Lignin by-products of paper-making process
US4740591A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 13, 1987 |
| Grant date | Apr 26, 1988 |
| Priority date | — |
| Expiry date | Apr 13, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09D11/03
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method of producing a lignin by-product of the black liquor residue of a kraft pulping process having improved water-solubility in amine salt form wherein the lignin precipitate of the black liquor residue is water-wash purified and maintained at moderately acid pH of no lower than about 5. The lignin may then be combined in aqueous slurry with an organic amine, such as monoethanolamine, to provide a highly stable aqueous solution of the amine salt of the lignin. The water-soluble lignin salt is particularly suited for use as an additive in water-based pigment printing compositions. The lignin amine salt functions as a grinding agent for the pigment in formulating and as a binder for the pigment in the printing process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.