Patent ID: 6339911
Filing Date: 2002-01-22
Classification: B31B,B65D

Abstract:
A method of manufacturing packaging bags, comprising the steps of:providing a packaging bag sheet, having a longitudinal extent, for forming a packaging bag; folding said packaging bag sheet so as to form a pair of laterally spaced bellow regions within side edge portions of said packaging bag sheet; forming cutouts at a mouth region and within each one of said pair of laterally spaced, bellow regions of said packaging bag sheet so that said packaging bag has only two sheet thicknesses superimposed with respect to each other within the mouth region of said packaging bag, wherein each one of said cutout portions is defined by two rectilinear longitudinal edges coinciding respectively with outer definition lines of said laterally spaced bellow regions, a first rectilinear transverse edge extending transversely with respect to said longitudinal extent of said packaging bag sheet, and a second non-rectilinear transverse edge that is concave towards said mouth region of said packaging bag; and heat sealing edge portions of said packaging bag sheet to edge portions of said cutouts so as to close and seal said packaging bag.