Method for the production of unbleached sulphite cellulose or bleached cellulose from a defibrated knot pulp
US4230524A · kind A · utility
3Cited by
3References
5Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jun 28, 1979 |
| Grant date | Oct 28, 1980 |
| Priority date | — |
| Expiry date | Jun 28, 1999 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21C5/00
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Knots separated from sulphite cellulose produced by a sulphite cellulose cooking process are converted to unbleached sulphite cellulose by first separating and defibrating the sulphite knots and then treating the defibrated sulphite knots with oxygen under pressure in an alkaline milieu at an elevated temperature. The resultant cellulose may be bleached by itself, or mixed with sulphite cellulose produced from knot-free cellulose pulp for bleaching therewith.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.