Easy-open flexible pouch and apparatus and method for making same
AssigneeW. R. Grace & Co.
InventorDennis J. Vogan
Life of this patent
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Abstract
A pouch and a method and apparatus for forming an easy open pouch in a vertical form-fill-seal process wherein a pouch is formed from a sheet of thermoplastic film and a heat seal between pouches as they are filled serves as the top closure for the lower pouch and a bottom closure for the upper pouch, the easy open feature being provided by a U-shaped portion having a plurality of seal ribs, and a tear initiation notch.
Claims1
In the vertical form-fill-seal method of making and filling a pouch by forming a tube from thermoplastic film, transversely heat sealing the tube to close its bottom end, filling the tube, transversely heat sealing across the tube at a preselected spacing to form an upper seal for the filled bag then cooling the seal and transversely severing the seal approximately the midpoint of the vertical width of the seal to separate a lower, filled pouch from a next or upper pouch, the improvement which comprises the steps of:
- (a) forming a plurality of parallel, spaced apart seal ribs disposed in a substantially U-shaped arrangement along a portion of said upper heat seal around a U-shaped unsealed area;
- and
- (b) simultaneously with step (a), making a series of notches within the seal ribs of said upper seal, said series of notches extending from a side edge of the pouch towards the U-shaped unsealed area of the seal intermediate the height of the U-shaped portion.
Dependencies are inferred from the claim text.