| 摘要 |
Disclosed is a ceramic honeycomb filter which comprises a ceramic honeycomb structure having multiple flow paths partitioned by porous partition walls, and sealing portions alternately provided on the exhaust gas inflow sides or exhaust gas outflow sides of the flow paths, and removes fine particles contained in exhaust gas by passing the exhaust gas through the porous partition walls. Said ceramic honeycomb filter is characterized in that the porosity of the porous partition walls is 45-75%, the median pore size (A) (µm) of the partition walls measured by a mercury intrusion method and the median pore size (B) (µm) of the partition walls measured by a bubble point method satisfy an expression: 35<(A-B)/B×100=70, the maximum pore size of the partition walls measured by the bubble point method is 100 µm or less, the bulk filter density is 0.5 g/cm3 or less, the thermal expansion coefficient in the range of 20-800°C is 13×10-7/°C or less, and the gas permeability of the porous partition walls is 2-10×10-12 m2. |
