Metallic container closure having internal pressure release function

摘要

A metallic container closure comprising a shell of a thin metal sheet having a circular top panel wall 7 and a skirt wall 9, and a synthetic resin liner arranged in the shell, the skirt wall 9 having a thread-forming region and an annular groove 17 positioned at an upper end portion of the thread-forming region, wherein an internal pressure release line A extending in the circumferential direction is arranged in the skirt wall 9 at a portion over the annular groove 17, and annular bead 30 is arranged so as to pass through between the internal pressure release line A and the annular groove 17. The metallic container closure effectively releases the gas when the pressure in the container is elevated and effectively prevents the skirt wall from being deformed at a portion where the internal pressure release line A is formed when it is being wrap-seamed with the mouth-and-neck portion of the container.