Exhaust gas purification filter

摘要

An exhaust gas purification filter comprising a metal porous body obtained by packing and fixing metal fibers having a mean fiber diameter of 5 to 40 mu m or heat resistant ceramic fibers having a mean fiber diameter of 1 to 40 mu m in a dispersed state into pores of a foamed structure porous body made of a heat-resistant metal so that a packing density of the resulting metal porous body is from 5 to 20%. The filter may be in a laminated structure by laminating the foregoing foamed structure porous body filled with or without the metal or ceramic fibers and a fiber structure porous body obtained by fixing metal fibers having a mean diameter of 5 to 40 mu m or heat-resistant ceramic fibers having a mean diameter of 1 to 40 mu m in a dispersed state so that a packing density is from 5 to 25% are laminated. By using the inventive filter for collecting PM (dry soot, fine particles and SOF) contained in an exhaust gas of a Diesel engine, a pressure loss for the exhaust gas is minimized while high collection efficiency is kept.