| 摘要 |
PURPOSE:To provide a wrinkle-free lid by cooling the lid member for more than specified time, keeping compressive conditions after bonding a heat-sealing member with heat to the periphery of an opening, with applying a compressive force to lessen the container height. CONSTITUTION:A heat sealing member 1 is lightly drawn in advance to make a cap-form with wrinkles at the side thereof. A container 2 set by a lid member 1 is positioned between upper and lower headers 6, 7 and subjected to a compressive force in the vertical direction. Here the compressive strain of the container 2 is preferably less than 2.0mm in the container height. Next, high frequency current is ordinally applied to bond the lid member with heat the periphery of the container opening 2a. The lid member is cooled for more than 0.5 sec. to solidify the heat sealing layer after halting application of high frequency current, being subjected to the compressive force. In this way, wrinkle are restrained from generating by preventing deformation near the container opening 2a against a suction force resulting from decompression at the vacant portion 5 and by preventing the buckling of the heat sealing lid member 1 with fastening the heat sealing member 1. |
