‘Consumers today want products that are not just functional, but environmentally friendly,’ comments managing director Dominique Schlenk. ‘Our cold-glue application heads enable manufacturers to meet these expectations without sacrificing efficiency or precision.’
Robatech’s cold-glue technology streamlines the production of paper carrier bags, ensuring reliable adhesion while minimising material waste. At the heart of the process are two core application heads: Presto and Sempre. These versatile tools offer a range of coating widths, enabling seamless production of both flat handles and paper carrier bags.
According to Dominique, the efficiency of Robatech’s system lies in its high switching frequencies and impeccable adhesive guidance. He says the result is a precise cut-off and flawless edge definition, which not only save kraft paper but also ensures that the paper edges inside the bag don’t protrude – a common issue in less refined manufacturing methods. ‘With our technology, manufacturers can apply glue in all required widths and beads, whether it’s for handles or the bags themselves, without any excess adhesive seeping out or requiring additional margins,’ Dominique explains.
The cold glue process
Robatech’s cold-glue application involves several key stages that ensure precision at every step of the process. First, an adhesive coating is applied to an endless strip of paper, which is folded and cut to form the flat handles. In the next phase, jetting heads apply cold glue beads to the kraft paper, securing the flat handles in place.
Dominique points out how cold glue’s irreversible bonding is essential for ensuring strength and durability. ‘The adhesive penetrates the paper fibres and forms a robust, long-lasting bond, which is critical for carrying heavy loads,’ he says.
Following this, cold glue is applied intermittently to a continuous web of paper, where the handles are placed and adhered. A longitudinal adhesive bead or coating is then applied to the continuous paper web, which is folded into a tube, cut and finished with a series of cold-glue beads that secure the bottom flap.
Presto and Sempre
One of Robatech’s standout features is the flexibility of its Presto and Sempre heads. The Presto head offers varying application widths, from narrow strips for handle production to wide coatings for securing the kraft paper to the bag. ‘With Presto, manufacturers don’t have to worry about excess glue spreading beyond the edge of the kraft paper, which saves material and boosts production quality,’ Dominique explains.
He says the Sempre electric jetting head takes reliability a step further by providing precise bead application for both the handles and the bottom of the bag. This level of precision ensures stability and strength, especially in high-load scenarios. The Sempre head even features an integrated material pressure regulator, allowing for fine-tuned adhesive application, while an optional sensor monitors every aspect of the bead’s placement and volume, reducing the risk of defects.
‘Efficiency, quality and sustainability are not mutually exclusive,’ Dominique concludes. ‘With our cold-glue technology, manufacturers can produce high-quality paper carrier bags that meet the growing demand for eco-friendly packaging solutions, while also optimising their own production processes.’
