Honeycomb filter

A honeycomb filter comprising:

• a pillar-shaped honeycomb structure having a plurality of porous partition walls disposed to surround a plurality of cells which serve as fluid through channels extending from an inflow end face to an outflow end face;
• and
• a plurality of plugging portions disposed at an open end of predetermined cells of the plurality of cells on the inflow end face and at an open end of residual cells of the plurality of cells on the outflow end face;
• wherein
• a porosity of the plurality of plugging portions is 40 to 60%,
• a central plugging portion having a plugging length L in an extending direction of the plurality of cells of 5 mm or more is disposed at a center part side of an end on the inflow end face or an end on the outflow end face of the honeycomb structure, and an outer peripheral plugging portion having the plugging length L of less than 5 mm is disposed at an outer peripheral part side outside the center part of the end on the inflow end face or the end on the outflow end face of the honeycomb structure,
• an average plugging length L1(Ave), which is an average value of the plugging length L in the center part side, is 5 mm or more and 10 mm or less,
• an average plugging length L2(Ave), which is an average value of the plugging length L in the outer peripheral part side, is 2 mm or more and less than 5 mm,
• a difference ΔL between the average plugging length L1(Ave) in the center part side and the average plugging length L2(Ave) in the outer peripheral part side is 2 to 6 mm,
• a ratio (R/D) of an average radius R of the center part side to an equivalent circle radius D of the inflow end face or the outflow end face of the honeycomb structure is 0.2 to 0.38, and
• in an electron microscope image of the plurality of plugging portions, each plugging portion of the plurality of plugging portions is composed of a plurality of particles, an average value of an equivalent circle diameter of each particle is 3 to 5 μm, and a particle density of each plugging portion of the plurality of plugging portions is 750 to 1250 particles/mm2.