US 12,187,511 B2
Multi-film thermoplastic bags having hem seals comprised of continuous contact areas and methods of making the same
Sarah J. Steenblock, Cincinnati, OH (US); Matthew W. Waldron, West Chester, OH (US); Karen McAffry, Willowbrook, IL (US); Edward B. Tucker, Willowbrook, IL (US); and Shaun T. Broering, Fort Thomas, KY (US)
Assigned to The Glad Products Company, Oakland, CA (US)
Filed by THE GLAD PRODUCTS COMPANY, Oakland, CA (US)
Filed on Jun. 6, 2023, as Appl. No. 18/330,138.
Application 18/330,138 is a continuation of application No. 17/585,211, filed on Jan. 26, 2022, granted, now 11,814,225.
Application 17/585,211 is a continuation in part of application No. 17/167,390, filed on Feb. 4, 2021, granted, now 11,970,310.
Application 17/167,390 is a continuation in part of application No. PCT/US2020/024143, filed on Mar. 23, 2020.
Claims priority of provisional application 62/825,520, filed on Mar. 28, 2019.
Prior Publication US 2023/0312201 A1, Oct. 5, 2023
Int. Cl. B65D 65/40 (2006.01); B32B 7/05 (2019.01); B32B 7/10 (2006.01); B32B 37/10 (2006.01); B32B 38/06 (2006.01); B65D 27/00 (2006.01); B65D 33/28 (2006.01)
CPC B65D 65/40 (2013.01) [B32B 7/05 (2019.01); B32B 7/10 (2013.01); B32B 37/10 (2013.01); B32B 38/06 (2013.01); B65D 27/00 (2013.01); B32B 2250/02 (2013.01); B32B 2250/24 (2013.01); B32B 2307/4026 (2013.01); B32B 2439/46 (2013.01); B65D 33/28 (2013.01); B65D 2203/00 (2013.01)] 20 Claims
OG exemplary drawing
 
1. 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.