Porous ceramic honeycomb filter
US5545243A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 12, 1994 |
| Grant date | Aug 13, 1996 |
| Priority date | — |
| Expiry date | Dec 12, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24744
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A porous ceramic filter has properties such that a porosity of the filter is more than 45% and less than 60%, a volume of pores having a pore size of less than 40 .mu.m is more than 60% of total volume of pores of the ceramic filter and an inequality of 1000M+85N.gtoreq.530 is satisfied, wherein M (m.sup.2 /g) is a specific surface of total pores continued from a surface to an inner portion of the filter and N (.mu.m) is a surface roughness of a surface of the filter. Preferably, the porous ceramic filter has a thermal expansion coefficient of less than 0.5.times.10.sup.-6 /.degree.C. within a temperature range of 40.degree..about.800.degree. C. in a direction parallel to a flow passage of the filter. The porous ceramic filter according to the invention is preferably used for eliminating soots in an exhaust gas from a diesel engine, and has a long operating time and requires less frequent filter regenerations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.