Abstract: In a die-cut cardboard blank coated on at least one side with plastic and/or aluminum foil and capable of being folded into a liquid packaging container having a planar, rectangular folded bottom sealed in a liquid-tight manner with an overlapped seam and a protected edge on the inner bottom fold-in panel, the improvement which comprises providing the blank with an inner bottom fold-in panel having in its marginal area a die-cut notch extending beyond the visible area when folded, this notch being filmed over with the coating material. Alternatively, the blank may be provided with an inner bottom and triangular fold flaps, the triangular fold flaps having tips which in folded condition abut one another and cover the inner bottom fold-in panel, the tips being die-cut and filmed over with coating material.

Abstract: In a blank for folding into a parallelepipedal package that is intended for liquids, the blank having an area that is to be folded into a double-M closure for a gable-shape top having inwardly folded opposite triangular sections and a middle fold line, the improvement which comprises providing each of said opposite triangular sections with a slit that slants from the upper edge down to or slightly beyond the middle fold line, whereby the folded package has an improved seal. When the cross-section is square, the slits should be parallel so that the folded areas dogleg and overlap.