Insoluble vinyl lactam clarifiers
US4764588A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 9, 1987 |
| Grant date | Aug 16, 1988 |
| Priority date | — |
| Expiry date | Mar 9, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F6/008
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
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.degree. C. and about 250.degree. 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 solubles (NVWS) content less than 2% and a filter flow rate greater than 95.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.