Previously plastic bottles used for hot-filling at between 182F and 192F needed ribs or panels in the sidewall to absorb the distortion that occurs as the beverage cools to room temperature, said Amcor's,the manufacturer that developed the new type poly ethylene terephthalate (PET) container.
PowerFlex bottles can be run on existing glass filling lines with little or no equipment modification, Amcor stated.
A major trend in the beverage packaging sector is the replacement of glass bottles by PET containers, according to AMI, a research fir. AMI estimates the market for standard beverage closures willgrow by 6.2 per cent annually to 2009. Meanwhile the market for custom beverage closures will grow by about 12 per cent, driven by developments in sports tops and carton mechanisms.
About 158 billion plastic closure units were produced in the Western European market last year, making up about 40 per cent all closures. Of these 66 per cent of the plastic closures were for usedfor beverages.
Amcor said this week Tradewinds Tea became the first company to use Amcor's PowerFlex PET bottle, first announced in March this year.
"PowerFlex is the first-ever, true panel-less, ribless, hot-fill PET bottle. It provides the aesthetics, performance and feel of glass - which is what beverage marketers, such asTradewinds, have long been anticipating," Amcor stated.
Amcor developed its PowerFlex bottle by designing a special base to absorb the vacuum created by cooling liquids. A diaphragm within the base draws upward as the liquid cools. The inverted coneshaped diaphragm deflects upward as the vacuum is created, absorbing any distortion that may affect the sides of the bottle.
Christy Lichtendahl, marketing manager for Tradewinds Beverage Co., said the company had been reluctant to package its 16-ounce ready-to-drink tea in PET containers.
"We've been waiting for a PET bottle to come along that would give us the ability to maintain the same look and feel of our current glass container," she stated.
Tradewinds brews its own tea in specially designed kettles then fills it into the bottles at temperatures between 180F and 185F.
Previously the company used a glass bottle similar to a beer container.
"When considering a PET bottle, we had several design objectives," Lichtendahl stated. "It was important to us to replicate our Tradewinds logo on the bottle neck. Also thebottle needed to have smooth panels so that we could apply our existing pressure-sensitive label."
Lichtendahl said the company was able to run both the pressure-sensitive body label and neck shrink label on existing equipment without modification. To alter the filler, the company changed a setof change parts and added a second capper to accommodate the new polypropylene closure.
Amcor PET Packaging has about 80 sites in 21 countries, including plants in the UK. The parent company, Amcor, is headquartered in Australia.