Multi-film thermoplastic bags having hem seals comprised of continuous contact areas and methods of making the same
AssigneeThe Glad Products Company
InventorsSarah J. Steenblock, Matthew W. Waldron, Karen McAffry, Edward B. Tucker, Shaun T. Broering
Life of this patent
Estimating the term…
Abstract
One or more implementations of a multi-film thermoplastic structure include a first film having a first appearance in contact with a second film having a second appearance at one or more visually distinct contact areas, including a continuous contact area spanning a width of the structure. In one or more implementations the multi-film thermoplastic structure comprises a thermoplastic bag and the continuous contact area forms a hem seal near a top opening of the thermoplastic bag.
Claims20
A multi-layer thermoplastic bag comprising:
- an outer first thermoplastic bag comprising first and second opposing sidewalls joined together along a first side edge, an opposite second side edge, an open first top edge, and a closed first bottom edge;
- an inner second thermoplastic bag positioned within the outer first thermoplastic bag, the inner second thermoplastic bag comprising third and fourth opposing sidewalls joined together along a third side edge, an opposite fourth side edge, an open second top edge, and a closed second bottom edge;
- and
- the open first top edge and the open second top edge folded over and secured by a hem seal to form a hem channel, wherein:
- the hem seal extends between the first and second side edges with a substantially uniform width on an outside face of the multi-layer thermoplastic bag, and
- the hem seal comprises a lamination gradient such that a lamination strength of the hem seal decreases in a direction extending away from a central longitudinal axis of the hem seal, and
- the lamination strength of the hem seal at the central longitudinal axis of the hem seal is 2 to 5 times greater than the lamination strength of the hem seal at borders of the hem seal.
A thermoplastic bag comprising:
- a first sidewall and an opposing second sidewall of a thermoplastic material, the first and second sidewalls connected at a bottom fold and at opposing first and second side edges;
- a top opening formed by the first and second sidewalls opposite the bottom fold;
- and
- the top opening comprising a first top edge of the first sidewall and a second top edge of the second sidewall folded over and secured by a hem seal to form a hem channel, wherein:
- the hem seal extends between the first and second side edges with a substantially uniform width on an outside face of the thermoplastic bag,
- the hem seal comprises a lamination gradient such that a lamination strength of the hem seal decreases in a direction extending away from a central longitudinal axis of the hem seal, and
- the lamination strength of the hem seal at the central longitudinal axis of the hem seal is 2 to 5 times greater than the lamination strength of the hem seal at borders of the hem seal.
Dependencies are inferred from the claim text.