Verfahren zur Herstellung eines wasserdichten Reißverschlusses

摘要

PCT No. PCT/DE92/00688 Sec. 371 Date Mar. 3, 1994 Sec. 102(e) Date Mar. 3, 1994 PCT Filed Aug. 17, 1992 PCT Pub. No. WO93/04605 PCT Pub. Date Mar. 18, 1993.A waterproof zip closure is formed by extruding a first thermoplastic material onto its teeth, and applying a transverse force while the first thermoplastic material cures. The transverse force is sufficient to move the teeth in the separating direction, but is less than that which can cause separation. After curing of the thermoplastic material, the tapes and teeth of the zip closure are coated with a second thermoplastic sealing material, while the transverse force is maintained. When the transverse force is removed the sealing material is forced together to provide a waterproof seal. The second thermoplastic sealing material on the tapes further improves the waterproof nature of the zip closure.