METHOD AND APPARATUS FOR PRODUCING BAG WITH MOUTH MEMBER

摘要

A method is provided for producing a bag with a mouth member (1) by liquidtightly melt-bonding a mouth member (1) comprising a thermoplastic resin and a bag unit comprising a relatively soft flexible film (2), in which uniform surface temperature of the mouth member (1) is realized, generation of an A-shaped gap (22) is prevented, and a bag with a mouth member (1) excellent in the liquidtightness of the meltbonded part between the mouth member (1) and the bag unit is produced; and also a production apparatus therefor is provided. The method comprises a preheating step of heating a tubular mouth member (1) while rotating it around the cylinder axis thereof, and a melt-bonding step of inserting the heated mouth member (1) into the opening part of a bag unit and pressing, and thereby melt-bonding the mouth member (1) to the opening part of the bag unit.