Patent ID: 8590117

Claim:
A slide fastener, comprising: a plurality of attachment leg portions of coupling teeth, on each of which, a coupling head formed to have a relatively large width and the attachment leg portions extending from the coupling head are formed, are attached on a coupling tooth attaching portion of each of a pair of fastener tapes on right and left with a predetermined pitch P [mm] along a tape longitudinal direction, and wherein the coupling teeth are formed by injection molding or made of coil-shape or zigzag-shape mono-filament, wherein relationships among a summit height H [mm] of the coupling head formed to have a relatively large width, coupling tooth thickness T [mm] of the coupling head, and a pitch P [mm] satisfy both of the following: 0.4≧(2 ×H−P )/ P≧ 0.1 0.2≧(2 ×H−P )× T /(2 ×P ) where (2×H−P)/P expresses a coupled ratio and (2×H−P)×T/(2×P) expresses a coupled sectional amount, and wherein the coupling teeth are configured so that when a lateral pulling force of 40 N/cm or more is applied as a force per a unit length of a coupling line in a direction which is orthogonal to a coupling axis and a direction to separate the pair of the fastener tapes on right and left in a state where the coupling teeth attached to each of the pair of the fastener tapes are coupled with each other along the coupling axis, the coupling of the coupling teeth is released.