Coated paper beaker with sealed thermoplastics lid - has weak filler material in hollow adjacent top of side wall seam

摘要

Paper beaker of coated material has a lapped (vertical) wall seam which continues into the curled-over edge rim of the beaker. A thermoplastics cover is sealed onto the rim and the hollow corner between this cover and the rim in the region of the seam is filled with a thermoplastics material having a lower strength than the material with which the paper is coated. More specifically, this material has low viscosity when melted. Preferably it is a wax. This arrangement means that when the beaker is opened by pulling off the top there is less risk of the coating being pulled off the saturated paper or a saturated region of the rim kinking. A typical coating material (not claimed) for the paper is polyethylene.