Abstract: The invention relates to a method for manufacturing packs (1) characterized in that it comprises steps according to which: a packaging film is unwound; a first gusset is formed on the unwinding packaging film; a second gusset is formed on the unwinding packaging film, the second gusset being formed on the same edge of the unwinding film as the first gusset (3), said second gusset being associated with a closure assembly to form an opening indicator.

Abstract: The invention relates to a method for manufacturing packs (1) characterised in that it comprises steps according to which:

Abstract: The present invention relates to a method of manufacturing packaging bags having lateral bellows, the method being characterized by the fact that it comprises the steps consisting in: forming respective cutouts (150, 160) in each of the two lateral, bellows-forming zones of a packaging bag sheet (100) so that the bag has only two thicknesses superposed at the mouth of said bellows, at least over a portion of its width; and heat-sealing (184, 186) the adjacent edges of the sheet to the peripheries of the cutouts (150, 160) to close the bag. The invention also provides apparatus for implementing the method and bags obtained thereby.