Composite band for lids for thermoplastic containers

Claim 1

Composite band with lids for thermoplastic containers having a flat and preferably horizontal upper edge or rim, said composite band being of the type comprising downward from the top: a first thin band in aluminum or equivalent material, a thermo-adhesive film bonded to the lower face of the first band, and a second band in thermoplastic material adhering to the first band via said thermo-adhesive film and adapted to be separated therefrom by peeling off, said second band having, in each part corresponding to the position of each lid to be subsequently cut out, at least one slit of curved configuration defining a passage and the ends of which are either located closely together or coincide, wherein the slit is defined on both sides by faces which are very close together and perpendicular to the lower face of the second band, the first band is bonded to the second band via two thermo-adhesive films with different adhesive powers, the film with high adhesive power being provided inside the area defined by the slit, and the film with low adhesive power being provided outside that area, and a thermoplastic tightening or sealing film adheres strongly to the entire lower face of the second band, inside as well as outside the area defined by said slit.