Easy opening through diverging spiral tearing.
Packaging films are torn open in a diverging exponential fracture if starting from a specific but relatively simple starting notch. A very large opening is then created (see video below)
Here there is no special preparation on the film (or added guiding structure) : the spiral is really a natural path which is triggered by a specific initial condition. General propagation rules are described in this article.
joint patent CNRS/USACH/UCHILE.
Contact : benoit.roman[at]espci.fr