Insoluble vinyl lactam clarifiers
CA 1296476 C · Owner: Smith, Terry E. · Inventors: Smith, Terry E.; Cottrell, Ian W.; Pelesko, John D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to highly filterable polyvinyl polypyrrolidone particles and to the process for improving filterability of standard polyvinyl polypyrrolidone granules, wet cakes and slurries which comprises heating granular polyvinyl polypyrrolidone containing a minor amount of non-crosslinked and/or unsaturated sites while maintaining between 1 wt. % and 20 wt. % moisture at a temperature of between about 50°C. and about 250°C. under a pressure of from about 5 psig. to about 200 psig. and collecting product having an average particle size distribution between about 40 and 400 mesh a non-volatile water solubtes (NVWS) content less than 2 and a filter flow rate greater than 95.
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 February 25, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 25, 2009.
- 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.