The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 26, 1998
Filed:
Sep. 12, 1996
Peter Dilling, Mt. Pleasant, SC (US);
Sallie B Huguenin, Folly Beach, SC (US);
Westvaco Corporation, New York, NY (US);
Abstract
Improved dyestuff compositions comprising a dye cake and a dye dispersant are disclosed wherein the dye dispersant comprises sulfonated or sulfomethylated lignin of increased activity and improved heat stability properties and which dispersants are disclosed to be prepared by substantial removal of the low molecular weight component of the sulfonated and sulfomethylated lignin. Exclusion of the low molecular weight portion of the dispersant may be accomplished by fractionation of the sulfonated or sulfomethylated lignin to remove a substantial portion of the molecules having a molecular weight below 3,000. Alternatively, in the case of lignin recovered from sulfate or soda wood pulping processes, the lignin may be fractionated to remove a substantial portion of the molecules having a molecular weight below 3,000 prior to sulfonation or sulfomethylation.