(nm)Maximum absorpti-
on wavelength 6.5(Brown yellw)-8.0(Purple)
λ1(pH 1.2) 503-506
λ2(pH 3.0) 430-435
λ3(pH 6.5) 430-435
λ4(pH 8.0) 557-560
Mass absorptivity,L/(cm.g)
α1(λ1,(pH 1.2,) 110-123
α2(λ2,(pH 3.0,) 60-68
α3(λ3,(pH 6.5,) 62-72
α4(λ4,(pH 8.0,) 120-135
Solubility in alkali PASS
Drying loss,% ≤1.0
Ignition residue,% ≤0.2






