A honeycomb body having intersecting porous walls and repeating structural units. Each repeating structural unit has a plurality of inlet channels and outlet channels that extend parallel to each other in an axial direction from an inlet face to an outlet face. Each of the repeating structural units has 2.0<I/O<3.0, wherein I/O is a ratio of a number of inlet channels to a number of the outlet channels, each of the inlet and outlet channels have a same cross-sectional size and shape, and each inlet channel of a particular repeating structural unit directly abuts an outlet channel of the particular repeating structural unit or an outlet channel of an adjacent repeating structural unit. Particulate filters including the honeycomb body, honeycomb extrusion dies, and methods of capturing soot in the honeycomb body are provided, as are other aspects.

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 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 method and extrusion die to form a laminar integral skin of a honeycomb structure is provided. The method includes extruding a ceramic precursor batch through a die with feedholes in entry side and slots in exit face of the die to form the honeycomb structure. In a region on the periphery of the die configured to form the cell matrix, a series of concentric slots around the matrix in the exit face of the die are configured to feed skin onto the matrix. Ring sections between concentric slots are angled away from the center and a mask is disposed on top of the periphery producing a channel for extruded skin to meet and bond to extruded matrix. Optionally, slots in the skin-forming ring sections enhance knitting between laminar skin layers.

A honeycomb structure has partition walls defining a plurality of hexagonal cells the partition walls are constituted by combining standard partition walls having a partition wall thickness in a range smaller than ±10% to an average partition wall thickness of the partition walls, wide partition walls having a partition wall thickness of +10% or more to the average partition wall thickness, and narrow partition walls having a partition wall thickness of −10% or less to the average partition wall thickness, and a non-standard partition wall ratio is in a range of 10% to 30% which is a ratio occupied by a subtotal number of non-standard partition walls obtained by adding the wide partition walls and the narrow partition walls in a total number of the partition walls which is obtained by adding the numbers of the standard partition walls, the wide partition walls and the narrow partition walls.

The honeycomb filter of the present invention comprises a ceramic honeycomb substrate formed from a porous body of sintered ceramic particles, and a filter layer formed on the surface of the cell walls, wherein a portion of the filter layer penetrates from the surface of the cell walls into pores formed by the ceramic particles to form inter-particle filtration bodies, these inter-particle filtration bodies are formed from a plurality of spherical ceramic particles and crosslinking bodies which bind the spherical ceramic particles to each other, and the spherical ceramic particles and the crosslinking bodies form a three-dimensional network structure.

A honeycomb structure includes a pillar-shaped honeycomb structure body including porous partition walls defining and forming a plurality of cells which extend from an inflow end face to an outflow end face, and a porous outer wall surrounding the partition walls, a porous supporting bulge disposed to extend out from a circumference of the outer wall so that at least a part of the outer wall is exposed, and plugging portions arranged in open ends of the cells, and the supporting bulge has support portions and a side wall portion, and the partition walls and the outer wall of the honeycomb structure body and the support portions and the side wall portion of the supporting bulge are all formed monolithically by formation of a ceramic raw material.

In a honeycomb structure, porous partition walls are arranged to surround cells extending from an inflow end face of the honeycomb structure body to an outflow end face thereof, intersection points at which the partition walls arranged in a latticed manner in the inflow end face intersect include a first intersection point that is one intersection point, and second intersection points one of which is the other intersection point in the partition wall including the first intersection point, and which are adjacent to the first intersection point, and the inflow end face has concave/convex portions each including the first intersection point as a bottom portion and the peripheral second intersection points of the first intersection point as top portions, or each including the first intersection point as a top portion and the peripheral second intersection points of the first intersection point as bottom portions.

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 L.sub.IN of the inflow side plugging portions disposed in the outflow cells of the honeycomb substrate is larger than an average of the plugging length L.sub.OUT of the outflow side plugging portions disposed in the inflow cells of the honeycomb substrate.

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 L.sub.OUT of the outflow side plugging portions disposed in the inflow cells of the honeycomb substrate is larger than an average of the plugging length L.sub.IN of the inflow side plugging portions disposed in the outflow cells of the honeycomb substrate.