Compostable film targeted at dried food products

A new high barrier compostable film based on renewable materials has high transparency and gloss and is suitable for dried food products, claims Innovia Films.

The manufacturer said its new flexible film, NatureFlex NK, has similar properties to that of co-extruded Oriented Polypropylene (OPP) film, is heat sealable on both sides and has a print receptive surface.

“Testing has confirmed that the moisture barrier of NK is similar to that of conventional plastics such as polypropylene (PP) and polyethylene terephthalate (PET),” said Andy Sweetman, Innovia Films global marketing manager for sustainable technologies.

He explained that until now compostable packaging materials have typically been used with fresh and chilled food products where their permeability proved an advantage: “This excluded them technically from significant areas of the industry requiring excellent barrier,” said Sweetman.

Food applications

He said that Innovia’s new coating technology means that NK can now be used to package dried foods and snacks such as biscuits, cereals, crisps and snack bars.

Sweetman said that with the enhanced moisture barrier on offer, Innovia expects the NK film to offer similar shelf life to that of PP and PET films: “As this can vary greatly depending upon pack type and product we are currently undergoing extensive shelf life testing at customers' facilities involving various product areas,” explained Sweetman.

He would not be drawn on the components which enhance transparency and gloss, citing confidentially, but said the coating technology was responsible for improving those particular properties.

Equipment

In terms of integrating the new film into an existing food packaging line, he told FoodProductionDaily.com that equipment modification is unlikely but slight adjustment to existing settings may be necessary.

Sweetman said that NatureFlex film is naturally antistatic for trouble free machinability and high machine performance:

“We are currently undergoing extensive testing at various converters and machine manufacturers in order to ascertain potential packaging speeds for various applications,” he added.

Formats

Sweetman said that the new film is available in 20, 23, 30 and 45 micron thicknesses and can be used for a variety of pack formats – VFFS, flow wrap, twistwrap and overwrap.

In addition, the NK can be used for lamination to other biofilms, he claims.

“We have successfully tested NK on solvent, solventless and water based lamination systems.”

Standards

The NK meets EN13432 and ASTM D6400 composting standards, and in terms of home compostability, Sweetman said that the required testing has been completed, with certification now pending.

He said the NK films are comparable to the NV range of Innovia films that are used to package confectionery, pasta, pulses and rice, as both are based on similar technologies: “However, we have utilized our technical know-how in order to significantly reinforce the barrier properties of NK."

In common with all bio-materials, NatureFlex is more expensive than basic conventional plastic polymers, said Sweetman, but the company envisages that NK, with its unique barrier properties, will be used in more technical applications where the cost differentials will be less marked.