| 摘要 |
PROBLEM TO BE SOLVED: To improve durability by preventing occurrence of cracks in a filtering material even if the filtering material is exposed to high temperature due to combustion heat of collected fine particles, and to regenerate a filtering surface to deposition of exhaust gas fine particles in a wall flow type filter. SOLUTION: A ceramic fiber sheet is used to absorb thermal expansion caused by exposure of the interior of a honeycomb structure to high temperature, whereby the occurrence of cracks of the filtering material is prevented. A heat insulation space is provided in a part of the filtering material to naturally oxidize the exhaust gas fine particles, and an oxidization catalyst for fine particles can be jointly used. |
