Nitrite based rust inhibitor complex

Abstract From the Canadian patent

An oil dispersible rust inhibitor consisting of a chemical complex of a metal nitrite with a hetero-atomic aprotic polar organic solvent. Preferred metal nitrites are the alkali, alkaline earth metals or nickel zinc, or cadmium, nitrites. Preferred solvents are dimethylsulfoxide dimethyl-, formamide, dibutylformamide n-methylpyrrolidone, dioxane, ethylcarbonate tetrahydrofuran and their derivatives. The complex is prepared by reacting a nitrite ion with a solution of a basically reacting metal salt in the selected solvent. The excess metal salt is removed from the solution after completion of the reaction. The complex is readily solubilized in oil through the use of common dispersants.