Westvaco Corporation

Gerald Prazak

Peter Dilling

Catherine C Cashman

Vaughn R Loeffler

Karin U Thomas

A carbon black composition comprising carbon black and a lignin dispersant prepared by the steps of methylolating a lignin compound by reaction of less than about 2 moles formaldehyde per 1,000 grams of the lignin, and sulfonating the methylolated lignin by reaction from about 2.5 to 3.5 moles of the sulfite or bisulfite compound per 1,000 grams of lignin at an initial reaction pH of below about 6.6 and at a temperature of at least about 170.degree. C., while allowing the pH of the reaction mixture to rise to a final pH of greater than 7.5 to sequentially sulfomethylate the aromatic nucleus and sulfonate the side chain of the lignin.

Lignosulfonate additive-containing carbon black compositions

A method of producing a lignin dispersant composition comprising the steps of methylolating a lignin compound by reaction of less than about 2 moles formuladehyde per 1,000 grams of the lignin, and sulfonating the methylolated lignin by reaction from about 2.5 to 3.5 moles of the sulfite or bisulfite compound per 1,000 grams of lignin at an initial reaction pH of below about 6.6 and at a temperature of at least about 170.degree. C., while allowing the pH of the reaction mixture to rise to a final pH of greater than 7.5 to sequentially sulfomethylate the aromatic nucleus and sulfonate the side chain of the lignin. The products of the method find particular use as dispersants in dye compositions and carbon black compositions with lower viscosity and extended shelf-life storage of the composition.

Production of lignosulfonate additives

Improved sulfonated lignin surfactants are provided for use as dispersants in dyestuffs. The process for providing the improved surfactants relates to using metals and borate salts to react with the azo dye reducing dihydroxy functions of the lignin molecule through chelation and ester formation mechanisms thereby inhibiting the lignin's azo dye reducing characteristics.

Azo dye reduction improvement of lignin

Dyestuff composition for use in dyeing cotton fibers comprising a mixture of dye cakes of various colors, primarily direct or vat dyes, and sulfonated lignin dye dispersants having retarding properties. The dye dispersants of this invention are the reaction product of a sulfonated lignin and from 0.1 to 9.0% by weight of the total dispersant of a water-soluble magnesium salt, preferably 1.0 to 2.0% by weight. These dye dispersants are excellent dye retarders by eliminating uneven dyeing, and reduce foaming problems associated with dispersed vat dyes. These dye dispersants having retarding properties are used when a plurality of dye cakes are used in one dyeing operation to produce the much desired levelling effect on the process of vat dyeing.

Dyestuff compositions containing modified sulfonated lignin dye

Disclosed herein is an improved process for producing sulfonated lignin surfactants for use as dispersants for disperse dyes and vat dyes. The improved process is to react a sulfonated lignin and epihalohydrin under certain conditions to block a portion of the free-phenolic hydroxyl group and at the same time cross-link the lignin molecules to increase the molecular weight. Another aspect of the process of this invention is to oxidize the thus treated lignin to stabilize its properties. Dispersants made according to this process have improved fiber staining and heat stability properties over other lignin-based dispersants.

Growing community of inventors

Charleston, SC, United States of America

Gerald Prazak