Bleaching of cellulosic pulps using hydrogen peroxide
US4732650A · kind A · utility
21Cited by
3References
41Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 15, 1986 |
| Grant date | Mar 22, 1988 |
| Priority date | — |
| Expiry date | Sep 15, 2006 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21C9/1005
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Bleaching of wood pulp is improved by the combination of a pretreatment of the pulp with a polyaminocarboxylic acid, e.g. ethylenediaminetetraacetic acid, prior to bleaching with an alkaline aqueous peroxide solution containing a stabilizing amount of an aminophosphonic acid derivative together with a polymer of an unsaturated carboxylic acid or amide or an alkylsulfonic acid substituted amide.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.