Polyolefin-based composition for a lid and methods of making and using
AssigneeDart Container Corporation
InventorsCHENGTAO LI, ROBERT ALLAN BRUBAKER, JACOB CHRISTOPHER PURCELL
Life of this patent
Estimating the term…
Abstract
Aspects of the present disclosure relate to a polyolefin composition and processes suitable for use in forming a lid for a hot food or beverage container that has a stiffness comparable to a similar lid made using high impact polystyrene and a density less than water at 23° C.
Claims20
A thermoformed lid for a food or beverage container made from a non-vented, extruded sheet comprising at least one polyolefin with at least one filler, and having a plurality of expanded cells providing the thermoformed lid with a density greater than 0 g/cm3 at 23° C. and less than 1 g/cm3 at 23° C.
A process for forming a lid for a food or beverage container from a polyolefin-based sheet, the process comprising:
- providing a polyolefin blend comprising at least one polyolefin and at least one filler to an extruder;
- providing a blowing agent to the polyolefin blend;
- extruding, without venting, the polyolefin blend to form a polyolefin-based sheet;
- and
- at least partially expanding the polyolefin-based sheet to form an expanded polyolefin-based sheet having a plurality of expanded cells;
- and
- forming the expanded polyolefin-based sheet into the shape of a lid;
- wherein the lid has a density less than water at 23° C.
Dependencies are inferred from the claim text.