Heat activated adhesives for bag closures

In a woven bag of polymeric material, the bag having a first panel, the first panel being foldable along a fold line of the first panel, and the bag having an adhesive coated surface on the first panel for adhesively bonding with an exposed portion of a second panel, the improvement comprising:

• the adhesive coated surface on the first panel comprising a heat activated adhesive layer on a panel section above the fold line of the first panel, and on a further panel section below the fold line of the first panel, which is in combination with heat activated further adhesive material on a flap portion, the exposed portion of the second panel and exposed portions of gussets;
• the adhesive layer and the further adhesive material have respective heat activation melt temperatures below about 300° F. and below the softening point temperature of the polymeric material;
• the heat activated adhesive layer on the further panel section below the fold line providing an adhesive-to-adhesive seal with the heat activated adhesive layer on the panel section above the fold line while the bag is folded;
• the heat activated further adhesive material on the flap portion, the exposed portion of the second panel and the exposed portions of the gussets providing a further adhesive-to-adhesive seal with the heat activated adhesive layer on the further panel section below the fold line, while the flap portion is folded onto the further panel section below the fold line, to hold the bag in a folded configuration by the further adhesive-to-adhesive seal;
• and
• said adhesive-to-adhesive seal and said further adhesive-to-adhesive seal, resisting opening while the bag is filled with 50 lbs. of contents and, dropped on the first panel from a height of 4 feet and dropped on the second panel from a height of 4 feet, and further, resisting creep while the bag is suspended while filled with 20 lbs. of contents and subjected to an environment of Zero degrees F. for 72 hrs. and an environment of 140 degrees F. at 70% relative humidity for 72 hrs., and further, resisting peel and shear over a temperature range of −20 degrees F. to +140 degrees F.