Reverse technology bring mono-material benefits: Dow and Menshen launch sustainable spouted pouches

29 May 2019 --- Dow and Menshen, manufacturers of caps, closures and single-serve capsules, has launched spouted pouches made of mono-material films. The innovation was made possible as the company developed a new Reverse Spout Sealing Technology, which enables mono-material production by applying heat during the spout sealing process. The technology allows converters to address the recycling criteria for flexible packaging and can help brands meet increasingly stringent sustainability packaging goals.

The incoming regulatory changes that directly impact the packaging industry are abundant, and the industry needs to innovate – fast. By 2025, EU regulations state that 55 percent of all packaging must be recycled. Also, although it will differ by member state, as a rule of thumb, plastic products must contain 25 percent recycled content by 2025 and 30 percent by 2030. These regulations fall within the Single Use Plastics Directive (SUPD), which was approved in the European Parliament in March. It places pressure on the entire plastics value chain, and invites innovation, especially in the mono-material space. 

“We basically reversed the idea of where and when the heat needs to be applied during the spout sealing process,” explained Dr. Peter Sandkuehler, global application technology leader at Dow’s Packaging & Specialty Plastics business. “By transferring the heat from the pre-melted spout base directly to the sealant layer of the film, we’ve solved two challenges at the same time: how to easily seal spouts to mono-material films, and how to prevent the hard spout ribs from cutting into the film.”

The new process is designed to easily seal spouts in more heat sensitive, mono-material structures made from all polypropylene or all polyethylene packaging layers. Rather than traditionally applying the heat from outside the pouch forming film to melt the seal layer and the spout, the latter is pre-melted at its base before insertion into the pouch and sealing.

The introduction of the reverse spout sealing technology is the result of a three-year joint development between Dow and Menshen, who are working with a number of partners on technology integration and assist brand owners and converters to put the new sealing approach into practice. Both companies are working with leading manufacturers of pouch-packaging machines worldwide to commercialize the technology.

“The beauty of the process is its simplicity,” says Sarah De La Mare, Business Development officer at Menshen. “It is actually more logical to apply the heat from the inside rather than from the outside, whether you use mono-materials or not. We are currently working with several machine manufacturers to ensure that this technology can be integrated into new and existing spouted pouch making lines.”

Reversing the traditional sealing process helps reduce the excess heat needed to be applied from the outside of the film to seal the inner, lower density film layers to a high-density spout base. At the same time, the packaging structure is less dependent on a film’s thermal resistance and film cut-in is avoided, resulting in good quality spout sealing and a pouch that looks great on the shelf.

“At Dow, we have been working on expanding our portfolio of polyethylene-based mono-material solutions for several years. When looking at spouted pouch applications, we knew that changing this would not be an easy task and would require out-of-the-box thinking,” says Jaroslaw Jelinek, marketing manager for EMEA, Dow Packaging & Specialty Plastics. “What Dow and Menshen bring to the market today is a transformative technology that contributes to the plastic circularity goals that Dow and the entire industry have committed to.”

The reverse spout sealing technology was successfully tested at Dow’s Pack Studios in Horgen, Switzerland.Menshen spouts sealed in mono or laminate film structures contain Dow solutions such as DOWLEX 2750ST, ELITE 5960G in outer layers coated with OPULUX HGT and AFFINITY sealants.

The technology is suitable for most pouch sizes and for a wide range of applications – from baby food, condiments, and detergents, to personal care applications such as shampoos, shower gels, or body lotions. For packaging applications that cannot compromise on content preservation, Dow combines this technology with barrier solutions in structures that are designed for recyclability.

Innovation on the pouch front
In addressing the demand for sustainability in flexible packaging, several pouch innovations have sprung up recently.

Global plastic packaging supplier Amcor took a big sustainability stride with the launch of the AmLite Ultra Recyclable high-barrier laminate pack in April. It the first product made from the company’s landmark recyclable polyolefin film, which Amcor announced last year. The new high-barrier laminate can package a range of food, home, personal care and pharmaceutical products. It can be recycled in existing polyolefin recycling streams. 

Mondi also has developed a fully recyclable stand-up pouch made of a monomaterial (polyethylene) with a removable wrap-around label. The landmark design overcomes many shortcomings in the recycling process and is the result of a joint four-year effort by Mondi, Werner & Mertz, EPEA Switzerland (Cradle to Cradle), Der Grüne Punkt – Duales System Deutschland and Institut cyclos-HTP to transition flexible packaging to a circular model. The design is based on Mondi and Werner & Mertz’s initial patented innovation: a 100 percent recyclable polyethylene pouch with detachable decorative panels. The pouch replaces conventional flexible packaging for Frosch products.

 Edited by Laxmi Haigh