8 / | HD | BLEACHING AND DYEING; FLUID TREATMENT AND CHEMICAL MODIFICATION OF TEXTILES AND FIBERS |
636 | DF | DYE OR POTENTIAL DYE COMPOSITION, ADDITIVE, TREATMENT, PROCESS, PRODUCT, OR ANCILLARY DYE OPERATION {12} |
654 | .~ Basic (cationic) dye containing strongly basic onium or alkylene imine group {1} | |
655 | DF | .~.~> Heterocyclic onium group, e.g., pyridinium, etc. |