A special non-stick coating for the inside of the packaging has been developed through a joint project by three research centres in Germany, the Fraunhofer Institutes for Process Engineering and Packaging IVV said.
The coating would allow processors to add the extra convenience to their packaging for sticky products such as ketchup and mayonnaise.
The coating reduces the amount of shaking or tapping consumers must apply to containers to get the last drops out, said Cornelia Stramm, head of Fraunhofer's functional films business unit.
In some cases, up to 20 per cent of product is left in the packaging when it is dumped in the trash can, she stated.
The wastage not only reduces the actual amount of product consumers get, it also poses a problem for recycling centres. The leftovers first have to be removed from the packaging, which is expensive, time-consuming, and uses a great deal of water.
If the products are pharmaceuticals, chemicals or pesticides, the rinsed-out leftovers also have to be disposed of in a suitable manner.
"We are developing packaging materials that reduce left-over traces to half or less," Stramm stated.
The researchers are experimenting with thin films of up to 20 nanometers thick. The films are applied to the inside surface of the packaging, said Michaela Müller, a scientist with the Interfacial Engineering and Biotechnology IGB in Stuttgart.
The coatings are made from a plasma similar to the type used in neon lamps. They are made by placing the plastics into a vacuum. Gases are injected into the vacuum chamber and ignited by applying a voltage.
The scientists found that they could deposit different coatings with defined properties on the surface of the packaging, depending on the proportions of electrons, ions, neutrons and photons in this luminous gas mixture.
The scientists plan to present the first samples of the new packaging to the public for the first time at K2007, the international trade fair for plastics and rubber, to be held in Düsseldorf from 24 to 31 October.
The research scientists at the IGB are now working to improve the adhesive strength of the coatings and other properties.
"The coatings must not change the properties of the materials," Müller stated. "They must remain capable of being industrially processed to form bottles, tubes, or stand-up pouches of the kind typically used for liquid soap."
Meanwhile the Fraunhofer research team are examining how the coatings stand up to mechanical stress, temperature fluctuations, acids and alkalis.
The coatings could be commercially available in about two to three years, putting an end to tapping and shaking, estimates Stramm.
Fraunhofer, IGB, the Munich University of Technology and a number of unnamed commercial partners are involved in the research.
