Properties of acid dyes



        i.            Acid dyes are water soluble.
      ii.            Good light fastness
    iii.            Direct affinity toward protein fibres and polyamide fibres.
    iv.            Bright shade possible
      v.            Sodium salt of organic acid.
    vi.            They are always applied in organic or inorganic acid medium.
  vii.            Most of cellulose fibres will not exhaust acid dyes.