US 12,239,968 B2
Particulate filter
Ryota Onoe, Kakegawa (JP); Ryo Tasaki, Kakegawa (JP); Momoko Iwai, Kakegawa (JP); and Yamato Matsushita, Kakegawa (JP)
Assigned to CATALER CORPORATION, Kakegawa (JP)
Appl. No. 17/440,817
Filed by CATALER CORPORATION, Kakegawa (JP)
PCT Filed Jun. 1, 2020, PCT No. PCT/JP2020/021608
§ 371(c)(1), (2) Date Sep. 20, 2021,
PCT Pub. No. WO2020/255687, PCT Pub. Date Dec. 24, 2020.
Claims priority of application No. 2019-112755 (JP), filed on Jun. 18, 2019.
Prior Publication US 2022/0184591 A1, Jun. 16, 2022
Int. Cl. B01J 35/56 (2024.01); B01D 46/24 (2006.01); B01D 46/82 (2022.01); B01J 23/58 (2006.01); F01N 3/022 (2006.01); F01N 3/035 (2006.01)
CPC B01J 35/56 (2024.01) [B01D 46/2418 (2013.01); B01D 46/82 (2022.01); B01J 23/58 (2013.01); F01N 3/0222 (2013.01); F01N 3/035 (2013.01); B01D 2279/30 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A particulate filter disposed in an exhaust passage of an internal combustion engine and configured to be used for collecting particulate matter in an exhaust gas emitted from the internal combustion engine,
the particulate filter comprising:
a base material having a wall-flow structure, the base material including an inlet cell, an outlet cell, and a porous partition wall, the inlet cell being open only in an end portion at an exhaust gas inflow side, the outlet cell being adjacent to the inlet cell, the outlet cell being open only in an end portion at an exhaust gas outflow side, the porous partition wall partitioning the inlet cell and the outlet cell; and
a wash-coating layer formed inside the partition wall, wherein
the wash-coating layer includes
an inlet layer having a predetermined thickness from a surface of the partition wall in contact with the inlet cell toward inside of the partition wall, the inlet layer having a predetermined length from a vicinity of the end portion at the exhaust gas inflow side along an extension direction of the partition wall, and
an outlet layer having a predetermined thickness from a surface of the partition wall in contact with the outlet cell toward inside of the partition wall, the outlet layer having a predetermined length from a vicinity of the end portion at the exhaust gas outflow side along the extension direction of the partition wall,
the thickness and the length of each of the inlet layer and the outlet layer are set such that the inlet layer and the outlet layer partially overlap with each other,
the inlet layer contains substantially no noble metal catalyst that promotes combustion of the particulate matter, whereas the outlet layer contains the noble metal catalyst,
the inlet layer is made of a main component or a mixture of the main component and an accessory ingredient,
the content of the main component in the inlet layer is 85% by mass or more,
the main component consists of at least one selected from the group consisting of alumina, silica, zirconia, magnesia, and calcia, and
the accessory ingredient consists of at least one selected from the group consisting of rare earth metal oxide and alkaline earth metal oxides.