Abstract: A multiwall cooler bag is formed by gusseted inner and outer tubes, the outer tube being made of kraft paper and having its lower end circumferentially bonded to the inner tube, the inner tube comprising an inner ply of plastic material heat sealed to closure at its lower end and an outer ply of kraft paper, with a strip of plastic reinforcing material extending the length of and secured to the back and front walls of the outer tube. The front wall of the outer tube has its lower end formed with a closure flap secured to the back wall of the outer tube, while the back wall of the outer tube has its upper end formed with a closure flap overlapping the front wall when the bag is completely closed. The upper portion of the inner tube is free of the outer tube to permit independent closing of the inner tube before closing the outer tube.

Abstract: A multi-ply, gusseted, stepped end, pinch bottom bag is disclosed which includes a sleeved valve in a corner of one end for receiving a filling spout from a product dispensing machine. The valve is completely sift-proof and is constructed without making changes in the cut shape and relationship of the various plies of the bag to accommodate the valve sleeve. The bag is made from a plurality of plies of flexible material, such as kraft paper, which are cut and scored to permit a multiwall, gusseted, stepped end, pinch bottom bag to be formed and to further permit a valve area to be formed at one corner when the front wall, rear wall and gusset panels in that region are infolded. The valve sleeve which is inserted into the valve area includes a tuck-in flap which is sized and shaped to correspond to the pocket formed when the wall and gusset panels are folded back against the inside walls of the bag.