Preventing Delamination in Flexible Packaging

As the packaging industry evolves to meet brand and consumer demands for more sustainable solutions, many converters are considering adding flexible packaging manufacturing to their service offerings. After all, flexible packaging typically uses less material and is lighter in weight than most rigid alternatives.

Printing companies that will succeed in the flexible packaging market need to know not only how to print on flexible materials, but also how to convert them. Otherwise, they risk packaging performance failure; a common contributor to flexible packaging performance failure
is delamination.

The Domino Effect of Manufacturing Defects

Delamination during the pack-out process, in particular, can lead to big problems for your customers. If a multilayer film’s layers begin to peel away from each other, the compromised material can cause equipment malfunctions, increased maintenance needs, and production delays.

Worse still, products in defective packaging often can’t be used. The wasted resources undermine sustainability goals and packaging buyers’ bottom lines. No print service provider wants to be known as the source of these headaches, yet solving delamination requires addressing multiple factors simultaneously.

Understanding and Addressing Delamination

The root causes of delamination are varied but often boil down to issues with material compatibility, adhesive selection and application, and process controls.

Let’s start with one of the most common culprits — material incompatibility. Materials that are not chemically compatible do not bond well, which can lead to weak adhesion during the lamination process and eventual delamination. Some materials may also have different mechanical properties between layers of the packaging, such as differences in flexibility or tensile strength, which, in turn, causes stress on the application during handling and use.

Poor mechanical strength of adhesive has resulted in the delamination of this multilayered film. | Credit: Trinseo

Adhesive selection and application are equally critical. A poorly chosen adhesive or an unevenly applied layer can result in inadequate bonding strength. Converters must ensure they select adhesives tailored to the specific materials they’re working with while maintaining precise application techniques to avoid thin or inconsistent layers.

Environmental and mechanical stress also play significant roles. Flexible packaging is often subjected to high humidity, extreme temperatures, or rough handling during transit; these stresses can compromise the bond strength of its layers, leading to separation. Sometimes, these stresses exist inside the finished package itself. For example, flexible packaging with heavy or sharp-edged items can cause so much stress on the packaging material that the film begins to delaminate.

Preventing Delamination

I would be remiss if I didn’t start by stating the right materials partner can help prevent delamination by supporting a converter with services, from developing latex binder formulations to offering support with preventive methods.

I mention latex binders because they also play a crucial role in preventing delamination. Latex binders can enhance adhesion between layers in flexible packaging and reduce the risk of failures due to solvent retention, improper mix ratios, or curing conditions. These flexible and durable bonds can withstand mechanical and environmental stresses, reducing the risk of layer separation.

The design of the polymer can be customized to enhance compatibility with specific substrates — optimizing bond strength through precise monomer compositions. Material partners can also work with packaging converters to modify the cross-link density and other parameters of latex, in turn amplifying the application’s flexibility and adhesive strength.

Latex binder formulation can also help enhance packaging sustainability. Choosing a binder engineered and certified for repulpability enables the packaging application to undergo standard mill recycling. By altering the formulation of your latex binders, packaging converters can continue to prevent delamination while maintaining performance and sustainability requirements.

Beyond binders, manufacturing advancements in other components and processes can further reduce delamination risk. The use of water-based adhesives minimizes the potential for solvent retention, which can weaken bonds between packaging layers. Additionally, converters can introduce surface treatments to their packaging production, such as corona discharge, plasma treatment, or primers. Doing so can modify the surface energy of the substrate to be laminated and support improved adhesive performance.

Delamination During Production

While material selection is crucial to helping prevent delamination, good process control is also necessary to improve your flexible packaging manufacturing. Converters should optimize their lamination conditions by carefully controlling lamination temperature, pressure, and speed, thereby supporting proper adhesion between packaging layers.

The structural integrity of flexible packaging also hinges on the proper design and engineering of the film. Using the correct number of layers and barrier materials within the laminate structure is critical and can impact structural integrity. Converters can also adjust the adhesive coating weight to improve performance depending on the substrate, mechanical properties, and surface.

Additionally, routine quality testing and monitoring can help stop delamination in its tracks. Implementing stringent quality control measures, such as regular peel strength and delamination resistance tests, identifies potential weak points before they escalate into production disasters.

Converters should also monitor the environmental exposures their packaging faces during storage and transportation, as factors such as humidity or temperature fluctuations can cause delamination.

Finally, operator training and process optimization are essential. Skilled operators, armed with a deep understanding of lamination parameters, are the frontline guardians of quality. Their insights — combined with feedback from quality testing — can position a converter for long-term success in the flexible packaging market.

Looking Ahead: Flexible Packaging’s Role in a Sustainable Future

As the CPG industry embraces this next chapter, flexible packaging will continue to shine as a practical, sustainable solution. With the right partnerships and proactive strategies, packaging converters can be trusted partners to brands if they also enlist the help of the right partners to eliminate package performance failures — all while supporting everyone’s sustainability journeys.