Abstract: A container lid that is adapted to be placed on a container includes an upstanding side wall and a top wall. The top wall is provided with an opening or through hole for allowing the contents within the container to be mixed while the lid remains on the container. The top wall of the container lid is configured to strengthen and increase the rigidity of the portion of the top wall surrounding the opening. The container lid can also be provided with characteristics allowing the portion of the lid surrounding the opening to flex when a force is applied to the periphery of the opening.

Abstract: A lid for use on a cup having a radially outwardly projecting non-helical brim extending around a mouth thereof. The lid is formed of plastic and comprises a center portion, and a flexible skirt extending downwardly from an outer periphery of the center portion. The skirt includes a radially inwardly projecting annular restriction ring adapted to be positioned beneath the cup brim. The skirt includes a plurality of threads spaced apart circumferentially around the skirt. Each thread extends generally helically upwardly from a location disposed between the restriction ring and a bottom edge of the skirt. The threads intersect the restriction ring to form circumferentially spaced caesurae in the restriction ring.

Abstract: A beverage cup lid is disclosed that comprises a circular closure panel, circumscribed by a side wall that terminates in a resilient, restricted diameter edge for capturing a brim of a beverage cup, and a frustro-conical skirt connected around the restricted diameter edge for increasing the hoop strength of the edge, and an extended diameter flange circumscribing the free edge of the skirt for further increasing the hoop strength of the restricted diameter edge such that the edge retains the brim with a force of at least 1 pound. The invention is particularly applicable to beverage cup lids formed by a plastic web machine that applies heat to only those areas that are deformed into structural components on the lid (such as the side wall, restricted diameter edge, and skirt), and which consequently results in some amount of wall thinning in the skirt, and hence some reduction in the hoop strength that the skirt gives to the restricted diameter edge that retains the cup brim.

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.