A thermal shock resistant and asymmetric honeycomb ceramic wall-flow filter includes an inlet honeycomb ceramic surface and an outlet honeycomb ceramic surface. Inlet channels and outlet channels are provided on both the inlet honeycomb ceramic surface and the outlet honeycomb ceramic surface. The inlet channels are in communication with the outlet channels. Outlet ends of the inlet channels and inlet ends of the outlet channels are sealed. An inner diameter of the inlet channel is greater than that of the outlet channel. A cross-section of the inlet channel is a square, or two adjacent edges are connected by two connecting lines, or two adjacent edges are connected by two connecting lines or a circular arc located between the two connecting lines. The filter has good mechanical properties, low back pressure, and excellent thermal shock resistance.

A particulate trap filter body has asymmetrical channels. The cross-sectional shape of the asymmetrical channel structure includes a combination of hexagonal, square and triangular shapes. The hexagonal channel and the triangular channel act as inlet channel, and the square channel acts as outlet channel. Compared with the traditional symmetrical filter body structure, the inlet channel volume and filter body wall area can be effectively increased by more than 30%, which means that with capturing the same amount of particles, the particle cake layer formed on the wall surface is thinner. The limiting carbon load of the new channel structure is increased by more than 30%, having a very positive effect on reducing the regeneration frequency and prolonging the service life of the trap.

The invention relates to a wall-flow filter, to a method for the production and the use of the filter for reducing harmful exhaust gases of an internal combustion engine. The wall-flow filter was produced by exposing the filter at least twice successively to a powder-gas aerosol.

A honeycomb body for exhaust gas aftertreatment, having a multiplicity of stacked layers. Flow channels are formed between the layers, which extend along the axial extent of the honeycomb body and are flowed through in the axial direction. The honeycomb body has first structured layers formed by successive wave peaks and wave valleys. Protuberances in the direction of the wave peaks belonging to a respective layer are formed from adjacently arranged wave valleys of a first structured layer. The adjacently arranged protuberances of a first structured layer form a channel-like structure extending in the circumferential direction in the first structured layer into which a second layer is inserted to be is fixed in the axial direction with respect to the first structured layer.

A honeycomb filter includes a pillar-shaped honeycomb substrate having a porous partition wall disposed so as to surround a plurality of cells serving as a fluid through channel extending from a first end face to a second end face; and a plugging portion provided at an open end on the first end face side or the second end face side of each of the cells, wherein the partition wall constituting the honeycomb substrate is composed of a ceramic porous material, a ratio of a volume of pores having a pore diameter of 10 μm or less with respect to a total pore volume of the partition wall measured by a mercury press-in method is 85 to 95%, and an average pore diameter of the partition wall measured by the mercury press-in method is 4 to 10 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. The cells include: a plurality of cells A wherein a side of the inflow end face is opened and the outflow end face has a plugged portion; and a plurality of cells B wherein a side of the outflow end face is opened and the inflow end face has a plugged portion, the cells B being arranged alternately with the cells A. One or both of the plugged portion of the cells A and the plugged portions of the cells B contain a magnetic substance and glass.

Ceramic honeycomb bodies and methods for then manufacture are provided. The ceramic honeycomb body comprises a bulk density of less than 210 g/L, a geometric surface area (GSA) greater than 93 in.sup.−1 (3.66 mm.sup.−1), a mechanical integrity factor (MIF) greater than 0.28%, and a back pressure factor (BPF) greater than 0.4 mm.sup.2.

An exhaust gas purification filter includes a cell assembly including cells each having a quadrangular cross-sectional shape and a partition wall, seal members, and a skin member. The partition wall has a porosity P1 of 50% to 70%, and the skin member has a porosity P2 of 50% to 70%, the porosity P1 and the porosity P2 satisfy a relationship P1<P2. A difference between the porosity P2 and the porosity P1 is 20% or less. The partition wall includes crossing portions, each cell has at least one part of an outer periphery defined by a corresponding one of the crossing portions, the at least one part is rounded to have a radius of curvature R, each cell has a radius r of a hydraulic diameter, the radius of curvature R and the radius r of the hydraulic diameter satisfy a relationship 0.2<R [mm]/r [mm]<1.

A plugged honeycomb structure includes intersecting porous walls extending in an axial direction between an inlet end and an outlet end of the honeycomb structure, the intersecting porous walls forming a matrix of repeating unit cells arranged in a repeating pattern. The repeating unit cells comprise: three or four channels, each channel formed by four walls, wherein the three or four channels comprise more inlet channels than outlet channels, at least one wall of an inlet channel or an outlet channel is intersected midwall by a wall, an area of an outlet channel is equal to or less than an area of any of the inlet channels, and continuous line segments extending along walls of at least three repeating unit cells. Other plugged honeycomb structures, plugged honeycomb bodies, honeycomb extrusion dies, and methods are disclosed.

An exhaust gas purification filter includes a cell assembly including cells and a partition wall, seal members, and a skin member. The partition wall has a porosity of 50% to 70%. The skin member has a thickness T of 0.3 mm to 1.0 mm. The partition wall includes crossing portions, each cell has at least one part of an outer periphery defined by a corresponding one of the crossing portions, the at least one part of the outer periphery is rounded to have a value of radius of curvature R being 0.02 mm to 0.6 mm A degree of distortion δ being a degree of change in the external dimensions of the filter in axial direction, is greater than 0 and is 1.5 mm or less. A value of a structural variable X, expressed by Equation 1 below, is 0.05 to 6, X=T×R/δ . . . Equation 1.