Patent ID: 7464856

Claim:
A container blank, comprising: a paperboard substrate layer suitable for forming a sidewall of a container, wherein the substrate layer has an interior and an exterior as well as upper and lower substrate layer portions corresponding to upper and lower portions of the container sidewall; a layer consisting essentially of a single shrink film layer secured to the interior of the substrate layer on both the upper and lower portions of the substrate layer, wherein the shrink film layer is adapted to shrink away from the substrate layer upon application of heat thereto, thereby providing a shrunk film layer secured to the interior of the substrate layer on both its upper and lower portions after heat is applied to the shrink film layer; and whereby the shrunk film layer provides at least one thermal insulating pocket between the substrate layer and the shrunk film layer and wherein the shrunk film layer is secured to both the upper and lower portions of the container sidewall when present on an interior of a container.