Method of micaceous iron oxide (mio) pigment production

摘要

This invention relates to a method for producing micaceous iron oxide (α-Fe₂O₃) particles in the form of substan­tially hexagonal or circular platelets from insoluble iron(II) compounds comprising ferrous hydroxide, ferrous carbonate or ferrous ferrite and mixtures thereof. The compounds are oxidized at an elevated temperature in the range of 150 °C to 300 °C, in an aqueous solution of a concentrated alkali metal hydroxide of a concentration between 2 and 16 moles per liter, using gaseous oxygen as the sole oxidizing agent.;The product represents a valuable pigment, widely applied as a basic component in barrier anticorrosion coating materials.