Lid for closing a cup

摘要

A lid (2) for closing a cup (1) along a peripheral sealing edge (10) and a method for producing such a lid. The lid includes at least one aluminum film and an optionally multi-layered plastic layer which is co-extruded onto the aluminum film and has a closed predetermined tearing line (3). The plastic layer is made of plastic based on polyethylene (PE) or plastic based on polypropylene (PP), and the predetermined tearing line is introduced into the plastic layer preferably by means of a CO2 laser. The predetermined tearing line (3) may be provided directly in the region of the sealing edge (10).

主权项

1. A process for producing a lid for closing a cup along a circumferential sealing rim, where lid material for producing the lid comprises at least one aluminum foil and one or more layers of polymer film coextruded onto the at least one aluminum foil, with at least one layer of the polymer film comprising either polyethylene polymer or polypropylene polymer and configured to form an inner surface of the lid, the process comprising:
conveying the lid material past a laser; wherein the lid material is in a form of a continuous sheet, the lid material is sliding on an appropriate support, and the polymer film is facing the laser; focusing a laser beam from the laser on a point within the polymer film and above the aluminum foil when viewed from a side of incidence of the laser, such that the laser beam is focused to a diameter of from about 150 μm to about 350 μm; and introducing a cohesive line of weakness into the polymer film using the focused laser beam, wherein the introduced cohesive line of weakness is introduced in a portion of the polymer film that will face an interior of the cup, and wherein the cohesive line of weakness does not expose the aluminum foil.