Expired Canadian patentCanada
Prevention of subsurface seepage by acrylic acid polymers
CA 1059849 A · Owner: Nalco Chemical Company · Inventors: Robinson, Donald G.; Busler, William R.
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Porous substrata of small bodies of non-flowing waters are contacted with acrylic acid polymers having at least 20%, by weight acrylate to retard excess water loss due to seepage.
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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
- Granted August 7, 1979. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 7, 1996.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Filed—
GrantedAugust 7, 1979
Term endedAugust 7, 1996
Patent numberCA 1059849 A
Classification (IPC)E02B5/02 +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.