Folding

As edge folding the folding is a decorative material ( plastic film or textile hereinafter) to a carrier part edge by 90 ° or 180 °. The folded material is then attached to the back of the carrier part using a suitable joining process (e.g. gluing or welding ).

history

The folding process in the automotive industry was first used for trim parts in the 1970s. At that time, PVC film was stretched onto a simple, flat support made of molded wood fiber material using mechanical slides and joined using HF welding. Later on, the complicated three-dimensional geometry of many parts required other joining processes. In particular, adhesive bonding should be mentioned here, which was initially carried out with solvent-based and later with solvent-free adhesives. The adhesive pressure was also generated with sliders. These can be used cold or, depending on the application, heated internally, or preheated from the outside using hot air or IR radiation .

Since the mid-1990s, there has been another adhesive-free joining process for folding with ultrasonic welding . Almost only 180 ° bends are now produced, as the back injection molding technique is also available for 90 ° . It is used for trim parts in the footwell area, dashboard, A, B and C pillars, interior door panels, etc.

literature

B. Sattlecker: Folding with ultrasound. In: plastics . 3/1999, p. 48.