A honeycomb filter includes a plugged honeycomb structure body which has cell rows arranged along one direction in a cross section of the honeycomb structure body and including a first cell row constituted of inflow cells and a second cell row including outflow cells. A width P1 (mm) of the first cell row, a width P2 (mm) of the second cell row and a curvature radius R (m) of a curved shape of corner portions of a polygonal shape of each cell satisfy relations of Equations (1) and (2) below: Equation (1): 2100(P1/P2100)50, and Equation (2): 0.4(R/1000)/((P1+P2)/2)10020.

A honeycomb structure includes a plurality of prismatic columnar shaped honeycomb segments; a bonding layer bonding side faces of the honeycomb segments; and a circumferential wall disposed to surround a honeycomb segment bonded body having the honeycomb segments arranged in a grid pattern and bonded with the bonding layer, wherein the honeycomb segments has a porous partition wall disposed to surround a plurality of cells, the cells in other than outermost circumference have a hexagonal shape in a section orthogonal to the cell extending direction, the honeycomb segments include first and second honeycomb segment, the second honeycomb segment is different from the first in at least one of: a shape in the section; a size; and an arrangement direction of the cells and an extended line of one diagonal line imaginarily depicted in the cells in the first honeycomb segment and that in the second are configured to be orthogonal.

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 plugged honeycomb structure includes a honeycomb structure body, and a plurality of plugging portions, the honeycomb structure body further includes pass-through hole portions each of which is formed in at least a part of a partition wall intersection portion in which the partition walls intersect in one end face and each of which interconnects a pair of cells facing each other at a position corresponding to the partition wall intersection portion to enable pass-through of a fluid, and a value obtained by dividing a diameter of a first virtual inscribed circle inscribed at a position of a minimum hole width of the pass-through hole portion by a diameter of a second virtual inscribed circle inscribed at a position of a minimum plugging width between the plugging portions facing each other is in a range of 0.05 to 0.74.

The invention relates to a wall-flow filter for cleaning exhaust gases from engines, with parallel exhaust gas inlet channels and exhaust gas outlet channels which are closed at alternate ends, said filter additionally comprising catalyst channels which are closed at both ends and contain a catalyst in solid form. The invention also relates to production methods and uses of the filter for cleaning exhaust gases, particularly from diesel engines.

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%.

The invention relates to a wall-flow filter for cleaning exhaust gases from engines, with parallel exhaust gas inlet channels and exhaust gas outlet channels which are closed at alternate ends, said filter additionally comprising catalyst channels which are closed at both ends and contain a catalyst in solid form. The invention also relates to production methods and uses of the filter for cleaning exhaust gases, particularly from diesel engines.

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.

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.