Meta-halogenated dibenzylphenols
CA 2027196 A1 · Owner: Mendoza, Abel · Inventors: Mendoza, Abel
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Thermally stable methylene-bridged polyphenols such as 2,4-bis(4-hydroxy-3,5-dimethyl)-3,5-dibromo-6- -methylphenol are prepared by contacting (1) a substituted phenol having at least one halogen substituted on the aromatic ring in a position meta to the phenolic hydroxyl and at least one halomethyl group substituted on the aromatic ring in a position ortho or para to the phenolic hydroxyl with (2) an o,o-dialkylphenol having hydrogen on the aromatic ring position which is para to the phenolic hydroxyl under alkylation conditions. 35,982-F
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 October 9, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 9, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 9, 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.