Hydroxyalkane phosphonic acids and derivatives thereof and lubricants containing same
CA 2009487 C · Owner: The Lubrizol Corporation · Inventors: Rizvi, Syed Q. A.; Di Biase, Stephen A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to lubricating compositions containing hydroxyalkane phosphonic acids and derivatives thereof. More specifically, this invention relates to hydroxyalkane phosphonic acids which can be reacted to form salts with basic materials, including overbased detergents, dispersants and amines. These materials can be particularly useful in lubricating compositions. The hydroxyalkane phosphonic acid is represented by the following formula:, wherein X is oxygen sulfur or a secondary amino group, n, is an integer from 1 to 8 Y is hydrogen or a phosphonic, acid group and R is an alkyl group having from 1 to about 100 carbon atoms.
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 February 7, 1990 and granted June 14, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 7, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 7, 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.