Method for producing stain resistant polyamide fibers
AssigneeE. I. Du Pont de Nemours and Company
InventorsImrich Greschler, Creighton P. Malone, Armand P. Zinnato
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Abstract
Polyamide fibers are made stain resistant by treating them with a sulfonated naphthol- or sulfonated phenol-formaldehyde condensation product. Applying the stain-resist compounds at pH values of between 1.5 and 2.5 renders them stable to yellowing upon exposure to agents in the environment such as NO.sub.2.
Claims2
In a process for applying sulfonated phenol-formaldehyde or sulfonated naphthol-formaldehyde condensation products to polyamide textile articles to render them stain resistant, the improvement comprising applying the condensation products at a pH of between 1.5 and 2.5 whereby yellowing of the treated articles due to exposure to NO.sub.2 in the atmosphere is reduced.
Dependencies are inferred from the claim text.