Anionic water soluble polymer made by reverse phase emulsion polymerization
US6310157A · kind A · utility
8Cited by
13References
10Claims
0Family size
Assignee
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Key dates
| Filing date | May 19, 1999 |
| Grant date | Oct 30, 2001 |
| Priority date | — |
| Expiry date | May 19, 2019 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21H17/44
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Paper is made by a dual soluble polymer process in which a cellulosic suspension which usually contains alum or cationic coagulant is first flocculated with a high IV cationic synthetic polymer or cationic starch and, after shearing, the suspension is reflocculated by the addition of a branched anionic water soluble polymer having IV above 3 dl/g and tan delta at 0.005 Hz of at least 0.5. The process gives an improved combination of formation, retention and drainage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.