Provided is an exhaust gas purification catalyst body that can improve exhaust gas purification performance while maintaining favorable PM collection performance. The exhaust gas purification catalyst body includes a base of a wall flow structure having an inlet side cell, an outlet side cell, and porous partition wall, and a catalyst layer that is formed in the partition wall that is in contact with the inlet side cell or the outlet side cell. The catalyst layer is formed in a region of at least 50% of the thickness of the partition wall from a surface of the partition wall, and held on the surface of internal pores in the partition wall in the region.

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.

A ceramic porous body comprising: skeleton portions; and pore portions formed between the skeleton portions, the pore portions being capable of allowing a fluid to flow therethrough. In the ceramic porous body, the pore portions satisfy the following equations (1) and (2) in a cross section parallel to a flow direction of the fluid;
L1/L2≥0.92  (1), and
L1+L2≤27 μm  (2) in which L1 is an average length of the pore portions in the flow direction of the fluid; and L2 is an average length of the pore portions in a direction orthogonal to the flow direction of the fluid.

Provided is an exhaust gas purification catalyst body that can improve exhaust gas purification performance while maintaining favorable PM collection performance. The exhaust gas purification catalyst body includes a base of a wall flow structure having an inlet side cell, an outlet side cell, and porous partition wall, and a catalyst layer that is formed in the partition wall that is in contact with the inlet side cell or the outlet side cell. The catalyst layer is formed in a region of at least 50% of the thickness of the partition wall from a surface of the partition wall, and held on the surface of internal pores in the partition wall in the region.

A honeycomb body having intersecting porous walls which includes first through fourth cells, wherein the cells extend from inlet to outlet face and are plugged to define a repeating structural unit with three inlets and one outlet channel. Repeating structural unit includes a first channel including length L.sub.1, width W.sub.2, and area A.sub.1, a second channel including length L.sub.2, the width W.sub.2, and area A.sub.2, a third channel including the length L.sub.1, width W.sub.1, and area A.sub.3, and a fourth channel including the length L.sub.2, the width W.sub.1, and A.sub.4, wherein the first through third channels are inlets and the fourth channel is a rectangular outlet and at least one of W.sub.1>W.sub.2 and L.sub.1L.sub.2, i.e. W.sub.1>W.sub.2, or L.sub.1L.sub.2, or W.sub.1>W.sub.2 and L.sub.1L.sub.2. Repeating structural unit has a quadrilateral outer perimeter. Particulate filters including the honeycomb body, honeycomb extrusion dies, and methods of manufacturing the honeycomb body are provided.

A porous composite includes a porous base material and a porous collection layer formed on the base material. The collection layer has a thickness greater than or equal to 6 m. The collection layer has a plurality of large pores, each exposing the surface of the base material. A sum of areas of exposed regions of the base material that are each exposed from each large pore of the plurality of large pores is greater than or equal to 1% of the total area of the collection layer and less than or equal to 30% thereof. This allows the porous composite to achieve a favorable efficiency of collecting particulate matter and to increase the accessible area between the particulate matter and the collection layer and thereby accelerate oxidation of the particulate matter collected by the porous composite.

An exhaust gas purification filter includes a plurality of cells each extending from an inflow end face to an outflow end face, a porous partition wall forming the cells in a partitioned manner, inflow-side sealing parts sealing openings on an inflow end face side of outflow cells where the exhaust gas flows out, and outflow-side sealing parts sealing openings on an outflow end face side of inflow cells where the exhaust gas flows in. Each of the inflow-side sealing parts has a porosity of less than 60%. The partition wall has a porosity of 60% or more and 70% or less. Assuming a pore size, at which cumulative pore volume is 50% in pore size distribution of the inflow-side sealing parts, is d50.sub.Pin, and a pore size, at which cumulative pore volume is 50% in pore size distribution of the partition wall, is d50.sub.B, the pore size d50.sub.Pin is less than 18 m, and the pore size d50.sub.B is 18 m or more and 25 m or less.

An exhaust gas purification filter includes a plurality of cells extending in a filter axial direction, a porous partition separating and defining the plurality of cells, and a sealing section sealing the plurality of cells alternately at both filter ends. The partition has a void volume of a reduced dale, Vvv, and a material volume of a reduced peak, Vmp, as volume parameters determined in noncontact surface roughness measurement on a surface of the partition, with their total value being more than 1.3 m.sup.3/m.sup.2 and 1.7 m.sup.3/m.sup.2 or less. The partition has a mean pore size of 12 m or more and 20 m or less. The partition also has a porosity of 50% or more and 75% or less.

A honeycomb body (100) having a porous ceramic honeycomb structure with a first end (105), a second end (135), and a plurality of walls (115) having wall surfaces defining a plurality of inner channels (110). A porous material is disposed on one or more of the wall surfaces of the honeycomb body (100). A method for forming a honeycomb body (100) includes depositing a porous inorganic material on a ceramic honeycomb body (100) and binding the porous inorganic material to the ceramic honeycomb body (100) to form the porous layer.

A silicon carbide ceramic honeycomb structure having large numbers of axially penetrating flow paths partitioned by porous silicon carbide cell walls, the cell walls comprising silicon carbide particles as aggregate and binder layers for binding the silicon carbide particles, the binder layers having at least a cordierite phase and a spinel phase, and the molar ratio M1 of the cordierite phase [=cordierite phase/(cordierite phase+spinel phase)] being 0.4-0.9.