摘要 |
<p>This invention relates to antifreeze compositions comprising a mixture of organic acid corrosion inhibitors. The compositions comprise (a) from about 90% to about 99.89% by weight of a liquid alcohol which functions as a freezing point depressant, or mixture thereof; (b) from about 0.1% to about 5.5% by weight of a carboxylic acid selected from the group consisting of saturated and unsaturated aliphatic, and aromatic, mono-, di- and tri-carboxylic acids, and salts and isomers thereof, and any mixture thereof, and (c) from about 0.1% to about 2% by weight of a cyclohexenoic acid, or salt, isomer or mixture thereof, having the formula:wherein each of R1, R2 and R3 is, independently, selected from the group consisting of H, OH, COOH, C1-C10 alkyl groups, glycol esters, or combinations thereof. The antifreeze compositions provide surprisingly improved corrosion protection to aluminum surfaces, and in particular protection from cavitation-erosion corrosion, as compared to compositions containing only the carboxylic acid component or the cyclohexenoic acid component alone.</p> |