A pillar shaped honeycomb structure includes: an outer peripheral wall; and porous partition walls disposed on an inner side of the outer peripheral wall, the partition walls defining a plurality of cells, each of the cells penetrating from one end face to other end face to form a flow path, wherein at least one cell of the cells has a magnetic substance coated with glass.

A particulate filter and method of manufacture. The particulate filter comprises a ceramic honeycomb body comprising a plurality of intersecting walls that define a plurality of channels extending longitudinally though the ceramic honeycomb body. The intersecting walls comprise a porous ceramic material having a microstructure that comprises an interconnected network of porous spheroidal ceramic beads. The microstructure has a total porosity defined as the sum of an open intrabead porosity of the beads and an interbead porosity defined by interstices between the beads in the interconnected network. The microstructure has a bimodal pore size distribution in which an intrabead median pore size of the intrabead porosity is from 1.5 μm to 4 μm and an interbead median pore size of the interbead porosity is from 6 μm to 20 μm.

A ceramic porous body including: skeleton portions including an aggregate and at least one bonding material; and pore portions formed between the skeleton portions, the pore portions being capable of allowing a fluid to flow therethrough, wherein the pore portions have a pore volume ratio of pores having a pore diameter of from 10 to 15 μm, of from 4 to 17%.

A particulate filter having a porous ceramic honeycomb structure with a first end, a second end, and a plurality of walls having wall surfaces defining a plurality of inner channels. Filtration material deposits are disposed on one or more of the wall surfaces of the honeycomb body. The highly porous deposits provide durable high clean filtration efficiency with small impact on pressure drop through the filter.

A honeycomb filter includes a pillar-shaped honeycomb substrate having a porous partition wall and a plugging portion provided so as to plug end at any one of the inflow end face side or the outflow end face side of the cell, wherein in a section orthogonal to the extending direction of the cell, the shape of the cell is hexagonal, the partition wall includes a first partition wall disposed between the inflow cell and the outflow cell and a second partition wall disposed between the inflow cells, and the first partition wall has a porous trapping layer on its surface for trapping particulate matter in exhaust gas, and the second partition wall has no trapping layer on its surface or has a trapping layer thinner than the trapping layer disposed on the surface of the first partition wall.

A pillar-shaped honeycomb structure including an outer peripheral side wall, a plurality of first cells provided on an inner peripheral side of the outer peripheral side wall, the first cells extending from a first end surface to a second end surface, each opening on the first end surface and having a sealing portion with an average void ratio of 4% or less on the second end surface, and a plurality of second cells provided on the inner peripheral side of the outer peripheral side wall, the second cells extending from the first end surface to the second end surface, each having a sealing portion with an average void ratio of 4% or less on the first end surface and opening on the second end surface, the first cells and the second cells being alternately arranged adjacent to each other with a partition wall interposed therebetween.

A honeycomb filter includes a pillar-shaped honeycomb substrate having a porous partition wall and a plugging portion provided so as to plug end at any one of the inflow end face side or the outflow end face side of the cell, wherein in a section orthogonal to the extending direction of the cell, the shape of the cell is hexagonal, the partition wall includes a first partition wall disposed between the inflow cell and the outflow cell and a second partition wall disposed between the inflow cells, and the first partition wall has a porous trapping layer on its surface for trapping particulate matter in exhaust gas, and the second partition wall has no trapping layer on its surface or has a trapping layer thinner than the trapping layer disposed on the surface of the first partition wall.

A pillar shaped honeycomb structure includes: an outer peripheral wall; and porous partition walls disposed on an inner side of the outer peripheral wall, the partition walls defining a plurality of cells, each of the cells extending from one end face to other end face to form a flow path, wherein the cells include a plurality of wire pieces made of a magnetic substance, the wire pieces being provided apart from each other via spaces or buffer materials in an extending direction of the cells.

A honeycomb filter includes a honeycomb structure having a porous partition wall disposed to surround a plurality of cells; and a plugging portion provided at one end of the cell, wherein the honeycomb structure has an inflow side region including a range of up to at least 30% with respect to the total length of the honeycomb structure with the inflow end face as the starting point and an outflow side region including a range of up to at least 20% with respect to the total length of the honeycomb structure with the outflow end face as the starting point, in the extending direction of the cell of the honeycomb structure, an average pore diameter of the partition wall in the inflow side region is 9 to 14 μm and an average pore diameter of the partition wall in the outflow side region is 15 to 20 μm.

A pillar shaped honeycomb structure includes: a porous partition wall that defines a plurality of cells, the cells forming flow paths for a fluid, the cells extending from an inflow end face to an outflow end face; and an outer peripheral wall located at the outermost circumference. At least a part of surfaces of the partition walls has a surface layer, and the surface layer includes magnetic particles and has permeability.