Patent ID: 11877628
Assignee: YKK CORPORATION
Field: Other consumer goods (Other fields)
Classification: CPC A | IPC A

Claim 3:
4. A method for manufacturing a watertight fastener, comprising:
attaching fastener elements (16) on a side of one end edge part (12a) along a longitudinal direction of a pair of fastener tapes (12), each having one surface (12c) and another surface (12b) to form slide fastener chains, the end edge part (12a) being folded double at a folding line (13) to overlap the one surface (12c), so that the another surface (12b) of the fastener tape (12) is convex and the fastener element (16) being provided on an another surface (12b) side of the fastener tape (12), and engaging the fastener elements (16) with each other to close the pair of slide fastener chains;
coating a synthetic resin with a predetermined width along the longitudinal direction, on the side of the end edge part (12a) of the another surface (12b) of the pair of fastener tapes (12) which is located on a side opposite to the fastener elements (16), wherein a coating width of the synthetic resin is formed to be narrower than a width of a slider (24);
curing the coated synthetic resin and cutting the synthetic resin along the end edge part (12a) to form a pair of left and right waterproof seal layers (20) of the pair of fastener tapes (12); and
afterwards, attaching the slider (24) for performing engagement and disengagement to the pair of fastener tapes (12), the pair of left and right waterproof seal layers forming one liquid-tight waterproof seal layer (20) when the fastener chains are closed, wherein the waterproof seal layer (20) does not come into contact with the fastener elements (16), and with the pair of fastener tapes (12) being closed by engagement of the fastener elements (16), end parts (20a) of the waterproof seal layer (20) close to the end edge parts (12a) of the fastener tapes (12) are flushly continuous with the folding lines (13) and shaped to come into contact with each other without overlapping each other in a thickness direction and without a gap to be in close contact in a liquid-tight manner.