| 摘要 |
<p>There is provided a honeycomb filter (1) wherein particles having an average particle diameter smaller than the average pore diameter of partition walls (4) are deposited at least in open pores formed in the surface layer of the partition wall (4) and in the pores of the partition wall in a surface layer portion (4a) of the partition walls on the exhaust gas inflow side, thereby forming a composite region. The average pore diameter of the partition walls is 5 to 40 µm, and the porosity of the partition wall is 35 to 75%. The particles to be deposited have an average particle diameter of 1 to 15 µm, and the height of the composite region is not more than 80 µm in the direction from the outermost contour line of the partition walls to the surface of the partition walls. The honeycomb filter (1) can be reduced in the pressure loss of the partition wall when an exhaust gas passes through the partition walls at a high flow rate, while obtaining the same effects that would be provided by a layer formed on the partition wall. The honeycomb filter has improved regeneration efficiency, while achieving improved purifying performance. In addition, the honeycomb filter has improved collecting efficiency, while achieving reduced pressure loss after soot deposition. Furthermore, the honeycomb filter is also reduced in the pressure loss after ash deposition.</p> |
