Blended drilling fluid thinner
CA 2104559 C · Owner: Phillips Petroleum Company · Inventors: Patel, Bharat B.; Stewart, Wayne S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A blended additive composition, which is useful for thinning aqueous drilling fluids, is disclosed. The composition includes a first component selected from the group including: a modified tannin a, modified lignite and sodium lignosulfonate; a second component being a polymer prepared from acrylic acid; and a third component being a metal compound selected from the group of metals including iron tin, chromium, manganese, titanium, aluminum and zinc.
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 August 20, 1993 and granted December 9, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 20, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 20, 2015.
- 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.