A molded three-dimensional insulator that is suitable for use in an end cone region of a pollution control device and a method of making the insulator are described. The insulator includes ceramic fibers that have a bulk shrinkage no greater than 10 weight percent. The ceramic fibers can contain alumina and silica and can be microcrystalline, crystalline, or a combination thereof.

A molded three-dimensional insulator that is suitable for use in an end cone region of a pollution control device and a method of making the insulator are described. The insulator includes ceramic fibers that have a bulk shrinkage no greater than 10 weight percent. The ceramic fibers can contain alumina and silica and can be microcrystalline, crystalline, or a combination thereof.

A circumferential coating material to be applied to a circumferential surface of a honeycomb structure made of ceramics formed by extrusion, the circumferential coating material including a ceramic raw material that forms a circumferential coating layer, wherein the ceramic raw material contains: a ceramic mixture of first ceramic particles having particulate shapes, and second ceramic particles having particulate shapes and an average particle diameter different from an average particle diameter of the first ceramic particles; and a fiber material having an elongated strip-like shape, wherein the ceramic mixture has particle size distribution including at least two local maximum values, and the fiber material has an average fiber length ranging from 30 to 100 m in a longitudinal direction.

A circumferential coating material to be applied to a circumferential surface of a honeycomb structure made of ceramics formed by extrusion, the circumferential coating material including a ceramic raw material that forms a circumferential coating layer, wherein the ceramic raw material contains: a ceramic mixture of first ceramic particles having particulate shapes, and second ceramic particles having particulate shapes and an average particle diameter different from an average particle diameter of the first ceramic particles; and a fiber material having an elongated strip-like shape, wherein the ceramic mixture has particle size distribution including at least two local maximum values, and the fiber material has an average fiber length ranging from 30 to 100 m in a longitudinal direction.

A method for producing a porous body, comprising a raw-material mixing step of mixing talc having an average particle size of 1 m or more and 18 m or less, alumina, an auxiliary raw material containing a material that undergoes a eutectic reaction with talc and being prepared in an amount so as to satisfy a weight ratio of 0.5% or more and 1.5% or less by weight relative to the talc, and a pore-forming agent, to provide green body, and a molding and firing step of molding the green body to provide a compact and firing this compact at a firing temperature of 1350 C. to 1440 C.

A method for producing a porous body, comprising a raw-material mixing step of mixing talc having an average particle size of 1 m or more and 18 m or less, alumina, an auxiliary raw material containing a material that undergoes a eutectic reaction with talc and being prepared in an amount so as to satisfy a weight ratio of 0.5% or more and 1.5% or less by weight relative to the talc, and a pore-forming agent, to provide green body, and a molding and firing step of molding the green body to provide a compact and firing this compact at a firing temperature of 1350 C. to 1440 C.

A molded three-dimensional insulator that is suitable for use in an end cone region of a pollution control device and a method of making the insulator are described. The insulator includes ceramic fibers that have a bulk shrinkage no greater than 10 weight percent. The ceramic fibers can contain alumina and silica and can be microcrystalline, crystalline, or a combination thereof.

A molded three-dimensional insulator that is suitable for use in an end cone region of a pollution control device and a method of making the insulator are described. The insulator includes ceramic fibers that have a bulk shrinkage no greater than 10 weight percent. The ceramic fibers can contain alumina and silica and can be microcrystalline, crystalline, or a combination thereof.

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.