Methods for the production of sulfurized diphenyloxides and compositions made therefrom
CA 2358384 A1 · Owner: Wu, Margaret May-Son · Inventors: Trotto, Philip; Wu, Margaret May-Son; La Pierre, Rene B.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to methods for production of sulfurized diphenyloxides wherein a diphenyloxide is reacted with elemental sulfur in the presence of solid acid catalyst. The solid acid catalyst can be a zeolite or a catalytic amount of a Friedel-Crafts compound. The present invention further relates to a composition containing between 40 and 80 weight percent diphenyloxide; no more than 15 weight percent diphenyloxide thiol; between 5 and 45 weight percent phenoxathiin; and between 3 and 50 weight percent total of bis(diphenyloxide) sulfide, diphenyloxide phenoxathiin sulfide and , bis(phenoxathiin) sulfide.
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 December 30, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 30, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 30, 2021.
- 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.