US 12,390,756 B2
Honeycomb filter
Fumihiko Yoshioka, Nagoya (JP); and Sachiko Ishida, Nagoya (JP)
Assigned to NGK INSULATORS, LTD., Nagoya (JP)
Filed by NGK Insulators, Ltd., Nagoya (JP)
Filed on Dec. 22, 2021, as Appl. No. 17/645,466.
Claims priority of application No. 2021-055958 (JP), filed on Mar. 29, 2021.
Prior Publication US 2022/0305422 A1, Sep. 29, 2022
Int. Cl. B01D 46/24 (2006.01); B01D 53/94 (2006.01); B01J 21/04 (2006.01); B01J 23/44 (2006.01); B01J 35/31 (2024.01); B01J 35/56 (2024.01); B01J 35/64 (2024.01); F01N 3/28 (2006.01)
CPC B01D 46/24492 (2021.08) [B01D 46/24491 (2021.08); B01D 46/2482 (2021.08); B01D 46/2484 (2021.08); B01D 53/94 (2013.01); B01J 21/04 (2013.01); B01J 23/44 (2013.01); B01J 35/31 (2024.01); B01J 35/56 (2024.01); B01J 35/657 (2024.01); B01D 2255/1023 (2013.01); B01D 2255/2065 (2013.01); B01D 2255/20715 (2013.01); B01D 2255/2092 (2013.01); B01D 2255/9155 (2013.01); B01D 2279/30 (2013.01); F01N 3/2803 (2013.01); F01N 2330/30 (2013.01); F01N 2370/02 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A honeycomb filter comprising: a honeycomb structure having a porous partition wall disposed so as to surround a plurality of cells serving as a fluid through channel extending from an inflow end face to an outflow end face; and a plugging portion provided so as to plug end at any one of the inflow end face side or the outflow end face side of the cell, wherein
the cells having the plugging portion at ends on the outflow end face side and that are open on the inflow end face side are inflow cells,
the cells having the plugging portion at ends on the inflow end face side and that are open on the outflow end face side are outflow cells,
the honeycomb structure has an inflow side region that is at least 30% with respect to the total length of the honeycomb structure with the inflow end face of the honeycomb structure as the starting point and an outflow side region that is at least 20% with respect to the total length of the honeycomb structure with the outflow end face of the honeycomb structure as the starting point, in the extending direction of the cell of the honeycomb structure,
the honeycomb structure has an intermediate region between the inflow side region and the outflow side region in the extending direction of the cell,
an average pore diameter of the partition wall in the inflow side region is 15 to 20 μm and an average pore diameter of the partition wall in the outflow side region is 9 to 14 μm, and
an average pore diameter of the partition wall in the intermediate region has a range that is neither in the range of 15 to 20 μm of average pore diameter of the partition wall in the inflow side region, nor in the range of 9 to 14 μm of the average pore diameter of the partition wall in the outflow side region.