| 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} |
| 638 | DF | .~ Mixed dyes, noncomplexed {4} |
| 639 | DF | .~.~ Azo {2} |
| 641 | | .~.~.~ Sulfonated azo |