Ultra-high filtration filter
CA 1298751 C · Owner: Berger, Richard M. · Inventors: Berger, Richard M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An ultra-high efficiency cigarette filter is formed from a web of entangled ultra-fine melt blown plastic fibers of extremely low bulk density. The web is formed into a substantially cylindrical rod and is encapsulated in and supported by an external plastic tube which adheres to the outer surface of the rod over the entire area of contact therebetween. Cigarette filters in accordance with the invention may have filtration efficiencies in excess of 80%. The disclosure also includes processes and apparatus for manufacturing the high efficiency filters.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted April 14, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 14, 2009.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.