Kortec Inc. is expanding its multilayer packaging expertise beyond blow molding by developing coinjection molding for food packaging that could replace metal, foil or thermoformed containers.
The company does not have a commercial application yet, but is in development on multilayer polypropylene that can be used for small containers for such items as tuna, single-serve fruits or pet foods. The thin-wall technology includes an ethylene vinyl alcohol barrier and potentially could save up to 20 percent on resin usage compared with thermoforming, while also allowing greater design flexibility, sales and marketing Vice President Russell Bennett said in an interview at NPE2009.
“At the moment, we don't know how far we can take the thinness, but we can do more with this,” Bennett said at the show, held June 22-26 in Chicago.
Like the company's earlier developments with multilayer polypropylene for blow molded containers, the coinjection packages could be hot filled or heat treated, but they will not require a secondary process. That will simplify production for food processors and open other potential business areas for injection molders.
The containers would offer lighter weight than glass or metal packaging, plus good control over the wall thickness and shape, allowing companies to differentiate their products on store shelves compared with thermoformed packaging. In addition, the injection molding process has less wasted material than a thermoformed, multilayer sheet, he said.
Kortec is working both with food companies and processors to develop the coinjection process, Bennett said.
The coinjection containers would continue to build on plastics' ability to replace glass and metal in packaging, but now in a new format for Kortec. The company, based in Ipswich, Mass., also has been stepping up its production of multilayer PP bottles with Gamma-Clear technology developed with Broomfield, Colo.-based Ball Corp. Ball markets the heat-treatable containers in North America with Kortec selling them outside North America.
Since its introduction in 2007, the technology has won over new business, replacing both metal and glass for containers for fruit, soup and sauces, producing bottles that are lighter to ship and also less prone to breakage.
“This [material replacement] has been a main area of interest right now,” Bennett said.
Copyright 2009 Crain Communications Inc. All Rights Reserved.