Patent · US Expired

Process for preparing lignosulfonates

US4521336A · kind A · utility

21Cited by
16References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 16, 1984
Grant dateJun 4, 1985
Priority date
Expiry dateApr 16, 2004

Classification

  • Technology area (CPC D)Textiles; Paper
  • CPC primaryD06P1/46
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

Disclosed herein is a process for preparing sulfonated lignins by selectively isolating lignins having molecular weights greater than 5,000 and subsequently reacting the lignin with sodium sulfite and an aldehyde. The resulting sulfonated lignins are useful as dispersants for disperse dyes and vat dyes.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.