The present invention relates to a multilayer system F1 comprising: a layer C1 comprising at least one polypropylene, an adhesive layer Ad made up of a hot-melt self-adhesive composition CA, and a layer C2 comprising at least one polypropylene, said multilayer system F1 comprising at least 80% by weight of polypropylene or a mixture of polypropylenes relative to the total weight of said system. The invention also relates to the use of said system F1 for producing a recycled item.