Treatment of cellulosic material and compositions for use in this
US5637191A · kind A · utility
5Cited by
6References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 17, 1994 |
| Grant date | Jun 10, 1997 |
| Priority date | — |
| Expiry date | Oct 17, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/64
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A process of de-inking waste paper can be operated under conditions using a simple combination of chemicals to result in a waste liquor that is substantially environmentally friendly. The process comprises forming a pulp from the waste paper in a aqueous medium that has a pH of between 6 and 9 and that is substantially free of dissolved phosphate and that includes an ink-dispersing amount of polycarboxylic acid dispersing agent, and separating the ink from the pulp. The use of a cationic surfactant for promoting flotation is particularly desirable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.