A honeycomb filter includes a pillar-shaped honeycomb structure body having a porous partition wall disposed to surround a plurality of cells and a plugging portion provided at an open end on a first end face side or a second end face side of each of the cells, wherein the partition wall is composed of a material containing cordierite as a main component thereof, a number per unit area of pores which exist at a surface of the partition wall and which have equivalent circle diameters exceeding 3.0 μm is 1400 per mm.sup.2 or more, and, in a pore diameter distribution which indicates a cumulative pore volume of the partition wall, with a log pore diameter on a horizontal axis and a log differential pore volume (cm.sup.3/g) on a vertical axis, a half-value width of a first peak that includes a maximum value of the log differential pore volume is 0.30 or less.

A honeycomb filter includes a pillar-shaped honeycomb structure body having a porous partition wall disposed to surround a plurality of cells and a plugging portion provided at an open end on a first end face side or a second end face side of each of the cells, wherein the partition wall is composed of a material containing cordierite as a main component thereof, a number per unit area of pores which exist at a surface of the partition wall and which have equivalent circle diameters exceeding 3.0 μm is 1400 per mm.sup.2 or more, and, in a pore diameter distribution which indicates a cumulative pore volume of the partition wall, with a log pore diameter on a horizontal axis and a log differential pore volume (cm.sup.3/g) on a vertical axis, a half-value width of a first peak that includes a maximum value of the log differential pore volume is 0.30 or less.

A method of plugging a filter, comprising: positioning a mask layer over the filter comprising a plurality of intersecting walls, wherein the intersecting walls define at least one channel between the intersecting walls; perforating the mask layer proximate the channel to form a hole, wherein the hole extends around a portion of a perimeter of the channel such that the mask layer defines a flap extending over a center of the channel; passing a plugging mixture into the channel through the hole in the mask layer; and sintering the plugging mixture to form a plug within the channel.

A method of plugging a filter, comprising: positioning a mask layer over the filter comprising a plurality of intersecting walls, wherein the intersecting walls define at least one channel between the intersecting walls; perforating the mask layer proximate the channel to form a hole, wherein the hole extends around a portion of a perimeter of the channel such that the mask layer defines a flap extending over a center of the channel; passing a plugging mixture into the channel through the hole in the mask layer; and sintering the plugging mixture to form a plug within the channel.

In a method of making a gaseous emissions treatment component, a ‘green’ ceramic mix is extruded through a die to form an extrusion having cells extending along the extrusion, the cells being bounded by walls dividing adjacent cells from one another. In concert with the extruding, metal is fed through the die with the extruded mix. A length of the extrusion and associated metal is then cut off and fired to form the component.

Methods of manufacturing a ceramic honeycomb body having a honeycomb structure with a matrix of intersecting walls, and a skin disposed on an outer peripheral portion of the matrix where the skin has a first average porosity and the interior portion of the matrix has a second average porosity that is greater than the first average porosity. The methods include coating at least the skin with a fluid formulation containing a sintering aid and subsequently firing the honeycomb structure. In certain embodiments, a glass layer is formed in the skin or in regions of the walls directly adjacent to the skin. In certain embodiments, the coating is applied to a green honeycomb structure, and in other embodiments the coating is applied to a ceramic honeycomb structure. Other honeycomb bodies and methods are described.

Methods of manufacturing a ceramic honeycomb body having a honeycomb structure with a matrix of intersecting walls, and a skin disposed on an outer peripheral portion of the matrix where the skin has a first average porosity and the interior portion of the matrix has a second average porosity that is greater than the first average porosity. The methods include coating at least the skin with a fluid formulation containing a sintering aid and subsequently firing the honeycomb structure. In certain embodiments, a glass layer is formed in the skin or in regions of the walls directly adjacent to the skin. In certain embodiments, the coating is applied to a green honeycomb structure, and in other embodiments the coating is applied to a ceramic honeycomb structure. Other honeycomb bodies and methods are described.

A ceramic honeycomb body having a skin that does not block partial cells extending from an inlet face to an outlet face at an outer periphery portion of the body. A method of making the ceramic honeycomb body having the skin includes disposing a sheet on an outer peripheral wall of a honeycomb core having an outer surface spaced apart from interiors of the partial cells and skinning the body having the sheet disposed thereon. Subsequent curing in the method bonds the skin to cell walls of the body spaced apart from interiors of the partial cells.

A ceramic honeycomb body having a skin that does not block partial cells extending from an inlet face to an outlet face at an outer periphery portion of the body. A method of making the ceramic honeycomb body having the skin includes disposing a sheet on an outer peripheral wall of a honeycomb core having an outer surface spaced apart from interiors of the partial cells and skinning the body having the sheet disposed thereon. Subsequent curing in the method bonds the skin to cell walls of the body spaced apart from interiors of the partial cells.

A plugged honeycomb structure, including: a pillar-shaped honeycomb structure body including porous partition walls; and plugging portions disposed at open ends of cells at an inflow end face side or at an outflow end face side, wherein a pore diameter corresponding to the cumulative pore volume of 10% is D10, a pore diameter corresponding to the cumulative pore volume of 30% is D30, a pore diameter corresponding to the cumulative pore volume of 50% is D50, a pore diameter corresponding to the cumulative pore volume of 70% is D70, a pore diameter corresponding to the cumulative pore volume of 90% is D90, the pore diameter D10 is 6 μm or more, the pore diameter D90 is 58 μm or less, and the plugged honeycomb structure satisfies the relationship of Expression (1).
0.35≤(D70−D30)/D50≤1.5  Expression (1):