Preparation of bleached chemithermomechanical pulp
US5298118A · kind A · utility
6Cited by
5References
12Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 29, 1992 |
| Grant date | Mar 29, 1994 |
| Priority date | — |
| Expiry date | Jul 29, 2012 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21C3/06
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Bleached chemithermomechanical wood pulp having a high degree of whiteness is economically prepared by mechanically disintegrating and chemically digesting lignocellulosic material with sulfite at a temperature of at least 100.degree.C. under saturated water vapor pressure and thereafter bleaching the pulp thus treated with hydrogen peroxide in an alkaline medium, and wherein no solids or liquids are removed from the pulp from the outset of treatment through completion of the bleaching step.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.