Cigarette filters
US8201564B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 4, 2006 |
| Grant date | Jun 19, 2012 |
| Priority date | — |
| Expiry date | Aug 10, 2030 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD06M2101/08
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Fibrous material suitable for incorporation into filter elements of smoking articles such as cigarettes are impregnated with additives and agents such as flavorants, flavorant-enhancers and/or free radical scavengers. The fibrous material is contacted with the additive dispersed in a high pressure gas or supercritical fluid (SCF) held at elevated pressures. The high pressure gas or SCF swells the fibrous matrix and enables the additive to be incorporated within the matrix. When pressure is reduced, the gas or SCF vaporizes and leaves the additive embedded in the fiber interstices. As a result, the additive is slowly released over a finite period of time. When incorporated into a cigarette filter, the additive is released at a desired rate from the interior of the fibrous filter into the cigarette smoke.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.