Patent ID: 8539650

Claim:
A slide fastener comprising: a pair of left and right fastener tapes; and a plurality of synthetic resin fastener elements lined along opposing tape side edge portions of the fastener tapes, each fastener element including an upper half element portion disposed at a first surface side of the fastener tape and a lower half element portion disposed at a second surface side of the fastener tape, the upper half element portion including a first tape-sandwiching portion having a predetermined dimension in a tape length direction, and a first head portion of a tapered form that extends from the first tape-sandwiching portion toward an outside of the tape to a forefront portion of the lower half element portion and has a dimension in the tape length direction that gradually decreases toward the forefront, the lower half element portion including a second tape-sandwiching portion that sandwiches the fastener tape together with the first tape-sandwiching portion, a neck that extends from the second tape-sandwiching portion toward the outside of the tape and has a shape constricted in a front and rear of the tape length direction, and a second head portion that extends from a forefront portion of the neck and bulges in a front and rear of the tape length direction, and wherein the upper half element portion has a tapered portion in which a dimension between front and rear side surfaces of at least the first tape-sandwiching portion in the tape length direction gradually decreases as it goes upward, wherein the upper half element portion has a thin walled portion in which a height dimension of the fastener element at a forefront portion of the first head portion in a vertical direction of the fastener element is smaller than a height dimension of the fastener element at a thin walled start portion, and wherein the thin walled portion includes a downward inclined surface that is continuously inclined downward to gradually decrease in a height dimension of the fastener element from the thin walled start portion to the forefront portion of the first head portion.