Acid dyes are a type of water-soluble dyes with acidic groups in the structure, which are dyed in an acid medium. Most acid dyes contain sodium sulfonate, which is soluble in water, bright in color and complete chromatogram. It is mainly used for dyeing wool, silk and nylon, but also for leather, paper, ink, etc. Generally no tinting power to cellulose fibers.
Strong Acid Dyes
The earliest developed acid dye requires dyeing in a strong acid dye bath. It has a simple molecular structure, low molecular weight, contains sulfonic acid or carboxyl groups, and has little affinity for wool. It can move evenly on wool. It is evenly dyed, so it is also called acid level dyeing dye, but the shade is not deep, the washing fastness is poor, and the wool is damaged during dyeing, and the dyed wool feels poor. Such as Acid Red G (ie C.I. Acid Red 1).