Expired Canadian patentCanada
Clay and mica replacement with cmc in joint compound
CA 2039099 C · Owner: Aqualon Company · Inventors: Podlas, Thomas J.
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Sodium carboxymethylcellulose (CMC) with a D.S. between 0.35 and 0.75 and D.P. between 200 and 4000 serves as a swelling agent and can replace clay and/or mica in a joint compound formulation when used in an amount of 0.01 to 0.5% by weight.
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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 March 26, 1991 and granted December 18, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 26, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 26, 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.
FiledMarch 26, 1991
GrantedDecember 18, 2001
Term endedMarch 26, 2011
Patent numberCA 2039099 C
Classification (IPC)C09D5/34 +2 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.