Amine salts of sulfomethylated lignin
US4732572A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 3, 1985 |
| Grant date | Mar 22, 1988 |
| Priority date | — |
| Expiry date | Oct 3, 2005 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD06P1/46
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Disclosed is a method for the production of a sulfomethylated lignin amine salt from the lignin by-product of the black liquor residue of a kraft pulping process and the use of lignin amine salts as additives in other chemical compositions. The lignin amine salt is produced by precipitating lignin from the black liquor and reacting the precipitated lignin slurry with formaldehyde. Thereafter, the lignin slurry is acidified to a pH of about 2 to 3 and water-washed to remove inorganic salts and other impurities therefrom. The washed methylolated lignin is reacted with an organic amine and a sulfur-oxygen-containing compound, such as sulfur dioxide to form the sulfomethylated lignin amine salt. The sulfomethylated lignin amine salt products are disclosed as an additive in dyestuff and printing ink compositions, as well as a sequestrant in pesticide compositions, with improved results over certain lignin salts heretofore employed as additives in such compositions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.