Ceramic honeycomb filter

摘要

A ceramic honeycomb filter comprising a ceramic honeycomb structure having porous partition walls defining a plurality of flow paths for flowing an exhaust gas through the porous partition walls to remove particulates from the exhaust gas, the predetermined flow paths among the flow paths being sealed at their ends, a catalyst being carried by the porous partition walls, the porous partition walls having a porosity of 60-75% and an average pore diameter of 15-25 mu m when measured according to a mercury penetration method, and the maximum of a slope Sn of a cumulative pore volume curve of the porous partition walls relative to a pore diameter obtained at an n-th measurement point being 0.7 or more, the Sn being represented by the following formula (1): Sn = - (Vn- Vn-1)/Älog Dn - log (Dn-1)Ü wherein Dn is a pore diameter ( mu m) at an n-th measurement point, Dn-1 is a pore diameter ( mu m) at an (n-1)-th measurement point, Vn is a cumulative pore volume (cm<3>/g) at an n-th measurement point, and Vn-1 is a cumulative pore volume (cm<3>/g) at an (n-1)-th measurement point.