Abstract: A web of packaging material made of heat sealable plastic sheeting has two parallel rows of cover portions sealed to the outer surface of the sheeting and arranged eccentrically to the longitudinal center of the web. The cover portions are made of a material which is stiffer than the plastic sheeting and which can be welded to it, preferably plastic coated cardboard or paper. Each cover portion is of approximately equal size and shape and are equally spaced longitudinally along the web. At least one row of cover portions is preferably sealed to the plastic sheeting by an inner cover strip at a surface eccentric to the geometric center of the cover portion and includes a ring pull to facilitate the opening of a subsequently formed package. In an alternate embodiment, only one row of cover portions is sealed to the outer surface of the web along the longitudinal center.

Abstract: For the purpose of producing a packing container a web of laminated material is used, which material includes a base layer of foamed polystyrene, and two outer layers of homogeneous polystyrene.In order to seal the edge zones of the material web into a tube a part of the base layer of one of the edge zones is removed and the other edge zone is inserted into this cut off part between the remaining end parts of the outer layers and is heat-sealed to the outer layers. The so achieved sealing is tight and durable and superior to the known overlap sealing. The seal is also more pleasing from the aesthetic point of view.