Tool for perforating a polymeric film with inclined multi-sided projection with straight side walls

摘要

A tool for perforating a polymeric film is disclosed. The tool comprises a support substrate and at least one projection (3) extending from the substrate. The projection is multi-sided with side walls that have straight sides that are tapered upwardly and inwardly from the support substrate at an angle theta (a) that is at least 5°. The angle is measured in relation to imaginary lines extending perpendicularly to the substrate at the locations at which the side walls contact the substrate.