is a very tough, abrasive resistant skin surrounding a more flexible core. This skin is created during the foaming process by a combination of mold pressure/temperature and blowing agent. Fluorochemical blowing agents, for example, Forane® FBA 1233zd, can often have the ideal solubility and boiling point for this process, and thus typically create a very thick abrasion-resistant skin surrounding the inner foam core.