The barrier properties of a mono-PE bag for dry pet food demonstrate Siegwerk’s functional coatings in the development of recyclable packaging solutions made for circularity. These barrier coatings enable the switch from multi to mono-material pet food packaging with same packaging and process performance.

The company jointly produced a new high-barrier mono-material packaging, which not only offers the same packaging and process performance as the multi-material structure commonly used for dry pet food but is also fully recyclable.

With its new regulations and directives, the EU is increasing the pressure on brand owners and packaging manufacturers to rethink the design of packaging towards circularity. “New approaches are needed to meet the upcoming regulatory requirements for circular packaging,” said Belal Habib, head of brand owner collaboration at Siegwerk.

He said, “The challenge is to find a recyclable design that also meets the respective performance requirements of the packaging.” For example, pet food packaging does not only have to be food safe, but also requires barrier properties, such as resistance to oils and fats, to keep the food fresh and maintain the packaging's structural integrity. For this purpose, multi-material structures with a metallised layer have commonly been used so far. “The problem: they are not recyclable,” added Habib.

He believed that this is where barrier coatings applied in thin layers and inline with regular printing inks can help to switch from multi-material structure to recyclable mono-material solution for a circular economy.

Siegwerk’s Cirkit GreaseBar is an inline printable grease barrier coating, and Cirkit HeatGuard, a coating for high-end sealing processes that can also be applied inline with regular flexo or gravure machines. The recyclable mono-PE bag achieves the same packaging performance as non-recyclable multi-material systems but with the advantage of being fully recyclable.

Both Cirkit coatings are solvent-based, deinkable after delamination and can be printed inline without any loss in print performance. Besides, full PU inks were used that are not only suitable for mechanical recycling but also offer a process performance comparable to NC/PU flexo inks in terms of printing speed and quality. All used inks and coatings comply with the latest recycling guidelines including the German Minimum Standard and RecyClass for recyclable packaging.

“This development success underlines the importance of collaborating along the packaging value chain, combining the specialised know-how of industry experts,” summarised Habib. “By joining forces, we are in a position to make recyclable mono-plastic packaging a reality.”

The samples of pet food pouch will be displayed at Drupa which will be held from 28 May to 7 June, at Interzoo. Visitors to Interzoo can also attend a presentation on “recyclable packaging solutions for pet food” which will be held by Siegwerk and B&B experts on 8 May at 4 PM.