Stitchless bulk bag including a baffle insert and method of production
A stitchless baffle bulk bag including one or more baffle inserts that are heat sealed to a bag body using a hot melt film. A baffle insert includes a plurality of lateral straps spaced in between longitudinal panels. Tabs extend from the longitudinal panels into the space between lateral straps, above and below the lateral straps. The hot melt film is applied to at least a portion of the longitudinal panel and to the tabs, which is then heat sealed to the body under heat and pressure of heat seal bars. A hot melt sealed tab on both sides of the strap extending beyond the pivot point of the strap counters the forces of peel encountered by the strap and/or by a heat sealed joint of the tab or longitudinal panel.
1 . A bulk bag comprising:
a) a top portion;
b) a body portion having an interior surface, and having a first side, a second side, a third side and a fourth side, and having a first corner, a second corner, a third corner and a fourth corner, in an expanded configuration;
c) a bottom portion;
d) a baffle insert portion including:
(i) at least a pair of longitudinal members with a plurality of lateral members spaced apart in between the longitudinal members;
(ii) a plurality of tab portions, each tab portion extending laterally away from one said longitudinal member and into a space in between two said lateral members or into a space above or below a said lateral member;
e) a heat-sealed joint formed between the body interior surface and the longitudinal members and formed between the plurality of tab portions and the body interior surface;
f) wherein the baffle insert is positioned in the body portion so that it extends from the first side to the second side and across the first corner of the body portion with the lateral members positioned along a diagonal across the first corner when the body portion is in the expanded configuration.
2 . The bulk bag of claim 1 wherein four baffle inserts are included in the bulk bag at the first corner, the second corner, the third corner and the fourth corner.
3 . The bulk bag of claim 2 wherein a heat seal coating extends along an exterior surface of each of the longitudinal members of the four baffle inserts and along a surface of the plurality of tab portions and forms part of the heat-sealed joint.
4 . The bulk bag of claim 3 wherein during heat sealing, the body is in a folded gusseted configuration including a pair of body gussets and the baffle insert is gusseted in a folded gusseted configuration including two baffle gussets and the baffle gussets are overlapped with the body gussets.
5 . The bulk bag of claim 2 wherein during heat sealing, the body is in a folded gusseted configuration including a pair of body gussets and two of the baffle inserts are folded and overlapped with one of the body gussets and the other two of the baffle inserts are folded and overlapped with the other body gusset.
6 . The bulk bag of claim 1 wherein the baffle insert comprises four longitudinal members and comprises an insert tubular shape and each of the four longitudinal members are coupled to the interior surface of the body so that respective lateral members extend across each of the first corner, the second corner, the third corner or the fourth corner along a diagonal.
7 . The bulk bag of claim 6 wherein a heat seal coating is on at least a portion of an exterior surface of each of the longitudinal members of the baffle insert and on the plurality of tab portions, and forms part of the heat-sealed joint.
8 . The bulk bag of claim 1 wherein during heat sealing to form the heat-sealed joint, the body is in a folded gusseted configuration including a pair of body gussets and the baffle insert is folded and overlapped with at least one of the body gussets, and heat and pressure is applied.
9 . The bulk bag of claim 1 wherein the plurality of tabs counter peel forces exerted on the joint when the bulk bag is filled with bulk material and/or lifted.
10 . The bulk bag of claim 9 wherein each tab extends at least 2 inches laterally away from the longitudinal member and into the space above or below a said lateral member.
11 . The bulk bag of claim 1 wherein the baffle insert counters both peel and tensile forces exerted on the joint when the bulk bag is filled with bulk material and/or lifted.
12 . The bulk bag of claim 1 wherein said tabs that are on both sides of one said lateral member extend beyond a pivot point of said lateral member at a junction of said lateral member and the longitudinal member and counter forces of peel encountered by said lateral member and the longitudinal member.
13 . The bulk bag of claim 1 wherein said lateral members are free and are not connected to the body.
14 . The bulk bag of claim 13 wherein the plurality of tabs protect the joint at a pivot point located where one said lateral member that is free extends away from one said longitudinal member that is coupled to the body at the joint.
15 . The bulk bag of claim 1 wherein the body is connected to the top portion and to the bottom portion with heat sealed joints.
16 . The bulk bag of claim 1 wherein the body is connected to the top portion and to the bottom portion with stitched seams.
17 . A stitchless baffle body portion comprising:
a) a body that has a tubular shape and comprises flexible plastic fabric or polyester fabric, the body having an interior surface, a first side, a second side, a third side and a fourth side, a first corner, a second corner, a third corner and a fourth corner, and the body having an expanded configuration;
b) one or more baffle inserts made from a flexible plastic fabric or a polyester fabric that include:
(i) at least a pair of longitudinal members with a plurality of lateral members spaced in between the longitudinal members;
(ii) a plurality of tab portions, each tab portion extending laterally away from one said longitudinal member and into a space in between two said lateral members, or into a space above or below a said lateral member;
c) one or more heat sealed joints coupling the one or more baffle inserts to the interior surface of the body; and
d) wherein at least a portion of the plurality of lateral members are free and not coupled to the body.
18 . A heat sealing method of manufacturing a baffle bulk bag comprising the following steps:
a) overlapping an upper portion of the baffle body portion of claim 17 while in a baffle folded or gusseted configuration with a top portion while the top portion is in a top folded or gusseted configuration so that a baffle body heat seal coating on an exterior surface of the baffle body portion is in contact with a top heat seal coating on an interior surface of the top portion;
b) overlapping a lower portion of the baffle body portion of claim 17 while in the baffle folded or gusseted configuration with a bottom portion while the bottom portion is in a bottom folded or gusseted configuration so that the baffle body heat seal coating on the exterior surface of the baffle body portion is in contact with a bottom heat seal coating on an interior surface of the bottom portion; and
(c) applying heat and pressure to overlapped layers formed in steps (a) and (b) to melt at least one of the baffle body heat seal coating or top heat seal coating in the overlapped layers of step (a) and to melt at least one of the baffle body heat seal coating or bottom heat seal coating in the overlapped layers of step (b) to form a top heat sealed joint between the baffle body portion and the top portion and a bottom heat sealed joint between the baffle body portion and the bottom portion.
19 . The bulk bag of claim 18 wherein the top portion, the body portion, the baffle insert and the bottom portion are made from flexible plastic fabric or polyester fabric.
20 . A bulk bag comprising:
a) a body portion having an interior surface, and having a first side, a second side, a third side and a fourth side, and a first corner, a second corner, a third corner and a fourth corner, in an expanded configuration;
b) a bottom portion;
c) a baffle insert portion including:
(i) a pair of longitudinal members with a plurality of lateral members spaced in between the longitudinal members;
(ii) a plurality of tab portions, each tab portion extending laterally away from one said longitudinal member and into a space in between two said lateral members or into a space above or below a said lateral member;
d) a heat sealed joint, formed between the body interior surface and the pair of longitudinal members and between the body interior surface and the tabs; and
e) wherein the baffle insert is positioned in the body portion so that it extends from the first side to the second side and across the first corner of the body portion with the lateral members positioned along a diagonal across the first corner when the body portion is in the expanded configuration.