Ensuring sealing performance

Planning, modification, production launch – switching to new equipment or materials without intermediate optimisation steps is rare. As a leading global supplier of metal can ends and lids, Easytech Packaging is familiar with food industry requirements. By entering the pet food market, the Italian company dared to take the next step – and faced new process requirements.

At the same time, the company switched its production to a PVC-free coil coating. This new coating formulation, together with the new highspeed processing machines for the lids, presented a number of technical challenges. Working closely with Henkel Adhesive Technologies, the provider of the food-grade, water-based sealant Darex WBC 733 PHV for the can end production, Easytech was able to stabilise its processes and safeguard quality.

Headquartered in Fisciano in Southern Italy, Easytech Packaging specialises in the production of metal cans with easy-open ends (EOE) or sanitary open-top (SOT) lids. The company became part of the Metal Containers segment of Silgan Holdings in 2021 and has since served as the company’s EOE competence centre in Europe. In this role, Easytech makes a substantial contribution to the segment’s strategic development. By entering the pet food market, the company opened a new chapter, which harbours new business opportunities but also new technical challenges.

Together, Henkel and Easytech tested different filling volumes and analysed the viscosity of the sealant under different production conditions.

High speed meets high demands

Easytech’s entry into the pet food packaging segment started with a major order from a leading brand manufacturer. “This contract has enabled us to access this entirely new market,” commented Dr Fabio Bove, general manager of Easytech.

“The requirements in terms of sealing properties, food safety and process stability are similar but, in some respects, even more complex than those of the human food industry. At the same time, production speeds and material combinations are more demanding. In order to satisfy all these requirements, we had to fundamentally modify our processes,” he said.

Easytech invested in four state-of-the-art, highspeed rotary liners that can produce up to 1,200 lids per minute. However, the customer’s specifications also required the use of a PVC-free industrial coating. Initial trials with it showed significant quality issues, not only in the forming and lubrication of the coils but also in the subsequent application of Henkel’s sealant Darex WBC 733 PHV. The new coil coating brought significant obstacles to Henkel’s compound in terms of gasket placement and dewetting during the initial period, partially offset by a change in the coil lubrication. What initially seemed like a purely technical adjustment quickly became one of the project’s biggest challenges.

At the same time, Easytech was entering new territory technically: while it had long experience in producing with steel, Easytech had never processed aluminium can ends before. The material’s different behaviour during forming and coating added another layer of complexity to the project.

Between nozzle and lid

It was much harder than expected to process the water-based sealant Darex WBC 733 PHV on the high-speed units in combination with the new PVCfree coil coating. The crux of the challenge was placing the sealant accurately on the aluminium lids. The rotary liners are equipped with fine nozzles that apply the adhesive in a rotary motion – a technique that requires a high degree of precision. The close proximity of the individual application nozzles meant that even minor changes at one application point also affected the neighbouring positions, which in turn impacted the pressure ratios and distribution quality. This made the precise adjustment particularly challenging and initially led to non-reproducible results.

A further obstacle was that the interaction between the PVC-free coating solution, which Easytech had not worked with before, and the coil lubricant intensified what is known as the dewetting effect. This led to the sealant shrinking in places and developing holes – unacceptable in the sensitive sector of metal packaging for food products. The result was a massive increase in the rejection rate, which had a very negative impact on production efficiency.

“Introducing new equipment, a new substrate and a new raw material for the cans and lids all at once was a major challenge,” said Giuseppe Scarola, operations manager at Easytech.

“That’s where Henkel’s experience really made the difference. Their experts guided us through every test phase – on site and remotely – until we reached full stability in production.”

Service, training and technology unite

Henkel and Easytech worked closely to optimise the equipment and application parameters. Together, they tested different filling volumes, analysed the viscosity of the sealant under different production conditions and aligned the process to the requirements of the pet food business.

One key lever was the redesign of the stirring process. Henkel identified insufficient homogeneity of the Darex WBC 733 PHV sealant under the new conditions as a key factor for the lack of distribution accuracy. On Henkel’s recommendation, Easytech installed a new stirrer, which resulted in a more homogeneous structure and a significant reduction in the dewetting effect.

Other targeted measures were implemented along the process chain. For example, the coil supplier adjusted the relubrication to minimise undesirable interactions with the sealant. At the same time, Easytech optimised internal process steps to further stabilise the application conditions.

In parallel, Henkel also provided training on how to run the product on the rotary liner systems and supported the fine-tuning of the units to ensure consistent quality. Despite the technical complexity, the collaboration between the companies was constructive throughout – a crucial factor in enabling the launch of series production after six months.

“The most valuable part of this story is the relationship we’ve been able to build throughout the project,” said Fabio Lanaro, regional key account manager for metal packaging at Henkel. “We supported Easytech both remotely and on site, analysing every detail together until the process was fully stabilised and the customer’s requirements were met.”

Providing support for autonomy

With Henkel’s support, Easytech was able to conclude the transition to the PVC-free coil coating successfully. The can-end production has been running stably on all four rotary liners for more than 12 months now. Darex WBC 733 PHV is applied reliably and evenly, rejection rates have decreased considerably, and the end customer’s requirements are satisfied in full.

The real success story lies not only in the technical solution, but in the collaborative approach. Henkel supported Easytech in a project that turned out to be much more complex than initially expected and demonstrated its in-depth understanding of the process details, materials and the challenges on site at every stage.

“Looking back, the key to success was not a new product or new equipment but the knowledge of how to make everything work together,” Easytech’s Scarola added.

Stability in collaboration

As a technical partner with an in-depth expertise in products, processes and practical applications, Henkel not only provided support in analysing the problems but also in delivering concrete solutions. This transfer of knowledge shows the importance Henkel attaches to supportive partnerships and sustainable service.

In the end, a technically challenging project evolved into a lasting and trust-based collaboration – demonstrating that with the right partner, even unexpected challenges can be mastered.

The professional exchange between Henkel and Easytech continues, even after the successful ramp-up of production. Through this ongoing partnership, Henkel supports Easytech in ensuring production stability as volumes continue to grow in the dynamic pet food segment.