Foil insert moulding and challenging recyclat

Injection moulding tool for industry project “toolbox”.

15 partners worked together to make it happen: The toolbox with inserted films and inlay made of post-industrial recyclate (PIR), first presented at K 2022, is being used by machine manufacturer Arburg to demonstrate its largest injection moulding machine.

Hofmann – Ihr Impulsgeber developed the injection moulding tool for the large toolbox. The goal: a high-quality design, a valuable feel and high stability for the outer shell and the associated inlay.

Digital filling studies for demanding raw material.

The gray inlay of the toolbox is injection moulded from RECOPOUND® brand PIR, which is obtained from PET bottles. According to the manufacturer, this consumes up to 40% less CO₂ than manufacturing with new material.

Although sustainable, the PIR is demanding in the injection molding process and has special processing requirements. Therefore, among other things, good mold temperature control is immensely important for a perfectly moulded component.

As a time- and cost-efficient solution, Hofmann used digital simulations and filling studies to optimize the mould even before it has been manufactured: Thanks to analyses of the flow behavior of the plastic melt, tempering and cycle time, the technical experts from Lichtenfels perfected the mould shapes for the special plastic material.

For example, the placement of the injection nozzles could be ideally determined in a very short time and with little effort. Furthermore, the intensive mould temperature control allows the shortest cycle times, if using suitable peripherals.

Foil insert moulding in the injection mould tool

For a special design highlight, the toolbox can look forward to eight 3D design foils: As part of the insert molding process, preformed foils are inserted at each corner of the mould, fixed in the mould with vacuum and then back-injected.

With this technique, the substrate material can be more strongly deformed in comparison to traditional in-mould decoration (IMD). This makes it ideally suited for more strongly formed surfaces – just right for the distinctive and hard-wearing toolbox.

Involved project partners