Acid Proof Synthetic Inorganic Pigments

  Synthetic Red Oxide as per IS 44 : 1991, Grade 2. (1) Volatile Matter 0.50% by mass (max) (2) Residue on sieve (B.S 240 mesh) 0.50% by mass (max) (3) Oil absorption - +/- 10 of approved sample. (4) Color Staining Power Not inferior to approved sample. Under Tone (Close match to the approved sample). (5) Matter soluble in matter 0.50% by mass (max) (6) Sum of water soluble Chloride and Sulphate expressed as CL and SO4 0.10% by mass (max). (7) Acidity (as H2SO4) or alkalinity (as NaOH) 0.10% by mass (max) (8) pH of aqueous extract - +/- 1 of approved sample. (9) Total Iron (as Fe2O3) 94% by mass (min) (10) Ferrous Iron (Fe2O3) 1.5% by mass (max) (11) Calcium compounds (as Cao) 2.25% by mass (max)