Industry-First Recyclable Mono-Material Retort Packaging Unveiled by BOBST, Brückner and Mitsui Chemicals

Three global packaging leaders have collaborated to tackle one of the toughest challenges in flexible packaging: creating a recyclable structure capable of withstanding high-temperature sterilisation. At the K 2025 trade fair in Düsseldorf, the companies revealed their joint innovation, a mono-material metallised retort pouch made entirely from polypropylene.

Retort packaging is widely used for sterilised foods, ready meals, and pet food that undergo heat and pressure treatment to ensure safety and long shelf life. Traditionally, these pouches are made from multi-layer laminates that combine materials such as polyester, aluminium foil, and polypropylene. Although these composites provide excellent protection, they are difficult to recycle due to the mixture of materials.

The new mono-material solution replaces this complex structure with a single polypropylene base film, making the packaging compatible with existing recycling streams while maintaining high-barrier performance.

How the Innovation Works

The packaging combines three key technological contributions:

• Mitsui Chemicals developed a heat-resistant primer that improves layer adhesion and maintains film stability during retort processing.

• Brückner Maschinenbau applied inline coating and orientation technology to create ultra-thin, dimensionally stable films that resist shrinkage and deformation at high temperatures.

• BOBST provided its vacuum metallisation system using AluBond technology, applying an ultra-thin metallic layer that achieves high oxygen and moisture barrier properties while remaining recyclable.

During testing, reels of film were produced at Brückner’s pilot lines in Germany and metallised at BOBST’s Manchester facility in the United Kingdom. The films maintained strong adhesion and barrier performance both before and after retort testing, confirming their potential to replace traditional multilayer laminates.

Overcoming Technical Barriers

Historically, metallised films have been unsuitable for retort packaging due to corrosion, delamination, and loss of barrier performance under extreme heat and pressure. This development overcame those limitations through precise integration of the primer, coating, and metallisation steps.

Engineers from the three companies report that while the early-stage trials were successful, further testing and optimisation are required before the solution is ready for full-scale production. The next phase will involve industrial trials to validate performance under real-world conditions and confirm compatibility with sealing, filling, and lamination processes.

Implications for the Food and Packaging Industries

For food producers, converters, and brand owners, this breakthrough could reshape how high-barrier packaging is designed. By using a single polymer type, the solution simplifies recycling and reduces waste-management complexity.

Benefits include:

• Compatibility with existing polyolefin recycling streams.

• Lower carbon footprint through reduced material and energy use.

• Simplified packaging design without sacrificing product protection.

• Easier compliance with the upcoming European Packaging and Packaging Waste Regulation (PPWR), which requires higher recyclability and lower environmental impact.

For brand owners in sectors such as pet food and ready meals, the innovation supports sustainability targets while maintaining shelf life and packaging integrity.

Advancing Circular Economy Goals

From a sustainability standpoint, mono-material packaging represents a major step toward a circular economy. Traditional composite films often end up in landfill or incineration, while mono-material polypropylene can be collected, sorted, and mechanically recycled at scale.

By reducing material complexity, the new structure lowers resource consumption, simplifies reprocessing, and minimizes contamination in recycling streams. It also supports manufacturers in achieving their net-zero goals by reducing embedded carbon and improving resource efficiency.

The development aligns with the broader industry trend of combining functionality with circularity. As more companies seek low-carbon packaging alternatives, technologies that merge recyclability with high-performance protection will become essential to achieving climate targets.

Next Steps and Outlook

The three companies are now working to scale up the process and prepare for commercial rollout. This includes testing the film with converters and brand owners, optimising machine settings, and validating performance across multiple product categories.

If successful, the innovation could transform the high-barrier flexible packaging segment by enabling recyclable pouches for sterilised foods, one of the few remaining categories where circular solutions have been difficult to achieve.

Industry analysts note that this milestone shows how collaboration between material science, machinery, and coating technology can unlock new sustainable packaging possibilities. As the packaging sector accelerates its shift toward circular and low-carbon systems, developments like this will play a central role in bridging the gap between technical performance and environmental responsibility.

Source: packagingeurope.com