METHOD FOR MANUFACTURING OF PACKAGING-CONTAINER BLANKS

摘要

A method of manufacturing packaging-container blanks is disclosed which method includes forming a substantially continuous sheet of blanks which sheet comprises a substrate and a coaling material attached to said substrate. The coating material at the edges of the blanks of said sheet either extends beyond the substrate or is unattached to the substrate adjacent the edge, or both. The sheet of blanks is manufactured by extruding a molten thermoplastic coating material onto the substrate between two revolving cylindrical rolls. The substrate and the coating material are joined in such a manner that at spaced, selected intervals, elongated zones are provided where they are unattached to each other. These unattached zones include zones extending transversely with respect to the sheet of blanks and which transversely extending unattached zones are produced by grooves on the periphery of at least one of the rolls which grooves are suitably arranged at intervals about the periphery of the roll to correspond to the pre-selected unattached zones desired. The substrate is perforated transversely within the unattached zones so that it may be parted after the coating material is applied by means of a longitudinal jerk. The coating material is cut along the zone by means of blades arranged in the grooves on the grooved roll. Such blades arranged in the grooves may also be used to cut the substrate if desired rather than using the perforated-jerk arrangement. Longitudinally extending unattached zones are also contemplated. Also disclosed is an apparatus for performing the above method.