Method for control of washcoat distribution along channels of a particulate filter substrate
US7094728B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 11, 2003 |
| Grant date | Aug 22, 2006 |
| Priority date | — |
| Expiry date | Oct 14, 2024 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S502/514
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Disclosed herein is a method of distributing a washcoat along channels of a particulate filter substrate, the method including: forcing a washcoat slurry a predetermined distance into the channels, the predetermined distance being less than or equal to the full length of the channels; clearing an excess amount of washcoat slurry from the channels; and arranging a remainder of the washcoat slurry within the channels, the arranging including applying a first vacuum to a first end of the particulate filter substrate after the clearing. In one embodiment the clearing includes applying a second vacuum to a second end of the particulate filter substrate. In another embodiment, the clearing includes pulling the excess washcoat slurry from the channels. The predetermined distance may be less than or equal to the full length of the channels. The arranging may provide a layer of a washcoat composition comprising a catalytically active material arranged anisotropically along a length of the channels of the particulate filter substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.