BURST PLATE FOR INFLATOR

The present invention provides a ruptuable plate in which broken pieces are hardly produced. In an inflator for inflating an article to be infalted with a pressurized medium, a rupturable plate for an inflator blocking and closing between a portion which is charged with a pressurized medium and maintained at high pressure and a portion which is not charged with a pressurized medium and maintained at normal pressure is provided. The rupturable plate is mounted to the inflator by fixing a peripheral edge portion thereof to the inflator, and is further provided with one or two or more selected from the followings: (a) a ratio (diameter/thickness) of a thickness and a diameter is 14 to 50, (b) a tensile strength is 880 to 1100 N/mm, and (c) an elongation is 25% or more. And in the rupturable plate, the whole remaining portion excluding the fixed peripheral edge portion falls off without breaking when the rupturable plate receives a pressure of the igniter.