Selective crosslinking of low molecular weight sulfonated lignins and lignosulfate products produced thereby
US4546173A · kind A · utility
8Cited by
16References
14Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 30, 1984 |
| Grant date | Oct 8, 1985 |
| Priority date | — |
| Expiry date | Oct 30, 2004 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD06P1/62
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process for preparing sulfonated lignins suitable for use as dispersants and additives in dye compositions wherein sulfonated lignins are post-sulfonation crosslinked with a crosslinking agent of the aldehyde, epoxide, or polyhalide type at a pH range of between about 6.1 to 9 to selectively crosslink the low molecular weight fraction of the sulfonated lignins to provide improved heat stability and dispersibility of the sulfonated lignins in dye compositions. The invention also concerns disperse and vat dye compositions, and printing gels, containing the sulfonated lignins as a dispersing agent or additive.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.