Up-Graded Plant Promises New Innovations In Food Packaging

New innovations in food packaging and related plastic promotional materials are beginning to appear on the production lines at Hamilton’s Convex Plastics thanks to a recent $2.5 million plant up-grade.

Convex Plastics General Manager, Owen Embling, says the operation since March of their new German-imported Alpine 3-Layer Co-extruder which is retro-fitted with a Hamilton-made Weighbatch Gravimetric Control System, has increased the plant’s production by almost 100% and allowed the production of new types of polyethylene plastic film formerly unavailable for food packaging in New Zealand.

The 10m tall Alpine co-extruder had to be lowered through the factory roof and required a purpose-built tower to house it. Embling says the decision to marry it with a locally-made control system was not only more cost effective but made sense as the Weighbatch system offered all the features they required. "It was also our first gravimetric control system so having access to help from only three minutes away was quite a bonus."

Now at the press of a few buttons on a computerised keyboard which can easily be reprogrammed to accommodate different product specifications, the Weighbatch system monitors the measurement to a fraction of a degree of sometimes as many as 20 different base materials which combine together to create the finished film’s desired qualities, be it strength, clarity, breathability or shine.

As a result Convex Plastics can now offer a variety of specialised form fill and seal films, and they have just released a range of modified atmospheric packaging (MAP) designed to prolong the life of specific fresh fruit and vegetables. Also newly available are aromatic plastic promotional bin wraps and banners able to be scented with the aroma of choice, from bubblegum to fresh bread.

Central to the increased output and extended product range, according to Embling, is the Alpine’s ability to process plastic with a greater range of raw materials such as metallacene resins, and the ability of the Weighbatch Control System to ensure the absolute accuracy and uniformity of the finished products.

"As a result customers can expect the hundred-thousandth pack to look exactly like the first," he says, adding that the ability to guarantee the consistency of the finished film ties in nicely with his company's multiple- award winning flexographic printing which has won them five highly commended Pride In Print accolades in the past three years.

The new technology has also enabled Convex Plastics to market enhanced product properties like increased speed of operation in flow wrap machines, better sealage, and less waste.

"We're now able to use less and less film to do the job through source reduction, a process which uses less raw materials," Embling explains. "This effectively provides customers with a lower cost in most cases, and always provides them with less kilos of packaging to then be got rid of in the waste stream."

"The new system has increased our output, enhanced our ability to guarantee quality, and enabled us to produce packaging which is much kinder to the environment."