Patent ID: 8556615

Claim:
A die for forming a honeycomb structure, comprising: in one end face of a plate-like die base member, a clay supply face provided with a plurality of introduction holes through which a clay made of a ceramic forming material is introduced; and in the other end face of the die base member, a clay forming face provided with lattice-like slits having been connected to the introduction holes in the die base member, and through which the clay is extruded to form a formed honeycomb article, at least a part of a plurality of lattice-like partition regions defined by the slits in the clay forming face being provided in such a position that the extended line of said at least part of a plurality of lattice-like regions overlap with the slits at the edges thereof in a plane seen from a thickness direction of the die base member, the slits including an inner peripheral slit formed in an inner peripheral region of the clay forming face and having a slit width set to a predetermined width, and an outer peripheral slit formed in an outer peripheral region which surrounds the periphery of the inner peripheral region of the clay forming face and having a width-enlarged portion in the slit which has a width larger than that of the inner peripheral slit, wherein the width of the width-enlarged portion of the outer peripheral slit becomes narrow so as to be equal to the predetermined width of the slit in the inner peripheral region at the end of the width-enlarged portion on the side of the clay supply face, and a reaching depth of the end of the formed slit having a width-enlarged portion gradually increases, starting from the boundary between the inner peripheral region and the outer peripheral region toward the outer peripheral side of the die base member.