Process for the preparation of polydric phenols
CA 1090827 A · Owner: Bayer Aktiengesellschaft · Inventors: Schwerdtel, Wulf; Seifert, Hermann; Waldmann, Helmut
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract Of The Disclosure, A process has been invented for the preparation of pyrocatechol and hydroquinone which comprises reacting a solution which is substantially anhydrous and free from hydrogen peroxide, of a percarboxylic acid in an inert organic solvent with phenol at temperatures from -10°C to 80°C. The compounds obtained according to the invention are known, important industrial chemicals which are used in large amounts in the field of photography and of dyestuffs and plastics and in the field of scents and flavourings. * * * * *
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
- Granted December 2, 1980. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 2, 1997.
- 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.