Exhaust gas purifying filter and production of the same
US4632683A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 21, 1985 |
| Grant date | Dec 30, 1986 |
| Priority date | — |
| Expiry date | Nov 21, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24149
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An exhaust gas purifying filter having a multiplicity of inward being open at the one axial end and blocked at the other axial end, a multiplicity of outward passages parallel to the axis of the filter, the outward passages being open at one axial end and blocked at the other axial end, and having porous partition walls placed between the inward passages and the outward passages and separating the inward passages and the outward passages from one another, which is characterized in that the surface of the partition wall exposed to at least the inward passage has superficial pores communicating with internal pores in the partition wall, the superficial pores being composed of small pores having a diameter of 5 to 40 .mu.m and large pores having a diameter of 40 to 100 .mu.m, the number of the small pores being 5 to 40 times that of said large pores and production of the same.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.