Buergo.fol, a manufacturer of films for the food industry and technical applications, is increasingly focusing on sustainable packaging systems. Saving resources and recycling while maintaining the product’s quality are the declared goals of the company, headquartered in Siegenburg, Germany. The company offers foamed APET films in thicknesses ranging from 300 to 800µm in various colours. At the 2012 PETnology Europe Conference in Nuremberg Dr Kurt Stark, Director Business Development at Buergo.fol, gave a lecture on “Sustainability in practice with foamed APET”.
Beverage cup made of foamed APET film (photos: Buergo.fol)
All too quickly now, under the guise of “sustainability”, companies are bridging the gap in the use of renewable raw materials in the production of films, the manufacture of biologically degradable films and in the natural cycle by subsequent composting of the films or packaging. Stark believes that this is a very good and well-rounded concept that will surely forge its own path in the future. But in 2013 this concept will not yet be complete because of numerous hidden hazards behind the “green curtain”. For example, the raw material polylactic acid (PLA) is a renewable resource, but it is manufactured today in the USA based on genetically modified corn. It is unthinkable that this PLA could be used in films and packaging in many European countries, especially in Switzerland.
The same criticism applies to the heavily advertised compostability of packaging made using biomaterials, which can even be certified according to DIN EN 13432. Only a few packages and bags land in (industrial) compost – as before, they continue to be fed into incinerators. There is no existing method for recycling biomaterials as yet. In contrast, if large amounts of PLA were to be sent to the recycling plant, the raw materials would then contaminate the waste stream and make other recycled plastics unmarketable. Even a small market share of PLA could lead to a serious disruption of the infrastructure for recycling PET bottles in Europe. The entire system of biopolymers based on renewable materials is still in its infancy. There are only a few suppliers, and they often have a monopoly in the market.
Even in terms of the properties of the materials, films made of biopolymers cannot measure up yet to established products manufactured on a petrochemical basis because in many cases they are still too brittle, sensitive to water, temperature-sensitive (below 60°C for PLA based biopolymers), poor-sealing (for cellulose-based), difficult to process, and do not function as a barrier.
Buergo.fol’s Managing Director Gregor Schleicher does not see the end of the potential for biopolymers any time soon. He is firmly convinced that without the support of petroleum-based polymers, it would be impossible to achieve the properties in films and packaging that customers are accustomed to. Schleicher also expresses reservations from a moral viewpoint regarding the manufacturing of plastics using food intended for humans and livestock.
In summary, concludes Stark, this still does not justify the high price for films made of biomaterials and very few consumers are willing to pay for them because they are not yet convinced of the advantages of packaging made of biomaterials. They are even confused and uncertain about their use due to the continuous flood of new organic logos and the continuing controversial public debates about the issue.
He believes that it may take many years before bioplastics and the products produced using them become a serious alternative to petroleum-based plastics. The company is monitoring these developments very closely, but not until the concept of renewable resources is sensible and consistent in all aspects will consumers be willing to accept them.
The alternative: foamed APET films
In the meantime, Buergo.fol is going along a different path to more sustainable products. For some time now, the company has been offering foamed APET films in thicknesses ranging from 300 to 800µm under the new brand name “Buergo.PET expanded”. These films are produced on the cast extrusion facilities at the company’s site in Ingolstadt, Germany.
The weight of the foamed film is said to be approximately 30% lower in comparison to that of conventional APET films. This means material savings and a sustainable use of natural resources. Buergo.PET expanded has a high mechanical strength and is suited for use as a deep draw film on all common thermoforming and packaging plants, even on older models, says Stark. This means processors of the film and packagers using the film can still use their existing plants without having to retrofit them, and they can even continue working with their standard machine settings.
Black bottom section of a package made of APET film (top) with a magnified view of the foam structure (bottom)
The thermal formability is said to be better in comparison to non-foamed films. For example, deep recesses can be formed without requiring the use of a stamp. The structures applied to the thermoforming mould are formed precisely and with detailed contours on the foamed film. The foamed APET film can be cut perfectly. Sharp edges and sharp corners are avoided now and wear on the cutting knifes can be minimised.
Besides weight saving, the insulating effect is to provide an improved keeping quality of the packaged product. According to Stark, the foam structure is attractive, has soft and smooth haptics, and provides at the same time a good grip. Buergo.PET expanded is available in various colours and the film can be printed, which allows new and individual packaging ideas.
The foam films based on polyester are suited for applications such as trays, tablets, pans, plates, dishes and cups for the food and the non-food area. In the food area, the foam films are approved for the packaging of meat and sausages, cheese, snack items, fish and seafood, poultry, baked goods and ready-made meals, and for consumer and industrial goods such as hygiene products, household goods, office supplies and electronics. The company guarantees the combination of stackability and slippage resistance in the packaging.
Foamed APET films are available in various colours. (photos: Buergo.fol)
Composite films
The new foamed APET films can also be bonded to a laminate with barrier films from the company in a further refinement. The bond is strong and permanent. Delamination does not occur in cover films or in bottom films. By selecting suitable laminating films, it is possible to vary the barrier properties for oxygen, carbon dioxide and water vapour as well the opening characteristics of the packaging. The spectrum ranges from permanently sealed packaging to packaging that is especially easy to open (easy to peel).
Savings potential
Sustainable development will be part of the future of the packaging market. In times of fierce pricing pressure, the economical use of resources will become more important than ever. The following table shows the potential savings in packaging by comparing the foamed APET film Buergo.PET expanded with the non-foamed Buergo.PET film.
| Typical bottom film | Not foamed | Foamed APET-Film |
|---|---|---|
| Buergo.PET | Buergo.PET expanded | |
| Material | APET/PE | APET/PE |
| Thickness in µm | 300/50 | 300/50 |
| Weight in g/m2 | 466.2 | 350.0 |
| Weight 100,000 m2 in kg | 46,620 | 35,000 |
| Weight savings in kg | – | 11,620 |
| Weight savings % | – | 24.92 % |
Weight savings in kg and % of Buergo.fol’s expanded APET film with non-foamed film (source: Buergo.fol)
The table shows how much packaging material weight can be saved when using the foamed film. The foamed APET sheet is mainly produced with recycled materials which results in a very low value for the carbon footprint (kg of CO2 eq./kg polymer) in a life cycle assessment (LCA) and a considerable saving of energy.
With barrier films also suitable as package for meat and sausages
Summary and outlook
The sustainable concept from Buergo.fol has already been realised in the production and sales of foamed APET films in the Buergo.PET expanded product class. In comparison with other plastics, Schleicher claims that in comparison to polypropylene (PP), the foamed APET film is characterised by better processing properties, higher plant effectiveness and lower energy consumption. Compared to polystyrene (PS), Buergo.PET expanded is said to have better mechanical properties with comparable recyclability. The company intends to pursue this and other sustainable concepts vigorously in the future.
www.buergofol.de
