IGNITER ASSEMBLY AND MOLDING METHOD FOR HOLDING PART

An igniter assembly includes an igniter, a collar, and a holding part, a cup body having a cylindrical peripheral wall and a lid wall and a closing part defining an accommodating space with the cup body, the peripheral wall is sectioned, in an axial direction, into a contact region in contact with the closing part and a noncontact region not in contact with the closing part, the holding part includes a base part covering the contact region and a surrounding wall formed continuously to the base part and surrounding the noncontact region, and a fragile part is formed in the holding part between a first area including at least a part of the base part and a second area including a tip end of the surrounding wall, and thus the second area deforms radially outward preferentially when a load is applied to the surrounding wall by the igniter activated.