Tube film: alternatives to aluminium barrier laminates

A mix of materials is always a challenge for recycling. This applies not least to triplex films made from an aluminium-plastic composite. They are typically used for packaging ranging from toothpaste and cosmetic products to pet food and building materials. The aluminium layer provides very good barrier and processing properties.

However, when combined with plastic layers, which ensure the puncture resistance, rigidity and sealability of the tube, for example, the material is difficult to recycle. The different materials must first be separated from each other - at great expense. Recycling aluminium is also very energy-intensive. However, manufacturers have alternatives to aluminium barrier laminates, ABL for short, if they want to improve the recyclability of their packaging and save energy.

Levers for better recyclability

A functioning circular economy for plastic packaging is a huge project. Good recyclable packaging is an important part of this. Find out more about the challenges of recycling here and read how Reifenhäuser solutions support manufacturers in increasing the recyclability of their packaging.

Alternatives to aluminium barrier laminates

Some manufacturers have already switched to polymer barrier laminates, or PBL for short. These usually consist of laminated films of one material class, for example polyolefins such as polyethylene (PE) or polypropylene (PP), as well as a polymer barrier, for example EVOH. This composite material is easy to recycle mechanically and also fulfils the functional requirements of packaging.

However, polymer barrier laminates have a decisive disadvantage: as with all laminates, the production costs are very high. Manufacturers have to produce two to three films - with corresponding energy expenditure - and then laminate them before further processing can begin.

Resource-saving solution for tube film with barrier effect

Reifenhäuser has therefore developed a coextruded tube film that is produced in a single production step, does not contain any aluminium and is fully recyclable. The solution fulfils all the requirements for the necessary packaging properties, such as a barrier effect and the required stability of the tube. The film can also be processed on the same tube machines as ABL and PBL tube films.

Layer structure from top to bottom: PE high gloss / print / seal, 2 x HDPE + WMB, Tie PE, EVOH, Tie PE, 2 x HDPE + WMB, PE semi mat/seal

Reifenhäuser as a development partner

‘In the past, packaging design mainly focussed on aspects such as appearance, price or the shelf life of products, but now recyclability is becoming increasingly important,’ says Christoph Lettowsky, who advises customers on recycling issues at Reifenhäuser Blown Film. ‘We are the partner for our customers when they want to improve the recyclability of their packaging.’

And Tino Laue, who holds a similar position at Reifenhäuser Cast Sheet Coating, adds: ‘We work with our customers to find solutions to their challenges that are economically viable for them - but without over-engineering. We look specifically at what properties the particular packaging actually has to fulfil.’

We develop your products together

Would you like to develop new recipes and processes without having to utilise your own production capacities? Our state-of-the-art research and development centre has up to ten high-tech systems, test laboratories and our ‘Extrusioneers’ with their expertise and innovative ideas at your disposal.

Find out more about Reifenhäuser as a development partner

Advantages of coextruded tube film with barrier effect

The Reifenhäuser coextrusion solution for tube film with barrier effect aims to minimise energy consumption and use raw materials efficiently on the way to the end product. Compared to ABL and PBL tube films, coextruded tube film offers manufacturers undeniable advantages:

Fully recyclable as mono-material film

The tube film consists of up to nine co-extruded layers of polyolefins and a polymer-based barrier layer. Together, the layers fulfil all the necessary packaging properties. At the same time, the proportion of foreign substances required, for example for the barrier properties, is reduced and is less than five per cent in the final product. Unlike aluminium barrier laminates, the film is therefore considered recyclable according to current guidelines.

Lower CO2 footprint and lower energy costs thanks to fewer production steps

Production using the coextrusion process requires fewer process steps on the way to the finished tube film than lamination. After all, only one film is produced instead of several. This reduces the energy requirement per kilogramme of film produced - and therefore not only reduces costs, but also the CO2 footprint.

Save raw materials

The coextrusion process uses less material during production compared to the production of multiple laminating films, as losses due to trimming are minimised. The adhesive required for lamination and the intermediate layers of LDPE required for extrusion lamination are also eliminated.

Flexible solution for different systems

Manufacturers can produce both coextruded tube film and film for polymer barrier laminates using various technologies from the Reifenhäuser Group. ‘The Reifenhäuser Group offers its customers both blown film and flat film lines. We can therefore advise customers across all technologies,’ says Lettowsky.

The line technologies complement each other: for technical reasons, blown film and flat film lines have limits in terms of product thickness, but these overlap. Together, both technologies can cover thicknesses of 200 to 350 µm. ‘The thickness of the film is determined by the product that is made from the tube film,’ explains Laue. For example, thinner films are sufficient for travel toothpaste tubes compared to tubes for building materials such as silicone. The experts at the Reifenhäuser Group determine the optimum line technology for manufacturers based on the desired end products and required film thicknesses.