coatings add to pet Product Performance

French manufacturer Sidel offers its Actis 20 downstream rotary plasma coating machine, which deposits a 1/10-micron amorphous carbon barrier layer inside the bottle. The result is a bottle 30 times more resistant to oxygen permeation, with a seven times enhancement for CO2.

Another European development is the Bestpet PET bottle developed jointly by Coca Cola and the University of Essen in Germany. Bestpet uses a silicon oxide barrier coating applied to the outside of the PET bottle by a vacuum plasma process developed by packaging equipment maker Krones AG (Neutraubling, Germany) and vacuum specialist Leybold Systems. The coating improves barrier properties by a factor of two or better, while keeping the beverage in contact solely with food-grade PET. The Krones coating unit installs inline between the molding machine and filler, and can handle 500 mL bottles at speeds up to 20,000 per hour.

On this side of the Atlantic, PPG Industries (Pittsburgh, PA) has launched a new generation of the firm’s Bairocade barrier coatings in a single-serving juice bottle for York, Pennsylvania-based Graham Packaging L.P. The epoxy-amine coatings are a development of Bairocade coatings in use for the past five years in Australia and the Middle East for beer and carbonated soft drinks. PPG claims shelf-life enhancement of up to three hundred percent for coated bottles. Bairocade is applied by an electrostatic spray process followed by a curing bake in an infrared oven.

With an anticipated annual end user demand of 700 billion PET bottles by 2002, expect the pace of technology change in this segment to accelerate, especially as the brewing industry comes around to plastics.

COATINGS ADD TO PET PRODUCT PERFORMANCE