Expired Canadian patentCanada
Smoking articles
CA 1307988 C · Owner: Dittrich, David John · Inventors: Dittrich, David John; Case, Paul David
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Low sidestream cigarettes comprise at least 20% expanded tobacco and cigarette paper of an air permeability of not more than 20 Coresta units, the tobacco density being between 100 and 260 mg cm-3.
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 September 29, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended September 29, 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.
FiledSeptember 2, 1988
GrantedSeptember 29, 1992
Term endedSeptember 29, 2009
Patent numberCA 1307988 C
Classification (IPC)A24D1/00 +1 more
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.