| abstract |
A composition, in contact with a corrodable metal surface, comprising:n a) an aqueous-based or oil-based system; and b) as an inhibitor for protecting the metal surface against corrosion, at least one compound having the formula I or II:n in which nR is C₄-C₂₀alkyl, C₄-C₂₀alkyl interrupted by one or more oxygen atoms, C₄-C₂₀alkenyl, C₆-C₁₀aryl, C₇-C₁₅alkaryl, C₇-C₁₅aralkyl or C₅-C₁₂cycloalkyl; nR¹, R² and R³ are the same or different and each is methyl or, preferably, hydrogen; nM is hydrogen, a metal ion, ammonium or substituted ammonium ion; na is 0 or 1; nb is 0 or an integer from 1 to 6, preferably 0, 1, 2 or 3 especially 0 or 1; and nc is an integer from 1 to 6; and/or at least one compound having the formula II:n in which R, R³ and a are as defined above. |