Chlorotrifluoroethylene/perfluoro (alkyl vinyl ether) copolymer
CA 2039666 C · Owner: Ihara, Kiyohiko · Inventors: Ihara, Kiyohiko; Yamaguchi, Fumihiko
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention provides a copolymer comprising chlorotrifluoroethylene and 0.01 to 1% by mole of perfluoro(alkyl vinyl ether) of the formula: Rf-O-CF=CF2 (I), wherein R f is a C3-C6 perfluoroalkyl group. The copolymer has a melt flow rate of 0.01 to 200 x 10-3 cc/sec. good mechanical strength and a sufficiently high melting point. The copolymer of the present invention is suitable for molding into tubes and films for a variety of uses.
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
- Filed April 3, 1991 and granted October 23, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 3, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 3, 2013.
- 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.