These materials can consist of two or more layers, depending on the level of protection required. The particular application involved also determines the closing systems that are available. One therefore differentiates between simple wrapping products, self-adhesive composite foils, and sealable barrier materials.
The simple wrapping papers include waxed paper and paper that is simply coated or laminated with plastic on one side. If necessary, these paper types can also be supplied with fabric reinforcement or in crêped form. The far thinner and smoother wax-, paraffin- and plastic-coated forms of paper are used for the direct wrapping of small to medium-sized export goods.
Composite aluminium barriers are used as barrier materials for desiccant methods applied for longer conservation periods and in all climatic zones. One main feature is their low permeability to water vapour, regardless of the external climate.
Self-adhesive composite foils are employed as export packaging with long storage periods in arctic and tropical areas in which extreme temperatures and moisture conditions prevail.