Tobacco smoke filter
US4195649A · kind A · utility
23Cited by
5References
20Claims
0Family size
Assignees
Inventors
Key dates
| Filing date | Jan 13, 1978 |
| Grant date | Apr 1, 1980 |
| Priority date | — |
| Expiry date | Jan 13, 1998 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA24D3/163
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A tobacco smoke filter capable of selectively removing irritating materials and unpleasant bitter components from tobacco smoke and containing as a filter element nitrogen-containing activated carbon fibers produced by oxidizing acrylonitrile polymer fibers and then activating the oxidized fibers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.