Sustainable packaging materials provider UPM Specialty Papers has collaborated with Unipaco, a Polish flexible packaging materials converter, to create a recyclable, heat-sealable salad and herb pot wrapper.  

This new packaging solution is designed to ensure product safety while meeting the stringent German monomaterial requirements, where single-component materials must constitute 95% of the packaging mass. 

The partnership has led to two packaging versions that integrate UPM's papers with Unipaco's coatings.  

The first version utilises UPM Solide Lucent, a barrier base paper weighing 78g/m², coated with a 4g/m² layer of polyethylene (PE).  

UPM Solide Lucent provides a surface for additional converting and printing processes such as rotogravure while the thin PE layer offers the necessary moisture resistance and heat sealability. 

UPM Specialty Papers product portfolio management senior manager Kirsi Lahtela said: “By combining our papers with an extremely thin PE coating, we set out to create a packaging that helped our customers both to meet their recyclability goals and also comply with all relevant regulations. 

“The project provided Unipaco with their first opportunity to test our barrier base papers in addition to more familiar coated one-side papers. We were delighted to see that UPM Solide Lucent performed perfectly on the coating equipment.” 

The second version features UPM FlexPack, an 80g/m² paper, also paired with a 4g/m² PE coating.  

UPM FlexPack is known for its compatibility with various lamination processes and its ability to deliver high-quality print results, particularly with flexographic printing.  

The thin PE coating again ensures the packaging is heat-sealable and maintains the appropriate level of moisture resistance. 

Unipaco CEO and board chair Aleksander Borysow said: “By combining this coating with UPM’s papers, we achieved astonishing results that can be easily transferred to a full-scale production. 

“This solution is available on many other papers and for a numerous end-uses such as meat and cheese wrapping, flexible packaging and even sack production.” 

The new fibre-based salad and herb pot wrapper is claimed to be compatible for food contact and aligns with recyclability standards. 

It will be showcased during FACHPACK in Nuremberg, Germany, from 24-26 September 2024 and at PACK EXPO in Chicago, US, from 3-6 November 2024.