MAGNETIC METAL OR ALLOY PIGMENTS, PROCESS FOR THEIR PRODUCTION, AND THEIR USE

摘要

A pigment of a magnetic metal or alloy thereof carrying, in about 0.2 to 30% of the weight of the metal or alloy, a coating of at least one member selected from the group consisting of an ortho-silicic acid ester, a hydrolyzate thereof and a condensation product thereof. Optionally it also carries a corrosion inhibitor. The coated pigment is produced by suspension of the untreated pigment in a liquid medium containing the ortho-silicic acid ester or derivative thereof, and optionally the corrosion inhibitor, followed by separation and drying at 50 DEG to 250 DEG C. The resulting pigment is non-pyrophoric and of high performance properties suitable for use in magnetic recording media.