Pillar-shaped honeycomb structure and method for manufacturing same

A method for manufacturing a pillar-shaped honeycomb structure, the pillar-shaped honeycomb structure comprising an outer peripheral side wall;

• a plurality of first cells disposed on an inner peripheral side of the outer peripheral side wall, each extending from a first end surface to a second end surface, having an opening on the first end surface and having a sealing portion on the second end surface;
• and a plurality of second cells disposed on the inner peripheral side of the outer peripheral side wall, each extending from the first end surface to the second end surface, having a sealing portion on the first end surface, and having an opening on the second end surface;
• the first cells and the second cells being arranged alternately adjacent to each other with partition walls interposed therebetween;
• the method comprising:
• kneading a raw material composition containing a cordierite-forming raw material, a dispersion medium, a pore-forming material, a binder, and further containing one or more sintering aids selected from ceria, zirconia, and titania to form a green body, and then extrusion molding the green body to obtain a pillar-shaped honeycomb formed body comprising an outer peripheral side wall;
• and a plurality of cells disposed on an inner peripheral side of the outer peripheral side wall, each extending from the first end surface to the second end surface and having an opening on both the first end surface and the second end surface;
• drying the pillar-shaped honeycomb formed body, and then filling the openings on the first end surface and the second end surface where the sealing portions are to be formed with a slurry for forming the sealing portions, the slurry for forming the sealing portions containing a cordierite-forming raw material, a dispersion medium, a pore-forming material, a binder, and further containing one or more sintering aids selected from ceria, zirconia, and titania;
• and
• firing the pillar-shaped honeycomb formed body filled with the slurry for forming the sealing portions;
• wherein for the sintering aid in the raw material composition, assuming a total added amount with respect to 100 parts by mass of the cordierite-forming raw material is C1 parts by mass, and for the sintering aid in the slurry for forming the sealing portions, assuming a total added amount with respect to 100 parts by mass of the cordierite-forming raw material is C2 parts by mass, −8≤C1−C2≤1 is satisfied.