Packaging sheet material for packaging pourable food products

摘要

A sheet material (2) for packaging food products and having a number of fold lines (4) formed by compression creasing, so that the fold lines (4) have a recessed profile on the face (23) of the material (2) eventually facing outwards of the package (17) and bearing a printed decoration (5), and a nonconvex profile on the opposite face (25); the decoration (5) has a printed area (36) at least partly enclosing one or more fold lines (37), so as to define, with them and by contrast, an optically detectable register mark (18).