Thermoplastic bag closure
AssigneeTenneco Plastics Company
InventorsRichard E. Leone, William J. Randolph
Life of this patent
Estimating the term…
Abstract
The invention relates to a bag closure for a thermoplastic grocery bag. Integral closure tabs are formed in the bag front and rear walls at the bag mouth. After the bag has been loaded, the front wall closure tab is pulled across the bag open mouth towards the rear of the bag. The rear wall closure tab is then pulled in the opposite direction across the bag mouth towards the front of the bag to engage an adhesive zone positioned on the exterior surface of the front wall. The adhesive zone is made up of a low tack, high-shear adhesive and is positioned just below the bag mouth. The adhesive zone resists shear forces generated while the bag is closed but releases easily when the rear closure tab is pulled in a direction normal to the bag wall.
Claims12
A pack of thermoplastic bags, the bags being in at least approximate registration, each bag comprising:
- (a) a front wall having an exterior surface;
- (b) an adhesion zone located on the exterior surface of the front wall;
- (c) a rear wall having an exterior surface, wherein at least a portion of the rear wall exterior surface is free of corona discharge treatment, the portion being in substantial alignment with the adhesion zone of a following bag in the pack;
- (d) gusseted side walls connecting the front and rear walls;
- (e) an open bag mouth defined by the front wall, rear wall and side walls;
- and
- (f) a first closure integral with the front wall and positioned at the bag open mouth and a second closure integral with the rear wall and positioned at the bag open mouth,
- whereby the first closure and the second closure are adapted to close the open bag mouth by the engagement of the second closure with the adhesive zone.
In a bag pack comprising a stacked series of handled flexible thermoplastic bags, each having front and back walls, each of the front and back walls having exterior surfaces and a mouth portion disposed between lateral handles, the improvement which comprises:
- a front closure tab disposed at the bag mouth and extending outwardly from the front wall;
- an adhesive material having low tack and high shear strength properties overlying at least a portion of the exterior surface of the front wall;
- and
- a rear closure tab disposed at the bag mouth opposite the front closure tab extending outwardly from the rear wall and adapted for cooperation with the front closure tab during closure,
- wherein the rear wall exterior surface is substantially free of corona treatment in a zone opposite the adhesive material of a following bag to minimize incidental adhesive contact between adjacent serial bags in the stacks.
Dependencies are inferred from the claim text.