| abstract |
An open end surface of a first cell 2a becoming an inflow cell 2 is larger than that of a second cell 2b becoming an outflow cell 2 on a partition wall 1 thus arranged in that it surrounds at least a first cell 2a, opposite parts having a first cell 2a interposed therebetween are respectively provided with a first projection 6a and a second projection 6b projecting into the first cell 2a, the first projection 6a and the second protrusion 6b are each arranged to at least partially overlap each other on extension lines in extension directions of the respective protrusions 6a and 6b, and an intermediate protrusion length X of a distal end of the first protrusion 6a and a distal end of the second protrusion 6b is equal to or greater than 10% and equal to or less than 70% with respect to egg nen mutual distance W of the partitions 1, which are opposite to each other. |