| 摘要 |
<p>PURPOSE:To obtain a filter for purifying an exhaust gas having high collecting capacity and low pressure loss, by a method wherein the outer shape of a filter is formed into a pillar form while each hole is formed into an oval shape and the long diameter thereof is oriented vertically against a gas discharge direction. CONSTITUTION:As a filter for purifying an exhaust gas from the internal combustion engine of an automobile, a base material 1 comprising a foamed org. high molecular substance such as polyurethane foam is formed into a pillar shape and, after the pillar shaped base material is inserted into a metal net 2, it is compressed by a disc 3 and the hole A of the base material 1 is deformed into an oval shape and, after directly immersed in a slurry of silica or alumina, the impregnated base material is baked and dried to coat the pore wall. The long diameter of the hole of thus obtained filter 1 is oriented vertically against a exhaust gas passing direction. This filter has high collecting capacity and pressure loss thereof is low.</p> |
