Clay mixture having contamination resistance
CA 2008222 C · Owner: Clem Environmental Corporation · Inventors: Clem, Arthur James
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A mixture of swellable clay, such as bentonite is charged, with an additive which provides an excess of single-charged cations which tend to neutralize the deleterious effects of double-charged cations which are naturally present in seawater and industrial waste. The mixture is deposited on and carried by a sheet to facilitate its uses as a pond liner or a foundation sealant.
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 January 22, 1990 and granted February 15, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 22, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 22, 2012.
- 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.