Structural formula

Alizarin red S

C.A.S No. 

C.I. number

58005

Class

Anthraquinone

Solubility in 0.1%  water

Absorptivity 1% 1 cm

(pH 6.3) at lamda max 421.5 nm

 150

(pH 9.3) at lamda max 525.5 nm

Loss on drying

3.58 %