• C.A.S. No.
• 115-40-2
• M.F.
• C₂₁H₁₆Br₂O₅S
• M.Wt.
• 540.24gm/mole

Specifications:

• Dye content
• >95%
• Transition range
• pH 5.2–6.8
  Yellow – Purple
• Solubility 0.1%(95%Ethanol)
• Clear solution
• Absorption maximum (pH 5.2) λ₁max
• 427–431nm
• Absorption maximum (pH 6.8) λ₂max
• 588–590nm
• Absorptivity (A1%/1cm at pH 5.2 at λ₁max)
• 400–500
• Absorptivity (A1%/1cm at pH 6.8 at λ₂max)
• 1000–1100
• Loss on drying (110^oC)
• <1%