Patent attributes
A thermally insulated cup is formed from a single-walled paper or plastic inner cup and an insulating outer wrapper. The insulating outer wrapper comprises a paper base sheet or outer sidewall blank, optionally printed on one side, and a corrugated paper or foamed plastic insulating insert. The insulating insert is similar in shape to the outer sidewall blank but smaller in size. The insert is glued in a centered position to the non-printed side of the sidewall blank to form a two-layered insulating wrapper. Less than 20% of the area of the insert is glued to the base sheet. Specifically, no glue is applied to the area adjacent to the cut side edges of the insert, and as such these edges are not attached to the base sheet. The wrapper is then wrapped around the single walled inner cup. The side edges of the base sheet of the wrapper overlap and are sealed directly together to form a side seam. The side seam is itself adhesively secured to the side wall of the inner cup. The side edges of the insert do not come between the seal between the side seam of the base sheet and the inner cup. The wrapper can also be adhered to the inner cup by one or more beads of cold glue (paste adhesive) or a thin layer of polyethylene (or similar heat sealing material) can be pre-applied to the inside cut edges of the base sheet. This is then heat-activated immediately prior to wrapping the wrapper around the inner cup, and pressing the overlapping side seam to the sidewall of the inner cup to simultaneously glue the side seam together, and to glue the insulating wrapper to the side wall of the cup.
