| abstract |
A honeycomb filter capable of collecting fine particles in exhaust gas discharged from an internal combustion engine while suppressing a decrease in catalytic activity. A honeycomb filter 100 is made of porous ceramics containing aluminum titanate, and has a plurality of substantially parallel flow paths 110a, 110b partitioned by a partition wall 112, and flows on one end face 100a. One end of the path is sealed by the sealing part 114, the other end of the flow path is sealed by the sealing part at the other end surface 100b, and the surface of the partition wall in the flow path 110b is made of γ-alumina or its precursor. A catalyst undercoat film 116 containing at least one aluminum component is formed, the coverage of the catalyst undercoat film is 0.5 to 20% by mass based on the total amount of the honeycomb filter, and Na content in the catalyst undercoat film The amount is 100 mass ppm or less based on the total amount of the catalyst undercoat coating film. [Selection] Figure 1 |