Process for making bis(hydroxyphenyl)methanes
CA 1181431 A · Owner: Ort, Morris R. · Inventors: Ort, Morris R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Bis(hydroxyphenyl)methanes are prepared by reaction of phenol and formaldehyde in a two-phase mixture containing aqueous phosphoric acid. The reaction conditions can be selected to provide high yields of bis(hydroxyphenyl)methanes or to yield bis(hydroxyphenyl)methanes containing a high concentration of the 4,4'-isomer.
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 January 22, 1985. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 22, 2002.
- 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.