Process for the production of high molecular weight, optionally branched polyarlene sulfides
CA 2003420 A1 · Owner: Bayer Aktiengesellschaft · Inventors: Schmidt, Manfred; Dorf, Ernst-Ulrich; Alewelt, Wolfgang
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A b s t r a c t, The invention relates to a process for the production of high molecular weight, optionally branched polyarylene sulfides having a low content of organically bound halogen. The are prepared by reaction of alkali sulfides and/or alkali hydrogen sulfides with aromatic dihalogen compounds in a polar organic solvent. Le A 26 274
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 November 21, 1989. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 21, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 21, 2011.
- 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.