IRON OXIDE PIGMENT AND METHOD FOR PRODUCTION THEREOF Russian patent published in 2015 - IPC C09C1/24 C01G49/06 

FIELD: chemistry.

SUBSTANCE: iron oxide pigment contains α-modified iron (III) oxide with a plate-like crystal shape. Content of Fe₂O₃ in the pigment is 97-99 wt %. The crystals have average diameter of 0.1-0.8 mcm, with the ratio of the diameter to the thickness of the crystals of 0.1-0.2. The method of producing iron oxide pigment includes oxidative hydrolysis of aqueous iron (II) sulphate solutions at 10-40°C, followed by hydrothermal treatment of the formed products in an alkaline medium at 150-250°C. Hydrolysis of the suspensions obtained from the aqueous iron (II) sulphate solutions is carried out at pH=10-13, and oxidation is carried out with hydrogen peroxide.

EFFECT: invention reduces the average size of iron oxide crystals for use in paint compositions with low viscosity of the binder, particularly in water-dispersed compositions.

2 cl, 1 tbl, 7 ex