Method of controlling silica deposition in aqueous systems
CA 2035064 C · Owner: Nguyen, Truc K. · Inventors: Sherwood, Steven P.; Mcdaniel, Cato R.; Nguyen, Truc K.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for the inhibition of silica deposition on the internal surfaces of an aqueous system comprising adding to the aqueous system a phosphonate compound and a water soluble polymer having the structure:, wherein M is a water soluble cation. The aqueous systems in which the water soluble phosphonate and polymer are particularly effective on cooling water and boiler systems.
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 28, 1991 and granted October 31, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 28, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 28, 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.