At K 2004, Groupe Sidel said it has extended a partnership with additive producer Milliken Chemical intended to develop technology for making injection stretch blow molded bottles in polypropylene.
The two companies have been working together for about a year to get PP bottles that are as clear as PET. Milliken makes clarifying agents, while Sidel is working on elements such as stretching and preform design.
Sidel of Le Havre, France, which sees opportunities in juices, isotonics, dairy products and water, as well as dehydrated and sterilized products and pharmaceuticals, recently sold its first PP line to Packpet in Brazil. Packpet will provide the bottles to Tampico for drinks with high juice content and no preservatives. Sidel said it has another five projects in negotiation. On its SBO Series 2+ machines, outputs can now reach 1,500 bottles per mold per hour.
Another French machinery supplier, Saint-Ouen l'AumÃ´ne-based ADS, also is pushing the technology. It has been collaborating with Total Petrochemicals for the past two years. At the show, it made small water bottles with no clarifying agent, which were close in appearance to PET versions. The G62 two-cavity linear reheat machine can make 3,200 bottles per hour.
Sales director Pascal Lefevre sees prospects mainly in hot-fill applications: ``PP can take 141° Celsius [286° F]. Hot-fill temperature for fresh juices is 92° C [198° F].''
Juices are oxygen-sensitive, and PP has relatively high oxygen permeability, but Lefevre said the bottles should be good for a three-week shelf life.
Aoki Technical Laboratory Inc. said the U.S. market for PP injection stretch blow molded bottles is growing quite fast.
Aoki's Japan sales representative Eiji Nishizawa said that while high gas permeability is an issue for food and drink, it is less so for pharmaceutical packaging, where PP's chemical resistance and suitability for steam sterilization prove a winning combination.
Hiroshi Chino, vice president of Aoki's Elk Grove Village, Ill., unit, said the original market was baby bottles, but more recently there has been growth in neutraceuticals - or food supplements.
``In 2003, we sold a lot more machines for PP than in any other year,'' Chino said. ``The trend will continue.''
Not all machine suppliers are convinced. Krones AG has done tests with PP bottle production, but Wolfgang Reichert said there is little pull from the market. He said that though the lower-priced PP is attractive, its high gas permeability makes it unusable for oxygen-sensitive products.