Disposable cup lid having a tear-resistant straw through-slit

Abstract

A straw-insertable disposable lid is disclosed including a flexible disk-like body having a top surface for covering an opening of a cup, a plurality of intersecting lines of weakness each extending between two ends with the lines of weakness being located on the body and adapted to permit the insertion of a drinking straw through the top surface of the lid and a plurality of intersecting troughs for accommodating a respective one of the intersecting lines of weakness, with the troughs acting to stop the propagation of the tearing of the lines of weakness in a radially outward direction when a straw is inserted into the lid and for closing the plurality of intersecting lines of weakness in response to a fluid pressure force acting on an underside of the top surface of the lid should a filled cup incorporating such lid be inadvertently tilted over. The aforementioned lid if formed by placing a sheet of thermo-deformable material between a male and female die set, the male die including an edge for forming the plurality of intersecting lines of weakness and the plurality of intersecting troughs in a substantially planar portion of the sheet with each trough accommodating a respective one of the lines of weakness, heating the sheet of thermo-deformable material between the male and female die set and substantially simultaneously forming the plurality of lines of weakness and the plurality of troughs during the formation of the remaining portions of the straw-insertable lids.

Dependencies are inferred from the claim text.