| 摘要 |
PROBLEM TO BE SOLVED: To provide a cap that is prevented from being threadably engaged with a container body solidly, and is more easily threadably disengaged from the container body.SOLUTION: A knurl part 10 where a plurality of protruding ridges 12, 14 are arranged and a smooth part 30 where the protruding ridges 12, 14 are not formed are formed, a slope 20 is formed from a first base end 13c of a first plane 13a in a threadably engaged direction X1 of a leading-edge protruding ridge 13 of the knurl part 10 in the threadably engaged direction X1 to a reference plane Q1, and a first tilt angle &thetas;1 between the slope 20 and a tangent P1 to a virtual circle C1 having an axis as its center and passing the first base end 13c of the first plane 13a, is smaller than a second tilt angle &thetas;2 between a second plane 13b in a threadably disengaged direction Y1 of the leading-edge protruding ridge 13 and a tangent P2 to the virtual circle C1 having the axis as its center and passing a second base end 13d of the second plane 13b. |
