Abstract: A honeycomb filter includes a pillar-shaped honeycomb structure having porous partition walls provided, surrounding a plurality of cells which serve as fluid through channels extending from an inflow end face to an outflow end face, and a porous plugging portion provided either at an end on the inflow end face or the outflow end face of the cells, wherein the plugging portion is composed of a porous material, the honeycomb structure has a central region and a circumferential region, and a ratio of an area of the circumferential region with respect to that of the central region ranges from 0.1 to 0.5, porosity of a central plugging portion in the central region is lower than that of a circumferential plugging portion in the circumferential region, and the porosity of the central plugging portions ranges from 60% to 68%, and that of the circumferential plugging portions ranges from 70% to 85%.

Abstract: A honeycomb filter includes a pillar-shaped honeycomb structure body having a porous partition wall disposed to surround a plurality of cells and a plugging portion, wherein the partition wall is composed of a material containing cordierite as a main component thereof, porosity of the partition wall measured by a mercury press-in method is 60 to 68%, an average pore diameter of the partition wall measured by a mercury press-in method is 8 to 12 and in a pore diameter distribution which indicates a cumulative pore volume of the partition wall measured by a mercury press-in method, with a pore diameter (?m) on an abscissa axis and a log differential pore volume (cm3/g) on an ordinate axis, a first peak that includes a maximum value of the log differential pore volume has a pore diameter value of 10 ?m or less, the pore diameter value corresponding to a ? value width of the maximum value.

Abstract: A honeycomb filter includes a pillar-shaped honeycomb structure body having a porous partition wall disposed to surround a plurality of cells and a plugging portion, wherein the partition wall is composed of a material containing cordierite as a main component thereof, porosity of the partition wall measured by a mercury press-in method is 55 to 65%, an average pore diameter of the partition wall measured by a mercury press-in method is 5 to 10 ?m, and in a pore diameter distribution indicating a cumulative pore volume of the partition wall measured by a mercury press-in method, with a pore diameter (?m) on an abscissa axis and a log differential pore volume (cm3/g) on an ordinate axis, a first peak including a maximum value of the log differential pore volume has a pore diameter value of 8 ?m or less, the pore diameter value corresponding to a ? value width of the maximum value.

Abstract: A honeycomb filter includes a pillar-shaped honeycomb structure body having a porous partition wall disposed to surround a plurality of cells and a plugging portion, wherein the partition wall is composed of a material containing cordierite as a main component thereof, porosity of the partition wall measured by a mercury press-in method is 60 to 68%, an average pore diameter of the partition wall measured by a mercury press-in method is 13 to 18 ?m, and in a pore diameter distribution indicating a cumulative pore volume of the partition wall measured by a mercury press-in method, with a pore diameter (?m) on an abscissa axis and a log differential pore volume (cm3/g) on an ordinate axis, a first peak including a maximum value of the log differential pore volume has a pore diameter value of 15 ?m or less, the pore diameter value corresponding to a ? value width of the maximum value.

Abstract: A honeycomb filter includes a pillar-shaped honeycomb structure body having a porous partition wall disposed to surround a plurality of cells and a plugging portion, wherein the partition wall is composed of a material containing cordierite as a main component thereof, porosity of the partition wall measured by a mercury press-in method is 60 to 68%, an average pore diameter of the partition wall measured by a mercury press-in method is 19 to 26 ?m, and in a pore diameter distribution indicating a cumulative pore volume of the partition wall measured by a mercury press-in method, with a pore diameter (?m) on an abscissa axis and a log differential pore volume (cm3/g) on an ordinate axis, a first peak including a maximum value of the log differential pore volume has a pore diameter value of 18 ?m or less, the pore diameter value corresponding to a ? value width of the maximum value.

Abstract: A honeycomb filter includes a pillar-shaped honeycomb structure having porous partition walls provided, surrounding a plurality of cells which serve as fluid through channels extending from an inflow end face to an outflow end face, and porous plugging portions provided either at the ends on the inflow end face or the outflow end face of the cells, wherein the plugging portions are composed of a porous material, the honeycomb structure has a central region and a circumferential region and a ratio of an area of the circumferential region with respect to that of the central region ranges from 0.1 to 0.5, and a plugging length L1 in the cell extending direction of a central plugging portion in the central region is smaller than a plugging length L2 of a circumferential plugging portion in the circumferential region, L1 ranges from 3 to 6 mm, and L2 from 7 to 9 mm.

Abstract: A honeycomb filter includes a pillar-shaped honeycomb structure having porous partition walls placed, surrounding a plurality of cells which serve as fluid through channels extending from an inflow end face to an outflow end face; and porous plugging portions provided either at the ends on the inflow end face side of the cells or at the ends on the outflow end face side of the cells, wherein the plugging portions include plugging portions that have voids therein, and in the plugging portions having the voids, porosity including the voids as pores ranges from 68% to 83%.

Abstract: A honeycomb filter includes a pillar-shaped honeycomb structure having porous partition walls provided, surrounding a plurality of cells which serve as fluid through channels extending from an inflow end face to an outflow end face, and porous plugging portions provided either at the ends on the inflow end face side or the outflow end face side of the cells, wherein the plugging portions are composed of a porous material, the honeycomb structure has a central region and a circumferential region, and a ratio of an area of the circumferential region with respect to that of the central region ranges from 0.1 to 0.5, porosity of a central plugging portion in the central region, is higher than that of a circumferential plugging portion in the circumferential region, and the porosity of the central plugging portion ranges from 76% to 85%, and that of the circumferential plugging portion from 60% to 75%.

Abstract: A honeycomb filter includes a pillar-shaped honeycomb structure body having a porous partition wall surrounding cells each of which has one end plugged by a plugging portion. An open frontal area O (%) of the cells in the honeycomb structure body is 75 to 80%, a porosity P (%) of the partition wall measured by a mercury press-in method is 52 to 58%, an average pore diameter D (?m) of the partition wall measured by the mercury press-in method is 6 to 12 ?m, and a pore volume rate A (%) of pores whose pore diameters are not less than 20 ?m with respect to an overall pore volume of the partition wall is not more than 13.5%.

Abstract: A honeycomb filter includes a pillar-shaped honeycomb structure having porous partition walls provided, surrounding a plurality of cells which serve as fluid through channels extending from an inflow end face to an outflow end face, and a porous plugging portion provided either at an end on the inflow end face or the outflow end face of the cells, wherein the plugging portion is composed of a porous material, the honeycomb structure has a central region and a circumferential region, and a ratio of an area of the circumferential region with respect to that of the central region ranges from 0.1 to 0.5, porosity of a central plugging portion in the central region is lower than that of a circumferential plugging portion in the circumferential region, and the porosity of the central plugging portions ranges from 60% to 68%, and that of the circumferential plugging portions ranges from 70% to 85%.

Abstract: A honeycomb filter includes a pillar-shaped honeycomb structure having porous partition walls placed, surrounding a plurality of cells which serve as fluid through channels extending from an inflow end face to an outflow end face; and porous plugging portions provided either at the ends on the inflow end face side of the cells or at the ends on the outflow end face side of the cells, wherein the plugging portions include plugging portions that have voids therein, and in the plugging portions having the voids, porosity including the voids as pores ranges from 68% to 83%.

Abstract: A honeycomb filter includes a pillar-shaped honeycomb structure having porous partition walls provided, surrounding a plurality of cells which serve as fluid through channels extending from an inflow end face to an outflow end face, and porous plugging portions provided either at the ends on the inflow end face or the outflow end face of the cells, wherein the plugging portions are composed of a porous material, the honeycomb structure has a central region and a circumferential region and a ratio of an area of the circumferential region with respect to that of the central region ranges from 0.1 to 0.5, and a plugging length L1 in the cell extending direction of a central plugging portion in the central region is smaller than a plugging length L2 of a circumferential plugging portion in the circumferential region, L1 ranges from 3 to 6 mm, and L2 from 7 to 9 mm.

Abstract: A honeycomb filter includes a pillar-shaped honeycomb structure having porous partition walls provided, surrounding a plurality of cells which serve as fluid through channels extending from an inflow end face to an outflow end face, and porous plugging portions provided either at the ends on the inflow end face or the outflow end face of the cells, wherein the plugging portions are composed of a porous material, the honeycomb structure has a central region and a circumferential region, and a ratio of an area of the circumferential region with respect to that of the central region ranges from 0.1 to 0.5, a plugging length L1 in the cell extending direction of a central plugging portion in the central region is larger than a plugging length L2 of a circumferential plugging portion in the circumferential region, L1 ranges from 7 to 9 mm, and L2 from 3 to 6 mm.

Abstract: A honeycomb filter includes a pillar-shaped honeycomb structure having porous partition walls provided, surrounding a plurality of cells which serve as fluid through channels extending from an inflow end face to an outflow end face, and porous plugging portions provided either at the ends on the inflow end face side or the outflow end face side of the cells, wherein the plugging portions are composed of a porous material, the honeycomb structure has a central region and a circumferential region, and a ratio of an area of the circumferential region with respect to that of the central region ranges from 0.1 to 0.5, porosity of a central plugging portion in the central region, is higher than that of a circumferential plugging portion in the circumferential region, and the porosity of the central plugging portion ranges from 76% to 85%, and that of the circumferential plugging portion from 60% to 75%.

Abstract: A honeycomb filter, including: a honeycomb structure, wherein the honeycomb structure further includes a platinum group element-containing catalyst layer, the platinum group element-containing catalyst layer is disposed only on a side of an inner surface of the partition walls surrounding the inflow cells, and the platinum group element-containing catalyst layer is disposed in a range of at least up to 35% with respect to an overall length of the cells starting from the inflow end face and is not disposed in a range of at least up to 30% with respect to the overall length of the cells starting from the outflow end face, in an extending direction of the cells of the honeycomb structure.

Abstract: A honeycomb filter, including: a honeycomb structure, wherein the honeycomb structure further includes a platinum group element-containing catalyst layer and a trapping layer, the platinum group element-containing catalyst layer is disposed at least on an entire surface of a side of an inner surface of the partition walls surrounding either one of the inflow cells or the outflow cells, the trapping layer does not contain a platinum group element, and the trapping layer is disposed in a range of at least up to 50% with respect to an overall length of the honeycomb structure starting from the outflow end face and is not disposed in a range of at least up to 40% with respect to the overall length starting from the inflow end face, in an extending direction of the cells of the honeycomb structure.

Abstract: A honeycomb filter includes a pillar-shaped honeycomb substrate including a porous partition wall that defines a plurality of cells extending from an inflow end face to an outflow end face, an inflow side plugging portion disposed at the inflow end face of the honeycomb substrate to plug open ends of outflow cells and an outflow side plugging portion disposed at the outflow end face of the honeycomb substrate to plug open ends of inflow cells other than the outflow cells. The honeycomb substrate includes the partition wall that defines two of the inflow cells by division. An average of the plugging length LIN of the inflow side plugging portions disposed in the outflow cells of the honeycomb substrate is larger than an average of the plugging length LOUT of the outflow side plugging portions disposed in the inflow cells of the honeycomb substrate.

Abstract: A honeycomb filter includes a pillar-shaped honeycomb substrate including a porous partition wall that defines a plurality of cells extending from an inflow end face to an outflow end face, an inflow side plugging portion disposed at the inflow end face of the honeycomb substrate to plug open ends of outflow cells; and an outflow side plugging portion disposed at the outflow end face of the honeycomb substrate to plug open ends of inflow cells other than the outflow cells. The honeycomb substrate includes the partition wall that defines two of the inflow cells by division. An average of the plugging length LOUT of the outflow side plugging portions disposed in the inflow cells of the honeycomb substrate is larger than an average of the plugging length LIN of the inflow side plugging portions disposed in the outflow cells of the honeycomb substrate.

Abstract: A honeycomb filter, including: a honeycomb structure, wherein the honeycomb structure includes a platinum group element-containing catalyst layer, the platinum group element-containing catalyst layer is disposed only on a side of an inner surface of the partition walls surrounding the inflow cells, and the platinum group element-containing catalyst layer is disposed in a range of at least up to 40% with respect to an overall length of the cells starting from the outflow end face and is not disposed in a range of at least up to 30% with respect to the overall length of the cells starting from the inflow end face, in an extending direction of the cells of the honeycomb structure.

Abstract: A honeycomb filter, including: a honeycomb structure, wherein the honeycomb structure includes a platinum group element-containing catalyst layer, the platinum group element-containing catalyst layer is disposed only on a side of an inner surface of the partition walls surrounding the outflow cells, and the platinum group element-containing catalyst layer is disposed in a range of at least up to 35% with respect to an overall length of the cells starting from the outflow end face and is not disposed in a range of at least up to 30% with respect to the overall length of the cells starting from the inflow end face, in an extending direction of the cells of the honeycomb structure.