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
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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.
Claims32
A thermoformed lid for a food or beverage container, the thermoformed lid made from a non-vented, extruded sheet comprising at least one polyolefin with at least one filler, and having 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 thermoformed lid for a food or beverage container, the thermoformed lid made from a non-vented, extruded and expanded sheet comprising a polyolefin blend having at least one polyolefin and at least one filler, a blowing agent, and having a plurality of expanded cells with an average cell diameter in a range of 0.01 to 0.15 mm, and a density less than water at 23° C.
A thermoformed lid for a food or beverage container, the thermoformed lid made from a non-vented, extruded, and expanded sheet comprising a polyolefin blend having at least one polyolefin and at least one filler, a blowing agent, a plurality of expanded cells providing the thermoformed lid with a density less than water at 23° C., and at least one of:
- a stiffness of the thermoformed lid is comparable to a similar lid made from unexpanded high impact polystyrene, and wherein stiffness is based on a weight required to induce a 0.25 inch deflection of the thermoformed lid when the thermoformed lid is placed on a cup holding liquid at 200° F.;
- a shrinkage rate of 1.3 to 1.5% during storage;
- or
- combinations thereof.
A thermoformed lid for a food or beverage container, the thermoformed lid made from a non-vented, extruded sheet comprising a polyolefin blend having at least one polyolefin and at least one filler, a blowing agent, with the sheet being at least partially expanded to form a plurality of expanded cells, wherein the thermoformed lid has a density in a range of 0.900 to 0.999 g/cm3 at 23° C.
A thermoformed lid for a food or beverage container, the thermoformed lid made from a non-vented, at least partially expanded sheet comprising a polyolefin blend with at least one polyolefin with at least one filler, a plurality of expanded cells, and a blowing agent, wherein the blowing agent is at least one of:
- selected from the group consisting of sodium bicarbonate, sodium carbonate, ammonium bicarbonate, ammonium carbonate, and ammonium nitrite;
- present in an amount of 0.2 to 3 wt. %;
- or
- combinations thereof;
- wherein the thermoformed lid has a density less than water at 23° C.
Dependencies are inferred from the claim text.