Saran polymers, polyvinylidene chloride (PVDC)/vinyl chloride copolymers, have long been known for excellent barrier characteristics against both water vapor and oxygen permeation.

This paper covers the development of a new high-barrier PVDC copolymer film (HBPVDC) for lamination use. The film is about ten times more resistant to oxygen transmission and about five times better a barrier to moisture passage than regular Saran film.

Laminations including HBPVDC films as the barrier ply offer a transparent alternative to foil and metallized structures. In addition, HBPVDC laminations have excellent flex performance characteristics while maintaining barrier properties.

Structures can be designed for cooking foods in a microwave oven or in retort pouches. Food packages in HBPVDC laminates may also be used in conjunction with metal detectors for tramp metal detection.

Applications of high-barrier laminates include snack food, drug, and pharmaceutical packaging; retort pouches for food and medical packaging; and bag-in-box packaging for liquids and industrial uses.