A method for forming a plugged honeycomb article includes feeding a ceramic precursor material through an extrusion die, the extrusion die having a plurality of pins, a plurality of cavities bounded by adjacent pins, and alternating end-faces of the plurality of pins include extensions extending from an outlet of the extrusion die in an extrusion direction. The method further includes extruding the ceramic precursor material through the extrusion die to form a web structure comprising a plurality of cell walls and channels bounded by adjacent cell walls, supporting the web structure that has been extruded through the extrusion die, and providing movement between the extrusion die and the web structure in at least one direction substantially orthogonal to the extrusion direction while the extensions are positioned in at least a portion of the channels.

An exhaust gas purification filter has a honeycomb structure body and upstream side plug members. Cell holes are composed of inlet cell holes and outlet cell holes. In a central area and an outer peripheral area, a gas flow channel cross sectional area Sc1 of the outlet cell holes is larger than a gas flow channel cross sectional area So1 of the inlet cell holes, where Sc1<So1. A first ratio Rc is smaller than a second ratio Ro. The first ratio Rc is a ratio of Sc1 and Sc2. The second ratio Ro is a ratio of So1 to So2. In a first direction X and a second direction Y, the inlet cell holes and the outlet cell holes are alternately arranged, and the cell walls in the central area are larger in thickness than the cell walls in the outer peripheral area.

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.

A honeycomb filter includes a pillar-shaped honeycomb substrate and a plugging portion provided at an end portion on either an inflow or outflow end face side of cells, wherein, in a section orthogonal to the cell extending direction, the shapes of an inflow cell having the plugging portion and an outflow cell having the plugging portion are hexagonal. In the plurality of cells, a plurality of inflow cells surround one outflow cell such that one side of the inflow cell and one side of the outflow cell adjacent to the inflow cell are parallel. The partition wall includes a first partition wall and a second partition wall, at least one of the first partition walls is configured such that a ratio of a thickness of the second partition wall to the first partition wall is 1.0 to 2.5, and a total open frontal area is 35% to 95%.

A honeycomb body (300) including a plurality of radially-extending walls (322) intersecting with a plurality of circumferentially-extending walls (324), the plurality of radially-extending walls (322) and the plurality of circumferentially-extending walls (324) form a plurality of circumferential zones (334A, 334B, 334C) of cells (308). The plurality of circumferential zones (334A, 334B, 334C) of cells (308) includes a first zone of cells (334A) including two or more first rings of cells (330) and having a first cell density, and a second zone of cells (334B) including two or more rings of cells (330) having varying cell densities across the two or more rings of cells. Other structures and extrusion dies are disclosed.

A honeycomb structural body includes: a porous cell wall that partitions a cylindrical casing; and a large number of cells extending in the axial direction X thereof and alternately blocked at an upstream end face. The large number of cells include plugged cells having plugs and penetrating cells that do not have the plugs. The plugged cells and the penetrating cells both include complete cells and incomplete cells. At least some of plugged incomplete cells of the incomplete cells have a cross-sectional area smaller than a cross-sectional area of penetrating complete cells, and are configured as blocked cells that are entirely blocked inside in the axial direction.

Provided is a porous honeycomb filter comprising a porous first cell wall that permits exhaust gas to permeate, a second cell wall that permits exhaust gas to permeate than the first cell wall, and a cell that is surrounded by the first cell wall and the second cell wall to form an extending gas flow passage. The second cell wall has a smaller porosity than the first cell wall.

An inorganic membrane filtration article and methods for making the same. The membrane filtration article includes a sintered flow-through ceramic honeycomb with a plurality of partition walls defining a plurality of open channels from an inlet end of the honeycomb to an outlet end of the honeycomb. The honeycomb is formed from a cordierite composition with low-sodium and/or low-potassium content for enhanced filtration performance.

A honeycomb structure body is constituted of a circumferential region including the outermost circumference in a cross section of the honeycomb structure body which is perpendicular to an extending direction of cells, and a central region excluding the circumferential region. The circumferential region includes a specific circumferential region in which pressure loss with soot when an amount of the deposited soot is 4 g/L is higher than the pressure loss with soot of the central region as much as 15% or more and in which an open frontal area of the circumferential region is the same as or larger than an open frontal area of the central region. In the cross section of the honeycomb structure body, a ratio of an area of the specific circumferential region is 5% or more to a total area of the circumferential region and the central region.