| 摘要 |
A gas barrier folding carton formed from a unitary paperboard blank (10) having a gas impermeable polymer layer (52) such as EVOH, nylon, or foil extruded on or laminated to one surface of the blank, except for certain abhesive (56, 58) coated areas. Two opposite side edges of the blank are seamed to form a flattened tube (13) having top and bottom closure flaps (30, 34, 36, 38, 40). One of the major closure flaps (36) at each top and bottom container end is provided with spaced abhesive areas (58), with areas of the two minor closure flaps (34, 38) also provided with abhesive (56). Upon folding the closure flaps at each end, the folding sequence pulls the barrier film (52) away from the abhesive (56, 58) areas and subsequent heat sealing produces hermetic sealing of the carton. This process and carton construction may be employed with conventional gas purging of the container interior by an inert gas before final sealing.
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