Oxygen-scavenging PET gets the all clear
with an oxygen-scavenging barrier can now be used for packaging
ketchup after gaining regulatory approval in the US this month.
Philadelphia-based Constar International claims to have developed a material that when blended with monolayer PET, binds oxygen, preventing the degradation of products.
The demand for PET is one of the fastest growing sectors of the beverage bottling market, taking over from glass and cans as the container of choice for fizzy drinks and water.
However conventional PET, and plastic in general, is not very good at keeping oxygen from permeating the container and reducing the shelf life of such products as juices, teas and flavoured water. Oxygen has been shown to have degrading effect on flavor, color and vitamin content for many beverages.
The Constar product, called DiamondClear, uses oxygen "scavengers" to minimize the permeation of oxygen through the container by chemically binding the molecules, which has the effect of clarifying see-through packaging.
Permission for food contact by the Food and Drug Administration (FDA) is an important step for Constar which has been developing DiamondClear for the past few years.
Donald Deubel, vice president of corporate technologies at Constar said the development would offer brand-owners "glass-like" appearance in PET.
"This patented development is another important step forward in establishing ourselves asindustry leaders in oxygen scavenging technologies,"
Constar has overcome the haziness that was common in earlier versions of PET oxygen scavenging systems to provide a clear material to display packaging contents.
As the DiamondClear material is blended at the preform injection stage, the technology works equally well with one-step and two-step injection stretch blow molding operations, eliminating the need for high cost co-injection equipment necessary for multi-layer barrier systems.
Unlike systems to apply internal or external barrier coatings, DiamondClear preforms can be produced centrally, then shipped to any blowing location.
Initial FDA approval relates to packaging ketchups only, the company hopes to extend DiamondClear's use for other food packaging in due course.
The company is among the top five PET manufacturers in the US. It also has joint-venture production plants in Holland, the UK, Turkey and Italy.
