Red iron oxide
Inexpensive, lightfast and inert: red iron oxide gives red-oxide primers, barn reds and earthy tints their color.
Red iron oxide is iron(III) oxide, Fe₂O₃, in its hematite crystal form, listed in the Colour Index as Pigment Red 101 (synthetic). It is produced synthetically for coatings to control particle size and purity.
It is used in red-oxide primers, floor and barn paints, tinting pastes, and to color concrete coatings, polyurea liners and epoxy floors in reds, browns and terra-cotta shades.
Iron oxides are chemically stable, insoluble, highly lightfast and resistant to alkali, which suits concrete and outdoor use. They also absorb UV, helping protect the binder. Red oxide does not provide galvanic or strong inhibitive corrosion protection by itself; its role in primers is mainly color and barrier.
Low toxicity, but dry powder creates dust; control dust and wear particulate protection when handling bags.
The red color comes from iron oxide, which mainly adds color and some barrier effect. Corrosion protection depends on the primer’s binder and any inhibitive pigments it contains.
Yes. It is alkali-resistant and lightfast, which suits concrete stains and coatings.
