Process for the purification of polyvinyl chloride
CA 1094734 A · Owner: Tenneco Chemicals, Inc. · Inventors: Feldman, Martin L.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Inventor: Martin L. Feldman, a citizen of the United States of America, residing at East Brunswick, County of Middlesex, State of New Jersey. Abstract of the Disclosure The discoloration of polyvinyl chloride that usually occurs when a slurry containing this polymer is heated at a temperature above 70°C. to reduce its monomer content to less than 10 ppm is minimized or prevented by carrying out the heating step in the presence of an oxidizing agent. - 1 -
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 27, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 27, 1998.
- 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.