Bag with gripping bands
View Patent ↗A closure for closing a bag and a die head and method for making the closure. The closure includes two closure members having support walls and mating interlocking profiles. The support walls are resilient and have self-retaining forms in vertical section including middle sections curving outwardly away from one another when mounted on a bag. Top portions of the support walls extend outwardly away from one another to form gripping panels when the closure is closed. A die head for forming a closure member includes a body that defines a slot including a support wall segment for forming the support wall of the closure member. The support wall segment includes first and second portions oriented transverse to one another and intersecting at a vertex. To form the closure member, polymer is extruded through the slot and quenched.
1. A closure for selectively closing a bag that is configured to facilitate opening of the bag when the bag is closed by the closure, the closure comprising:
first and second closure members configured for mounting on the bag in opposed relation for releasably closing the bag, each closure member comprising:
a support wall having a top end and a bottom end spaced apart along a height and a first side and a second side spaced apart along a width; and
an interlocking profile extending along the width of the respective support wall at a location spaced apart from the top end of the support wall, the interlocking profile being configured for selective complementary interlocking engagement with the interlocking profile of the other closure member to close the closure;
each support wall being resilient and having a self-retaining form in vertical section, the form extending continuously along a majority of the width of the support wall and including a top portion adjacent the top end, a bottom portion adjacent the bottom end, and a curved middle portion between the top portion and the bottom portion,
wherein when the first and second closure members are mounted on the bag, the middle portions of the support walls curve outwardly away from one another as they extend upward toward the top portions of the support walls and the top portions of the support walls extend outwardly away from one another as they extend upward from the middle portions to form gripping panels that are spaced apart from one another by a gap that extends continuously along the majority of the width of at least one of the support walls when the closure is closed; and
wherein the bottom portion of the support wall of the first closure member has a resilient and self-retaining serpentine cross-sectional profile.
2. A closure as set forth in claim 1 wherein the top portions of the support walls are each shaped and arranged to define an angle between the support wall and a vertical axis in an inclusive range of from about 10° to about 70°.
3. A closure as set forth in claim 1 wherein the middle portions of the support walls each have a radius of curvature in an inclusive range of from about 1 cm to about 3 cm.
4. A closure as set forth in claim 1 wherein the cross-sectional profile of the top portion of each of the support walls is substantially straight.
5. A closure as set forth in claim 1 wherein the tops of the support walls define a gap therebetween when the closure is closed, said gap having a maximum width in an inclusive range of from about 0.2 cm to about 3.0 cm.
6. A closure as set forth in claim 1 wherein the bottom portion of the support wall of the first closure member has at least one segment extending outward as it extends upward.
7. A closure as set forth in claim 1 wherein each of the first and second closure members comprises an urging projection extending inward from the middle portion of the respective support wall along the width of the support wall.
8. A closure as set forth in claim 7 wherein the urging projections are shaped and arranged for interfering engagement with each other when the closure is closed.
9. A closure as set forth in claim 7 wherein the urging projections engage one another when the closure is closed and thereby urge the top portions of the support walls outward away from each other.
10. A closure as set forth in claim 1 wherein the interlocking profiles of the first and second closure members are configured to require a substantially greater separation force to disengage the interlocking profiles when the separation force is imparted on the bottom portions of the support walls than when the separation force is imparted on the top portions of the support walls.
11. A closure member as set forth in claim 1 wherein each of the first and second closure members further comprises a plurality of gripping projections extending along the width of the support wall at spaced apart locations along the top portion of the respective support wall.
12. A bag comprising a bag body and a closure as set forth in claim 1 joined to a top edge margin of the bag body.