| 摘要 |
PURPOSE: Provided is a reclosable zipper for use in reclosable plastic bags and packages. More particularly, a reclosable zipper having a fusible rib layer on each profile. Thereby a stronger seal between the zipper and package material, a lower sealing temperature and a faster sealing time are achieved. CONSTITUTION: A reclosable zipper 74 has a male profile 76 interlockable with a female profile 78. The male profile 76 includes a male interlocking member 80 in the shape of an asymmetrical arrow extending from a base 82. Likewise, the female profile 78 includes a U-shaped female interlocking member 84 interlockable with the male interlocking member 80 extending from a base 86. The male interlocking member 80 is provided with an asymmetrical arrow shape so that the zipper 74 is more difficult to open from one side of the zipper (the right side of the zipper) than the other. The profile bases 82, 86 extend on either side of their respective interlocking members 80, 84 so as to form flanges 88. The flanges 88 facilitate feeding and guiding of the zipper 74 during automated package making processes, such as on a form-fill-and seal machine, and serve as the point of sealing of the profiles to the package material. Each profile base 82, 86 is provided with a continuous fusible rib layer 90 on a surface 91, 93 directed away from its respective interlocking member 80, 84 for sealing the zipper profiles 76, 78 to the package material. The fusible rib layer 90 is a continuous layer which, preferably, is co-extruded with the zipper profiles 76, 78 and is formed from any one of many commercially available sealants well known to those of ordinary skill in the art. The sealant is preferably of the kind which is suitable for low temperature sealing applications. If desired, the sealant layer can be formed of a heat activated adhesive compatible with both the package material and the zipper. The fusible rib layer 90 is comprised of a single layer of sealant in a pattern of alternating peaks (triangular fusible ribs 92) and valleys (planar portions 94). |
