Active anti-corrosion pigments based on calcium oxide, aluminium oxide and iron oxide

Abstract

An anti-corrosion pigment comprising about 30.0 to 2.0 mole % of CaO and about 70.0 to 98.0 mole % of Me.sub.2 O.sub.3, wherein Me.sub.2 O.sub.3 is (1-x) Al.sub.2 O.sub.3 and x Fe.sub.2 O.sub.3, x is from 0 to 1 and up to about 25 mole % of the Fe.sub.2 O.sub.3 may be replaced by the corresponding quantity of Mn.sub.2 O.sub.3, and having a specific surface area according to BET of about 0.1 to 200 m.sup.2 /g and a percentage weight loss per gram of pigment, as determined by the Thompson corrosion test, of less than about 0.05% per gram of pigment is produced by calcining the corresponding metal oxides or materials which form the metal oxides on calcination at about 200.degree. to 1100.degree. C. The pigments are especially useful in making up anti-corrosion paints and lacquers.

Dependencies are inferred from the claim text.