Patent ID: 6938793

Claim:
A combination of a thermal preservation insert and a plastic food container, comprising: a plastic food container including a bottom with a periphery and a container wall, said container wall having a tapered lower portion with an inner surface that meets the periphery of the bottom, the inner surface having a shape, the tapered lowered portion being tapered around its entire inner surface, a thermal preservation insert comprising: a disk, the disk containing a thermal preservation fluid completely buried inside the disk, the disk having a lower surface that conforms identically to the periphery of the bottom of the plastic food container and having a tapered side that conforms identically to the shape of the inner surface of the lower portion of the container wall of the plastic food container, the lower surface of the disk resting on the bottom of the plastic food container and the side of the disk resting snugly against the lower portion of the container wall, said disk not fastened to a part of the plastic container.