Patent ID: 7695540

Claim:
A plugged honeycomb structure comprising: a columnar honeycomb structure having porous partition walls and a plurality of cells which are defined by the partition walls and which extend through the structure from one end surface to the other end surface thereof; a plurality of first plugging members which plug openings of predetermined cells on a side of the one end surface; and a plurality of second plugging members which plug openings of the remaining cells on a side of the other end surface, the columnar honeycomb structure and the plurality of first and second plugging members being fired, wherein the first plugging member on the side of the one end surface includes a convex portion having a shape convex toward the center of the cell in an axial direction on an end portion of the member on a side opposite to the end surface in which the cell to be plugged is opened, and the length of said convex portion in the axial direction from a hem portion thereof to a vertex portion thereof is 0.1 mm or more and less than 3 mm.