METHOD FOR DYING ARAMIDE FIBER Russian patent published in 2021 - IPC D06P3/00 

FIELD: fiber dying.

SUBSTANCE: invention relates to the field of technology for producing dyed heat- and fire-resistant aramid yarns and can be used in the chemical industry directly in the production of aramid yarns. A method for dyeing aramid fiber by introducing an acidic metal-containing dye at the stage of polymer synthesis or after polymer synthesis with subsequent spinning of a fiber from a solution based on aprotic amide solvents by a wet or dry-wet method is described. Aramid fiber is dyed with acid metal-containing dyes, with a general formula of Ме(-О-)₂Кр(-SO₃Na)_n, in an amount of 0.5-5.0% by weight of the polymer.

EFFECT: proposed method makes it possible to obtain uniform and intense colors of a wide range, resistant to washing and friction while maintaining high physical and mechanical properties.

4 cl, 2 tbl