developed in 1920s for cellulose acetate

• neutral dyes (no electrical charge) for polyester, acetate, nylon
• no affinity for cellulose (some staining)
• slight coloration of acrylic and aramid (nomex, kevlar)
• hydrophobic and insoluble

structure of disperse dyes

• nonionic with very slight water solubility
• chromophores: azo, anthraquinone, nitrodiphenylamine, methine, quinophthalone
  • 50% monoazo
    • azo dyes are typically reds, oranges, yellows and browns
  • 25% AQ
    • aq dyes more typically blues, red, turquoise, or violet
    • more expensive than azo types but easier to level
  • 10% disazo (orange, black)

made up of a variety of chromophores (all insoluble)

disperse dye affinity

• displays affinity toward PET (including cationic dyeable PET), cellulose acetate, and nylon

why see staining of acrylic?

• remember acrylic = at least 85% acrylonitrile with anionic group

interaction of disperse dyes with fibers

• individual molecules of dye dissolve from small dispersed particles of dye and exhaust to fiber surface
• dye molecule diffuse into fiber and remain there due to hydrophobic interactions (soluble in fiber)