| 摘要 |
<p>A heat sealing element, for sealing and simultaneously cutting through at least two layers of thermoplastic film (29) is disclosed. It is particularly adapted for use with a vertical form, fill and seal machine for packaging flowable materials, e.g. chocolate fudge sundae topping, in a lap seamed pouch. The heat sealing element (12) has a portion (33), which has a greater electrical resistance than the remainder of the element, at the position where the lap seal is to be formed. The portion which has a greater electrical resistance is preferably a portion which is narrower than the remainder of the element, preferably 83 to 94 % of the width of the remainder of the element.</p> |
