Filling of recycable stand-up pouches

For everything from baby food via household cleaners to chemicals and pharmaceuticals, flexible packaging is heralded as an eco-friendly alternative to cans, cartons or boxes. Sealed pouches made from film consume less material and, due to their lower weight, save fuel during transport, which leads to a lower carbon footprint compared to rigid packaging made from glass or metal.

But flexible packaging such as stand-up pouches (also called doypacks) has a downside: it is typically made from films that consist of several layers of different types of plastics and often also include aluminium foil, which makes recycling more difficult and contributes to the amount of nonrecyclable plastic waste.

This aspect has been recognized by the industry, and with many large companies striving to increase their use of fully recyclable packaging, flexible packaging made from mono-materials is attracting increasing interest in the packaging industry. However, mono-materials are more difficult to form and seal, requiring an advanced forming, filling and sealing process to ensure packaging quality and performance.

For this reason, Spanish packaging machines specialist Bossar Packaging S.A. has been investing heavily in developing, together with Scholle IPN, recyclable solutions for pouches combining mono-material film structures with recyclable components.

One key factor in making recycling-friendly pouches is stringent control of sealing temperature, time and pressure to achieve an excellent seal quality, and this required Bossar’s materials and machine specialists to employ their collective expertise. 

The result is a novel machine design that consists of a pouch maker and pouch filler. The i-Bossar Pouch Maker (i-BPM) machine seals and cools the pouch in a single step, which reduces the stress on the film. This is especially important for mono-materials such as polyethylene films that are sensitive to stretching: as the pouch maker operates continuously, the films are not stretched during pouch production. 

The pouches are then transferred to the new Bossar Clean Filler (BCF) linear pouch filler. By separating the pouch making from the filling and sealing, Bossar can ensure an excellent sealing quality while providing a high level of flexibility to produce multiple pouch formats with minimal changeover time.

In the development of this new machine design, Bossar drew upon an existing machine design that was able to provide the flexibility and performance required for the new process. The new design is based on the company’s line of fully servo-controlled horizontal form/fill/seal (HFFS) machines.

The company’s BMS line features a Bossar-patented transmission system for motion control. This eliminates mechanical parts in the motion system, resulting in a low-maintenance, energy-efficient machine that is capable of quick format changeovers with reduced film waste.

The BMS machines were developed using an integrated automation and drive solution featuring Siemens systems and products. By partnering with Siemens, Bossar was able to design a complete solution for the machine that addresses all aspects of motion control, machine safety, and communication.

Standardizing on one integrated architecture helped Bossar streamline the design, reducing engineering expenses and allowing the company to focus on the mechanical and technological challenges in the machine design.

Having an established technology base helped Bossar develop the new machine design more quickly because the team was familiar with the technology. Bossar was also able to engineer motion control, safety, and general automation using an integrated set of tools, further reducing the time to market for the new machine. 

The company also aims to reduce its products’ carbon footprint wherever possible, and this includes the energy consumption of the machines. Consequently, Bossar uses Simatic ET 200SP AI Energy Meters to monitor energy consumption and uses the line infeed features of the Sinamics drives to recover energy from the drive system in order to reduce the energy consumption of the machines.

Bossar’s commitment to delivering packaging solutions that are as eco-friendly as possible also extends to focusing on reducing material usage and weight in components such as spouts, caps, connectors, and plugs, and on reducing packaging material consumption to offer the most efficient product-to-pack ratio.

Together with the new solution for recyclable polyolefin-based plastic packaging, these features will help manufacturers all over the world make their packaging more eco-friendly while protecting and preserving their products.

Primary Publication in Packaging Europe (Volume 15.2-2020, pages 6ff):

"Evolving Monomaterials through Digitalization" by Joffrey Schubert

May 2020