Iron tallate is one of four substances (along with iron linoleate,
iron naphthenate and iron caprylate) that are included among commercial products known as metallic driers. They hasten the drying
of oleoresinous coating materials which are used to line the inner
surfaces of food-containing cans. Each preparation represents a
mixture rather than a single compound; its composition will
depend upon the nature and amount of organic acids in the parent
oil. Commercial preparations contain both ferrous and ferric salts,
with a total iron content of about 6 or 7 percent.
Iron tallate is prepared from commercial tall oil, which is a byproduct derived from the waste liquors of pine wood pulp mills.
The tall oil consists of a mixture of fatty and cyclic acids. Oleic
and linoleic acids comprise the bulk of the fatty acids although
some linolenic and stearic acids are also present. Metallic driers,
including iron tallate, are prepared from this mixture.
