Pharmaceutical blister packaging equipment makes cuts in the film in the form of both perforations for
tearing and punching to arrive at the final shape of the card. A well-suited material must cut cleanly
without angel hair and, in many cases, must actually have a degree of brittleness. The brittleness helps
the film to break in a functional way so that the user can remove doses and gain access to the product.
A film with too much brittleness combined with blades, edges, or anvils well beyond their original wellfunctioning
state can often create the undesirable “herringbone” patterns in the film that leads to
stress propagation and part failures. Films chosen with too much ductility often just hinge in cases like
this making it impossible for a package to perform its function.